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 = '1.82';
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) : $sql;
230 # Used by DBIx::Class::SQLMaker->insert
231 sub _insert_returning { shift->_returning(@_) }
234 my ($self, $options) = @_;
236 my $f = $options->{returning};
238 my $fieldlist = $self->_SWITCH_refkind($f, {
239 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
240 SCALAR => sub {$self->_quote($f)},
241 SCALARREF => sub {$$f},
243 return $self->_sqlcase(' returning ') . $fieldlist;
246 sub _insert_HASHREF { # explicit list of fields and then values
247 my ($self, $data) = @_;
249 my @fields = sort keys %$data;
251 my ($sql, @bind) = $self->_insert_values($data);
254 $_ = $self->_quote($_) foreach @fields;
255 $sql = "( ".join(", ", @fields).") ".$sql;
257 return ($sql, @bind);
260 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
261 my ($self, $data) = @_;
263 # no names (arrayref) so can't generate bindtype
264 $self->{bindtype} ne 'columns'
265 or belch "can't do 'columns' bindtype when called with arrayref";
267 my (@values, @all_bind);
268 foreach my $value (@$data) {
269 my ($values, @bind) = $self->_insert_value(undef, $value);
270 push @values, $values;
271 push @all_bind, @bind;
273 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
274 return ($sql, @all_bind);
277 sub _insert_ARRAYREFREF { # literal SQL with bind
278 my ($self, $data) = @_;
280 my ($sql, @bind) = @${$data};
281 $self->_assert_bindval_matches_bindtype(@bind);
283 return ($sql, @bind);
287 sub _insert_SCALARREF { # literal SQL without bind
288 my ($self, $data) = @_;
294 my ($self, $data) = @_;
296 my (@values, @all_bind);
297 foreach my $column (sort keys %$data) {
298 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
299 push @values, $values;
300 push @all_bind, @bind;
302 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
303 return ($sql, @all_bind);
307 my ($self, $column, $v) = @_;
309 my (@values, @all_bind);
310 $self->_SWITCH_refkind($v, {
313 if ($self->{array_datatypes}) { # if array datatype are activated
315 push @all_bind, $self->_bindtype($column, $v);
317 else { # else literal SQL with bind
318 my ($sql, @bind) = @$v;
319 $self->_assert_bindval_matches_bindtype(@bind);
321 push @all_bind, @bind;
325 ARRAYREFREF => sub { # literal SQL with bind
326 my ($sql, @bind) = @${$v};
327 $self->_assert_bindval_matches_bindtype(@bind);
329 push @all_bind, @bind;
332 # THINK : anything useful to do with a HASHREF ?
333 HASHREF => sub { # (nothing, but old SQLA passed it through)
334 #TODO in SQLA >= 2.0 it will die instead
335 belch "HASH ref as bind value in insert is not supported";
337 push @all_bind, $self->_bindtype($column, $v);
340 SCALARREF => sub { # literal SQL without bind
344 SCALAR_or_UNDEF => sub {
346 push @all_bind, $self->_bindtype($column, $v);
351 my $sql = join(", ", @values);
352 return ($sql, @all_bind);
357 #======================================================================
359 #======================================================================
364 my $table = $self->_table(shift);
365 my $data = shift || return;
369 # first build the 'SET' part of the sql statement
370 my (@set, @all_bind);
371 puke "Unsupported data type specified to \$sql->update"
372 unless ref $data eq 'HASH';
374 for my $k (sort keys %$data) {
377 my $label = $self->_quote($k);
379 $self->_SWITCH_refkind($v, {
381 if ($self->{array_datatypes}) { # array datatype
382 push @set, "$label = ?";
383 push @all_bind, $self->_bindtype($k, $v);
385 else { # literal SQL with bind
386 my ($sql, @bind) = @$v;
387 $self->_assert_bindval_matches_bindtype(@bind);
388 push @set, "$label = $sql";
389 push @all_bind, @bind;
392 ARRAYREFREF => sub { # literal SQL with bind
393 my ($sql, @bind) = @${$v};
394 $self->_assert_bindval_matches_bindtype(@bind);
395 push @set, "$label = $sql";
396 push @all_bind, @bind;
398 SCALARREF => sub { # literal SQL without bind
399 push @set, "$label = $$v";
402 my ($op, $arg, @rest) = %$v;
404 puke 'Operator calls in update must be in the form { -op => $arg }'
405 if (@rest or not $op =~ /^\-(.+)/);
407 local $self->{_nested_func_lhs} = $k;
408 my ($sql, @bind) = $self->_where_unary_op ($1, $arg);
410 push @set, "$label = $sql";
411 push @all_bind, @bind;
413 SCALAR_or_UNDEF => sub {
414 push @set, "$label = ?";
415 push @all_bind, $self->_bindtype($k, $v);
421 my $sql = $self->_sqlcase('update') . " $table " . $self->_sqlcase('set ')
425 my($where_sql, @where_bind) = $self->where($where);
427 push @all_bind, @where_bind;
430 if ($options->{returning}) {
431 my ($returning_sql, @returning_bind) = $self->_update_returning ($options);
432 $sql .= $returning_sql;
433 push @all_bind, @returning_bind;
436 return wantarray ? ($sql, @all_bind) : $sql;
439 sub _update_returning { shift->_returning(@_) }
443 #======================================================================
445 #======================================================================
450 my $table = $self->_table(shift);
451 my $fields = shift || '*';
455 my($where_sql, @bind) = $self->where($where, $order);
457 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
459 my $sql = join(' ', $self->_sqlcase('select'), $f,
460 $self->_sqlcase('from'), $table)
463 return wantarray ? ($sql, @bind) : $sql;
466 #======================================================================
468 #======================================================================
473 my $table = $self->_table(shift);
477 my($where_sql, @bind) = $self->where($where);
478 my $sql = $self->_sqlcase('delete from') . " $table" . $where_sql;
480 if ($options->{returning}) {
481 my ($returning_sql, @returning_bind) = $self->_delete_returning ($options);
482 $sql .= $returning_sql;
483 push @bind, @returning_bind;
486 return wantarray ? ($sql, @bind) : $sql;
489 sub _delete_returning { shift->_returning(@_) }
493 #======================================================================
495 #======================================================================
499 # Finally, a separate routine just to handle WHERE clauses
501 my ($self, $where, $order) = @_;
504 my ($sql, @bind) = $self->_recurse_where($where);
505 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
509 my ($order_sql, @order_bind) = $self->_order_by($order);
511 push @bind, @order_bind;
514 return wantarray ? ($sql, @bind) : $sql;
519 my ($self, $where, $logic) = @_;
521 # dispatch on appropriate method according to refkind of $where
522 my $method = $self->_METHOD_FOR_refkind("_where", $where);
524 my ($sql, @bind) = $self->$method($where, $logic);
526 # DBIx::Class used to call _recurse_where in scalar context
527 # something else might too...
529 return ($sql, @bind);
532 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
539 #======================================================================
540 # WHERE: top-level ARRAYREF
541 #======================================================================
544 sub _where_ARRAYREF {
545 my ($self, $where, $logic) = @_;
547 $logic = uc($logic || $self->{logic});
548 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
550 my @clauses = @$where;
552 my (@sql_clauses, @all_bind);
553 # need to use while() so can shift() for pairs
555 my $el = shift @clauses;
557 $el = undef if (defined $el and ! length $el);
559 # switch according to kind of $el and get corresponding ($sql, @bind)
560 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
562 # skip empty elements, otherwise get invalid trailing AND stuff
563 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
567 $self->_assert_bindval_matches_bindtype(@b);
571 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
573 SCALARREF => sub { ($$el); },
576 # top-level arrayref with scalars, recurse in pairs
577 $self->_recurse_where({$el => shift(@clauses)})
580 UNDEF => sub {puke "Supplying an empty left hand side argument is not supported in array-pairs" },
584 push @sql_clauses, $sql;
585 push @all_bind, @bind;
589 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
592 #======================================================================
593 # WHERE: top-level ARRAYREFREF
594 #======================================================================
596 sub _where_ARRAYREFREF {
597 my ($self, $where) = @_;
598 my ($sql, @bind) = @$$where;
599 $self->_assert_bindval_matches_bindtype(@bind);
600 return ($sql, @bind);
603 #======================================================================
604 # WHERE: top-level HASHREF
605 #======================================================================
608 my ($self, $where) = @_;
609 my (@sql_clauses, @all_bind);
611 for my $k (sort keys %$where) {
612 my $v = $where->{$k};
614 # ($k => $v) is either a special unary op or a regular hashpair
615 my ($sql, @bind) = do {
617 # put the operator in canonical form
619 $op = substr $op, 1; # remove initial dash
620 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
621 $op =~ s/\s+/ /g; # compress whitespace
623 # so that -not_foo works correctly
624 $op =~ s/^not_/NOT /i;
626 $self->_debug("Unary OP(-$op) within hashref, recursing...");
627 my ($s, @b) = $self->_where_unary_op ($op, $v);
629 # top level vs nested
630 # we assume that handled unary ops will take care of their ()s
632 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
634 ( defined $self->{_nested_func_lhs} and $self->{_nested_func_lhs} eq $k )
640 if (is_literal_value ($v) ) {
641 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
644 puke "Supplying an empty left hand side argument is not supported in hash-pairs";
648 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
649 $self->$method($k, $v);
653 push @sql_clauses, $sql;
654 push @all_bind, @bind;
657 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
660 sub _where_unary_op {
661 my ($self, $op, $rhs) = @_;
663 # top level special ops are illegal in general
664 # this includes the -ident/-value ops (dual purpose unary and special)
665 puke "Illegal use of top-level '-$op'"
666 if ! defined $self->{_nested_func_lhs} and List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}};
668 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
669 my $handler = $op_entry->{handler};
671 if (not ref $handler) {
672 if ($op =~ s/ [_\s]? \d+ $//x ) {
673 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
674 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
676 return $self->$handler ($op, $rhs);
678 elsif (ref $handler eq 'CODE') {
679 return $handler->($self, $op, $rhs);
682 puke "Illegal handler for operator $op - expecting a method name or a coderef";
686 $self->_debug("Generic unary OP: $op - recursing as function");
688 $self->_assert_pass_injection_guard($op);
690 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
692 puke "Illegal use of top-level '-$op'"
693 unless defined $self->{_nested_func_lhs};
696 $self->_convert('?'),
697 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
701 $self->_recurse_where ($rhs)
705 $sql = sprintf ('%s %s',
706 $self->_sqlcase($op),
710 return ($sql, @bind);
713 sub _where_op_ANDOR {
714 my ($self, $op, $v) = @_;
716 $self->_SWITCH_refkind($v, {
718 return $self->_where_ARRAYREF($v, $op);
722 return ( $op =~ /^or/i )
723 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
724 : $self->_where_HASHREF($v);
728 puke "-$op => \\\$scalar makes little sense, use " .
730 ? '[ \$scalar, \%rest_of_conditions ] instead'
731 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
736 puke "-$op => \\[...] makes little sense, use " .
738 ? '[ \[...], \%rest_of_conditions ] instead'
739 : '-and => [ \[...], \%rest_of_conditions ] instead'
743 SCALAR => sub { # permissively interpreted as SQL
744 puke "-$op => \$value makes little sense, use -bool => \$value instead";
748 puke "-$op => undef not supported";
754 my ($self, $op, $v) = @_;
756 $self->_SWITCH_refkind($v, {
758 SCALAR => sub { # permissively interpreted as SQL
759 belch "literal SQL should be -nest => \\'scalar' "
760 . "instead of -nest => 'scalar' ";
765 puke "-$op => undef not supported";
769 $self->_recurse_where ($v);
777 my ($self, $op, $v) = @_;
779 my ($s, @b) = $self->_SWITCH_refkind($v, {
780 SCALAR => sub { # interpreted as SQL column
781 $self->_convert($self->_quote($v));
785 puke "-$op => undef not supported";
789 $self->_recurse_where ($v);
793 $s = "(NOT $s)" if $op =~ /^not/i;
798 sub _where_op_IDENT {
800 my ($op, $rhs) = splice @_, -2;
801 if (! defined $rhs or length ref $rhs) {
802 puke "-$op requires a single plain scalar argument (a quotable identifier)";
805 # in case we are called as a top level special op (no '=')
808 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
816 sub _where_op_VALUE {
818 my ($op, $rhs) = splice @_, -2;
820 # in case we are called as a top level special op (no '=')
824 if (! defined $rhs) {
826 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
833 ( defined $lhs ? $lhs : $self->{_nested_func_lhs} ),
840 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
844 $self->_convert('?'),
850 sub _where_hashpair_ARRAYREF {
851 my ($self, $k, $v) = @_;
854 my @v = @$v; # need copy because of shift below
855 $self->_debug("ARRAY($k) means distribute over elements");
857 # put apart first element if it is an operator (-and, -or)
859 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
863 my @distributed = map { {$k => $_} } @v;
866 $self->_debug("OP($op) reinjected into the distributed array");
867 unshift @distributed, $op;
870 my $logic = $op ? substr($op, 1) : '';
872 return $self->_recurse_where(\@distributed, $logic);
875 $self->_debug("empty ARRAY($k) means 0=1");
876 return ($self->{sqlfalse});
880 sub _where_hashpair_HASHREF {
881 my ($self, $k, $v, $logic) = @_;
884 local $self->{_nested_func_lhs} = defined $self->{_nested_func_lhs}
885 ? $self->{_nested_func_lhs}
889 my ($all_sql, @all_bind);
891 for my $orig_op (sort keys %$v) {
892 my $val = $v->{$orig_op};
894 # put the operator in canonical form
897 # FIXME - we need to phase out dash-less ops
898 $op =~ s/^-//; # remove possible initial dash
899 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
900 $op =~ s/\s+/ /g; # compress whitespace
902 $self->_assert_pass_injection_guard($op);
905 $op =~ s/^is_not/IS NOT/i;
907 # so that -not_foo works correctly
908 $op =~ s/^not_/NOT /i;
910 # another retarded special case: foo => { $op => { -value => undef } }
911 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
917 # CASE: col-value logic modifiers
918 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
919 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
921 # CASE: special operators like -in or -between
922 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
923 my $handler = $special_op->{handler};
925 puke "No handler supplied for special operator $orig_op";
927 elsif (not ref $handler) {
928 ($sql, @bind) = $self->$handler ($k, $op, $val);
930 elsif (ref $handler eq 'CODE') {
931 ($sql, @bind) = $handler->($self, $k, $op, $val);
934 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
938 $self->_SWITCH_refkind($val, {
940 ARRAYREF => sub { # CASE: col => {op => \@vals}
941 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
944 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
945 my ($sub_sql, @sub_bind) = @$$val;
946 $self->_assert_bindval_matches_bindtype(@sub_bind);
947 $sql = join ' ', $self->_convert($self->_quote($k)),
948 $self->_sqlcase($op),
953 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
955 $op =~ /^not$/i ? 'is not' # legacy
956 : $op =~ $self->{equality_op} ? 'is'
957 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
958 : $op =~ $self->{inequality_op} ? 'is not'
959 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
960 : puke "unexpected operator '$orig_op' with undef operand";
962 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
965 FALLBACK => sub { # CASE: col => {op/func => $stuff}
966 ($sql, @bind) = $self->_where_unary_op ($op, $val);
969 $self->_convert($self->_quote($k)),
970 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
976 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
977 push @all_bind, @bind;
979 return ($all_sql, @all_bind);
982 sub _where_field_IS {
983 my ($self, $k, $op, $v) = @_;
985 my ($s) = $self->_SWITCH_refkind($v, {
988 $self->_convert($self->_quote($k)),
989 map { $self->_sqlcase($_)} ($op, 'null')
992 puke "$op can only take undef as argument";
999 sub _where_field_op_ARRAYREF {
1000 my ($self, $k, $op, $vals) = @_;
1002 my @vals = @$vals; #always work on a copy
1005 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
1007 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
1010 # see if the first element is an -and/-or op
1012 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
1017 # a long standing API wart - an attempt to change this behavior during
1018 # the 1.50 series failed *spectacularly*. Warn instead and leave the
1023 (!$logic or $logic eq 'OR')
1025 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
1028 belch "A multi-element arrayref as an argument to the inequality op '$o' "
1029 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
1030 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
1034 # distribute $op over each remaining member of @vals, append logic if exists
1035 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
1039 # try to DWIM on equality operators
1041 $op =~ $self->{equality_op} ? $self->{sqlfalse}
1042 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
1043 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
1044 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
1045 : puke "operator '$op' applied on an empty array (field '$k')";
1050 sub _where_hashpair_SCALARREF {
1051 my ($self, $k, $v) = @_;
1052 $self->_debug("SCALAR($k) means literal SQL: $$v");
1053 my $sql = $self->_quote($k) . " " . $$v;
1057 # literal SQL with bind
1058 sub _where_hashpair_ARRAYREFREF {
1059 my ($self, $k, $v) = @_;
1060 $self->_debug("REF($k) means literal SQL: @${$v}");
1061 my ($sql, @bind) = @$$v;
1062 $self->_assert_bindval_matches_bindtype(@bind);
1063 $sql = $self->_quote($k) . " " . $sql;
1064 return ($sql, @bind );
1067 # literal SQL without bind
1068 sub _where_hashpair_SCALAR {
1069 my ($self, $k, $v) = @_;
1070 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
1071 my $sql = join ' ', $self->_convert($self->_quote($k)),
1072 $self->_sqlcase($self->{cmp}),
1073 $self->_convert('?');
1074 my @bind = $self->_bindtype($k, $v);
1075 return ( $sql, @bind);
1079 sub _where_hashpair_UNDEF {
1080 my ($self, $k, $v) = @_;
1081 $self->_debug("UNDEF($k) means IS NULL");
1082 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
1086 #======================================================================
1087 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
1088 #======================================================================
1091 sub _where_SCALARREF {
1092 my ($self, $where) = @_;
1095 $self->_debug("SCALAR(*top) means literal SQL: $$where");
1101 my ($self, $where) = @_;
1104 $self->_debug("NOREF(*top) means literal SQL: $where");
1115 #======================================================================
1116 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
1117 #======================================================================
1120 sub _where_field_BETWEEN {
1121 my ($self, $k, $op, $vals) = @_;
1123 my ($label, $and, $placeholder);
1124 $label = $self->_convert($self->_quote($k));
1125 $and = ' ' . $self->_sqlcase('and') . ' ';
1126 $placeholder = $self->_convert('?');
1127 $op = $self->_sqlcase($op);
1129 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1131 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1132 ARRAYREFREF => sub {
1133 my ($s, @b) = @$$vals;
1134 $self->_assert_bindval_matches_bindtype(@b);
1141 puke $invalid_args if @$vals != 2;
1143 my (@all_sql, @all_bind);
1144 foreach my $val (@$vals) {
1145 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1147 return ($placeholder, $self->_bindtype($k, $val) );
1152 ARRAYREFREF => sub {
1153 my ($sql, @bind) = @$$val;
1154 $self->_assert_bindval_matches_bindtype(@bind);
1155 return ($sql, @bind);
1158 my ($func, $arg, @rest) = %$val;
1159 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1160 if (@rest or $func !~ /^ \- (.+)/x);
1161 $self->_where_unary_op ($1 => $arg);
1167 push @all_sql, $sql;
1168 push @all_bind, @bind;
1172 (join $and, @all_sql),
1181 my $sql = "( $label $op $clause )";
1182 return ($sql, @bind)
1186 sub _where_field_IN {
1187 my ($self, $k, $op, $vals) = @_;
1189 # backwards compatibility : if scalar, force into an arrayref
1190 $vals = [$vals] if defined $vals && ! ref $vals;
1192 my ($label) = $self->_convert($self->_quote($k));
1193 my ($placeholder) = $self->_convert('?');
1194 $op = $self->_sqlcase($op);
1196 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1197 ARRAYREF => sub { # list of choices
1198 if (@$vals) { # nonempty list
1199 my (@all_sql, @all_bind);
1201 for my $val (@$vals) {
1202 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1204 return ($placeholder, $val);
1209 ARRAYREFREF => sub {
1210 my ($sql, @bind) = @$$val;
1211 $self->_assert_bindval_matches_bindtype(@bind);
1212 return ($sql, @bind);
1215 my ($func, $arg, @rest) = %$val;
1216 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1217 if (@rest or $func !~ /^ \- (.+)/x);
1218 $self->_where_unary_op ($1 => $arg);
1222 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1223 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1224 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1225 . 'will emit the logically correct SQL instead of raising this exception)'
1229 push @all_sql, $sql;
1230 push @all_bind, @bind;
1234 sprintf ('%s %s ( %s )',
1237 join (', ', @all_sql)
1239 $self->_bindtype($k, @all_bind),
1242 else { # empty list : some databases won't understand "IN ()", so DWIM
1243 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1248 SCALARREF => sub { # literal SQL
1249 my $sql = $self->_open_outer_paren ($$vals);
1250 return ("$label $op ( $sql )");
1252 ARRAYREFREF => sub { # literal SQL with bind
1253 my ($sql, @bind) = @$$vals;
1254 $self->_assert_bindval_matches_bindtype(@bind);
1255 $sql = $self->_open_outer_paren ($sql);
1256 return ("$label $op ( $sql )", @bind);
1260 puke "Argument passed to the '$op' operator can not be undefined";
1264 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1268 return ($sql, @bind);
1271 # Some databases (SQLite) treat col IN (1, 2) different from
1272 # col IN ( (1, 2) ). Use this to strip all outer parens while
1273 # adding them back in the corresponding method
1274 sub _open_outer_paren {
1275 my ($self, $sql) = @_;
1277 while ( my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs ) {
1279 # there are closing parens inside, need the heavy duty machinery
1280 # to reevaluate the extraction starting from $sql (full reevaluation)
1281 if ( $inner =~ /\)/ ) {
1282 require Text::Balanced;
1284 my (undef, $remainder) = do {
1285 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1287 Text::Balanced::extract_bracketed( $sql, '()', qr/\s*/ );
1290 # the entire expression needs to be a balanced bracketed thing
1291 # (after an extract no remainder sans trailing space)
1292 last if defined $remainder and $remainder =~ /\S/;
1302 #======================================================================
1304 #======================================================================
1307 my ($self, $arg) = @_;
1310 for my $c ($self->_order_by_chunks ($arg) ) {
1311 $self->_SWITCH_refkind ($c, {
1312 SCALAR => sub { push @sql, $c },
1313 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1319 $self->_sqlcase(' order by'),
1325 return wantarray ? ($sql, @bind) : $sql;
1328 sub _order_by_chunks {
1329 my ($self, $arg) = @_;
1331 return $self->_SWITCH_refkind($arg, {
1334 map { $self->_order_by_chunks ($_ ) } @$arg;
1337 ARRAYREFREF => sub {
1338 my ($s, @b) = @$$arg;
1339 $self->_assert_bindval_matches_bindtype(@b);
1343 SCALAR => sub {$self->_quote($arg)},
1345 UNDEF => sub {return () },
1347 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1350 # get first pair in hash
1351 my ($key, $val, @rest) = %$arg;
1353 return () unless $key;
1355 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1356 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1362 for my $c ($self->_order_by_chunks ($val)) {
1365 $self->_SWITCH_refkind ($c, {
1370 ($sql, @bind) = @$c;
1374 $sql = $sql . ' ' . $self->_sqlcase($direction);
1376 push @ret, [ $sql, @bind];
1385 #======================================================================
1386 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1387 #======================================================================
1392 $self->_SWITCH_refkind($from, {
1393 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1394 SCALAR => sub {$self->_quote($from)},
1395 SCALARREF => sub {$$from},
1400 #======================================================================
1402 #======================================================================
1404 # highly optimized, as it's called way too often
1406 # my ($self, $label) = @_;
1408 return '' unless defined $_[1];
1409 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1411 $_[0]->{quote_char} or
1412 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1414 my $qref = ref $_[0]->{quote_char};
1416 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1417 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1418 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1420 my $esc = $_[0]->{escape_char} || $r;
1422 # parts containing * are naturally unquoted
1423 return join( $_[0]->{name_sep}||'', map
1424 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1425 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1430 # Conversion, if applicable
1432 #my ($self, $arg) = @_;
1433 if ($_[0]->{convert}) {
1434 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1441 #my ($self, $col, @vals) = @_;
1442 # called often - tighten code
1443 return $_[0]->{bindtype} eq 'columns'
1444 ? map {[$_[1], $_]} @_[2 .. $#_]
1449 # Dies if any element of @bind is not in [colname => value] format
1450 # if bindtype is 'columns'.
1451 sub _assert_bindval_matches_bindtype {
1452 # my ($self, @bind) = @_;
1454 if ($self->{bindtype} eq 'columns') {
1456 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1457 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1463 sub _join_sql_clauses {
1464 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1466 if (@$clauses_aref > 1) {
1467 my $join = " " . $self->_sqlcase($logic) . " ";
1468 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1469 return ($sql, @$bind_aref);
1471 elsif (@$clauses_aref) {
1472 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1475 return (); # if no SQL, ignore @$bind_aref
1480 # Fix SQL case, if so requested
1482 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1483 # don't touch the argument ... crooked logic, but let's not change it!
1484 return $_[0]->{case} ? $_[1] : uc($_[1]);
1488 #======================================================================
1489 # DISPATCHING FROM REFKIND
1490 #======================================================================
1493 my ($self, $data) = @_;
1495 return 'UNDEF' unless defined $data;
1497 # blessed objects are treated like scalars
1498 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1500 return 'SCALAR' unless $ref;
1503 while ($ref eq 'REF') {
1505 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1509 return ($ref||'SCALAR') . ('REF' x $n_steps);
1513 my ($self, $data) = @_;
1514 my @try = ($self->_refkind($data));
1515 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1516 push @try, 'FALLBACK';
1520 sub _METHOD_FOR_refkind {
1521 my ($self, $meth_prefix, $data) = @_;
1524 for (@{$self->_try_refkind($data)}) {
1525 $method = $self->can($meth_prefix."_".$_)
1529 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1533 sub _SWITCH_refkind {
1534 my ($self, $data, $dispatch_table) = @_;
1537 for (@{$self->_try_refkind($data)}) {
1538 $coderef = $dispatch_table->{$_}
1542 puke "no dispatch entry for ".$self->_refkind($data)
1551 #======================================================================
1552 # VALUES, GENERATE, AUTOLOAD
1553 #======================================================================
1555 # LDNOTE: original code from nwiger, didn't touch code in that section
1556 # I feel the AUTOLOAD stuff should not be the default, it should
1557 # only be activated on explicit demand by user.
1561 my $data = shift || return;
1562 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1563 unless ref $data eq 'HASH';
1566 foreach my $k ( sort keys %$data ) {
1567 my $v = $data->{$k};
1568 $self->_SWITCH_refkind($v, {
1570 if ($self->{array_datatypes}) { # array datatype
1571 push @all_bind, $self->_bindtype($k, $v);
1573 else { # literal SQL with bind
1574 my ($sql, @bind) = @$v;
1575 $self->_assert_bindval_matches_bindtype(@bind);
1576 push @all_bind, @bind;
1579 ARRAYREFREF => sub { # literal SQL with bind
1580 my ($sql, @bind) = @${$v};
1581 $self->_assert_bindval_matches_bindtype(@bind);
1582 push @all_bind, @bind;
1584 SCALARREF => sub { # literal SQL without bind
1586 SCALAR_or_UNDEF => sub {
1587 push @all_bind, $self->_bindtype($k, $v);
1598 my(@sql, @sqlq, @sqlv);
1602 if ($ref eq 'HASH') {
1603 for my $k (sort keys %$_) {
1606 my $label = $self->_quote($k);
1607 if ($r eq 'ARRAY') {
1608 # literal SQL with bind
1609 my ($sql, @bind) = @$v;
1610 $self->_assert_bindval_matches_bindtype(@bind);
1611 push @sqlq, "$label = $sql";
1613 } elsif ($r eq 'SCALAR') {
1614 # literal SQL without bind
1615 push @sqlq, "$label = $$v";
1617 push @sqlq, "$label = ?";
1618 push @sqlv, $self->_bindtype($k, $v);
1621 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1622 } elsif ($ref eq 'ARRAY') {
1623 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1626 if ($r eq 'ARRAY') { # literal SQL with bind
1627 my ($sql, @bind) = @$v;
1628 $self->_assert_bindval_matches_bindtype(@bind);
1631 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1632 # embedded literal SQL
1639 push @sql, '(' . join(', ', @sqlq) . ')';
1640 } elsif ($ref eq 'SCALAR') {
1644 # strings get case twiddled
1645 push @sql, $self->_sqlcase($_);
1649 my $sql = join ' ', @sql;
1651 # this is pretty tricky
1652 # if ask for an array, return ($stmt, @bind)
1653 # otherwise, s/?/shift @sqlv/ to put it inline
1655 return ($sql, @sqlv);
1657 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1658 ref $d ? $d->[1] : $d/e;
1667 # This allows us to check for a local, then _form, attr
1669 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1670 return $self->generate($name, @_);
1681 SQL::Abstract - Generate SQL from Perl data structures
1687 my $sql = SQL::Abstract->new;
1689 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1691 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1693 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1695 my($stmt, @bind) = $sql->delete($table, \%where);
1697 # Then, use these in your DBI statements
1698 my $sth = $dbh->prepare($stmt);
1699 $sth->execute(@bind);
1701 # Just generate the WHERE clause
1702 my($stmt, @bind) = $sql->where(\%where, $order);
1704 # Return values in the same order, for hashed queries
1705 # See PERFORMANCE section for more details
1706 my @bind = $sql->values(\%fieldvals);
1710 This module was inspired by the excellent L<DBIx::Abstract>.
1711 However, in using that module I found that what I really wanted
1712 to do was generate SQL, but still retain complete control over my
1713 statement handles and use the DBI interface. So, I set out to
1714 create an abstract SQL generation module.
1716 While based on the concepts used by L<DBIx::Abstract>, there are
1717 several important differences, especially when it comes to WHERE
1718 clauses. I have modified the concepts used to make the SQL easier
1719 to generate from Perl data structures and, IMO, more intuitive.
1720 The underlying idea is for this module to do what you mean, based
1721 on the data structures you provide it. The big advantage is that
1722 you don't have to modify your code every time your data changes,
1723 as this module figures it out.
1725 To begin with, an SQL INSERT is as easy as just specifying a hash
1726 of C<key=value> pairs:
1729 name => 'Jimbo Bobson',
1730 phone => '123-456-7890',
1731 address => '42 Sister Lane',
1732 city => 'St. Louis',
1733 state => 'Louisiana',
1736 The SQL can then be generated with this:
1738 my($stmt, @bind) = $sql->insert('people', \%data);
1740 Which would give you something like this:
1742 $stmt = "INSERT INTO people
1743 (address, city, name, phone, state)
1744 VALUES (?, ?, ?, ?, ?)";
1745 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1746 '123-456-7890', 'Louisiana');
1748 These are then used directly in your DBI code:
1750 my $sth = $dbh->prepare($stmt);
1751 $sth->execute(@bind);
1753 =head2 Inserting and Updating Arrays
1755 If your database has array types (like for example Postgres),
1756 activate the special option C<< array_datatypes => 1 >>
1757 when creating the C<SQL::Abstract> object.
1758 Then you may use an arrayref to insert and update database array types:
1760 my $sql = SQL::Abstract->new(array_datatypes => 1);
1762 planets => [qw/Mercury Venus Earth Mars/]
1765 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1769 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1771 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1774 =head2 Inserting and Updating SQL
1776 In order to apply SQL functions to elements of your C<%data> you may
1777 specify a reference to an arrayref for the given hash value. For example,
1778 if you need to execute the Oracle C<to_date> function on a value, you can
1779 say something like this:
1783 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1786 The first value in the array is the actual SQL. Any other values are
1787 optional and would be included in the bind values array. This gives
1790 my($stmt, @bind) = $sql->insert('people', \%data);
1792 $stmt = "INSERT INTO people (name, date_entered)
1793 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1794 @bind = ('Bill', '03/02/2003');
1796 An UPDATE is just as easy, all you change is the name of the function:
1798 my($stmt, @bind) = $sql->update('people', \%data);
1800 Notice that your C<%data> isn't touched; the module will generate
1801 the appropriately quirky SQL for you automatically. Usually you'll
1802 want to specify a WHERE clause for your UPDATE, though, which is
1803 where handling C<%where> hashes comes in handy...
1805 =head2 Complex where statements
1807 This module can generate pretty complicated WHERE statements
1808 easily. For example, simple C<key=value> pairs are taken to mean
1809 equality, and if you want to see if a field is within a set
1810 of values, you can use an arrayref. Let's say we wanted to
1811 SELECT some data based on this criteria:
1814 requestor => 'inna',
1815 worker => ['nwiger', 'rcwe', 'sfz'],
1816 status => { '!=', 'completed' }
1819 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1821 The above would give you something like this:
1823 $stmt = "SELECT * FROM tickets WHERE
1824 ( requestor = ? ) AND ( status != ? )
1825 AND ( worker = ? OR worker = ? OR worker = ? )";
1826 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1828 Which you could then use in DBI code like so:
1830 my $sth = $dbh->prepare($stmt);
1831 $sth->execute(@bind);
1837 The methods are simple. There's one for every major SQL operation,
1838 and a constructor you use first. The arguments are specified in a
1839 similar order for each method (table, then fields, then a where
1840 clause) to try and simplify things.
1842 =head2 new(option => 'value')
1844 The C<new()> function takes a list of options and values, and returns
1845 a new B<SQL::Abstract> object which can then be used to generate SQL
1846 through the methods below. The options accepted are:
1852 If set to 'lower', then SQL will be generated in all lowercase. By
1853 default SQL is generated in "textbook" case meaning something like:
1855 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1857 Any setting other than 'lower' is ignored.
1861 This determines what the default comparison operator is. By default
1862 it is C<=>, meaning that a hash like this:
1864 %where = (name => 'nwiger', email => 'nate@wiger.org');
1866 Will generate SQL like this:
1868 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1870 However, you may want loose comparisons by default, so if you set
1871 C<cmp> to C<like> you would get SQL such as:
1873 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1875 You can also override the comparison on an individual basis - see
1876 the huge section on L</"WHERE CLAUSES"> at the bottom.
1878 =item sqltrue, sqlfalse
1880 Expressions for inserting boolean values within SQL statements.
1881 By default these are C<1=1> and C<1=0>. They are used
1882 by the special operators C<-in> and C<-not_in> for generating
1883 correct SQL even when the argument is an empty array (see below).
1887 This determines the default logical operator for multiple WHERE
1888 statements in arrays or hashes. If absent, the default logic is "or"
1889 for arrays, and "and" for hashes. This means that a WHERE
1893 event_date => {'>=', '2/13/99'},
1894 event_date => {'<=', '4/24/03'},
1897 will generate SQL like this:
1899 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1901 This is probably not what you want given this query, though (look
1902 at the dates). To change the "OR" to an "AND", simply specify:
1904 my $sql = SQL::Abstract->new(logic => 'and');
1906 Which will change the above C<WHERE> to:
1908 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1910 The logic can also be changed locally by inserting
1911 a modifier in front of an arrayref :
1913 @where = (-and => [event_date => {'>=', '2/13/99'},
1914 event_date => {'<=', '4/24/03'} ]);
1916 See the L</"WHERE CLAUSES"> section for explanations.
1920 This will automatically convert comparisons using the specified SQL
1921 function for both column and value. This is mostly used with an argument
1922 of C<upper> or C<lower>, so that the SQL will have the effect of
1923 case-insensitive "searches". For example, this:
1925 $sql = SQL::Abstract->new(convert => 'upper');
1926 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1928 Will turn out the following SQL:
1930 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1932 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1933 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1934 not validate this option; it will just pass through what you specify verbatim).
1938 This is a kludge because many databases suck. For example, you can't
1939 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1940 Instead, you have to use C<bind_param()>:
1942 $sth->bind_param(1, 'reg data');
1943 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1945 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1946 which loses track of which field each slot refers to. Fear not.
1948 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1949 Currently, you can specify either C<normal> (default) or C<columns>. If you
1950 specify C<columns>, you will get an array that looks like this:
1952 my $sql = SQL::Abstract->new(bindtype => 'columns');
1953 my($stmt, @bind) = $sql->insert(...);
1956 [ 'column1', 'value1' ],
1957 [ 'column2', 'value2' ],
1958 [ 'column3', 'value3' ],
1961 You can then iterate through this manually, using DBI's C<bind_param()>.
1963 $sth->prepare($stmt);
1966 my($col, $data) = @$_;
1967 if ($col eq 'details' || $col eq 'comments') {
1968 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1969 } elsif ($col eq 'image') {
1970 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1972 $sth->bind_param($i, $data);
1976 $sth->execute; # execute without @bind now
1978 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1979 Basically, the advantage is still that you don't have to care which fields
1980 are or are not included. You could wrap that above C<for> loop in a simple
1981 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1982 get a layer of abstraction over manual SQL specification.
1984 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1985 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1986 will expect the bind values in this format.
1990 This is the character that a table or column name will be quoted
1991 with. By default this is an empty string, but you could set it to
1992 the character C<`>, to generate SQL like this:
1994 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1996 Alternatively, you can supply an array ref of two items, the first being the left
1997 hand quote character, and the second the right hand quote character. For
1998 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1999 that generates SQL like this:
2001 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
2003 Quoting is useful if you have tables or columns names that are reserved
2004 words in your database's SQL dialect.
2008 This is the character that will be used to escape L</quote_char>s appearing
2009 in an identifier before it has been quoted.
2011 The parameter default in case of a single L</quote_char> character is the quote
2014 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
2015 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
2016 of the B<opening (left)> L</quote_char> within the identifier are currently left
2017 untouched. The default for opening-closing-style quotes may change in future
2018 versions, thus you are B<strongly encouraged> to specify the escape character
2023 This is the character that separates a table and column name. It is
2024 necessary to specify this when the C<quote_char> option is selected,
2025 so that tables and column names can be individually quoted like this:
2027 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
2029 =item injection_guard
2031 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
2032 column name specified in a query structure. This is a safety mechanism to avoid
2033 injection attacks when mishandling user input e.g.:
2035 my %condition_as_column_value_pairs = get_values_from_user();
2036 $sqla->select( ... , \%condition_as_column_value_pairs );
2038 If the expression matches an exception is thrown. Note that literal SQL
2039 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
2041 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
2043 =item array_datatypes
2045 When this option is true, arrayrefs in INSERT or UPDATE are
2046 interpreted as array datatypes and are passed directly
2048 When this option is false, arrayrefs are interpreted
2049 as literal SQL, just like refs to arrayrefs
2050 (but this behavior is for backwards compatibility; when writing
2051 new queries, use the "reference to arrayref" syntax
2057 Takes a reference to a list of "special operators"
2058 to extend the syntax understood by L<SQL::Abstract>.
2059 See section L</"SPECIAL OPERATORS"> for details.
2063 Takes a reference to a list of "unary operators"
2064 to extend the syntax understood by L<SQL::Abstract>.
2065 See section L</"UNARY OPERATORS"> for details.
2071 =head2 insert($table, \@values || \%fieldvals, \%options)
2073 This is the simplest function. You simply give it a table name
2074 and either an arrayref of values or hashref of field/value pairs.
2075 It returns an SQL INSERT statement and a list of bind values.
2076 See the sections on L</"Inserting and Updating Arrays"> and
2077 L</"Inserting and Updating SQL"> for information on how to insert
2078 with those data types.
2080 The optional C<\%options> hash reference may contain additional
2081 options to generate the insert SQL. Currently supported options
2088 Takes either a scalar of raw SQL fields, or an array reference of
2089 field names, and adds on an SQL C<RETURNING> statement at the end.
2090 This allows you to return data generated by the insert statement
2091 (such as row IDs) without performing another C<SELECT> statement.
2092 Note, however, this is not part of the SQL standard and may not
2093 be supported by all database engines.
2097 =head2 update($table, \%fieldvals, \%where, \%options)
2099 This takes a table, hashref of field/value pairs, and an optional
2100 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
2102 See the sections on L</"Inserting and Updating Arrays"> and
2103 L</"Inserting and Updating SQL"> for information on how to insert
2104 with those data types.
2106 The optional C<\%options> hash reference may contain additional
2107 options to generate the update SQL. Currently supported options
2114 See the C<returning> option to
2115 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2119 =head2 select($source, $fields, $where, $order)
2121 This returns a SQL SELECT statement and associated list of bind values, as
2122 specified by the arguments :
2128 Specification of the 'FROM' part of the statement.
2129 The argument can be either a plain scalar (interpreted as a table
2130 name, will be quoted), or an arrayref (interpreted as a list
2131 of table names, joined by commas, quoted), or a scalarref
2132 (literal table name, not quoted), or a ref to an arrayref
2133 (list of literal table names, joined by commas, not quoted).
2137 Specification of the list of fields to retrieve from
2139 The argument can be either an arrayref (interpreted as a list
2140 of field names, will be joined by commas and quoted), or a
2141 plain scalar (literal SQL, not quoted).
2142 Please observe that this API is not as flexible as that of
2143 the first argument C<$source>, for backwards compatibility reasons.
2147 Optional argument to specify the WHERE part of the query.
2148 The argument is most often a hashref, but can also be
2149 an arrayref or plain scalar --
2150 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2154 Optional argument to specify the ORDER BY part of the query.
2155 The argument can be a scalar, a hashref or an arrayref
2156 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2162 =head2 delete($table, \%where, \%options)
2164 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2165 It returns an SQL DELETE statement and list of bind values.
2167 The optional C<\%options> hash reference may contain additional
2168 options to generate the delete SQL. Currently supported options
2175 See the C<returning> option to
2176 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2180 =head2 where(\%where, $order)
2182 This is used to generate just the WHERE clause. For example,
2183 if you have an arbitrary data structure and know what the
2184 rest of your SQL is going to look like, but want an easy way
2185 to produce a WHERE clause, use this. It returns an SQL WHERE
2186 clause and list of bind values.
2189 =head2 values(\%data)
2191 This just returns the values from the hash C<%data>, in the same
2192 order that would be returned from any of the other above queries.
2193 Using this allows you to markedly speed up your queries if you
2194 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2196 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2198 Warning: This is an experimental method and subject to change.
2200 This returns arbitrarily generated SQL. It's a really basic shortcut.
2201 It will return two different things, depending on return context:
2203 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2204 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2206 These would return the following:
2208 # First calling form
2209 $stmt = "CREATE TABLE test (?, ?)";
2210 @bind = (field1, field2);
2212 # Second calling form
2213 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2215 Depending on what you're trying to do, it's up to you to choose the correct
2216 format. In this example, the second form is what you would want.
2220 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2224 ALTER SESSION SET nls_date_format = 'MM/YY'
2226 You get the idea. Strings get their case twiddled, but everything
2227 else remains verbatim.
2229 =head1 EXPORTABLE FUNCTIONS
2231 =head2 is_plain_value
2233 Determines if the supplied argument is a plain value as understood by this
2238 =item * The value is C<undef>
2240 =item * The value is a non-reference
2242 =item * The value is an object with stringification overloading
2244 =item * The value is of the form C<< { -value => $anything } >>
2248 On failure returns C<undef>, on sucess returns a B<scalar> reference
2249 to the original supplied argument.
2255 The stringification overloading detection is rather advanced: it takes
2256 into consideration not only the presence of a C<""> overload, but if that
2257 fails also checks for enabled
2258 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2259 on either C<0+> or C<bool>.
2261 Unfortunately testing in the field indicates that this
2262 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2263 but only when very large numbers of stringifying objects are involved.
2264 At the time of writing ( Sep 2014 ) there is no clear explanation of
2265 the direct cause, nor is there a manageably small test case that reliably
2266 reproduces the problem.
2268 If you encounter any of the following exceptions in B<random places within
2269 your application stack> - this module may be to blame:
2271 Operation "ne": no method found,
2272 left argument in overloaded package <something>,
2273 right argument in overloaded package <something>
2277 Stub found while resolving method "???" overloading """" in package <something>
2279 If you fall victim to the above - please attempt to reduce the problem
2280 to something that could be sent to the L<SQL::Abstract developers
2281 |DBIx::Class/GETTING HELP/SUPPORT>
2282 (either publicly or privately). As a workaround in the meantime you can
2283 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2284 value, which will most likely eliminate your problem (at the expense of
2285 not being able to properly detect exotic forms of stringification).
2287 This notice and environment variable will be removed in a future version,
2288 as soon as the underlying problem is found and a reliable workaround is
2293 =head2 is_literal_value
2295 Determines if the supplied argument is a literal value as understood by this
2300 =item * C<\$sql_string>
2302 =item * C<\[ $sql_string, @bind_values ]>
2306 On failure returns C<undef>, on sucess returns an B<array> reference
2307 containing the unpacked version of the supplied literal SQL and bind values.
2309 =head1 WHERE CLAUSES
2313 This module uses a variation on the idea from L<DBIx::Abstract>. It
2314 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2315 module is that things in arrays are OR'ed, and things in hashes
2318 The easiest way to explain is to show lots of examples. After
2319 each C<%where> hash shown, it is assumed you used:
2321 my($stmt, @bind) = $sql->where(\%where);
2323 However, note that the C<%where> hash can be used directly in any
2324 of the other functions as well, as described above.
2326 =head2 Key-value pairs
2328 So, let's get started. To begin, a simple hash:
2332 status => 'completed'
2335 Is converted to SQL C<key = val> statements:
2337 $stmt = "WHERE user = ? AND status = ?";
2338 @bind = ('nwiger', 'completed');
2340 One common thing I end up doing is having a list of values that
2341 a field can be in. To do this, simply specify a list inside of
2346 status => ['assigned', 'in-progress', 'pending'];
2349 This simple code will create the following:
2351 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2352 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2354 A field associated to an empty arrayref will be considered a
2355 logical false and will generate 0=1.
2357 =head2 Tests for NULL values
2359 If the value part is C<undef> then this is converted to SQL <IS NULL>
2368 $stmt = "WHERE user = ? AND status IS NULL";
2371 To test if a column IS NOT NULL:
2375 status => { '!=', undef },
2378 =head2 Specific comparison operators
2380 If you want to specify a different type of operator for your comparison,
2381 you can use a hashref for a given column:
2385 status => { '!=', 'completed' }
2388 Which would generate:
2390 $stmt = "WHERE user = ? AND status != ?";
2391 @bind = ('nwiger', 'completed');
2393 To test against multiple values, just enclose the values in an arrayref:
2395 status => { '=', ['assigned', 'in-progress', 'pending'] };
2397 Which would give you:
2399 "WHERE status = ? OR status = ? OR status = ?"
2402 The hashref can also contain multiple pairs, in which case it is expanded
2403 into an C<AND> of its elements:
2407 status => { '!=', 'completed', -not_like => 'pending%' }
2410 # Or more dynamically, like from a form
2411 $where{user} = 'nwiger';
2412 $where{status}{'!='} = 'completed';
2413 $where{status}{'-not_like'} = 'pending%';
2415 # Both generate this
2416 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2417 @bind = ('nwiger', 'completed', 'pending%');
2420 To get an OR instead, you can combine it with the arrayref idea:
2424 priority => [ { '=', 2 }, { '>', 5 } ]
2427 Which would generate:
2429 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2430 @bind = ('2', '5', 'nwiger');
2432 If you want to include literal SQL (with or without bind values), just use a
2433 scalar reference or reference to an arrayref as the value:
2436 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2437 date_expires => { '<' => \"now()" }
2440 Which would generate:
2442 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2443 @bind = ('11/26/2008');
2446 =head2 Logic and nesting operators
2448 In the example above,
2449 there is a subtle trap if you want to say something like
2450 this (notice the C<AND>):
2452 WHERE priority != ? AND priority != ?
2454 Because, in Perl you I<can't> do this:
2456 priority => { '!=' => 2, '!=' => 1 }
2458 As the second C<!=> key will obliterate the first. The solution
2459 is to use the special C<-modifier> form inside an arrayref:
2461 priority => [ -and => {'!=', 2},
2465 Normally, these would be joined by C<OR>, but the modifier tells it
2466 to use C<AND> instead. (Hint: You can use this in conjunction with the
2467 C<logic> option to C<new()> in order to change the way your queries
2468 work by default.) B<Important:> Note that the C<-modifier> goes
2469 B<INSIDE> the arrayref, as an extra first element. This will
2470 B<NOT> do what you think it might:
2472 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2474 Here is a quick list of equivalencies, since there is some overlap:
2477 status => {'!=', 'completed', 'not like', 'pending%' }
2478 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2481 status => {'=', ['assigned', 'in-progress']}
2482 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2483 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2487 =head2 Special operators : IN, BETWEEN, etc.
2489 You can also use the hashref format to compare a list of fields using the
2490 C<IN> comparison operator, by specifying the list as an arrayref:
2493 status => 'completed',
2494 reportid => { -in => [567, 2335, 2] }
2497 Which would generate:
2499 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2500 @bind = ('completed', '567', '2335', '2');
2502 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2505 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2506 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2507 'sqltrue' (by default : C<1=1>).
2509 In addition to the array you can supply a chunk of literal sql or
2510 literal sql with bind:
2513 customer => { -in => \[
2514 'SELECT cust_id FROM cust WHERE balance > ?',
2517 status => { -in => \'SELECT status_codes FROM states' },
2523 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2524 AND status IN ( SELECT status_codes FROM states )
2528 Finally, if the argument to C<-in> is not a reference, it will be
2529 treated as a single-element array.
2531 Another pair of operators is C<-between> and C<-not_between>,
2532 used with an arrayref of two values:
2536 completion_date => {
2537 -not_between => ['2002-10-01', '2003-02-06']
2543 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2545 Just like with C<-in> all plausible combinations of literal SQL
2549 start0 => { -between => [ 1, 2 ] },
2550 start1 => { -between => \["? AND ?", 1, 2] },
2551 start2 => { -between => \"lower(x) AND upper(y)" },
2552 start3 => { -between => [
2554 \["upper(?)", 'stuff' ],
2561 ( start0 BETWEEN ? AND ? )
2562 AND ( start1 BETWEEN ? AND ? )
2563 AND ( start2 BETWEEN lower(x) AND upper(y) )
2564 AND ( start3 BETWEEN lower(x) AND upper(?) )
2566 @bind = (1, 2, 1, 2, 'stuff');
2569 These are the two builtin "special operators"; but the
2570 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2572 =head2 Unary operators: bool
2574 If you wish to test against boolean columns or functions within your
2575 database you can use the C<-bool> and C<-not_bool> operators. For
2576 example to test the column C<is_user> being true and the column
2577 C<is_enabled> being false you would use:-
2581 -not_bool => 'is_enabled',
2586 WHERE is_user AND NOT is_enabled
2588 If a more complex combination is required, testing more conditions,
2589 then you should use the and/or operators:-
2594 -not_bool => { two=> { -rlike => 'bar' } },
2595 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2606 (NOT ( three = ? OR three > ? ))
2609 =head2 Nested conditions, -and/-or prefixes
2611 So far, we've seen how multiple conditions are joined with a top-level
2612 C<AND>. We can change this by putting the different conditions we want in
2613 hashes and then putting those hashes in an array. For example:
2618 status => { -like => ['pending%', 'dispatched'] },
2622 status => 'unassigned',
2626 This data structure would create the following:
2628 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2629 OR ( user = ? AND status = ? ) )";
2630 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2633 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2634 to change the logic inside :
2640 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2641 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2648 $stmt = "WHERE ( user = ?
2649 AND ( ( workhrs > ? AND geo = ? )
2650 OR ( workhrs < ? OR geo = ? ) ) )";
2651 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2653 =head3 Algebraic inconsistency, for historical reasons
2655 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2656 operator goes C<outside> of the nested structure; whereas when connecting
2657 several constraints on one column, the C<-and> operator goes
2658 C<inside> the arrayref. Here is an example combining both features :
2661 -and => [a => 1, b => 2],
2662 -or => [c => 3, d => 4],
2663 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2668 WHERE ( ( ( a = ? AND b = ? )
2669 OR ( c = ? OR d = ? )
2670 OR ( e LIKE ? AND e LIKE ? ) ) )
2672 This difference in syntax is unfortunate but must be preserved for
2673 historical reasons. So be careful : the two examples below would
2674 seem algebraically equivalent, but they are not
2677 { -like => 'foo%' },
2678 { -like => '%bar' },
2680 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2683 { col => { -like => 'foo%' } },
2684 { col => { -like => '%bar' } },
2686 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2689 =head2 Literal SQL and value type operators
2691 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2692 side" is a column name and the "right side" is a value (normally rendered as
2693 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2694 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2695 alter this behavior. There are several ways of doing so.
2699 This is a virtual operator that signals the string to its right side is an
2700 identifier (a column name) and not a value. For example to compare two
2701 columns you would write:
2704 priority => { '<', 2 },
2705 requestor => { -ident => 'submitter' },
2710 $stmt = "WHERE priority < ? AND requestor = submitter";
2713 If you are maintaining legacy code you may see a different construct as
2714 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2719 This is a virtual operator that signals that the construct to its right side
2720 is a value to be passed to DBI. This is for example necessary when you want
2721 to write a where clause against an array (for RDBMS that support such
2722 datatypes). For example:
2725 array => { -value => [1, 2, 3] }
2730 $stmt = 'WHERE array = ?';
2731 @bind = ([1, 2, 3]);
2733 Note that if you were to simply say:
2739 the result would probably not be what you wanted:
2741 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2746 Finally, sometimes only literal SQL will do. To include a random snippet
2747 of SQL verbatim, you specify it as a scalar reference. Consider this only
2748 as a last resort. Usually there is a better way. For example:
2751 priority => { '<', 2 },
2752 requestor => { -in => \'(SELECT name FROM hitmen)' },
2757 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2760 Note that in this example, you only get one bind parameter back, since
2761 the verbatim SQL is passed as part of the statement.
2765 Never use untrusted input as a literal SQL argument - this is a massive
2766 security risk (there is no way to check literal snippets for SQL
2767 injections and other nastyness). If you need to deal with untrusted input
2768 use literal SQL with placeholders as described next.
2770 =head3 Literal SQL with placeholders and bind values (subqueries)
2772 If the literal SQL to be inserted has placeholders and bind values,
2773 use a reference to an arrayref (yes this is a double reference --
2774 not so common, but perfectly legal Perl). For example, to find a date
2775 in Postgres you can use something like this:
2778 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2783 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2786 Note that you must pass the bind values in the same format as they are returned
2787 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2788 to C<columns>, you must provide the bind values in the
2789 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2790 scalar value; most commonly the column name, but you can use any scalar value
2791 (including references and blessed references), L<SQL::Abstract> will simply
2792 pass it through intact. So if C<bindtype> is set to C<columns> the above
2793 example will look like:
2796 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2799 Literal SQL is especially useful for nesting parenthesized clauses in the
2800 main SQL query. Here is a first example :
2802 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2806 bar => \["IN ($sub_stmt)" => @sub_bind],
2811 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2812 WHERE c2 < ? AND c3 LIKE ?))";
2813 @bind = (1234, 100, "foo%");
2815 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2816 are expressed in the same way. Of course the C<$sub_stmt> and
2817 its associated bind values can be generated through a former call
2820 my ($sub_stmt, @sub_bind)
2821 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2822 c3 => {-like => "foo%"}});
2825 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2828 In the examples above, the subquery was used as an operator on a column;
2829 but the same principle also applies for a clause within the main C<%where>
2830 hash, like an EXISTS subquery :
2832 my ($sub_stmt, @sub_bind)
2833 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2834 my %where = ( -and => [
2836 \["EXISTS ($sub_stmt)" => @sub_bind],
2841 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2842 WHERE c1 = ? AND c2 > t0.c0))";
2846 Observe that the condition on C<c2> in the subquery refers to
2847 column C<t0.c0> of the main query : this is I<not> a bind
2848 value, so we have to express it through a scalar ref.
2849 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2850 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2851 what we wanted here.
2853 Finally, here is an example where a subquery is used
2854 for expressing unary negation:
2856 my ($sub_stmt, @sub_bind)
2857 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2858 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2860 lname => {like => '%son%'},
2861 \["NOT ($sub_stmt)" => @sub_bind],
2866 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2867 @bind = ('%son%', 10, 20)
2869 =head3 Deprecated usage of Literal SQL
2871 Below are some examples of archaic use of literal SQL. It is shown only as
2872 reference for those who deal with legacy code. Each example has a much
2873 better, cleaner and safer alternative that users should opt for in new code.
2879 my %where = ( requestor => \'IS NOT NULL' )
2881 $stmt = "WHERE requestor IS NOT NULL"
2883 This used to be the way of generating NULL comparisons, before the handling
2884 of C<undef> got formalized. For new code please use the superior syntax as
2885 described in L</Tests for NULL values>.
2889 my %where = ( requestor => \'= submitter' )
2891 $stmt = "WHERE requestor = submitter"
2893 This used to be the only way to compare columns. Use the superior L</-ident>
2894 method for all new code. For example an identifier declared in such a way
2895 will be properly quoted if L</quote_char> is properly set, while the legacy
2896 form will remain as supplied.
2900 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2902 $stmt = "WHERE completed > ? AND is_ready"
2903 @bind = ('2012-12-21')
2905 Using an empty string literal used to be the only way to express a boolean.
2906 For all new code please use the much more readable
2907 L<-bool|/Unary operators: bool> operator.
2913 These pages could go on for a while, since the nesting of the data
2914 structures this module can handle are pretty much unlimited (the
2915 module implements the C<WHERE> expansion as a recursive function
2916 internally). Your best bet is to "play around" with the module a
2917 little to see how the data structures behave, and choose the best
2918 format for your data based on that.
2920 And of course, all the values above will probably be replaced with
2921 variables gotten from forms or the command line. After all, if you
2922 knew everything ahead of time, you wouldn't have to worry about
2923 dynamically-generating SQL and could just hardwire it into your
2926 =head1 ORDER BY CLAUSES
2928 Some functions take an order by clause. This can either be a scalar (just a
2929 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2930 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2933 Given | Will Generate
2934 ---------------------------------------------------------------
2936 'colA' | ORDER BY colA
2938 [qw/colA colB/] | ORDER BY colA, colB
2940 {-asc => 'colA'} | ORDER BY colA ASC
2942 {-desc => 'colB'} | ORDER BY colB DESC
2944 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2946 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2948 \'colA DESC' | ORDER BY colA DESC
2950 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2951 | /* ...with $x bound to ? */
2954 { -asc => 'colA' }, | colA ASC,
2955 { -desc => [qw/colB/] }, | colB DESC,
2956 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2957 \'colE DESC', | colE DESC,
2958 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2959 ] | /* ...with $x bound to ? */
2960 ===============================================================
2964 =head1 SPECIAL OPERATORS
2966 my $sqlmaker = SQL::Abstract->new(special_ops => [
2970 my ($self, $field, $op, $arg) = @_;
2976 handler => 'method_name',
2980 A "special operator" is a SQL syntactic clause that can be
2981 applied to a field, instead of a usual binary operator.
2984 WHERE field IN (?, ?, ?)
2985 WHERE field BETWEEN ? AND ?
2986 WHERE MATCH(field) AGAINST (?, ?)
2988 Special operators IN and BETWEEN are fairly standard and therefore
2989 are builtin within C<SQL::Abstract> (as the overridable methods
2990 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2991 like the MATCH .. AGAINST example above which is specific to MySQL,
2992 you can write your own operator handlers - supply a C<special_ops>
2993 argument to the C<new> method. That argument takes an arrayref of
2994 operator definitions; each operator definition is a hashref with two
3001 the regular expression to match the operator
3005 Either a coderef or a plain scalar method name. In both cases
3006 the expected return is C<< ($sql, @bind) >>.
3008 When supplied with a method name, it is simply called on the
3009 L<SQL::Abstract> object as:
3011 $self->$method_name ($field, $op, $arg)
3015 $field is the LHS of the operator
3016 $op is the part that matched the handler regex
3019 When supplied with a coderef, it is called as:
3021 $coderef->($self, $field, $op, $arg)
3026 For example, here is an implementation
3027 of the MATCH .. AGAINST syntax for MySQL
3029 my $sqlmaker = SQL::Abstract->new(special_ops => [
3031 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
3032 {regex => qr/^match$/i,
3034 my ($self, $field, $op, $arg) = @_;
3035 $arg = [$arg] if not ref $arg;
3036 my $label = $self->_quote($field);
3037 my ($placeholder) = $self->_convert('?');
3038 my $placeholders = join ", ", (($placeholder) x @$arg);
3039 my $sql = $self->_sqlcase('match') . " ($label) "
3040 . $self->_sqlcase('against') . " ($placeholders) ";
3041 my @bind = $self->_bindtype($field, @$arg);
3042 return ($sql, @bind);
3049 =head1 UNARY OPERATORS
3051 my $sqlmaker = SQL::Abstract->new(unary_ops => [
3055 my ($self, $op, $arg) = @_;
3061 handler => 'method_name',
3065 A "unary operator" is a SQL syntactic clause that can be
3066 applied to a field - the operator goes before the field
3068 You can write your own operator handlers - supply a C<unary_ops>
3069 argument to the C<new> method. That argument takes an arrayref of
3070 operator definitions; each operator definition is a hashref with two
3077 the regular expression to match the operator
3081 Either a coderef or a plain scalar method name. In both cases
3082 the expected return is C<< $sql >>.
3084 When supplied with a method name, it is simply called on the
3085 L<SQL::Abstract> object as:
3087 $self->$method_name ($op, $arg)
3091 $op is the part that matched the handler regex
3092 $arg is the RHS or argument of the operator
3094 When supplied with a coderef, it is called as:
3096 $coderef->($self, $op, $arg)
3104 Thanks to some benchmarking by Mark Stosberg, it turns out that
3105 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
3106 I must admit this wasn't an intentional design issue, but it's a
3107 byproduct of the fact that you get to control your C<DBI> handles
3110 To maximize performance, use a code snippet like the following:
3112 # prepare a statement handle using the first row
3113 # and then reuse it for the rest of the rows
3115 for my $href (@array_of_hashrefs) {
3116 $stmt ||= $sql->insert('table', $href);
3117 $sth ||= $dbh->prepare($stmt);
3118 $sth->execute($sql->values($href));
3121 The reason this works is because the keys in your C<$href> are sorted
3122 internally by B<SQL::Abstract>. Thus, as long as your data retains
3123 the same structure, you only have to generate the SQL the first time
3124 around. On subsequent queries, simply use the C<values> function provided
3125 by this module to return your values in the correct order.
3127 However this depends on the values having the same type - if, for
3128 example, the values of a where clause may either have values
3129 (resulting in sql of the form C<column = ?> with a single bind
3130 value), or alternatively the values might be C<undef> (resulting in
3131 sql of the form C<column IS NULL> with no bind value) then the
3132 caching technique suggested will not work.
3136 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3137 really like this part (I do, at least). Building up a complex query
3138 can be as simple as the following:
3145 use CGI::FormBuilder;
3148 my $form = CGI::FormBuilder->new(...);
3149 my $sql = SQL::Abstract->new;
3151 if ($form->submitted) {
3152 my $field = $form->field;
3153 my $id = delete $field->{id};
3154 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3157 Of course, you would still have to connect using C<DBI> to run the
3158 query, but the point is that if you make your form look like your
3159 table, the actual query script can be extremely simplistic.
3161 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3162 a fast interface to returning and formatting data. I frequently
3163 use these three modules together to write complex database query
3164 apps in under 50 lines.
3166 =head1 HOW TO CONTRIBUTE
3168 Contributions are always welcome, in all usable forms (we especially
3169 welcome documentation improvements). The delivery methods include git-
3170 or unified-diff formatted patches, GitHub pull requests, or plain bug
3171 reports either via RT or the Mailing list. Contributors are generally
3172 granted full access to the official repository after their first several
3173 patches pass successful review.
3175 This project is maintained in a git repository. The code and related tools are
3176 accessible at the following locations:
3180 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3182 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3184 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3186 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3192 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3193 Great care has been taken to preserve the I<published> behavior
3194 documented in previous versions in the 1.* family; however,
3195 some features that were previously undocumented, or behaved
3196 differently from the documentation, had to be changed in order
3197 to clarify the semantics. Hence, client code that was relying
3198 on some dark areas of C<SQL::Abstract> v1.*
3199 B<might behave differently> in v1.50.
3201 The main changes are :
3207 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3211 support for the { operator => \"..." } construct (to embed literal SQL)
3215 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3219 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3223 defensive programming : check arguments
3227 fixed bug with global logic, which was previously implemented
3228 through global variables yielding side-effects. Prior versions would
3229 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3230 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3231 Now this is interpreted
3232 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3237 fixed semantics of _bindtype on array args
3241 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3242 we just avoid shifting arrays within that tree.
3246 dropped the C<_modlogic> function
3250 =head1 ACKNOWLEDGEMENTS
3252 There are a number of individuals that have really helped out with
3253 this module. Unfortunately, most of them submitted bugs via CPAN
3254 so I have no idea who they are! But the people I do know are:
3256 Ash Berlin (order_by hash term support)
3257 Matt Trout (DBIx::Class support)
3258 Mark Stosberg (benchmarking)
3259 Chas Owens (initial "IN" operator support)
3260 Philip Collins (per-field SQL functions)
3261 Eric Kolve (hashref "AND" support)
3262 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3263 Dan Kubb (support for "quote_char" and "name_sep")
3264 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3265 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3266 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3267 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3268 Oliver Charles (support for "RETURNING" after "INSERT")
3274 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3278 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3280 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3282 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3283 While not an official support venue, C<DBIx::Class> makes heavy use of
3284 C<SQL::Abstract>, and as such list members there are very familiar with
3285 how to create queries.
3289 This module is free software; you may copy this under the same
3290 terms as perl itself (either the GNU General Public License or
3291 the Artistic License)