1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.85';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => '_where_field_BETWEEN'},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => '_where_field_IN'},
42 {regex => qr/^ ident $/ix, handler => '_where_op_IDENT'},
43 {regex => qr/^ value $/ix, handler => '_where_op_VALUE'},
44 {regex => qr/^ is (?: \s+ not )? $/ix, handler => '_where_field_IS'},
47 # unaryish operators - key maps to handler
48 my @BUILTIN_UNARY_OPS = (
49 # the digits are backcompat stuff
50 { regex => qr/^ and (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
51 { regex => qr/^ or (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
52 { regex => qr/^ nest (?: [_\s]? \d+ )? $/xi, handler => '_where_op_NEST' },
53 { regex => qr/^ (?: not \s )? bool $/xi, handler => '_where_op_BOOL' },
54 { regex => qr/^ ident $/xi, handler => '_where_op_IDENT' },
55 { regex => qr/^ value $/xi, handler => '_where_op_VALUE' },
58 #======================================================================
59 # DEBUGGING AND ERROR REPORTING
60 #======================================================================
63 return unless $_[0]->{debug}; shift; # a little faster
64 my $func = (caller(1))[3];
65 warn "[$func] ", @_, "\n";
69 my($func) = (caller(1))[3];
70 Carp::carp "[$func] Warning: ", @_;
74 my($func) = (caller(1))[3];
75 Carp::croak "[$func] Fatal: ", @_;
78 sub is_literal_value ($) {
79 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
80 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
84 # FIXME XSify - this can be done so much more efficiently
85 sub is_plain_value ($) {
87 ! length ref $_[0] ? \($_[0])
89 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
91 exists $_[0]->{-value}
92 ) ? \($_[0]->{-value})
94 # reuse @_ for even moar speedz
95 defined ( $_[1] = Scalar::Util::blessed $_[0] )
97 # deliberately not using Devel::OverloadInfo - the checks we are
98 # intersted in are much more limited than the fullblown thing, and
99 # this is a very hot piece of code
101 # simply using ->can('(""') can leave behind stub methods that
102 # break actually using the overload later (see L<perldiag/Stub
103 # found while resolving method "%s" overloading "%s" in package
104 # "%s"> and the source of overload::mycan())
106 # either has stringification which DBI SHOULD prefer out of the box
107 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
109 # has nummification or boolification, AND fallback is *not* disabled
111 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
114 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
116 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
120 # no fallback specified at all
121 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
123 # fallback explicitly undef
124 ! defined ${"$_[3]::()"}
137 #======================================================================
139 #======================================================================
143 my $class = ref($self) || $self;
144 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
146 # choose our case by keeping an option around
147 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
149 # default logic for interpreting arrayrefs
150 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
152 # how to return bind vars
153 $opt{bindtype} ||= 'normal';
155 # default comparison is "=", but can be overridden
158 # try to recognize which are the 'equality' and 'inequality' ops
159 # (temporary quickfix (in 2007), should go through a more seasoned API)
160 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
161 $opt{inequality_op} = qr/^( != | <> )$/ix;
163 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
164 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
167 $opt{sqltrue} ||= '1=1';
168 $opt{sqlfalse} ||= '0=1';
171 $opt{special_ops} ||= [];
172 # regexes are applied in order, thus push after user-defines
173 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
176 $opt{unary_ops} ||= [];
177 push @{$opt{unary_ops}}, @BUILTIN_UNARY_OPS;
179 # rudimentary sanity-check for user supplied bits treated as functions/operators
180 # If a purported function matches this regular expression, an exception is thrown.
181 # Literal SQL is *NOT* subject to this check, only functions (and column names
182 # when quoting is not in effect)
185 # need to guard against ()'s in column names too, but this will break tons of
186 # hacks... ideas anyone?
187 $opt{injection_guard} ||= qr/
193 return bless \%opt, $class;
197 sub _assert_pass_injection_guard {
198 if ($_[1] =~ $_[0]->{injection_guard}) {
199 my $class = ref $_[0];
200 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
201 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
202 . "{injection_guard} attribute to ${class}->new()"
207 #======================================================================
209 #======================================================================
213 my $table = $self->_table(shift);
214 my $data = shift || return;
217 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
218 my ($sql, @bind) = $self->$method($data);
219 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
221 if ($options->{returning}) {
222 my ($s, @b) = $self->_insert_returning($options);
227 return wantarray ? ($sql, @bind) : $sql;
230 # So that subclasses can override INSERT ... RETURNING separately from
231 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
232 sub _insert_returning { shift->_returning(@_) }
235 my ($self, $options) = @_;
237 my $f = $options->{returning};
239 my $fieldlist = $self->_SWITCH_refkind($f, {
240 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
241 SCALAR => sub {$self->_quote($f)},
242 SCALARREF => sub {$$f},
244 return $self->_sqlcase(' returning ') . $fieldlist;
247 sub _insert_HASHREF { # explicit list of fields and then values
248 my ($self, $data) = @_;
250 my @fields = sort keys %$data;
252 my ($sql, @bind) = $self->_insert_values($data);
255 $_ = $self->_quote($_) foreach @fields;
256 $sql = "( ".join(", ", @fields).") ".$sql;
258 return ($sql, @bind);
261 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
262 my ($self, $data) = @_;
264 # no names (arrayref) so can't generate bindtype
265 $self->{bindtype} ne 'columns'
266 or belch "can't do 'columns' bindtype when called with arrayref";
268 my (@values, @all_bind);
269 foreach my $value (@$data) {
270 my ($values, @bind) = $self->_insert_value(undef, $value);
271 push @values, $values;
272 push @all_bind, @bind;
274 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
275 return ($sql, @all_bind);
278 sub _insert_ARRAYREFREF { # literal SQL with bind
279 my ($self, $data) = @_;
281 my ($sql, @bind) = @${$data};
282 $self->_assert_bindval_matches_bindtype(@bind);
284 return ($sql, @bind);
288 sub _insert_SCALARREF { # literal SQL without bind
289 my ($self, $data) = @_;
295 my ($self, $data) = @_;
297 my (@values, @all_bind);
298 foreach my $column (sort keys %$data) {
299 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
300 push @values, $values;
301 push @all_bind, @bind;
303 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
304 return ($sql, @all_bind);
308 my ($self, $column, $v) = @_;
310 my (@values, @all_bind);
311 $self->_SWITCH_refkind($v, {
314 if ($self->{array_datatypes}) { # if array datatype are activated
316 push @all_bind, $self->_bindtype($column, $v);
318 else { # else literal SQL with bind
319 my ($sql, @bind) = @$v;
320 $self->_assert_bindval_matches_bindtype(@bind);
322 push @all_bind, @bind;
326 ARRAYREFREF => sub { # literal SQL with bind
327 my ($sql, @bind) = @${$v};
328 $self->_assert_bindval_matches_bindtype(@bind);
330 push @all_bind, @bind;
333 # THINK: anything useful to do with a HASHREF ?
334 HASHREF => sub { # (nothing, but old SQLA passed it through)
335 #TODO in SQLA >= 2.0 it will die instead
336 belch "HASH ref as bind value in insert is not supported";
338 push @all_bind, $self->_bindtype($column, $v);
341 SCALARREF => sub { # literal SQL without bind
345 SCALAR_or_UNDEF => sub {
347 push @all_bind, $self->_bindtype($column, $v);
352 my $sql = join(", ", @values);
353 return ($sql, @all_bind);
358 #======================================================================
360 #======================================================================
365 my $table = $self->_table(shift);
366 my $data = shift || return;
370 # first build the 'SET' part of the sql statement
371 puke "Unsupported data type specified to \$sql->update"
372 unless ref $data eq 'HASH';
374 my ($sql, @all_bind) = $self->_update_set_values($data);
375 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
379 my($where_sql, @where_bind) = $self->where($where);
381 push @all_bind, @where_bind;
384 if ($options->{returning}) {
385 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
386 $sql .= $returning_sql;
387 push @all_bind, @returning_bind;
390 return wantarray ? ($sql, @all_bind) : $sql;
393 sub _update_set_values {
394 my ($self, $data) = @_;
396 my (@set, @all_bind);
397 for my $k (sort keys %$data) {
400 my $label = $self->_quote($k);
402 $self->_SWITCH_refkind($v, {
404 if ($self->{array_datatypes}) { # array datatype
405 push @set, "$label = ?";
406 push @all_bind, $self->_bindtype($k, $v);
408 else { # literal SQL with bind
409 my ($sql, @bind) = @$v;
410 $self->_assert_bindval_matches_bindtype(@bind);
411 push @set, "$label = $sql";
412 push @all_bind, @bind;
415 ARRAYREFREF => sub { # literal SQL with bind
416 my ($sql, @bind) = @${$v};
417 $self->_assert_bindval_matches_bindtype(@bind);
418 push @set, "$label = $sql";
419 push @all_bind, @bind;
421 SCALARREF => sub { # literal SQL without bind
422 push @set, "$label = $$v";
425 my ($op, $arg, @rest) = %$v;
427 puke 'Operator calls in update must be in the form { -op => $arg }'
428 if (@rest or not $op =~ /^\-(.+)/);
430 local $self->{_nested_func_lhs} = $k;
431 my ($sql, @bind) = $self->_where_unary_op($1, $arg);
433 push @set, "$label = $sql";
434 push @all_bind, @bind;
436 SCALAR_or_UNDEF => sub {
437 push @set, "$label = ?";
438 push @all_bind, $self->_bindtype($k, $v);
444 my $sql = join ', ', @set;
446 return ($sql, @all_bind);
449 # So that subclasses can override UPDATE ... RETURNING separately from
451 sub _update_returning { shift->_returning(@_) }
455 #======================================================================
457 #======================================================================
462 my $table = $self->_table(shift);
463 my $fields = shift || '*';
467 my($where_sql, @bind) = $self->where($where, $order);
469 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
471 my $sql = join(' ', $self->_sqlcase('select'), $f,
472 $self->_sqlcase('from'), $table)
475 return wantarray ? ($sql, @bind) : $sql;
478 #======================================================================
480 #======================================================================
485 my $table = $self->_table(shift);
489 my($where_sql, @bind) = $self->where($where);
490 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
492 if ($options->{returning}) {
493 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
494 $sql .= $returning_sql;
495 push @bind, @returning_bind;
498 return wantarray ? ($sql, @bind) : $sql;
501 # So that subclasses can override DELETE ... RETURNING separately from
503 sub _delete_returning { shift->_returning(@_) }
507 #======================================================================
509 #======================================================================
513 # Finally, a separate routine just to handle WHERE clauses
515 my ($self, $where, $order) = @_;
518 my ($sql, @bind) = $self->_recurse_where($where);
519 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
523 my ($order_sql, @order_bind) = $self->_order_by($order);
525 push @bind, @order_bind;
528 return wantarray ? ($sql, @bind) : $sql;
533 my ($self, $where, $logic) = @_;
535 # dispatch on appropriate method according to refkind of $where
536 my $method = $self->_METHOD_FOR_refkind("_where", $where);
538 my ($sql, @bind) = $self->$method($where, $logic);
540 # DBIx::Class used to call _recurse_where in scalar context
541 # something else might too...
543 return ($sql, @bind);
546 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
553 #======================================================================
554 # WHERE: top-level ARRAYREF
555 #======================================================================
558 sub _where_ARRAYREF {
559 my ($self, $where, $logic) = @_;
561 $logic = uc($logic || $self->{logic});
562 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
564 my @clauses = @$where;
566 my (@sql_clauses, @all_bind);
567 # need to use while() so can shift() for pairs
569 my $el = shift @clauses;
571 $el = undef if (defined $el and ! length $el);
573 # switch according to kind of $el and get corresponding ($sql, @bind)
574 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
576 # skip empty elements, otherwise get invalid trailing AND stuff
577 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
581 $self->_assert_bindval_matches_bindtype(@b);
585 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
587 SCALARREF => sub { ($$el); },
590 # top-level arrayref with scalars, recurse in pairs
591 $self->_recurse_where({$el => shift(@clauses)})
594 UNDEF => sub {puke "Supplying an empty left hand side argument is not supported in array-pairs" },
598 push @sql_clauses, $sql;
599 push @all_bind, @bind;
603 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
606 #======================================================================
607 # WHERE: top-level ARRAYREFREF
608 #======================================================================
610 sub _where_ARRAYREFREF {
611 my ($self, $where) = @_;
612 my ($sql, @bind) = @$$where;
613 $self->_assert_bindval_matches_bindtype(@bind);
614 return ($sql, @bind);
617 #======================================================================
618 # WHERE: top-level HASHREF
619 #======================================================================
622 my ($self, $where) = @_;
623 my (@sql_clauses, @all_bind);
625 for my $k (sort keys %$where) {
626 my $v = $where->{$k};
628 # ($k => $v) is either a special unary op or a regular hashpair
629 my ($sql, @bind) = do {
631 # put the operator in canonical form
633 $op = substr $op, 1; # remove initial dash
634 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
635 $op =~ s/\s+/ /g; # compress whitespace
637 # so that -not_foo works correctly
638 $op =~ s/^not_/NOT /i;
640 $self->_debug("Unary OP(-$op) within hashref, recursing...");
641 my ($s, @b) = $self->_where_unary_op($op, $v);
643 # top level vs nested
644 # we assume that handled unary ops will take care of their ()s
646 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
648 ( defined $self->{_nested_func_lhs} and $self->{_nested_func_lhs} eq $k )
654 if (is_literal_value ($v) ) {
655 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
658 puke "Supplying an empty left hand side argument is not supported in hash-pairs";
662 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
663 $self->$method($k, $v);
667 push @sql_clauses, $sql;
668 push @all_bind, @bind;
671 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
674 sub _where_unary_op {
675 my ($self, $op, $rhs) = @_;
677 # top level special ops are illegal in general
678 # this includes the -ident/-value ops (dual purpose unary and special)
679 puke "Illegal use of top-level '-$op'"
680 if ! defined $self->{_nested_func_lhs} and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
682 if (my $op_entry = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
683 my $handler = $op_entry->{handler};
685 if (not ref $handler) {
686 if ($op =~ s/ [_\s]? \d+ $//x ) {
687 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
688 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
690 return $self->$handler($op, $rhs);
692 elsif (ref $handler eq 'CODE') {
693 return $handler->($self, $op, $rhs);
696 puke "Illegal handler for operator $op - expecting a method name or a coderef";
700 $self->_debug("Generic unary OP: $op - recursing as function");
702 $self->_assert_pass_injection_guard($op);
704 my ($sql, @bind) = $self->_SWITCH_refkind($rhs, {
706 puke "Illegal use of top-level '-$op'"
707 unless defined $self->{_nested_func_lhs};
710 $self->_convert('?'),
711 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
715 $self->_recurse_where($rhs)
719 $sql = sprintf('%s %s',
720 $self->_sqlcase($op),
724 return ($sql, @bind);
727 sub _where_op_ANDOR {
728 my ($self, $op, $v) = @_;
730 $self->_SWITCH_refkind($v, {
732 return $self->_where_ARRAYREF($v, $op);
736 return ($op =~ /^or/i)
737 ? $self->_where_ARRAYREF([ map { $_ => $v->{$_} } (sort keys %$v) ], $op)
738 : $self->_where_HASHREF($v);
742 puke "-$op => \\\$scalar makes little sense, use " .
744 ? '[ \$scalar, \%rest_of_conditions ] instead'
745 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
750 puke "-$op => \\[...] makes little sense, use " .
752 ? '[ \[...], \%rest_of_conditions ] instead'
753 : '-and => [ \[...], \%rest_of_conditions ] instead'
757 SCALAR => sub { # permissively interpreted as SQL
758 puke "-$op => \$value makes little sense, use -bool => \$value instead";
762 puke "-$op => undef not supported";
768 my ($self, $op, $v) = @_;
770 $self->_SWITCH_refkind($v, {
772 SCALAR => sub { # permissively interpreted as SQL
773 belch "literal SQL should be -nest => \\'scalar' "
774 . "instead of -nest => 'scalar' ";
779 puke "-$op => undef not supported";
783 $self->_recurse_where($v);
791 my ($self, $op, $v) = @_;
793 my ($s, @b) = $self->_SWITCH_refkind($v, {
794 SCALAR => sub { # interpreted as SQL column
795 $self->_convert($self->_quote($v));
799 puke "-$op => undef not supported";
803 $self->_recurse_where($v);
807 $s = "(NOT $s)" if $op =~ /^not/i;
812 sub _where_op_IDENT {
814 my ($op, $rhs) = splice @_, -2;
815 if (! defined $rhs or length ref $rhs) {
816 puke "-$op requires a single plain scalar argument (a quotable identifier)";
819 # in case we are called as a top level special op (no '=')
822 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
830 sub _where_op_VALUE {
832 my ($op, $rhs) = splice @_, -2;
834 # in case we are called as a top level special op (no '=')
838 if (! defined $rhs) {
840 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
847 (defined $lhs ? $lhs : $self->{_nested_func_lhs}),
854 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
858 $self->_convert('?'),
864 sub _where_hashpair_ARRAYREF {
865 my ($self, $k, $v) = @_;
868 my @v = @$v; # need copy because of shift below
869 $self->_debug("ARRAY($k) means distribute over elements");
871 # put apart first element if it is an operator (-and, -or)
873 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
877 my @distributed = map { {$k => $_} } @v;
880 $self->_debug("OP($op) reinjected into the distributed array");
881 unshift @distributed, $op;
884 my $logic = $op ? substr($op, 1) : '';
886 return $self->_recurse_where(\@distributed, $logic);
889 $self->_debug("empty ARRAY($k) means 0=1");
890 return ($self->{sqlfalse});
894 sub _where_hashpair_HASHREF {
895 my ($self, $k, $v, $logic) = @_;
898 local $self->{_nested_func_lhs} = defined $self->{_nested_func_lhs}
899 ? $self->{_nested_func_lhs}
903 my ($all_sql, @all_bind);
905 for my $orig_op (sort keys %$v) {
906 my $val = $v->{$orig_op};
908 # put the operator in canonical form
911 # FIXME - we need to phase out dash-less ops
912 $op =~ s/^-//; # remove possible initial dash
913 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
914 $op =~ s/\s+/ /g; # compress whitespace
916 $self->_assert_pass_injection_guard($op);
919 $op =~ s/^is_not/IS NOT/i;
921 # so that -not_foo works correctly
922 $op =~ s/^not_/NOT /i;
924 # another retarded special case: foo => { $op => { -value => undef } }
925 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
931 # CASE: col-value logic modifiers
932 if ($orig_op =~ /^ \- (and|or) $/xi) {
933 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
935 # CASE: special operators like -in or -between
936 elsif (my $special_op = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
937 my $handler = $special_op->{handler};
939 puke "No handler supplied for special operator $orig_op";
941 elsif (not ref $handler) {
942 ($sql, @bind) = $self->$handler($k, $op, $val);
944 elsif (ref $handler eq 'CODE') {
945 ($sql, @bind) = $handler->($self, $k, $op, $val);
948 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
952 $self->_SWITCH_refkind($val, {
954 ARRAYREF => sub { # CASE: col => {op => \@vals}
955 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
958 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
959 my ($sub_sql, @sub_bind) = @$$val;
960 $self->_assert_bindval_matches_bindtype(@sub_bind);
961 $sql = join ' ', $self->_convert($self->_quote($k)),
962 $self->_sqlcase($op),
967 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
969 $op =~ /^not$/i ? 'is not' # legacy
970 : $op =~ $self->{equality_op} ? 'is'
971 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
972 : $op =~ $self->{inequality_op} ? 'is not'
973 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
974 : puke "unexpected operator '$orig_op' with undef operand";
976 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
979 FALLBACK => sub { # CASE: col => {op/func => $stuff}
980 ($sql, @bind) = $self->_where_unary_op($op, $val);
983 $self->_convert($self->_quote($k)),
984 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
990 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
991 push @all_bind, @bind;
993 return ($all_sql, @all_bind);
996 sub _where_field_IS {
997 my ($self, $k, $op, $v) = @_;
999 my ($s) = $self->_SWITCH_refkind($v, {
1002 $self->_convert($self->_quote($k)),
1003 map { $self->_sqlcase($_)} ($op, 'null')
1006 puke "$op can only take undef as argument";
1013 sub _where_field_op_ARRAYREF {
1014 my ($self, $k, $op, $vals) = @_;
1016 my @vals = @$vals; #always work on a copy
1019 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
1021 join(', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
1024 # see if the first element is an -and/-or op
1026 if (defined $vals[0] && $vals[0] =~ /^ - (AND|OR) $/ix) {
1031 # a long standing API wart - an attempt to change this behavior during
1032 # the 1.50 series failed *spectacularly*. Warn instead and leave the
1037 (!$logic or $logic eq 'OR')
1039 ($op =~ $self->{inequality_op} or $op =~ $self->{not_like_op})
1042 belch "A multi-element arrayref as an argument to the inequality op '$o' "
1043 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
1044 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
1048 # distribute $op over each remaining member of @vals, append logic if exists
1049 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
1053 # try to DWIM on equality operators
1055 $op =~ $self->{equality_op} ? $self->{sqlfalse}
1056 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
1057 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
1058 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
1059 : puke "operator '$op' applied on an empty array (field '$k')";
1064 sub _where_hashpair_SCALARREF {
1065 my ($self, $k, $v) = @_;
1066 $self->_debug("SCALAR($k) means literal SQL: $$v");
1067 my $sql = $self->_quote($k) . " " . $$v;
1071 # literal SQL with bind
1072 sub _where_hashpair_ARRAYREFREF {
1073 my ($self, $k, $v) = @_;
1074 $self->_debug("REF($k) means literal SQL: @${$v}");
1075 my ($sql, @bind) = @$$v;
1076 $self->_assert_bindval_matches_bindtype(@bind);
1077 $sql = $self->_quote($k) . " " . $sql;
1078 return ($sql, @bind );
1081 # literal SQL without bind
1082 sub _where_hashpair_SCALAR {
1083 my ($self, $k, $v) = @_;
1084 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
1085 my $sql = join ' ', $self->_convert($self->_quote($k)),
1086 $self->_sqlcase($self->{cmp}),
1087 $self->_convert('?');
1088 my @bind = $self->_bindtype($k, $v);
1089 return ($sql, @bind);
1093 sub _where_hashpair_UNDEF {
1094 my ($self, $k, $v) = @_;
1095 $self->_debug("UNDEF($k) means IS NULL");
1096 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
1100 #======================================================================
1101 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
1102 #======================================================================
1105 sub _where_SCALARREF {
1106 my ($self, $where) = @_;
1109 $self->_debug("SCALAR(*top) means literal SQL: $$where");
1115 my ($self, $where) = @_;
1118 $self->_debug("NOREF(*top) means literal SQL: $where");
1129 #======================================================================
1130 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
1131 #======================================================================
1134 sub _where_field_BETWEEN {
1135 my ($self, $k, $op, $vals) = @_;
1137 my ($label, $and, $placeholder);
1138 $label = $self->_convert($self->_quote($k));
1139 $and = ' ' . $self->_sqlcase('and') . ' ';
1140 $placeholder = $self->_convert('?');
1141 $op = $self->_sqlcase($op);
1143 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1145 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1146 ARRAYREFREF => sub {
1147 my ($s, @b) = @$$vals;
1148 $self->_assert_bindval_matches_bindtype(@b);
1155 puke $invalid_args if @$vals != 2;
1157 my (@all_sql, @all_bind);
1158 foreach my $val (@$vals) {
1159 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1161 return ($placeholder, $self->_bindtype($k, $val) );
1166 ARRAYREFREF => sub {
1167 my ($sql, @bind) = @$$val;
1168 $self->_assert_bindval_matches_bindtype(@bind);
1169 return ($sql, @bind);
1172 my ($func, $arg, @rest) = %$val;
1173 puke "Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN"
1174 if (@rest or $func !~ /^ \- (.+)/x);
1175 $self->_where_unary_op($1 => $arg);
1181 push @all_sql, $sql;
1182 push @all_bind, @bind;
1186 (join $and, @all_sql),
1195 my $sql = "( $label $op $clause )";
1196 return ($sql, @bind)
1200 sub _where_field_IN {
1201 my ($self, $k, $op, $vals) = @_;
1203 # backwards compatibility: if scalar, force into an arrayref
1204 $vals = [$vals] if defined $vals && ! ref $vals;
1206 my ($label) = $self->_convert($self->_quote($k));
1207 my ($placeholder) = $self->_convert('?');
1208 $op = $self->_sqlcase($op);
1210 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1211 ARRAYREF => sub { # list of choices
1212 if (@$vals) { # nonempty list
1213 my (@all_sql, @all_bind);
1215 for my $val (@$vals) {
1216 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1218 return ($placeholder, $val);
1223 ARRAYREFREF => sub {
1224 my ($sql, @bind) = @$$val;
1225 $self->_assert_bindval_matches_bindtype(@bind);
1226 return ($sql, @bind);
1229 my ($func, $arg, @rest) = %$val;
1230 puke "Only simple { -func => arg } functions accepted as sub-arguments to IN"
1231 if (@rest or $func !~ /^ \- (.+)/x);
1232 $self->_where_unary_op($1 => $arg);
1236 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1237 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1238 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1239 . 'will emit the logically correct SQL instead of raising this exception)'
1243 push @all_sql, $sql;
1244 push @all_bind, @bind;
1248 sprintf('%s %s ( %s )',
1251 join(', ', @all_sql)
1253 $self->_bindtype($k, @all_bind),
1256 else { # empty list: some databases won't understand "IN ()", so DWIM
1257 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1262 SCALARREF => sub { # literal SQL
1263 my $sql = $self->_open_outer_paren($$vals);
1264 return ("$label $op ( $sql )");
1266 ARRAYREFREF => sub { # literal SQL with bind
1267 my ($sql, @bind) = @$$vals;
1268 $self->_assert_bindval_matches_bindtype(@bind);
1269 $sql = $self->_open_outer_paren($sql);
1270 return ("$label $op ( $sql )", @bind);
1274 puke "Argument passed to the '$op' operator can not be undefined";
1278 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1282 return ($sql, @bind);
1285 # Some databases (SQLite) treat col IN (1, 2) different from
1286 # col IN ( (1, 2) ). Use this to strip all outer parens while
1287 # adding them back in the corresponding method
1288 sub _open_outer_paren {
1289 my ($self, $sql) = @_;
1291 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1293 # there are closing parens inside, need the heavy duty machinery
1294 # to reevaluate the extraction starting from $sql (full reevaluation)
1295 if ($inner =~ /\)/) {
1296 require Text::Balanced;
1298 my (undef, $remainder) = do {
1299 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1301 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1304 # the entire expression needs to be a balanced bracketed thing
1305 # (after an extract no remainder sans trailing space)
1306 last if defined $remainder and $remainder =~ /\S/;
1316 #======================================================================
1318 #======================================================================
1321 my ($self, $arg) = @_;
1324 for my $c ($self->_order_by_chunks($arg) ) {
1325 $self->_SWITCH_refkind($c, {
1326 SCALAR => sub { push @sql, $c },
1327 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1333 $self->_sqlcase(' order by'),
1339 return wantarray ? ($sql, @bind) : $sql;
1342 sub _order_by_chunks {
1343 my ($self, $arg) = @_;
1345 return $self->_SWITCH_refkind($arg, {
1348 map { $self->_order_by_chunks($_ ) } @$arg;
1351 ARRAYREFREF => sub {
1352 my ($s, @b) = @$$arg;
1353 $self->_assert_bindval_matches_bindtype(@b);
1357 SCALAR => sub {$self->_quote($arg)},
1359 UNDEF => sub {return () },
1361 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1364 # get first pair in hash
1365 my ($key, $val, @rest) = %$arg;
1367 return () unless $key;
1369 if (@rest or not $key =~ /^-(desc|asc)/i) {
1370 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1376 for my $c ($self->_order_by_chunks($val)) {
1379 $self->_SWITCH_refkind($c, {
1384 ($sql, @bind) = @$c;
1388 $sql = $sql . ' ' . $self->_sqlcase($direction);
1390 push @ret, [ $sql, @bind];
1399 #======================================================================
1400 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1401 #======================================================================
1406 $self->_SWITCH_refkind($from, {
1407 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1408 SCALAR => sub {$self->_quote($from)},
1409 SCALARREF => sub {$$from},
1414 #======================================================================
1416 #======================================================================
1418 # highly optimized, as it's called way too often
1420 # my ($self, $label) = @_;
1422 return '' unless defined $_[1];
1423 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1425 $_[0]->{quote_char} or
1426 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1428 my $qref = ref $_[0]->{quote_char};
1430 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1431 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1432 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1434 my $esc = $_[0]->{escape_char} || $r;
1436 # parts containing * are naturally unquoted
1437 return join($_[0]->{name_sep}||'', map
1438 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1439 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1444 # Conversion, if applicable
1446 #my ($self, $arg) = @_;
1447 if ($_[0]->{convert}) {
1448 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1455 #my ($self, $col, @vals) = @_;
1456 # called often - tighten code
1457 return $_[0]->{bindtype} eq 'columns'
1458 ? map {[$_[1], $_]} @_[2 .. $#_]
1463 # Dies if any element of @bind is not in [colname => value] format
1464 # if bindtype is 'columns'.
1465 sub _assert_bindval_matches_bindtype {
1466 # my ($self, @bind) = @_;
1468 if ($self->{bindtype} eq 'columns') {
1470 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1471 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1477 sub _join_sql_clauses {
1478 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1480 if (@$clauses_aref > 1) {
1481 my $join = " " . $self->_sqlcase($logic) . " ";
1482 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1483 return ($sql, @$bind_aref);
1485 elsif (@$clauses_aref) {
1486 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1489 return (); # if no SQL, ignore @$bind_aref
1494 # Fix SQL case, if so requested
1496 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1497 # don't touch the argument ... crooked logic, but let's not change it!
1498 return $_[0]->{case} ? $_[1] : uc($_[1]);
1502 #======================================================================
1503 # DISPATCHING FROM REFKIND
1504 #======================================================================
1507 my ($self, $data) = @_;
1509 return 'UNDEF' unless defined $data;
1511 # blessed objects are treated like scalars
1512 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1514 return 'SCALAR' unless $ref;
1517 while ($ref eq 'REF') {
1519 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1523 return ($ref||'SCALAR') . ('REF' x $n_steps);
1527 my ($self, $data) = @_;
1528 my @try = ($self->_refkind($data));
1529 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1530 push @try, 'FALLBACK';
1534 sub _METHOD_FOR_refkind {
1535 my ($self, $meth_prefix, $data) = @_;
1538 for (@{$self->_try_refkind($data)}) {
1539 $method = $self->can($meth_prefix."_".$_)
1543 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1547 sub _SWITCH_refkind {
1548 my ($self, $data, $dispatch_table) = @_;
1551 for (@{$self->_try_refkind($data)}) {
1552 $coderef = $dispatch_table->{$_}
1556 puke "no dispatch entry for ".$self->_refkind($data)
1565 #======================================================================
1566 # VALUES, GENERATE, AUTOLOAD
1567 #======================================================================
1569 # LDNOTE: original code from nwiger, didn't touch code in that section
1570 # I feel the AUTOLOAD stuff should not be the default, it should
1571 # only be activated on explicit demand by user.
1575 my $data = shift || return;
1576 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1577 unless ref $data eq 'HASH';
1580 foreach my $k (sort keys %$data) {
1581 my $v = $data->{$k};
1582 $self->_SWITCH_refkind($v, {
1584 if ($self->{array_datatypes}) { # array datatype
1585 push @all_bind, $self->_bindtype($k, $v);
1587 else { # literal SQL with bind
1588 my ($sql, @bind) = @$v;
1589 $self->_assert_bindval_matches_bindtype(@bind);
1590 push @all_bind, @bind;
1593 ARRAYREFREF => sub { # literal SQL with bind
1594 my ($sql, @bind) = @${$v};
1595 $self->_assert_bindval_matches_bindtype(@bind);
1596 push @all_bind, @bind;
1598 SCALARREF => sub { # literal SQL without bind
1600 SCALAR_or_UNDEF => sub {
1601 push @all_bind, $self->_bindtype($k, $v);
1612 my(@sql, @sqlq, @sqlv);
1616 if ($ref eq 'HASH') {
1617 for my $k (sort keys %$_) {
1620 my $label = $self->_quote($k);
1621 if ($r eq 'ARRAY') {
1622 # literal SQL with bind
1623 my ($sql, @bind) = @$v;
1624 $self->_assert_bindval_matches_bindtype(@bind);
1625 push @sqlq, "$label = $sql";
1627 } elsif ($r eq 'SCALAR') {
1628 # literal SQL without bind
1629 push @sqlq, "$label = $$v";
1631 push @sqlq, "$label = ?";
1632 push @sqlv, $self->_bindtype($k, $v);
1635 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1636 } elsif ($ref eq 'ARRAY') {
1637 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1640 if ($r eq 'ARRAY') { # literal SQL with bind
1641 my ($sql, @bind) = @$v;
1642 $self->_assert_bindval_matches_bindtype(@bind);
1645 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1646 # embedded literal SQL
1653 push @sql, '(' . join(', ', @sqlq) . ')';
1654 } elsif ($ref eq 'SCALAR') {
1658 # strings get case twiddled
1659 push @sql, $self->_sqlcase($_);
1663 my $sql = join ' ', @sql;
1665 # this is pretty tricky
1666 # if ask for an array, return ($stmt, @bind)
1667 # otherwise, s/?/shift @sqlv/ to put it inline
1669 return ($sql, @sqlv);
1671 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1672 ref $d ? $d->[1] : $d/e;
1681 # This allows us to check for a local, then _form, attr
1683 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1684 return $self->generate($name, @_);
1695 SQL::Abstract - Generate SQL from Perl data structures
1701 my $sql = SQL::Abstract->new;
1703 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1705 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1707 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1709 my($stmt, @bind) = $sql->delete($table, \%where);
1711 # Then, use these in your DBI statements
1712 my $sth = $dbh->prepare($stmt);
1713 $sth->execute(@bind);
1715 # Just generate the WHERE clause
1716 my($stmt, @bind) = $sql->where(\%where, $order);
1718 # Return values in the same order, for hashed queries
1719 # See PERFORMANCE section for more details
1720 my @bind = $sql->values(\%fieldvals);
1724 This module was inspired by the excellent L<DBIx::Abstract>.
1725 However, in using that module I found that what I really wanted
1726 to do was generate SQL, but still retain complete control over my
1727 statement handles and use the DBI interface. So, I set out to
1728 create an abstract SQL generation module.
1730 While based on the concepts used by L<DBIx::Abstract>, there are
1731 several important differences, especially when it comes to WHERE
1732 clauses. I have modified the concepts used to make the SQL easier
1733 to generate from Perl data structures and, IMO, more intuitive.
1734 The underlying idea is for this module to do what you mean, based
1735 on the data structures you provide it. The big advantage is that
1736 you don't have to modify your code every time your data changes,
1737 as this module figures it out.
1739 To begin with, an SQL INSERT is as easy as just specifying a hash
1740 of C<key=value> pairs:
1743 name => 'Jimbo Bobson',
1744 phone => '123-456-7890',
1745 address => '42 Sister Lane',
1746 city => 'St. Louis',
1747 state => 'Louisiana',
1750 The SQL can then be generated with this:
1752 my($stmt, @bind) = $sql->insert('people', \%data);
1754 Which would give you something like this:
1756 $stmt = "INSERT INTO people
1757 (address, city, name, phone, state)
1758 VALUES (?, ?, ?, ?, ?)";
1759 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1760 '123-456-7890', 'Louisiana');
1762 These are then used directly in your DBI code:
1764 my $sth = $dbh->prepare($stmt);
1765 $sth->execute(@bind);
1767 =head2 Inserting and Updating Arrays
1769 If your database has array types (like for example Postgres),
1770 activate the special option C<< array_datatypes => 1 >>
1771 when creating the C<SQL::Abstract> object.
1772 Then you may use an arrayref to insert and update database array types:
1774 my $sql = SQL::Abstract->new(array_datatypes => 1);
1776 planets => [qw/Mercury Venus Earth Mars/]
1779 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1783 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1785 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1788 =head2 Inserting and Updating SQL
1790 In order to apply SQL functions to elements of your C<%data> you may
1791 specify a reference to an arrayref for the given hash value. For example,
1792 if you need to execute the Oracle C<to_date> function on a value, you can
1793 say something like this:
1797 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1800 The first value in the array is the actual SQL. Any other values are
1801 optional and would be included in the bind values array. This gives
1804 my($stmt, @bind) = $sql->insert('people', \%data);
1806 $stmt = "INSERT INTO people (name, date_entered)
1807 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1808 @bind = ('Bill', '03/02/2003');
1810 An UPDATE is just as easy, all you change is the name of the function:
1812 my($stmt, @bind) = $sql->update('people', \%data);
1814 Notice that your C<%data> isn't touched; the module will generate
1815 the appropriately quirky SQL for you automatically. Usually you'll
1816 want to specify a WHERE clause for your UPDATE, though, which is
1817 where handling C<%where> hashes comes in handy...
1819 =head2 Complex where statements
1821 This module can generate pretty complicated WHERE statements
1822 easily. For example, simple C<key=value> pairs are taken to mean
1823 equality, and if you want to see if a field is within a set
1824 of values, you can use an arrayref. Let's say we wanted to
1825 SELECT some data based on this criteria:
1828 requestor => 'inna',
1829 worker => ['nwiger', 'rcwe', 'sfz'],
1830 status => { '!=', 'completed' }
1833 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1835 The above would give you something like this:
1837 $stmt = "SELECT * FROM tickets WHERE
1838 ( requestor = ? ) AND ( status != ? )
1839 AND ( worker = ? OR worker = ? OR worker = ? )";
1840 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1842 Which you could then use in DBI code like so:
1844 my $sth = $dbh->prepare($stmt);
1845 $sth->execute(@bind);
1851 The methods are simple. There's one for every major SQL operation,
1852 and a constructor you use first. The arguments are specified in a
1853 similar order for each method (table, then fields, then a where
1854 clause) to try and simplify things.
1856 =head2 new(option => 'value')
1858 The C<new()> function takes a list of options and values, and returns
1859 a new B<SQL::Abstract> object which can then be used to generate SQL
1860 through the methods below. The options accepted are:
1866 If set to 'lower', then SQL will be generated in all lowercase. By
1867 default SQL is generated in "textbook" case meaning something like:
1869 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1871 Any setting other than 'lower' is ignored.
1875 This determines what the default comparison operator is. By default
1876 it is C<=>, meaning that a hash like this:
1878 %where = (name => 'nwiger', email => 'nate@wiger.org');
1880 Will generate SQL like this:
1882 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1884 However, you may want loose comparisons by default, so if you set
1885 C<cmp> to C<like> you would get SQL such as:
1887 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1889 You can also override the comparison on an individual basis - see
1890 the huge section on L</"WHERE CLAUSES"> at the bottom.
1892 =item sqltrue, sqlfalse
1894 Expressions for inserting boolean values within SQL statements.
1895 By default these are C<1=1> and C<1=0>. They are used
1896 by the special operators C<-in> and C<-not_in> for generating
1897 correct SQL even when the argument is an empty array (see below).
1901 This determines the default logical operator for multiple WHERE
1902 statements in arrays or hashes. If absent, the default logic is "or"
1903 for arrays, and "and" for hashes. This means that a WHERE
1907 event_date => {'>=', '2/13/99'},
1908 event_date => {'<=', '4/24/03'},
1911 will generate SQL like this:
1913 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1915 This is probably not what you want given this query, though (look
1916 at the dates). To change the "OR" to an "AND", simply specify:
1918 my $sql = SQL::Abstract->new(logic => 'and');
1920 Which will change the above C<WHERE> to:
1922 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1924 The logic can also be changed locally by inserting
1925 a modifier in front of an arrayref:
1927 @where = (-and => [event_date => {'>=', '2/13/99'},
1928 event_date => {'<=', '4/24/03'} ]);
1930 See the L</"WHERE CLAUSES"> section for explanations.
1934 This will automatically convert comparisons using the specified SQL
1935 function for both column and value. This is mostly used with an argument
1936 of C<upper> or C<lower>, so that the SQL will have the effect of
1937 case-insensitive "searches". For example, this:
1939 $sql = SQL::Abstract->new(convert => 'upper');
1940 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1942 Will turn out the following SQL:
1944 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1946 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1947 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1948 not validate this option; it will just pass through what you specify verbatim).
1952 This is a kludge because many databases suck. For example, you can't
1953 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1954 Instead, you have to use C<bind_param()>:
1956 $sth->bind_param(1, 'reg data');
1957 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1959 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1960 which loses track of which field each slot refers to. Fear not.
1962 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1963 Currently, you can specify either C<normal> (default) or C<columns>. If you
1964 specify C<columns>, you will get an array that looks like this:
1966 my $sql = SQL::Abstract->new(bindtype => 'columns');
1967 my($stmt, @bind) = $sql->insert(...);
1970 [ 'column1', 'value1' ],
1971 [ 'column2', 'value2' ],
1972 [ 'column3', 'value3' ],
1975 You can then iterate through this manually, using DBI's C<bind_param()>.
1977 $sth->prepare($stmt);
1980 my($col, $data) = @$_;
1981 if ($col eq 'details' || $col eq 'comments') {
1982 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1983 } elsif ($col eq 'image') {
1984 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1986 $sth->bind_param($i, $data);
1990 $sth->execute; # execute without @bind now
1992 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1993 Basically, the advantage is still that you don't have to care which fields
1994 are or are not included. You could wrap that above C<for> loop in a simple
1995 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1996 get a layer of abstraction over manual SQL specification.
1998 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1999 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
2000 will expect the bind values in this format.
2004 This is the character that a table or column name will be quoted
2005 with. By default this is an empty string, but you could set it to
2006 the character C<`>, to generate SQL like this:
2008 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
2010 Alternatively, you can supply an array ref of two items, the first being the left
2011 hand quote character, and the second the right hand quote character. For
2012 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
2013 that generates SQL like this:
2015 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
2017 Quoting is useful if you have tables or columns names that are reserved
2018 words in your database's SQL dialect.
2022 This is the character that will be used to escape L</quote_char>s appearing
2023 in an identifier before it has been quoted.
2025 The parameter default in case of a single L</quote_char> character is the quote
2028 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
2029 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
2030 of the B<opening (left)> L</quote_char> within the identifier are currently left
2031 untouched. The default for opening-closing-style quotes may change in future
2032 versions, thus you are B<strongly encouraged> to specify the escape character
2037 This is the character that separates a table and column name. It is
2038 necessary to specify this when the C<quote_char> option is selected,
2039 so that tables and column names can be individually quoted like this:
2041 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
2043 =item injection_guard
2045 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
2046 column name specified in a query structure. This is a safety mechanism to avoid
2047 injection attacks when mishandling user input e.g.:
2049 my %condition_as_column_value_pairs = get_values_from_user();
2050 $sqla->select( ... , \%condition_as_column_value_pairs );
2052 If the expression matches an exception is thrown. Note that literal SQL
2053 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
2055 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
2057 =item array_datatypes
2059 When this option is true, arrayrefs in INSERT or UPDATE are
2060 interpreted as array datatypes and are passed directly
2062 When this option is false, arrayrefs are interpreted
2063 as literal SQL, just like refs to arrayrefs
2064 (but this behavior is for backwards compatibility; when writing
2065 new queries, use the "reference to arrayref" syntax
2071 Takes a reference to a list of "special operators"
2072 to extend the syntax understood by L<SQL::Abstract>.
2073 See section L</"SPECIAL OPERATORS"> for details.
2077 Takes a reference to a list of "unary operators"
2078 to extend the syntax understood by L<SQL::Abstract>.
2079 See section L</"UNARY OPERATORS"> for details.
2085 =head2 insert($table, \@values || \%fieldvals, \%options)
2087 This is the simplest function. You simply give it a table name
2088 and either an arrayref of values or hashref of field/value pairs.
2089 It returns an SQL INSERT statement and a list of bind values.
2090 See the sections on L</"Inserting and Updating Arrays"> and
2091 L</"Inserting and Updating SQL"> for information on how to insert
2092 with those data types.
2094 The optional C<\%options> hash reference may contain additional
2095 options to generate the insert SQL. Currently supported options
2102 Takes either a scalar of raw SQL fields, or an array reference of
2103 field names, and adds on an SQL C<RETURNING> statement at the end.
2104 This allows you to return data generated by the insert statement
2105 (such as row IDs) without performing another C<SELECT> statement.
2106 Note, however, this is not part of the SQL standard and may not
2107 be supported by all database engines.
2111 =head2 update($table, \%fieldvals, \%where, \%options)
2113 This takes a table, hashref of field/value pairs, and an optional
2114 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
2116 See the sections on L</"Inserting and Updating Arrays"> and
2117 L</"Inserting and Updating SQL"> for information on how to insert
2118 with those data types.
2120 The optional C<\%options> hash reference may contain additional
2121 options to generate the update SQL. Currently supported options
2128 See the C<returning> option to
2129 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2133 =head2 select($source, $fields, $where, $order)
2135 This returns a SQL SELECT statement and associated list of bind values, as
2136 specified by the arguments:
2142 Specification of the 'FROM' part of the statement.
2143 The argument can be either a plain scalar (interpreted as a table
2144 name, will be quoted), or an arrayref (interpreted as a list
2145 of table names, joined by commas, quoted), or a scalarref
2146 (literal SQL, not quoted).
2150 Specification of the list of fields to retrieve from
2152 The argument can be either an arrayref (interpreted as a list
2153 of field names, will be joined by commas and quoted), or a
2154 plain scalar (literal SQL, not quoted).
2155 Please observe that this API is not as flexible as that of
2156 the first argument C<$source>, for backwards compatibility reasons.
2160 Optional argument to specify the WHERE part of the query.
2161 The argument is most often a hashref, but can also be
2162 an arrayref or plain scalar --
2163 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2167 Optional argument to specify the ORDER BY part of the query.
2168 The argument can be a scalar, a hashref or an arrayref
2169 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2175 =head2 delete($table, \%where, \%options)
2177 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2178 It returns an SQL DELETE statement and list of bind values.
2180 The optional C<\%options> hash reference may contain additional
2181 options to generate the delete SQL. Currently supported options
2188 See the C<returning> option to
2189 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2193 =head2 where(\%where, $order)
2195 This is used to generate just the WHERE clause. For example,
2196 if you have an arbitrary data structure and know what the
2197 rest of your SQL is going to look like, but want an easy way
2198 to produce a WHERE clause, use this. It returns an SQL WHERE
2199 clause and list of bind values.
2202 =head2 values(\%data)
2204 This just returns the values from the hash C<%data>, in the same
2205 order that would be returned from any of the other above queries.
2206 Using this allows you to markedly speed up your queries if you
2207 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2209 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2211 Warning: This is an experimental method and subject to change.
2213 This returns arbitrarily generated SQL. It's a really basic shortcut.
2214 It will return two different things, depending on return context:
2216 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2217 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2219 These would return the following:
2221 # First calling form
2222 $stmt = "CREATE TABLE test (?, ?)";
2223 @bind = (field1, field2);
2225 # Second calling form
2226 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2228 Depending on what you're trying to do, it's up to you to choose the correct
2229 format. In this example, the second form is what you would want.
2233 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2237 ALTER SESSION SET nls_date_format = 'MM/YY'
2239 You get the idea. Strings get their case twiddled, but everything
2240 else remains verbatim.
2242 =head1 EXPORTABLE FUNCTIONS
2244 =head2 is_plain_value
2246 Determines if the supplied argument is a plain value as understood by this
2251 =item * The value is C<undef>
2253 =item * The value is a non-reference
2255 =item * The value is an object with stringification overloading
2257 =item * The value is of the form C<< { -value => $anything } >>
2261 On failure returns C<undef>, on success returns a B<scalar> reference
2262 to the original supplied argument.
2268 The stringification overloading detection is rather advanced: it takes
2269 into consideration not only the presence of a C<""> overload, but if that
2270 fails also checks for enabled
2271 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2272 on either C<0+> or C<bool>.
2274 Unfortunately testing in the field indicates that this
2275 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2276 but only when very large numbers of stringifying objects are involved.
2277 At the time of writing ( Sep 2014 ) there is no clear explanation of
2278 the direct cause, nor is there a manageably small test case that reliably
2279 reproduces the problem.
2281 If you encounter any of the following exceptions in B<random places within
2282 your application stack> - this module may be to blame:
2284 Operation "ne": no method found,
2285 left argument in overloaded package <something>,
2286 right argument in overloaded package <something>
2290 Stub found while resolving method "???" overloading """" in package <something>
2292 If you fall victim to the above - please attempt to reduce the problem
2293 to something that could be sent to the L<SQL::Abstract developers
2294 |DBIx::Class/GETTING HELP/SUPPORT>
2295 (either publicly or privately). As a workaround in the meantime you can
2296 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2297 value, which will most likely eliminate your problem (at the expense of
2298 not being able to properly detect exotic forms of stringification).
2300 This notice and environment variable will be removed in a future version,
2301 as soon as the underlying problem is found and a reliable workaround is
2306 =head2 is_literal_value
2308 Determines if the supplied argument is a literal value as understood by this
2313 =item * C<\$sql_string>
2315 =item * C<\[ $sql_string, @bind_values ]>
2319 On failure returns C<undef>, on success returns an B<array> reference
2320 containing the unpacked version of the supplied literal SQL and bind values.
2322 =head1 WHERE CLAUSES
2326 This module uses a variation on the idea from L<DBIx::Abstract>. It
2327 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2328 module is that things in arrays are OR'ed, and things in hashes
2331 The easiest way to explain is to show lots of examples. After
2332 each C<%where> hash shown, it is assumed you used:
2334 my($stmt, @bind) = $sql->where(\%where);
2336 However, note that the C<%where> hash can be used directly in any
2337 of the other functions as well, as described above.
2339 =head2 Key-value pairs
2341 So, let's get started. To begin, a simple hash:
2345 status => 'completed'
2348 Is converted to SQL C<key = val> statements:
2350 $stmt = "WHERE user = ? AND status = ?";
2351 @bind = ('nwiger', 'completed');
2353 One common thing I end up doing is having a list of values that
2354 a field can be in. To do this, simply specify a list inside of
2359 status => ['assigned', 'in-progress', 'pending'];
2362 This simple code will create the following:
2364 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2365 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2367 A field associated to an empty arrayref will be considered a
2368 logical false and will generate 0=1.
2370 =head2 Tests for NULL values
2372 If the value part is C<undef> then this is converted to SQL <IS NULL>
2381 $stmt = "WHERE user = ? AND status IS NULL";
2384 To test if a column IS NOT NULL:
2388 status => { '!=', undef },
2391 =head2 Specific comparison operators
2393 If you want to specify a different type of operator for your comparison,
2394 you can use a hashref for a given column:
2398 status => { '!=', 'completed' }
2401 Which would generate:
2403 $stmt = "WHERE user = ? AND status != ?";
2404 @bind = ('nwiger', 'completed');
2406 To test against multiple values, just enclose the values in an arrayref:
2408 status => { '=', ['assigned', 'in-progress', 'pending'] };
2410 Which would give you:
2412 "WHERE status = ? OR status = ? OR status = ?"
2415 The hashref can also contain multiple pairs, in which case it is expanded
2416 into an C<AND> of its elements:
2420 status => { '!=', 'completed', -not_like => 'pending%' }
2423 # Or more dynamically, like from a form
2424 $where{user} = 'nwiger';
2425 $where{status}{'!='} = 'completed';
2426 $where{status}{'-not_like'} = 'pending%';
2428 # Both generate this
2429 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2430 @bind = ('nwiger', 'completed', 'pending%');
2433 To get an OR instead, you can combine it with the arrayref idea:
2437 priority => [ { '=', 2 }, { '>', 5 } ]
2440 Which would generate:
2442 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2443 @bind = ('2', '5', 'nwiger');
2445 If you want to include literal SQL (with or without bind values), just use a
2446 scalar reference or reference to an arrayref as the value:
2449 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2450 date_expires => { '<' => \"now()" }
2453 Which would generate:
2455 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2456 @bind = ('11/26/2008');
2459 =head2 Logic and nesting operators
2461 In the example above,
2462 there is a subtle trap if you want to say something like
2463 this (notice the C<AND>):
2465 WHERE priority != ? AND priority != ?
2467 Because, in Perl you I<can't> do this:
2469 priority => { '!=' => 2, '!=' => 1 }
2471 As the second C<!=> key will obliterate the first. The solution
2472 is to use the special C<-modifier> form inside an arrayref:
2474 priority => [ -and => {'!=', 2},
2478 Normally, these would be joined by C<OR>, but the modifier tells it
2479 to use C<AND> instead. (Hint: You can use this in conjunction with the
2480 C<logic> option to C<new()> in order to change the way your queries
2481 work by default.) B<Important:> Note that the C<-modifier> goes
2482 B<INSIDE> the arrayref, as an extra first element. This will
2483 B<NOT> do what you think it might:
2485 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2487 Here is a quick list of equivalencies, since there is some overlap:
2490 status => {'!=', 'completed', 'not like', 'pending%' }
2491 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2494 status => {'=', ['assigned', 'in-progress']}
2495 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2496 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2500 =head2 Special operators: IN, BETWEEN, etc.
2502 You can also use the hashref format to compare a list of fields using the
2503 C<IN> comparison operator, by specifying the list as an arrayref:
2506 status => 'completed',
2507 reportid => { -in => [567, 2335, 2] }
2510 Which would generate:
2512 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2513 @bind = ('completed', '567', '2335', '2');
2515 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2518 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2519 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2520 'sqltrue' (by default: C<1=1>).
2522 In addition to the array you can supply a chunk of literal sql or
2523 literal sql with bind:
2526 customer => { -in => \[
2527 'SELECT cust_id FROM cust WHERE balance > ?',
2530 status => { -in => \'SELECT status_codes FROM states' },
2536 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2537 AND status IN ( SELECT status_codes FROM states )
2541 Finally, if the argument to C<-in> is not a reference, it will be
2542 treated as a single-element array.
2544 Another pair of operators is C<-between> and C<-not_between>,
2545 used with an arrayref of two values:
2549 completion_date => {
2550 -not_between => ['2002-10-01', '2003-02-06']
2556 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2558 Just like with C<-in> all plausible combinations of literal SQL
2562 start0 => { -between => [ 1, 2 ] },
2563 start1 => { -between => \["? AND ?", 1, 2] },
2564 start2 => { -between => \"lower(x) AND upper(y)" },
2565 start3 => { -between => [
2567 \["upper(?)", 'stuff' ],
2574 ( start0 BETWEEN ? AND ? )
2575 AND ( start1 BETWEEN ? AND ? )
2576 AND ( start2 BETWEEN lower(x) AND upper(y) )
2577 AND ( start3 BETWEEN lower(x) AND upper(?) )
2579 @bind = (1, 2, 1, 2, 'stuff');
2582 These are the two builtin "special operators"; but the
2583 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2585 =head2 Unary operators: bool
2587 If you wish to test against boolean columns or functions within your
2588 database you can use the C<-bool> and C<-not_bool> operators. For
2589 example to test the column C<is_user> being true and the column
2590 C<is_enabled> being false you would use:-
2594 -not_bool => 'is_enabled',
2599 WHERE is_user AND NOT is_enabled
2601 If a more complex combination is required, testing more conditions,
2602 then you should use the and/or operators:-
2607 -not_bool => { two=> { -rlike => 'bar' } },
2608 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2619 (NOT ( three = ? OR three > ? ))
2622 =head2 Nested conditions, -and/-or prefixes
2624 So far, we've seen how multiple conditions are joined with a top-level
2625 C<AND>. We can change this by putting the different conditions we want in
2626 hashes and then putting those hashes in an array. For example:
2631 status => { -like => ['pending%', 'dispatched'] },
2635 status => 'unassigned',
2639 This data structure would create the following:
2641 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2642 OR ( user = ? AND status = ? ) )";
2643 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2646 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2647 to change the logic inside:
2653 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2654 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2661 $stmt = "WHERE ( user = ?
2662 AND ( ( workhrs > ? AND geo = ? )
2663 OR ( workhrs < ? OR geo = ? ) ) )";
2664 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2666 =head3 Algebraic inconsistency, for historical reasons
2668 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2669 operator goes C<outside> of the nested structure; whereas when connecting
2670 several constraints on one column, the C<-and> operator goes
2671 C<inside> the arrayref. Here is an example combining both features:
2674 -and => [a => 1, b => 2],
2675 -or => [c => 3, d => 4],
2676 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2681 WHERE ( ( ( a = ? AND b = ? )
2682 OR ( c = ? OR d = ? )
2683 OR ( e LIKE ? AND e LIKE ? ) ) )
2685 This difference in syntax is unfortunate but must be preserved for
2686 historical reasons. So be careful: the two examples below would
2687 seem algebraically equivalent, but they are not
2690 { -like => 'foo%' },
2691 { -like => '%bar' },
2693 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2696 { col => { -like => 'foo%' } },
2697 { col => { -like => '%bar' } },
2699 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2702 =head2 Literal SQL and value type operators
2704 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2705 side" is a column name and the "right side" is a value (normally rendered as
2706 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2707 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2708 alter this behavior. There are several ways of doing so.
2712 This is a virtual operator that signals the string to its right side is an
2713 identifier (a column name) and not a value. For example to compare two
2714 columns you would write:
2717 priority => { '<', 2 },
2718 requestor => { -ident => 'submitter' },
2723 $stmt = "WHERE priority < ? AND requestor = submitter";
2726 If you are maintaining legacy code you may see a different construct as
2727 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2732 This is a virtual operator that signals that the construct to its right side
2733 is a value to be passed to DBI. This is for example necessary when you want
2734 to write a where clause against an array (for RDBMS that support such
2735 datatypes). For example:
2738 array => { -value => [1, 2, 3] }
2743 $stmt = 'WHERE array = ?';
2744 @bind = ([1, 2, 3]);
2746 Note that if you were to simply say:
2752 the result would probably not be what you wanted:
2754 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2759 Finally, sometimes only literal SQL will do. To include a random snippet
2760 of SQL verbatim, you specify it as a scalar reference. Consider this only
2761 as a last resort. Usually there is a better way. For example:
2764 priority => { '<', 2 },
2765 requestor => { -in => \'(SELECT name FROM hitmen)' },
2770 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2773 Note that in this example, you only get one bind parameter back, since
2774 the verbatim SQL is passed as part of the statement.
2778 Never use untrusted input as a literal SQL argument - this is a massive
2779 security risk (there is no way to check literal snippets for SQL
2780 injections and other nastyness). If you need to deal with untrusted input
2781 use literal SQL with placeholders as described next.
2783 =head3 Literal SQL with placeholders and bind values (subqueries)
2785 If the literal SQL to be inserted has placeholders and bind values,
2786 use a reference to an arrayref (yes this is a double reference --
2787 not so common, but perfectly legal Perl). For example, to find a date
2788 in Postgres you can use something like this:
2791 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2796 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2799 Note that you must pass the bind values in the same format as they are returned
2800 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2801 to C<columns>, you must provide the bind values in the
2802 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2803 scalar value; most commonly the column name, but you can use any scalar value
2804 (including references and blessed references), L<SQL::Abstract> will simply
2805 pass it through intact. So if C<bindtype> is set to C<columns> the above
2806 example will look like:
2809 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2812 Literal SQL is especially useful for nesting parenthesized clauses in the
2813 main SQL query. Here is a first example:
2815 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2819 bar => \["IN ($sub_stmt)" => @sub_bind],
2824 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2825 WHERE c2 < ? AND c3 LIKE ?))";
2826 @bind = (1234, 100, "foo%");
2828 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2829 are expressed in the same way. Of course the C<$sub_stmt> and
2830 its associated bind values can be generated through a former call
2833 my ($sub_stmt, @sub_bind)
2834 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2835 c3 => {-like => "foo%"}});
2838 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2841 In the examples above, the subquery was used as an operator on a column;
2842 but the same principle also applies for a clause within the main C<%where>
2843 hash, like an EXISTS subquery:
2845 my ($sub_stmt, @sub_bind)
2846 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2847 my %where = ( -and => [
2849 \["EXISTS ($sub_stmt)" => @sub_bind],
2854 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2855 WHERE c1 = ? AND c2 > t0.c0))";
2859 Observe that the condition on C<c2> in the subquery refers to
2860 column C<t0.c0> of the main query: this is I<not> a bind
2861 value, so we have to express it through a scalar ref.
2862 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2863 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2864 what we wanted here.
2866 Finally, here is an example where a subquery is used
2867 for expressing unary negation:
2869 my ($sub_stmt, @sub_bind)
2870 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2871 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2873 lname => {like => '%son%'},
2874 \["NOT ($sub_stmt)" => @sub_bind],
2879 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2880 @bind = ('%son%', 10, 20)
2882 =head3 Deprecated usage of Literal SQL
2884 Below are some examples of archaic use of literal SQL. It is shown only as
2885 reference for those who deal with legacy code. Each example has a much
2886 better, cleaner and safer alternative that users should opt for in new code.
2892 my %where = ( requestor => \'IS NOT NULL' )
2894 $stmt = "WHERE requestor IS NOT NULL"
2896 This used to be the way of generating NULL comparisons, before the handling
2897 of C<undef> got formalized. For new code please use the superior syntax as
2898 described in L</Tests for NULL values>.
2902 my %where = ( requestor => \'= submitter' )
2904 $stmt = "WHERE requestor = submitter"
2906 This used to be the only way to compare columns. Use the superior L</-ident>
2907 method for all new code. For example an identifier declared in such a way
2908 will be properly quoted if L</quote_char> is properly set, while the legacy
2909 form will remain as supplied.
2913 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2915 $stmt = "WHERE completed > ? AND is_ready"
2916 @bind = ('2012-12-21')
2918 Using an empty string literal used to be the only way to express a boolean.
2919 For all new code please use the much more readable
2920 L<-bool|/Unary operators: bool> operator.
2926 These pages could go on for a while, since the nesting of the data
2927 structures this module can handle are pretty much unlimited (the
2928 module implements the C<WHERE> expansion as a recursive function
2929 internally). Your best bet is to "play around" with the module a
2930 little to see how the data structures behave, and choose the best
2931 format for your data based on that.
2933 And of course, all the values above will probably be replaced with
2934 variables gotten from forms or the command line. After all, if you
2935 knew everything ahead of time, you wouldn't have to worry about
2936 dynamically-generating SQL and could just hardwire it into your
2939 =head1 ORDER BY CLAUSES
2941 Some functions take an order by clause. This can either be a scalar (just a
2942 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2943 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2946 Given | Will Generate
2947 ---------------------------------------------------------------
2949 'colA' | ORDER BY colA
2951 [qw/colA colB/] | ORDER BY colA, colB
2953 {-asc => 'colA'} | ORDER BY colA ASC
2955 {-desc => 'colB'} | ORDER BY colB DESC
2957 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2959 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2961 \'colA DESC' | ORDER BY colA DESC
2963 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2964 | /* ...with $x bound to ? */
2967 { -asc => 'colA' }, | colA ASC,
2968 { -desc => [qw/colB/] }, | colB DESC,
2969 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2970 \'colE DESC', | colE DESC,
2971 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2972 ] | /* ...with $x bound to ? */
2973 ===============================================================
2977 =head1 SPECIAL OPERATORS
2979 my $sqlmaker = SQL::Abstract->new(special_ops => [
2983 my ($self, $field, $op, $arg) = @_;
2989 handler => 'method_name',
2993 A "special operator" is a SQL syntactic clause that can be
2994 applied to a field, instead of a usual binary operator.
2997 WHERE field IN (?, ?, ?)
2998 WHERE field BETWEEN ? AND ?
2999 WHERE MATCH(field) AGAINST (?, ?)
3001 Special operators IN and BETWEEN are fairly standard and therefore
3002 are builtin within C<SQL::Abstract> (as the overridable methods
3003 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
3004 like the MATCH .. AGAINST example above which is specific to MySQL,
3005 you can write your own operator handlers - supply a C<special_ops>
3006 argument to the C<new> method. That argument takes an arrayref of
3007 operator definitions; each operator definition is a hashref with two
3014 the regular expression to match the operator
3018 Either a coderef or a plain scalar method name. In both cases
3019 the expected return is C<< ($sql, @bind) >>.
3021 When supplied with a method name, it is simply called on the
3022 L<SQL::Abstract> object as:
3024 $self->$method_name($field, $op, $arg)
3028 $field is the LHS of the operator
3029 $op is the part that matched the handler regex
3032 When supplied with a coderef, it is called as:
3034 $coderef->($self, $field, $op, $arg)
3039 For example, here is an implementation
3040 of the MATCH .. AGAINST syntax for MySQL
3042 my $sqlmaker = SQL::Abstract->new(special_ops => [
3044 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
3045 {regex => qr/^match$/i,
3047 my ($self, $field, $op, $arg) = @_;
3048 $arg = [$arg] if not ref $arg;
3049 my $label = $self->_quote($field);
3050 my ($placeholder) = $self->_convert('?');
3051 my $placeholders = join ", ", (($placeholder) x @$arg);
3052 my $sql = $self->_sqlcase('match') . " ($label) "
3053 . $self->_sqlcase('against') . " ($placeholders) ";
3054 my @bind = $self->_bindtype($field, @$arg);
3055 return ($sql, @bind);
3062 =head1 UNARY OPERATORS
3064 my $sqlmaker = SQL::Abstract->new(unary_ops => [
3068 my ($self, $op, $arg) = @_;
3074 handler => 'method_name',
3078 A "unary operator" is a SQL syntactic clause that can be
3079 applied to a field - the operator goes before the field
3081 You can write your own operator handlers - supply a C<unary_ops>
3082 argument to the C<new> method. That argument takes an arrayref of
3083 operator definitions; each operator definition is a hashref with two
3090 the regular expression to match the operator
3094 Either a coderef or a plain scalar method name. In both cases
3095 the expected return is C<< $sql >>.
3097 When supplied with a method name, it is simply called on the
3098 L<SQL::Abstract> object as:
3100 $self->$method_name($op, $arg)
3104 $op is the part that matched the handler regex
3105 $arg is the RHS or argument of the operator
3107 When supplied with a coderef, it is called as:
3109 $coderef->($self, $op, $arg)
3117 Thanks to some benchmarking by Mark Stosberg, it turns out that
3118 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
3119 I must admit this wasn't an intentional design issue, but it's a
3120 byproduct of the fact that you get to control your C<DBI> handles
3123 To maximize performance, use a code snippet like the following:
3125 # prepare a statement handle using the first row
3126 # and then reuse it for the rest of the rows
3128 for my $href (@array_of_hashrefs) {
3129 $stmt ||= $sql->insert('table', $href);
3130 $sth ||= $dbh->prepare($stmt);
3131 $sth->execute($sql->values($href));
3134 The reason this works is because the keys in your C<$href> are sorted
3135 internally by B<SQL::Abstract>. Thus, as long as your data retains
3136 the same structure, you only have to generate the SQL the first time
3137 around. On subsequent queries, simply use the C<values> function provided
3138 by this module to return your values in the correct order.
3140 However this depends on the values having the same type - if, for
3141 example, the values of a where clause may either have values
3142 (resulting in sql of the form C<column = ?> with a single bind
3143 value), or alternatively the values might be C<undef> (resulting in
3144 sql of the form C<column IS NULL> with no bind value) then the
3145 caching technique suggested will not work.
3149 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3150 really like this part (I do, at least). Building up a complex query
3151 can be as simple as the following:
3158 use CGI::FormBuilder;
3161 my $form = CGI::FormBuilder->new(...);
3162 my $sql = SQL::Abstract->new;
3164 if ($form->submitted) {
3165 my $field = $form->field;
3166 my $id = delete $field->{id};
3167 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3170 Of course, you would still have to connect using C<DBI> to run the
3171 query, but the point is that if you make your form look like your
3172 table, the actual query script can be extremely simplistic.
3174 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3175 a fast interface to returning and formatting data. I frequently
3176 use these three modules together to write complex database query
3177 apps in under 50 lines.
3179 =head1 HOW TO CONTRIBUTE
3181 Contributions are always welcome, in all usable forms (we especially
3182 welcome documentation improvements). The delivery methods include git-
3183 or unified-diff formatted patches, GitHub pull requests, or plain bug
3184 reports either via RT or the Mailing list. Contributors are generally
3185 granted full access to the official repository after their first several
3186 patches pass successful review.
3188 This project is maintained in a git repository. The code and related tools are
3189 accessible at the following locations:
3193 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3195 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3197 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3199 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3205 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3206 Great care has been taken to preserve the I<published> behavior
3207 documented in previous versions in the 1.* family; however,
3208 some features that were previously undocumented, or behaved
3209 differently from the documentation, had to be changed in order
3210 to clarify the semantics. Hence, client code that was relying
3211 on some dark areas of C<SQL::Abstract> v1.*
3212 B<might behave differently> in v1.50.
3214 The main changes are:
3220 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3224 support for the { operator => \"..." } construct (to embed literal SQL)
3228 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3232 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3236 defensive programming: check arguments
3240 fixed bug with global logic, which was previously implemented
3241 through global variables yielding side-effects. Prior versions would
3242 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3243 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3244 Now this is interpreted
3245 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3250 fixed semantics of _bindtype on array args
3254 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3255 we just avoid shifting arrays within that tree.
3259 dropped the C<_modlogic> function
3263 =head1 ACKNOWLEDGEMENTS
3265 There are a number of individuals that have really helped out with
3266 this module. Unfortunately, most of them submitted bugs via CPAN
3267 so I have no idea who they are! But the people I do know are:
3269 Ash Berlin (order_by hash term support)
3270 Matt Trout (DBIx::Class support)
3271 Mark Stosberg (benchmarking)
3272 Chas Owens (initial "IN" operator support)
3273 Philip Collins (per-field SQL functions)
3274 Eric Kolve (hashref "AND" support)
3275 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3276 Dan Kubb (support for "quote_char" and "name_sep")
3277 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3278 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3279 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3280 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3281 Oliver Charles (support for "RETURNING" after "INSERT")
3287 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3291 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3293 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3295 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3296 While not an official support venue, C<DBIx::Class> makes heavy use of
3297 C<SQL::Abstract>, and as such list members there are very familiar with
3298 how to create queries.
3302 This module is free software; you may copy this under the same
3303 terms as perl itself (either the GNU General Public License or
3304 the Artistic License)