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 = '1.81';
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" . $where_sql;
480 return wantarray ? ($sql, @bind) : $sql;
484 #======================================================================
486 #======================================================================
490 # Finally, a separate routine just to handle WHERE clauses
492 my ($self, $where, $order) = @_;
495 my ($sql, @bind) = $self->_recurse_where($where);
496 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
500 my ($order_sql, @order_bind) = $self->_order_by($order);
502 push @bind, @order_bind;
505 return wantarray ? ($sql, @bind) : $sql;
510 my ($self, $where, $logic) = @_;
512 # dispatch on appropriate method according to refkind of $where
513 my $method = $self->_METHOD_FOR_refkind("_where", $where);
515 my ($sql, @bind) = $self->$method($where, $logic);
517 # DBIx::Class used to call _recurse_where in scalar context
518 # something else might too...
520 return ($sql, @bind);
523 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
530 #======================================================================
531 # WHERE: top-level ARRAYREF
532 #======================================================================
535 sub _where_ARRAYREF {
536 my ($self, $where, $logic) = @_;
538 $logic = uc($logic || $self->{logic});
539 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
541 my @clauses = @$where;
543 my (@sql_clauses, @all_bind);
544 # need to use while() so can shift() for pairs
546 my $el = shift @clauses;
548 $el = undef if (defined $el and ! length $el);
550 # switch according to kind of $el and get corresponding ($sql, @bind)
551 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
553 # skip empty elements, otherwise get invalid trailing AND stuff
554 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
558 $self->_assert_bindval_matches_bindtype(@b);
562 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
564 SCALARREF => sub { ($$el); },
567 # top-level arrayref with scalars, recurse in pairs
568 $self->_recurse_where({$el => shift(@clauses)})
571 UNDEF => sub {puke "Supplying an empty left hand side argument is not supported in array-pairs" },
575 push @sql_clauses, $sql;
576 push @all_bind, @bind;
580 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
583 #======================================================================
584 # WHERE: top-level ARRAYREFREF
585 #======================================================================
587 sub _where_ARRAYREFREF {
588 my ($self, $where) = @_;
589 my ($sql, @bind) = @$$where;
590 $self->_assert_bindval_matches_bindtype(@bind);
591 return ($sql, @bind);
594 #======================================================================
595 # WHERE: top-level HASHREF
596 #======================================================================
599 my ($self, $where) = @_;
600 my (@sql_clauses, @all_bind);
602 for my $k (sort keys %$where) {
603 my $v = $where->{$k};
605 # ($k => $v) is either a special unary op or a regular hashpair
606 my ($sql, @bind) = do {
608 # put the operator in canonical form
610 $op = substr $op, 1; # remove initial dash
611 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
612 $op =~ s/\s+/ /g; # compress whitespace
614 # so that -not_foo works correctly
615 $op =~ s/^not_/NOT /i;
617 $self->_debug("Unary OP(-$op) within hashref, recursing...");
618 my ($s, @b) = $self->_where_unary_op ($op, $v);
620 # top level vs nested
621 # we assume that handled unary ops will take care of their ()s
623 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
625 ( defined $self->{_nested_func_lhs} and $self->{_nested_func_lhs} eq $k )
631 if (is_literal_value ($v) ) {
632 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
635 puke "Supplying an empty left hand side argument is not supported in hash-pairs";
639 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
640 $self->$method($k, $v);
644 push @sql_clauses, $sql;
645 push @all_bind, @bind;
648 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
651 sub _where_unary_op {
652 my ($self, $op, $rhs) = @_;
654 # top level special ops are illegal in general
655 # this includes the -ident/-value ops (dual purpose unary and special)
656 puke "Illegal use of top-level '-$op'"
657 if ! defined $self->{_nested_func_lhs} and List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}};
659 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
660 my $handler = $op_entry->{handler};
662 if (not ref $handler) {
663 if ($op =~ s/ [_\s]? \d+ $//x ) {
664 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
665 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
667 return $self->$handler ($op, $rhs);
669 elsif (ref $handler eq 'CODE') {
670 return $handler->($self, $op, $rhs);
673 puke "Illegal handler for operator $op - expecting a method name or a coderef";
677 $self->_debug("Generic unary OP: $op - recursing as function");
679 $self->_assert_pass_injection_guard($op);
681 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
683 puke "Illegal use of top-level '-$op'"
684 unless defined $self->{_nested_func_lhs};
687 $self->_convert('?'),
688 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
692 $self->_recurse_where ($rhs)
696 $sql = sprintf ('%s %s',
697 $self->_sqlcase($op),
701 return ($sql, @bind);
704 sub _where_op_ANDOR {
705 my ($self, $op, $v) = @_;
707 $self->_SWITCH_refkind($v, {
709 return $self->_where_ARRAYREF($v, $op);
713 return ( $op =~ /^or/i )
714 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
715 : $self->_where_HASHREF($v);
719 puke "-$op => \\\$scalar makes little sense, use " .
721 ? '[ \$scalar, \%rest_of_conditions ] instead'
722 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
727 puke "-$op => \\[...] makes little sense, use " .
729 ? '[ \[...], \%rest_of_conditions ] instead'
730 : '-and => [ \[...], \%rest_of_conditions ] instead'
734 SCALAR => sub { # permissively interpreted as SQL
735 puke "-$op => \$value makes little sense, use -bool => \$value instead";
739 puke "-$op => undef not supported";
745 my ($self, $op, $v) = @_;
747 $self->_SWITCH_refkind($v, {
749 SCALAR => sub { # permissively interpreted as SQL
750 belch "literal SQL should be -nest => \\'scalar' "
751 . "instead of -nest => 'scalar' ";
756 puke "-$op => undef not supported";
760 $self->_recurse_where ($v);
768 my ($self, $op, $v) = @_;
770 my ($s, @b) = $self->_SWITCH_refkind($v, {
771 SCALAR => sub { # interpreted as SQL column
772 $self->_convert($self->_quote($v));
776 puke "-$op => undef not supported";
780 $self->_recurse_where ($v);
784 $s = "(NOT $s)" if $op =~ /^not/i;
789 sub _where_op_IDENT {
791 my ($op, $rhs) = splice @_, -2;
792 if (! defined $rhs or length ref $rhs) {
793 puke "-$op requires a single plain scalar argument (a quotable identifier)";
796 # in case we are called as a top level special op (no '=')
799 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
807 sub _where_op_VALUE {
809 my ($op, $rhs) = splice @_, -2;
811 # in case we are called as a top level special op (no '=')
815 if (! defined $rhs) {
817 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
824 ( defined $lhs ? $lhs : $self->{_nested_func_lhs} ),
831 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
835 $self->_convert('?'),
841 sub _where_hashpair_ARRAYREF {
842 my ($self, $k, $v) = @_;
845 my @v = @$v; # need copy because of shift below
846 $self->_debug("ARRAY($k) means distribute over elements");
848 # put apart first element if it is an operator (-and, -or)
850 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
854 my @distributed = map { {$k => $_} } @v;
857 $self->_debug("OP($op) reinjected into the distributed array");
858 unshift @distributed, $op;
861 my $logic = $op ? substr($op, 1) : '';
863 return $self->_recurse_where(\@distributed, $logic);
866 $self->_debug("empty ARRAY($k) means 0=1");
867 return ($self->{sqlfalse});
871 sub _where_hashpair_HASHREF {
872 my ($self, $k, $v, $logic) = @_;
875 local $self->{_nested_func_lhs} = defined $self->{_nested_func_lhs}
876 ? $self->{_nested_func_lhs}
880 my ($all_sql, @all_bind);
882 for my $orig_op (sort keys %$v) {
883 my $val = $v->{$orig_op};
885 # put the operator in canonical form
888 # FIXME - we need to phase out dash-less ops
889 $op =~ s/^-//; # remove possible initial dash
890 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
891 $op =~ s/\s+/ /g; # compress whitespace
893 $self->_assert_pass_injection_guard($op);
896 $op =~ s/^is_not/IS NOT/i;
898 # so that -not_foo works correctly
899 $op =~ s/^not_/NOT /i;
901 # another retarded special case: foo => { $op => { -value => undef } }
902 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
908 # CASE: col-value logic modifiers
909 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
910 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
912 # CASE: special operators like -in or -between
913 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
914 my $handler = $special_op->{handler};
916 puke "No handler supplied for special operator $orig_op";
918 elsif (not ref $handler) {
919 ($sql, @bind) = $self->$handler ($k, $op, $val);
921 elsif (ref $handler eq 'CODE') {
922 ($sql, @bind) = $handler->($self, $k, $op, $val);
925 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
929 $self->_SWITCH_refkind($val, {
931 ARRAYREF => sub { # CASE: col => {op => \@vals}
932 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
935 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
936 my ($sub_sql, @sub_bind) = @$$val;
937 $self->_assert_bindval_matches_bindtype(@sub_bind);
938 $sql = join ' ', $self->_convert($self->_quote($k)),
939 $self->_sqlcase($op),
944 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
946 $op =~ /^not$/i ? 'is not' # legacy
947 : $op =~ $self->{equality_op} ? 'is'
948 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
949 : $op =~ $self->{inequality_op} ? 'is not'
950 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
951 : puke "unexpected operator '$orig_op' with undef operand";
953 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
956 FALLBACK => sub { # CASE: col => {op/func => $stuff}
957 ($sql, @bind) = $self->_where_unary_op ($op, $val);
960 $self->_convert($self->_quote($k)),
961 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
967 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
968 push @all_bind, @bind;
970 return ($all_sql, @all_bind);
973 sub _where_field_IS {
974 my ($self, $k, $op, $v) = @_;
976 my ($s) = $self->_SWITCH_refkind($v, {
979 $self->_convert($self->_quote($k)),
980 map { $self->_sqlcase($_)} ($op, 'null')
983 puke "$op can only take undef as argument";
990 sub _where_field_op_ARRAYREF {
991 my ($self, $k, $op, $vals) = @_;
993 my @vals = @$vals; #always work on a copy
996 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
998 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
1001 # see if the first element is an -and/-or op
1003 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
1008 # a long standing API wart - an attempt to change this behavior during
1009 # the 1.50 series failed *spectacularly*. Warn instead and leave the
1014 (!$logic or $logic eq 'OR')
1016 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
1019 belch "A multi-element arrayref as an argument to the inequality op '$o' "
1020 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
1021 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
1025 # distribute $op over each remaining member of @vals, append logic if exists
1026 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
1030 # try to DWIM on equality operators
1032 $op =~ $self->{equality_op} ? $self->{sqlfalse}
1033 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
1034 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
1035 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
1036 : puke "operator '$op' applied on an empty array (field '$k')";
1041 sub _where_hashpair_SCALARREF {
1042 my ($self, $k, $v) = @_;
1043 $self->_debug("SCALAR($k) means literal SQL: $$v");
1044 my $sql = $self->_quote($k) . " " . $$v;
1048 # literal SQL with bind
1049 sub _where_hashpair_ARRAYREFREF {
1050 my ($self, $k, $v) = @_;
1051 $self->_debug("REF($k) means literal SQL: @${$v}");
1052 my ($sql, @bind) = @$$v;
1053 $self->_assert_bindval_matches_bindtype(@bind);
1054 $sql = $self->_quote($k) . " " . $sql;
1055 return ($sql, @bind );
1058 # literal SQL without bind
1059 sub _where_hashpair_SCALAR {
1060 my ($self, $k, $v) = @_;
1061 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
1062 my $sql = join ' ', $self->_convert($self->_quote($k)),
1063 $self->_sqlcase($self->{cmp}),
1064 $self->_convert('?');
1065 my @bind = $self->_bindtype($k, $v);
1066 return ( $sql, @bind);
1070 sub _where_hashpair_UNDEF {
1071 my ($self, $k, $v) = @_;
1072 $self->_debug("UNDEF($k) means IS NULL");
1073 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
1077 #======================================================================
1078 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
1079 #======================================================================
1082 sub _where_SCALARREF {
1083 my ($self, $where) = @_;
1086 $self->_debug("SCALAR(*top) means literal SQL: $$where");
1092 my ($self, $where) = @_;
1095 $self->_debug("NOREF(*top) means literal SQL: $where");
1106 #======================================================================
1107 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
1108 #======================================================================
1111 sub _where_field_BETWEEN {
1112 my ($self, $k, $op, $vals) = @_;
1114 my ($label, $and, $placeholder);
1115 $label = $self->_convert($self->_quote($k));
1116 $and = ' ' . $self->_sqlcase('and') . ' ';
1117 $placeholder = $self->_convert('?');
1118 $op = $self->_sqlcase($op);
1120 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1122 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1123 ARRAYREFREF => sub {
1124 my ($s, @b) = @$$vals;
1125 $self->_assert_bindval_matches_bindtype(@b);
1132 puke $invalid_args if @$vals != 2;
1134 my (@all_sql, @all_bind);
1135 foreach my $val (@$vals) {
1136 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1138 return ($placeholder, $self->_bindtype($k, $val) );
1143 ARRAYREFREF => sub {
1144 my ($sql, @bind) = @$$val;
1145 $self->_assert_bindval_matches_bindtype(@bind);
1146 return ($sql, @bind);
1149 my ($func, $arg, @rest) = %$val;
1150 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1151 if (@rest or $func !~ /^ \- (.+)/x);
1152 $self->_where_unary_op ($1 => $arg);
1158 push @all_sql, $sql;
1159 push @all_bind, @bind;
1163 (join $and, @all_sql),
1172 my $sql = "( $label $op $clause )";
1173 return ($sql, @bind)
1177 sub _where_field_IN {
1178 my ($self, $k, $op, $vals) = @_;
1180 # backwards compatibility : if scalar, force into an arrayref
1181 $vals = [$vals] if defined $vals && ! ref $vals;
1183 my ($label) = $self->_convert($self->_quote($k));
1184 my ($placeholder) = $self->_convert('?');
1185 $op = $self->_sqlcase($op);
1187 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1188 ARRAYREF => sub { # list of choices
1189 if (@$vals) { # nonempty list
1190 my (@all_sql, @all_bind);
1192 for my $val (@$vals) {
1193 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1195 return ($placeholder, $val);
1200 ARRAYREFREF => sub {
1201 my ($sql, @bind) = @$$val;
1202 $self->_assert_bindval_matches_bindtype(@bind);
1203 return ($sql, @bind);
1206 my ($func, $arg, @rest) = %$val;
1207 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1208 if (@rest or $func !~ /^ \- (.+)/x);
1209 $self->_where_unary_op ($1 => $arg);
1213 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1214 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1215 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1216 . 'will emit the logically correct SQL instead of raising this exception)'
1220 push @all_sql, $sql;
1221 push @all_bind, @bind;
1225 sprintf ('%s %s ( %s )',
1228 join (', ', @all_sql)
1230 $self->_bindtype($k, @all_bind),
1233 else { # empty list : some databases won't understand "IN ()", so DWIM
1234 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1239 SCALARREF => sub { # literal SQL
1240 my $sql = $self->_open_outer_paren ($$vals);
1241 return ("$label $op ( $sql )");
1243 ARRAYREFREF => sub { # literal SQL with bind
1244 my ($sql, @bind) = @$$vals;
1245 $self->_assert_bindval_matches_bindtype(@bind);
1246 $sql = $self->_open_outer_paren ($sql);
1247 return ("$label $op ( $sql )", @bind);
1251 puke "Argument passed to the '$op' operator can not be undefined";
1255 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1259 return ($sql, @bind);
1262 # Some databases (SQLite) treat col IN (1, 2) different from
1263 # col IN ( (1, 2) ). Use this to strip all outer parens while
1264 # adding them back in the corresponding method
1265 sub _open_outer_paren {
1266 my ($self, $sql) = @_;
1268 while ( my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs ) {
1270 # there are closing parens inside, need the heavy duty machinery
1271 # to reevaluate the extraction starting from $sql (full reevaluation)
1272 if ( $inner =~ /\)/ ) {
1273 require Text::Balanced;
1275 my (undef, $remainder) = do {
1276 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1278 Text::Balanced::extract_bracketed( $sql, '()', qr/\s*/ );
1281 # the entire expression needs to be a balanced bracketed thing
1282 # (after an extract no remainder sans trailing space)
1283 last if defined $remainder and $remainder =~ /\S/;
1293 #======================================================================
1295 #======================================================================
1298 my ($self, $arg) = @_;
1301 for my $c ($self->_order_by_chunks ($arg) ) {
1302 $self->_SWITCH_refkind ($c, {
1303 SCALAR => sub { push @sql, $c },
1304 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1310 $self->_sqlcase(' order by'),
1316 return wantarray ? ($sql, @bind) : $sql;
1319 sub _order_by_chunks {
1320 my ($self, $arg) = @_;
1322 return $self->_SWITCH_refkind($arg, {
1325 map { $self->_order_by_chunks ($_ ) } @$arg;
1328 ARRAYREFREF => sub {
1329 my ($s, @b) = @$$arg;
1330 $self->_assert_bindval_matches_bindtype(@b);
1334 SCALAR => sub {$self->_quote($arg)},
1336 UNDEF => sub {return () },
1338 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1341 # get first pair in hash
1342 my ($key, $val, @rest) = %$arg;
1344 return () unless $key;
1346 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1347 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1353 for my $c ($self->_order_by_chunks ($val)) {
1356 $self->_SWITCH_refkind ($c, {
1361 ($sql, @bind) = @$c;
1365 $sql = $sql . ' ' . $self->_sqlcase($direction);
1367 push @ret, [ $sql, @bind];
1376 #======================================================================
1377 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1378 #======================================================================
1383 $self->_SWITCH_refkind($from, {
1384 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1385 SCALAR => sub {$self->_quote($from)},
1386 SCALARREF => sub {$$from},
1391 #======================================================================
1393 #======================================================================
1395 # highly optimized, as it's called way too often
1397 # my ($self, $label) = @_;
1399 return '' unless defined $_[1];
1400 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1402 $_[0]->{quote_char} or
1403 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1405 my $qref = ref $_[0]->{quote_char};
1407 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1408 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1409 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1411 my $esc = $_[0]->{escape_char} || $r;
1413 # parts containing * are naturally unquoted
1414 return join( $_[0]->{name_sep}||'', map
1415 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1416 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1421 # Conversion, if applicable
1423 #my ($self, $arg) = @_;
1424 if ($_[0]->{convert}) {
1425 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1432 #my ($self, $col, @vals) = @_;
1433 # called often - tighten code
1434 return $_[0]->{bindtype} eq 'columns'
1435 ? map {[$_[1], $_]} @_[2 .. $#_]
1440 # Dies if any element of @bind is not in [colname => value] format
1441 # if bindtype is 'columns'.
1442 sub _assert_bindval_matches_bindtype {
1443 # my ($self, @bind) = @_;
1445 if ($self->{bindtype} eq 'columns') {
1447 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1448 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1454 sub _join_sql_clauses {
1455 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1457 if (@$clauses_aref > 1) {
1458 my $join = " " . $self->_sqlcase($logic) . " ";
1459 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1460 return ($sql, @$bind_aref);
1462 elsif (@$clauses_aref) {
1463 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1466 return (); # if no SQL, ignore @$bind_aref
1471 # Fix SQL case, if so requested
1473 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1474 # don't touch the argument ... crooked logic, but let's not change it!
1475 return $_[0]->{case} ? $_[1] : uc($_[1]);
1479 #======================================================================
1480 # DISPATCHING FROM REFKIND
1481 #======================================================================
1484 my ($self, $data) = @_;
1486 return 'UNDEF' unless defined $data;
1488 # blessed objects are treated like scalars
1489 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1491 return 'SCALAR' unless $ref;
1494 while ($ref eq 'REF') {
1496 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1500 return ($ref||'SCALAR') . ('REF' x $n_steps);
1504 my ($self, $data) = @_;
1505 my @try = ($self->_refkind($data));
1506 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1507 push @try, 'FALLBACK';
1511 sub _METHOD_FOR_refkind {
1512 my ($self, $meth_prefix, $data) = @_;
1515 for (@{$self->_try_refkind($data)}) {
1516 $method = $self->can($meth_prefix."_".$_)
1520 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1524 sub _SWITCH_refkind {
1525 my ($self, $data, $dispatch_table) = @_;
1528 for (@{$self->_try_refkind($data)}) {
1529 $coderef = $dispatch_table->{$_}
1533 puke "no dispatch entry for ".$self->_refkind($data)
1542 #======================================================================
1543 # VALUES, GENERATE, AUTOLOAD
1544 #======================================================================
1546 # LDNOTE: original code from nwiger, didn't touch code in that section
1547 # I feel the AUTOLOAD stuff should not be the default, it should
1548 # only be activated on explicit demand by user.
1552 my $data = shift || return;
1553 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1554 unless ref $data eq 'HASH';
1557 foreach my $k ( sort keys %$data ) {
1558 my $v = $data->{$k};
1559 $self->_SWITCH_refkind($v, {
1561 if ($self->{array_datatypes}) { # array datatype
1562 push @all_bind, $self->_bindtype($k, $v);
1564 else { # literal SQL with bind
1565 my ($sql, @bind) = @$v;
1566 $self->_assert_bindval_matches_bindtype(@bind);
1567 push @all_bind, @bind;
1570 ARRAYREFREF => sub { # literal SQL with bind
1571 my ($sql, @bind) = @${$v};
1572 $self->_assert_bindval_matches_bindtype(@bind);
1573 push @all_bind, @bind;
1575 SCALARREF => sub { # literal SQL without bind
1577 SCALAR_or_UNDEF => sub {
1578 push @all_bind, $self->_bindtype($k, $v);
1589 my(@sql, @sqlq, @sqlv);
1593 if ($ref eq 'HASH') {
1594 for my $k (sort keys %$_) {
1597 my $label = $self->_quote($k);
1598 if ($r eq 'ARRAY') {
1599 # literal SQL with bind
1600 my ($sql, @bind) = @$v;
1601 $self->_assert_bindval_matches_bindtype(@bind);
1602 push @sqlq, "$label = $sql";
1604 } elsif ($r eq 'SCALAR') {
1605 # literal SQL without bind
1606 push @sqlq, "$label = $$v";
1608 push @sqlq, "$label = ?";
1609 push @sqlv, $self->_bindtype($k, $v);
1612 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1613 } elsif ($ref eq 'ARRAY') {
1614 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1617 if ($r eq 'ARRAY') { # literal SQL with bind
1618 my ($sql, @bind) = @$v;
1619 $self->_assert_bindval_matches_bindtype(@bind);
1622 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1623 # embedded literal SQL
1630 push @sql, '(' . join(', ', @sqlq) . ')';
1631 } elsif ($ref eq 'SCALAR') {
1635 # strings get case twiddled
1636 push @sql, $self->_sqlcase($_);
1640 my $sql = join ' ', @sql;
1642 # this is pretty tricky
1643 # if ask for an array, return ($stmt, @bind)
1644 # otherwise, s/?/shift @sqlv/ to put it inline
1646 return ($sql, @sqlv);
1648 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1649 ref $d ? $d->[1] : $d/e;
1658 # This allows us to check for a local, then _form, attr
1660 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1661 return $self->generate($name, @_);
1672 SQL::Abstract - Generate SQL from Perl data structures
1678 my $sql = SQL::Abstract->new;
1680 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1682 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1684 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1686 my($stmt, @bind) = $sql->delete($table, \%where);
1688 # Then, use these in your DBI statements
1689 my $sth = $dbh->prepare($stmt);
1690 $sth->execute(@bind);
1692 # Just generate the WHERE clause
1693 my($stmt, @bind) = $sql->where(\%where, $order);
1695 # Return values in the same order, for hashed queries
1696 # See PERFORMANCE section for more details
1697 my @bind = $sql->values(\%fieldvals);
1701 This module was inspired by the excellent L<DBIx::Abstract>.
1702 However, in using that module I found that what I really wanted
1703 to do was generate SQL, but still retain complete control over my
1704 statement handles and use the DBI interface. So, I set out to
1705 create an abstract SQL generation module.
1707 While based on the concepts used by L<DBIx::Abstract>, there are
1708 several important differences, especially when it comes to WHERE
1709 clauses. I have modified the concepts used to make the SQL easier
1710 to generate from Perl data structures and, IMO, more intuitive.
1711 The underlying idea is for this module to do what you mean, based
1712 on the data structures you provide it. The big advantage is that
1713 you don't have to modify your code every time your data changes,
1714 as this module figures it out.
1716 To begin with, an SQL INSERT is as easy as just specifying a hash
1717 of C<key=value> pairs:
1720 name => 'Jimbo Bobson',
1721 phone => '123-456-7890',
1722 address => '42 Sister Lane',
1723 city => 'St. Louis',
1724 state => 'Louisiana',
1727 The SQL can then be generated with this:
1729 my($stmt, @bind) = $sql->insert('people', \%data);
1731 Which would give you something like this:
1733 $stmt = "INSERT INTO people
1734 (address, city, name, phone, state)
1735 VALUES (?, ?, ?, ?, ?)";
1736 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1737 '123-456-7890', 'Louisiana');
1739 These are then used directly in your DBI code:
1741 my $sth = $dbh->prepare($stmt);
1742 $sth->execute(@bind);
1744 =head2 Inserting and Updating Arrays
1746 If your database has array types (like for example Postgres),
1747 activate the special option C<< array_datatypes => 1 >>
1748 when creating the C<SQL::Abstract> object.
1749 Then you may use an arrayref to insert and update database array types:
1751 my $sql = SQL::Abstract->new(array_datatypes => 1);
1753 planets => [qw/Mercury Venus Earth Mars/]
1756 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1760 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1762 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1765 =head2 Inserting and Updating SQL
1767 In order to apply SQL functions to elements of your C<%data> you may
1768 specify a reference to an arrayref for the given hash value. For example,
1769 if you need to execute the Oracle C<to_date> function on a value, you can
1770 say something like this:
1774 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1777 The first value in the array is the actual SQL. Any other values are
1778 optional and would be included in the bind values array. This gives
1781 my($stmt, @bind) = $sql->insert('people', \%data);
1783 $stmt = "INSERT INTO people (name, date_entered)
1784 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1785 @bind = ('Bill', '03/02/2003');
1787 An UPDATE is just as easy, all you change is the name of the function:
1789 my($stmt, @bind) = $sql->update('people', \%data);
1791 Notice that your C<%data> isn't touched; the module will generate
1792 the appropriately quirky SQL for you automatically. Usually you'll
1793 want to specify a WHERE clause for your UPDATE, though, which is
1794 where handling C<%where> hashes comes in handy...
1796 =head2 Complex where statements
1798 This module can generate pretty complicated WHERE statements
1799 easily. For example, simple C<key=value> pairs are taken to mean
1800 equality, and if you want to see if a field is within a set
1801 of values, you can use an arrayref. Let's say we wanted to
1802 SELECT some data based on this criteria:
1805 requestor => 'inna',
1806 worker => ['nwiger', 'rcwe', 'sfz'],
1807 status => { '!=', 'completed' }
1810 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1812 The above would give you something like this:
1814 $stmt = "SELECT * FROM tickets WHERE
1815 ( requestor = ? ) AND ( status != ? )
1816 AND ( worker = ? OR worker = ? OR worker = ? )";
1817 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1819 Which you could then use in DBI code like so:
1821 my $sth = $dbh->prepare($stmt);
1822 $sth->execute(@bind);
1828 The methods are simple. There's one for every major SQL operation,
1829 and a constructor you use first. The arguments are specified in a
1830 similar order for each method (table, then fields, then a where
1831 clause) to try and simplify things.
1833 =head2 new(option => 'value')
1835 The C<new()> function takes a list of options and values, and returns
1836 a new B<SQL::Abstract> object which can then be used to generate SQL
1837 through the methods below. The options accepted are:
1843 If set to 'lower', then SQL will be generated in all lowercase. By
1844 default SQL is generated in "textbook" case meaning something like:
1846 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1848 Any setting other than 'lower' is ignored.
1852 This determines what the default comparison operator is. By default
1853 it is C<=>, meaning that a hash like this:
1855 %where = (name => 'nwiger', email => 'nate@wiger.org');
1857 Will generate SQL like this:
1859 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1861 However, you may want loose comparisons by default, so if you set
1862 C<cmp> to C<like> you would get SQL such as:
1864 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1866 You can also override the comparison on an individual basis - see
1867 the huge section on L</"WHERE CLAUSES"> at the bottom.
1869 =item sqltrue, sqlfalse
1871 Expressions for inserting boolean values within SQL statements.
1872 By default these are C<1=1> and C<1=0>. They are used
1873 by the special operators C<-in> and C<-not_in> for generating
1874 correct SQL even when the argument is an empty array (see below).
1878 This determines the default logical operator for multiple WHERE
1879 statements in arrays or hashes. If absent, the default logic is "or"
1880 for arrays, and "and" for hashes. This means that a WHERE
1884 event_date => {'>=', '2/13/99'},
1885 event_date => {'<=', '4/24/03'},
1888 will generate SQL like this:
1890 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1892 This is probably not what you want given this query, though (look
1893 at the dates). To change the "OR" to an "AND", simply specify:
1895 my $sql = SQL::Abstract->new(logic => 'and');
1897 Which will change the above C<WHERE> to:
1899 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1901 The logic can also be changed locally by inserting
1902 a modifier in front of an arrayref :
1904 @where = (-and => [event_date => {'>=', '2/13/99'},
1905 event_date => {'<=', '4/24/03'} ]);
1907 See the L</"WHERE CLAUSES"> section for explanations.
1911 This will automatically convert comparisons using the specified SQL
1912 function for both column and value. This is mostly used with an argument
1913 of C<upper> or C<lower>, so that the SQL will have the effect of
1914 case-insensitive "searches". For example, this:
1916 $sql = SQL::Abstract->new(convert => 'upper');
1917 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1919 Will turn out the following SQL:
1921 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1923 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1924 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1925 not validate this option; it will just pass through what you specify verbatim).
1929 This is a kludge because many databases suck. For example, you can't
1930 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1931 Instead, you have to use C<bind_param()>:
1933 $sth->bind_param(1, 'reg data');
1934 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1936 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1937 which loses track of which field each slot refers to. Fear not.
1939 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1940 Currently, you can specify either C<normal> (default) or C<columns>. If you
1941 specify C<columns>, you will get an array that looks like this:
1943 my $sql = SQL::Abstract->new(bindtype => 'columns');
1944 my($stmt, @bind) = $sql->insert(...);
1947 [ 'column1', 'value1' ],
1948 [ 'column2', 'value2' ],
1949 [ 'column3', 'value3' ],
1952 You can then iterate through this manually, using DBI's C<bind_param()>.
1954 $sth->prepare($stmt);
1957 my($col, $data) = @$_;
1958 if ($col eq 'details' || $col eq 'comments') {
1959 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1960 } elsif ($col eq 'image') {
1961 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1963 $sth->bind_param($i, $data);
1967 $sth->execute; # execute without @bind now
1969 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1970 Basically, the advantage is still that you don't have to care which fields
1971 are or are not included. You could wrap that above C<for> loop in a simple
1972 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1973 get a layer of abstraction over manual SQL specification.
1975 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1976 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1977 will expect the bind values in this format.
1981 This is the character that a table or column name will be quoted
1982 with. By default this is an empty string, but you could set it to
1983 the character C<`>, to generate SQL like this:
1985 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1987 Alternatively, you can supply an array ref of two items, the first being the left
1988 hand quote character, and the second the right hand quote character. For
1989 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1990 that generates SQL like this:
1992 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1994 Quoting is useful if you have tables or columns names that are reserved
1995 words in your database's SQL dialect.
1999 This is the character that will be used to escape L</quote_char>s appearing
2000 in an identifier before it has been quoted.
2002 The parameter default in case of a single L</quote_char> character is the quote
2005 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
2006 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
2007 of the B<opening (left)> L</quote_char> within the identifier are currently left
2008 untouched. The default for opening-closing-style quotes may change in future
2009 versions, thus you are B<strongly encouraged> to specify the escape character
2014 This is the character that separates a table and column name. It is
2015 necessary to specify this when the C<quote_char> option is selected,
2016 so that tables and column names can be individually quoted like this:
2018 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
2020 =item injection_guard
2022 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
2023 column name specified in a query structure. This is a safety mechanism to avoid
2024 injection attacks when mishandling user input e.g.:
2026 my %condition_as_column_value_pairs = get_values_from_user();
2027 $sqla->select( ... , \%condition_as_column_value_pairs );
2029 If the expression matches an exception is thrown. Note that literal SQL
2030 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
2032 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
2034 =item array_datatypes
2036 When this option is true, arrayrefs in INSERT or UPDATE are
2037 interpreted as array datatypes and are passed directly
2039 When this option is false, arrayrefs are interpreted
2040 as literal SQL, just like refs to arrayrefs
2041 (but this behavior is for backwards compatibility; when writing
2042 new queries, use the "reference to arrayref" syntax
2048 Takes a reference to a list of "special operators"
2049 to extend the syntax understood by L<SQL::Abstract>.
2050 See section L</"SPECIAL OPERATORS"> for details.
2054 Takes a reference to a list of "unary operators"
2055 to extend the syntax understood by L<SQL::Abstract>.
2056 See section L</"UNARY OPERATORS"> for details.
2062 =head2 insert($table, \@values || \%fieldvals, \%options)
2064 This is the simplest function. You simply give it a table name
2065 and either an arrayref of values or hashref of field/value pairs.
2066 It returns an SQL INSERT statement and a list of bind values.
2067 See the sections on L</"Inserting and Updating Arrays"> and
2068 L</"Inserting and Updating SQL"> for information on how to insert
2069 with those data types.
2071 The optional C<\%options> hash reference may contain additional
2072 options to generate the insert SQL. Currently supported options
2079 Takes either a scalar of raw SQL fields, or an array reference of
2080 field names, and adds on an SQL C<RETURNING> statement at the end.
2081 This allows you to return data generated by the insert statement
2082 (such as row IDs) without performing another C<SELECT> statement.
2083 Note, however, this is not part of the SQL standard and may not
2084 be supported by all database engines.
2088 =head2 update($table, \%fieldvals, \%where, \%options)
2090 This takes a table, hashref of field/value pairs, and an optional
2091 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
2093 See the sections on L</"Inserting and Updating Arrays"> and
2094 L</"Inserting and Updating SQL"> for information on how to insert
2095 with those data types.
2097 The optional C<\%options> hash reference may contain additional
2098 options to generate the update SQL. Currently supported options
2105 See the C<returning> option to
2106 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2110 =head2 select($source, $fields, $where, $order)
2112 This returns a SQL SELECT statement and associated list of bind values, as
2113 specified by the arguments :
2119 Specification of the 'FROM' part of the statement.
2120 The argument can be either a plain scalar (interpreted as a table
2121 name, will be quoted), or an arrayref (interpreted as a list
2122 of table names, joined by commas, quoted), or a scalarref
2123 (literal table name, not quoted), or a ref to an arrayref
2124 (list of literal table names, joined by commas, not quoted).
2128 Specification of the list of fields to retrieve from
2130 The argument can be either an arrayref (interpreted as a list
2131 of field names, will be joined by commas and quoted), or a
2132 plain scalar (literal SQL, not quoted).
2133 Please observe that this API is not as flexible as that of
2134 the first argument C<$source>, for backwards compatibility reasons.
2138 Optional argument to specify the WHERE part of the query.
2139 The argument is most often a hashref, but can also be
2140 an arrayref or plain scalar --
2141 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2145 Optional argument to specify the ORDER BY part of the query.
2146 The argument can be a scalar, a hashref or an arrayref
2147 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2153 =head2 delete($table, \%where)
2155 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2156 It returns an SQL DELETE statement and list of bind values.
2158 =head2 where(\%where, $order)
2160 This is used to generate just the WHERE clause. For example,
2161 if you have an arbitrary data structure and know what the
2162 rest of your SQL is going to look like, but want an easy way
2163 to produce a WHERE clause, use this. It returns an SQL WHERE
2164 clause and list of bind values.
2167 =head2 values(\%data)
2169 This just returns the values from the hash C<%data>, in the same
2170 order that would be returned from any of the other above queries.
2171 Using this allows you to markedly speed up your queries if you
2172 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2174 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2176 Warning: This is an experimental method and subject to change.
2178 This returns arbitrarily generated SQL. It's a really basic shortcut.
2179 It will return two different things, depending on return context:
2181 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2182 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2184 These would return the following:
2186 # First calling form
2187 $stmt = "CREATE TABLE test (?, ?)";
2188 @bind = (field1, field2);
2190 # Second calling form
2191 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2193 Depending on what you're trying to do, it's up to you to choose the correct
2194 format. In this example, the second form is what you would want.
2198 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2202 ALTER SESSION SET nls_date_format = 'MM/YY'
2204 You get the idea. Strings get their case twiddled, but everything
2205 else remains verbatim.
2207 =head1 EXPORTABLE FUNCTIONS
2209 =head2 is_plain_value
2211 Determines if the supplied argument is a plain value as understood by this
2216 =item * The value is C<undef>
2218 =item * The value is a non-reference
2220 =item * The value is an object with stringification overloading
2222 =item * The value is of the form C<< { -value => $anything } >>
2226 On failure returns C<undef>, on sucess returns a B<scalar> reference
2227 to the original supplied argument.
2233 The stringification overloading detection is rather advanced: it takes
2234 into consideration not only the presence of a C<""> overload, but if that
2235 fails also checks for enabled
2236 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2237 on either C<0+> or C<bool>.
2239 Unfortunately testing in the field indicates that this
2240 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2241 but only when very large numbers of stringifying objects are involved.
2242 At the time of writing ( Sep 2014 ) there is no clear explanation of
2243 the direct cause, nor is there a manageably small test case that reliably
2244 reproduces the problem.
2246 If you encounter any of the following exceptions in B<random places within
2247 your application stack> - this module may be to blame:
2249 Operation "ne": no method found,
2250 left argument in overloaded package <something>,
2251 right argument in overloaded package <something>
2255 Stub found while resolving method "???" overloading """" in package <something>
2257 If you fall victim to the above - please attempt to reduce the problem
2258 to something that could be sent to the L<SQL::Abstract developers
2259 |DBIx::Class/GETTING HELP/SUPPORT>
2260 (either publicly or privately). As a workaround in the meantime you can
2261 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2262 value, which will most likely eliminate your problem (at the expense of
2263 not being able to properly detect exotic forms of stringification).
2265 This notice and environment variable will be removed in a future version,
2266 as soon as the underlying problem is found and a reliable workaround is
2271 =head2 is_literal_value
2273 Determines if the supplied argument is a literal value as understood by this
2278 =item * C<\$sql_string>
2280 =item * C<\[ $sql_string, @bind_values ]>
2284 On failure returns C<undef>, on sucess returns an B<array> reference
2285 containing the unpacked version of the supplied literal SQL and bind values.
2287 =head1 WHERE CLAUSES
2291 This module uses a variation on the idea from L<DBIx::Abstract>. It
2292 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2293 module is that things in arrays are OR'ed, and things in hashes
2296 The easiest way to explain is to show lots of examples. After
2297 each C<%where> hash shown, it is assumed you used:
2299 my($stmt, @bind) = $sql->where(\%where);
2301 However, note that the C<%where> hash can be used directly in any
2302 of the other functions as well, as described above.
2304 =head2 Key-value pairs
2306 So, let's get started. To begin, a simple hash:
2310 status => 'completed'
2313 Is converted to SQL C<key = val> statements:
2315 $stmt = "WHERE user = ? AND status = ?";
2316 @bind = ('nwiger', 'completed');
2318 One common thing I end up doing is having a list of values that
2319 a field can be in. To do this, simply specify a list inside of
2324 status => ['assigned', 'in-progress', 'pending'];
2327 This simple code will create the following:
2329 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2330 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2332 A field associated to an empty arrayref will be considered a
2333 logical false and will generate 0=1.
2335 =head2 Tests for NULL values
2337 If the value part is C<undef> then this is converted to SQL <IS NULL>
2346 $stmt = "WHERE user = ? AND status IS NULL";
2349 To test if a column IS NOT NULL:
2353 status => { '!=', undef },
2356 =head2 Specific comparison operators
2358 If you want to specify a different type of operator for your comparison,
2359 you can use a hashref for a given column:
2363 status => { '!=', 'completed' }
2366 Which would generate:
2368 $stmt = "WHERE user = ? AND status != ?";
2369 @bind = ('nwiger', 'completed');
2371 To test against multiple values, just enclose the values in an arrayref:
2373 status => { '=', ['assigned', 'in-progress', 'pending'] };
2375 Which would give you:
2377 "WHERE status = ? OR status = ? OR status = ?"
2380 The hashref can also contain multiple pairs, in which case it is expanded
2381 into an C<AND> of its elements:
2385 status => { '!=', 'completed', -not_like => 'pending%' }
2388 # Or more dynamically, like from a form
2389 $where{user} = 'nwiger';
2390 $where{status}{'!='} = 'completed';
2391 $where{status}{'-not_like'} = 'pending%';
2393 # Both generate this
2394 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2395 @bind = ('nwiger', 'completed', 'pending%');
2398 To get an OR instead, you can combine it with the arrayref idea:
2402 priority => [ { '=', 2 }, { '>', 5 } ]
2405 Which would generate:
2407 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2408 @bind = ('2', '5', 'nwiger');
2410 If you want to include literal SQL (with or without bind values), just use a
2411 scalar reference or reference to an arrayref as the value:
2414 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2415 date_expires => { '<' => \"now()" }
2418 Which would generate:
2420 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2421 @bind = ('11/26/2008');
2424 =head2 Logic and nesting operators
2426 In the example above,
2427 there is a subtle trap if you want to say something like
2428 this (notice the C<AND>):
2430 WHERE priority != ? AND priority != ?
2432 Because, in Perl you I<can't> do this:
2434 priority => { '!=' => 2, '!=' => 1 }
2436 As the second C<!=> key will obliterate the first. The solution
2437 is to use the special C<-modifier> form inside an arrayref:
2439 priority => [ -and => {'!=', 2},
2443 Normally, these would be joined by C<OR>, but the modifier tells it
2444 to use C<AND> instead. (Hint: You can use this in conjunction with the
2445 C<logic> option to C<new()> in order to change the way your queries
2446 work by default.) B<Important:> Note that the C<-modifier> goes
2447 B<INSIDE> the arrayref, as an extra first element. This will
2448 B<NOT> do what you think it might:
2450 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2452 Here is a quick list of equivalencies, since there is some overlap:
2455 status => {'!=', 'completed', 'not like', 'pending%' }
2456 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2459 status => {'=', ['assigned', 'in-progress']}
2460 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2461 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2465 =head2 Special operators : IN, BETWEEN, etc.
2467 You can also use the hashref format to compare a list of fields using the
2468 C<IN> comparison operator, by specifying the list as an arrayref:
2471 status => 'completed',
2472 reportid => { -in => [567, 2335, 2] }
2475 Which would generate:
2477 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2478 @bind = ('completed', '567', '2335', '2');
2480 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2483 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2484 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2485 'sqltrue' (by default : C<1=1>).
2487 In addition to the array you can supply a chunk of literal sql or
2488 literal sql with bind:
2491 customer => { -in => \[
2492 'SELECT cust_id FROM cust WHERE balance > ?',
2495 status => { -in => \'SELECT status_codes FROM states' },
2501 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2502 AND status IN ( SELECT status_codes FROM states )
2506 Finally, if the argument to C<-in> is not a reference, it will be
2507 treated as a single-element array.
2509 Another pair of operators is C<-between> and C<-not_between>,
2510 used with an arrayref of two values:
2514 completion_date => {
2515 -not_between => ['2002-10-01', '2003-02-06']
2521 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2523 Just like with C<-in> all plausible combinations of literal SQL
2527 start0 => { -between => [ 1, 2 ] },
2528 start1 => { -between => \["? AND ?", 1, 2] },
2529 start2 => { -between => \"lower(x) AND upper(y)" },
2530 start3 => { -between => [
2532 \["upper(?)", 'stuff' ],
2539 ( start0 BETWEEN ? AND ? )
2540 AND ( start1 BETWEEN ? AND ? )
2541 AND ( start2 BETWEEN lower(x) AND upper(y) )
2542 AND ( start3 BETWEEN lower(x) AND upper(?) )
2544 @bind = (1, 2, 1, 2, 'stuff');
2547 These are the two builtin "special operators"; but the
2548 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2550 =head2 Unary operators: bool
2552 If you wish to test against boolean columns or functions within your
2553 database you can use the C<-bool> and C<-not_bool> operators. For
2554 example to test the column C<is_user> being true and the column
2555 C<is_enabled> being false you would use:-
2559 -not_bool => 'is_enabled',
2564 WHERE is_user AND NOT is_enabled
2566 If a more complex combination is required, testing more conditions,
2567 then you should use the and/or operators:-
2572 -not_bool => { two=> { -rlike => 'bar' } },
2573 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2584 (NOT ( three = ? OR three > ? ))
2587 =head2 Nested conditions, -and/-or prefixes
2589 So far, we've seen how multiple conditions are joined with a top-level
2590 C<AND>. We can change this by putting the different conditions we want in
2591 hashes and then putting those hashes in an array. For example:
2596 status => { -like => ['pending%', 'dispatched'] },
2600 status => 'unassigned',
2604 This data structure would create the following:
2606 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2607 OR ( user = ? AND status = ? ) )";
2608 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2611 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2612 to change the logic inside :
2618 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2619 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2626 $stmt = "WHERE ( user = ?
2627 AND ( ( workhrs > ? AND geo = ? )
2628 OR ( workhrs < ? OR geo = ? ) ) )";
2629 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2631 =head3 Algebraic inconsistency, for historical reasons
2633 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2634 operator goes C<outside> of the nested structure; whereas when connecting
2635 several constraints on one column, the C<-and> operator goes
2636 C<inside> the arrayref. Here is an example combining both features :
2639 -and => [a => 1, b => 2],
2640 -or => [c => 3, d => 4],
2641 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2646 WHERE ( ( ( a = ? AND b = ? )
2647 OR ( c = ? OR d = ? )
2648 OR ( e LIKE ? AND e LIKE ? ) ) )
2650 This difference in syntax is unfortunate but must be preserved for
2651 historical reasons. So be careful : the two examples below would
2652 seem algebraically equivalent, but they are not
2655 { -like => 'foo%' },
2656 { -like => '%bar' },
2658 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2661 { col => { -like => 'foo%' } },
2662 { col => { -like => '%bar' } },
2664 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2667 =head2 Literal SQL and value type operators
2669 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2670 side" is a column name and the "right side" is a value (normally rendered as
2671 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2672 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2673 alter this behavior. There are several ways of doing so.
2677 This is a virtual operator that signals the string to its right side is an
2678 identifier (a column name) and not a value. For example to compare two
2679 columns you would write:
2682 priority => { '<', 2 },
2683 requestor => { -ident => 'submitter' },
2688 $stmt = "WHERE priority < ? AND requestor = submitter";
2691 If you are maintaining legacy code you may see a different construct as
2692 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2697 This is a virtual operator that signals that the construct to its right side
2698 is a value to be passed to DBI. This is for example necessary when you want
2699 to write a where clause against an array (for RDBMS that support such
2700 datatypes). For example:
2703 array => { -value => [1, 2, 3] }
2708 $stmt = 'WHERE array = ?';
2709 @bind = ([1, 2, 3]);
2711 Note that if you were to simply say:
2717 the result would probably not be what you wanted:
2719 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2724 Finally, sometimes only literal SQL will do. To include a random snippet
2725 of SQL verbatim, you specify it as a scalar reference. Consider this only
2726 as a last resort. Usually there is a better way. For example:
2729 priority => { '<', 2 },
2730 requestor => { -in => \'(SELECT name FROM hitmen)' },
2735 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2738 Note that in this example, you only get one bind parameter back, since
2739 the verbatim SQL is passed as part of the statement.
2743 Never use untrusted input as a literal SQL argument - this is a massive
2744 security risk (there is no way to check literal snippets for SQL
2745 injections and other nastyness). If you need to deal with untrusted input
2746 use literal SQL with placeholders as described next.
2748 =head3 Literal SQL with placeholders and bind values (subqueries)
2750 If the literal SQL to be inserted has placeholders and bind values,
2751 use a reference to an arrayref (yes this is a double reference --
2752 not so common, but perfectly legal Perl). For example, to find a date
2753 in Postgres you can use something like this:
2756 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2761 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2764 Note that you must pass the bind values in the same format as they are returned
2765 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2766 to C<columns>, you must provide the bind values in the
2767 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2768 scalar value; most commonly the column name, but you can use any scalar value
2769 (including references and blessed references), L<SQL::Abstract> will simply
2770 pass it through intact. So if C<bindtype> is set to C<columns> the above
2771 example will look like:
2774 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2777 Literal SQL is especially useful for nesting parenthesized clauses in the
2778 main SQL query. Here is a first example :
2780 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2784 bar => \["IN ($sub_stmt)" => @sub_bind],
2789 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2790 WHERE c2 < ? AND c3 LIKE ?))";
2791 @bind = (1234, 100, "foo%");
2793 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2794 are expressed in the same way. Of course the C<$sub_stmt> and
2795 its associated bind values can be generated through a former call
2798 my ($sub_stmt, @sub_bind)
2799 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2800 c3 => {-like => "foo%"}});
2803 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2806 In the examples above, the subquery was used as an operator on a column;
2807 but the same principle also applies for a clause within the main C<%where>
2808 hash, like an EXISTS subquery :
2810 my ($sub_stmt, @sub_bind)
2811 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2812 my %where = ( -and => [
2814 \["EXISTS ($sub_stmt)" => @sub_bind],
2819 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2820 WHERE c1 = ? AND c2 > t0.c0))";
2824 Observe that the condition on C<c2> in the subquery refers to
2825 column C<t0.c0> of the main query : this is I<not> a bind
2826 value, so we have to express it through a scalar ref.
2827 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2828 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2829 what we wanted here.
2831 Finally, here is an example where a subquery is used
2832 for expressing unary negation:
2834 my ($sub_stmt, @sub_bind)
2835 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2836 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2838 lname => {like => '%son%'},
2839 \["NOT ($sub_stmt)" => @sub_bind],
2844 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2845 @bind = ('%son%', 10, 20)
2847 =head3 Deprecated usage of Literal SQL
2849 Below are some examples of archaic use of literal SQL. It is shown only as
2850 reference for those who deal with legacy code. Each example has a much
2851 better, cleaner and safer alternative that users should opt for in new code.
2857 my %where = ( requestor => \'IS NOT NULL' )
2859 $stmt = "WHERE requestor IS NOT NULL"
2861 This used to be the way of generating NULL comparisons, before the handling
2862 of C<undef> got formalized. For new code please use the superior syntax as
2863 described in L</Tests for NULL values>.
2867 my %where = ( requestor => \'= submitter' )
2869 $stmt = "WHERE requestor = submitter"
2871 This used to be the only way to compare columns. Use the superior L</-ident>
2872 method for all new code. For example an identifier declared in such a way
2873 will be properly quoted if L</quote_char> is properly set, while the legacy
2874 form will remain as supplied.
2878 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2880 $stmt = "WHERE completed > ? AND is_ready"
2881 @bind = ('2012-12-21')
2883 Using an empty string literal used to be the only way to express a boolean.
2884 For all new code please use the much more readable
2885 L<-bool|/Unary operators: bool> operator.
2891 These pages could go on for a while, since the nesting of the data
2892 structures this module can handle are pretty much unlimited (the
2893 module implements the C<WHERE> expansion as a recursive function
2894 internally). Your best bet is to "play around" with the module a
2895 little to see how the data structures behave, and choose the best
2896 format for your data based on that.
2898 And of course, all the values above will probably be replaced with
2899 variables gotten from forms or the command line. After all, if you
2900 knew everything ahead of time, you wouldn't have to worry about
2901 dynamically-generating SQL and could just hardwire it into your
2904 =head1 ORDER BY CLAUSES
2906 Some functions take an order by clause. This can either be a scalar (just a
2907 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2908 or an array of either of the two previous forms. Examples:
2910 Given | Will Generate
2911 ----------------------------------------------------------
2913 \'colA DESC' | ORDER BY colA DESC
2915 'colA' | ORDER BY colA
2917 [qw/colA colB/] | ORDER BY colA, colB
2919 {-asc => 'colA'} | ORDER BY colA ASC
2921 {-desc => 'colB'} | ORDER BY colB DESC
2923 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2925 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2928 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2929 { -desc => [qw/colB/], | colC ASC, colD ASC
2930 { -asc => [qw/colC colD/],|
2932 ===========================================================
2936 =head1 SPECIAL OPERATORS
2938 my $sqlmaker = SQL::Abstract->new(special_ops => [
2942 my ($self, $field, $op, $arg) = @_;
2948 handler => 'method_name',
2952 A "special operator" is a SQL syntactic clause that can be
2953 applied to a field, instead of a usual binary operator.
2956 WHERE field IN (?, ?, ?)
2957 WHERE field BETWEEN ? AND ?
2958 WHERE MATCH(field) AGAINST (?, ?)
2960 Special operators IN and BETWEEN are fairly standard and therefore
2961 are builtin within C<SQL::Abstract> (as the overridable methods
2962 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2963 like the MATCH .. AGAINST example above which is specific to MySQL,
2964 you can write your own operator handlers - supply a C<special_ops>
2965 argument to the C<new> method. That argument takes an arrayref of
2966 operator definitions; each operator definition is a hashref with two
2973 the regular expression to match the operator
2977 Either a coderef or a plain scalar method name. In both cases
2978 the expected return is C<< ($sql, @bind) >>.
2980 When supplied with a method name, it is simply called on the
2981 L<SQL::Abstract> object as:
2983 $self->$method_name ($field, $op, $arg)
2987 $field is the LHS of the operator
2988 $op is the part that matched the handler regex
2991 When supplied with a coderef, it is called as:
2993 $coderef->($self, $field, $op, $arg)
2998 For example, here is an implementation
2999 of the MATCH .. AGAINST syntax for MySQL
3001 my $sqlmaker = SQL::Abstract->new(special_ops => [
3003 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
3004 {regex => qr/^match$/i,
3006 my ($self, $field, $op, $arg) = @_;
3007 $arg = [$arg] if not ref $arg;
3008 my $label = $self->_quote($field);
3009 my ($placeholder) = $self->_convert('?');
3010 my $placeholders = join ", ", (($placeholder) x @$arg);
3011 my $sql = $self->_sqlcase('match') . " ($label) "
3012 . $self->_sqlcase('against') . " ($placeholders) ";
3013 my @bind = $self->_bindtype($field, @$arg);
3014 return ($sql, @bind);
3021 =head1 UNARY OPERATORS
3023 my $sqlmaker = SQL::Abstract->new(unary_ops => [
3027 my ($self, $op, $arg) = @_;
3033 handler => 'method_name',
3037 A "unary operator" is a SQL syntactic clause that can be
3038 applied to a field - the operator goes before the field
3040 You can write your own operator handlers - supply a C<unary_ops>
3041 argument to the C<new> method. That argument takes an arrayref of
3042 operator definitions; each operator definition is a hashref with two
3049 the regular expression to match the operator
3053 Either a coderef or a plain scalar method name. In both cases
3054 the expected return is C<< $sql >>.
3056 When supplied with a method name, it is simply called on the
3057 L<SQL::Abstract> object as:
3059 $self->$method_name ($op, $arg)
3063 $op is the part that matched the handler regex
3064 $arg is the RHS or argument of the operator
3066 When supplied with a coderef, it is called as:
3068 $coderef->($self, $op, $arg)
3076 Thanks to some benchmarking by Mark Stosberg, it turns out that
3077 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
3078 I must admit this wasn't an intentional design issue, but it's a
3079 byproduct of the fact that you get to control your C<DBI> handles
3082 To maximize performance, use a code snippet like the following:
3084 # prepare a statement handle using the first row
3085 # and then reuse it for the rest of the rows
3087 for my $href (@array_of_hashrefs) {
3088 $stmt ||= $sql->insert('table', $href);
3089 $sth ||= $dbh->prepare($stmt);
3090 $sth->execute($sql->values($href));
3093 The reason this works is because the keys in your C<$href> are sorted
3094 internally by B<SQL::Abstract>. Thus, as long as your data retains
3095 the same structure, you only have to generate the SQL the first time
3096 around. On subsequent queries, simply use the C<values> function provided
3097 by this module to return your values in the correct order.
3099 However this depends on the values having the same type - if, for
3100 example, the values of a where clause may either have values
3101 (resulting in sql of the form C<column = ?> with a single bind
3102 value), or alternatively the values might be C<undef> (resulting in
3103 sql of the form C<column IS NULL> with no bind value) then the
3104 caching technique suggested will not work.
3108 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3109 really like this part (I do, at least). Building up a complex query
3110 can be as simple as the following:
3117 use CGI::FormBuilder;
3120 my $form = CGI::FormBuilder->new(...);
3121 my $sql = SQL::Abstract->new;
3123 if ($form->submitted) {
3124 my $field = $form->field;
3125 my $id = delete $field->{id};
3126 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3129 Of course, you would still have to connect using C<DBI> to run the
3130 query, but the point is that if you make your form look like your
3131 table, the actual query script can be extremely simplistic.
3133 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3134 a fast interface to returning and formatting data. I frequently
3135 use these three modules together to write complex database query
3136 apps in under 50 lines.
3138 =head1 HOW TO CONTRIBUTE
3140 Contributions are always welcome, in all usable forms (we especially
3141 welcome documentation improvements). The delivery methods include git-
3142 or unified-diff formatted patches, GitHub pull requests, or plain bug
3143 reports either via RT or the Mailing list. Contributors are generally
3144 granted full access to the official repository after their first several
3145 patches pass successful review.
3147 This project is maintained in a git repository. The code and related tools are
3148 accessible at the following locations:
3152 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3154 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3156 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3158 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3164 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3165 Great care has been taken to preserve the I<published> behavior
3166 documented in previous versions in the 1.* family; however,
3167 some features that were previously undocumented, or behaved
3168 differently from the documentation, had to be changed in order
3169 to clarify the semantics. Hence, client code that was relying
3170 on some dark areas of C<SQL::Abstract> v1.*
3171 B<might behave differently> in v1.50.
3173 The main changes are :
3179 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3183 support for the { operator => \"..." } construct (to embed literal SQL)
3187 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3191 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3195 defensive programming : check arguments
3199 fixed bug with global logic, which was previously implemented
3200 through global variables yielding side-effects. Prior versions would
3201 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3202 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3203 Now this is interpreted
3204 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3209 fixed semantics of _bindtype on array args
3213 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3214 we just avoid shifting arrays within that tree.
3218 dropped the C<_modlogic> function
3222 =head1 ACKNOWLEDGEMENTS
3224 There are a number of individuals that have really helped out with
3225 this module. Unfortunately, most of them submitted bugs via CPAN
3226 so I have no idea who they are! But the people I do know are:
3228 Ash Berlin (order_by hash term support)
3229 Matt Trout (DBIx::Class support)
3230 Mark Stosberg (benchmarking)
3231 Chas Owens (initial "IN" operator support)
3232 Philip Collins (per-field SQL functions)
3233 Eric Kolve (hashref "AND" support)
3234 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3235 Dan Kubb (support for "quote_char" and "name_sep")
3236 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3237 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3238 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3239 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3240 Oliver Charles (support for "RETURNING" after "INSERT")
3246 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3250 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3252 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3254 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3255 While not an official support venue, C<DBIx::Class> makes heavy use of
3256 C<SQL::Abstract>, and as such list members there are very familiar with
3257 how to create queries.
3261 This module is free software; you may copy this under the same
3262 terms as perl itself (either the GNU General Public License or
3263 the Artistic License)