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 = '1.87';
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 => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
187 $opt{expand_unary} = {};
190 -not => '_expand_not',
191 -bool => '_expand_bool',
192 -and => '_expand_op_andor',
193 -or => '_expand_op_andor',
194 -nest => '_expand_nest',
198 'between' => '_expand_between',
199 'not between' => '_expand_between',
200 'in' => '_expand_in',
201 'not in' => '_expand_in',
202 'nest' => '_expand_nest',
203 (map +($_ => '_expand_op_andor'),
207 # placeholder for _expand_unop system
209 my %unops = (-ident => '_expand_ident', -value => '_expand_value');
210 foreach my $name (keys %unops) {
211 $opt{expand}{$name} = $unops{$name};
212 my ($op) = $name =~ /^-(.*)$/;
213 $opt{expand_op}{$op} = sub {
214 my ($self, $op, $arg, $k) = @_;
217 $self->_expand_ident(-ident => $k),
218 $self->_expand_expr({ '-'.$op => $arg }),
225 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
229 $opt{render_op} = our $RENDER_OP;
231 return bless \%opt, $class;
234 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
235 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
237 sub _assert_pass_injection_guard {
238 if ($_[1] =~ $_[0]->{injection_guard}) {
239 my $class = ref $_[0];
240 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
241 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
242 . "{injection_guard} attribute to ${class}->new()"
247 #======================================================================
249 #======================================================================
253 my $table = $self->_table(shift);
254 my $data = shift || return;
257 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
258 my ($sql, @bind) = $self->$method($data);
259 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
261 if ($options->{returning}) {
262 my ($s, @b) = $self->_insert_returning($options);
267 return wantarray ? ($sql, @bind) : $sql;
270 # So that subclasses can override INSERT ... RETURNING separately from
271 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
272 sub _insert_returning { shift->_returning(@_) }
275 my ($self, $options) = @_;
277 my $f = $options->{returning};
279 my ($sql, @bind) = $self->render_aqt(
280 $self->_expand_maybe_list_expr($f, undef, -ident)
283 ? $self->_sqlcase(' returning ') . $sql
284 : ($self->_sqlcase(' returning ').$sql, @bind);
287 sub _insert_HASHREF { # explicit list of fields and then values
288 my ($self, $data) = @_;
290 my @fields = sort keys %$data;
292 my ($sql, @bind) = $self->_insert_values($data);
295 $_ = $self->_quote($_) foreach @fields;
296 $sql = "( ".join(", ", @fields).") ".$sql;
298 return ($sql, @bind);
301 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
302 my ($self, $data) = @_;
304 # no names (arrayref) so can't generate bindtype
305 $self->{bindtype} ne 'columns'
306 or belch "can't do 'columns' bindtype when called with arrayref";
308 my (@values, @all_bind);
309 foreach my $value (@$data) {
310 my ($values, @bind) = $self->_insert_value(undef, $value);
311 push @values, $values;
312 push @all_bind, @bind;
314 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
315 return ($sql, @all_bind);
318 sub _insert_ARRAYREFREF { # literal SQL with bind
319 my ($self, $data) = @_;
321 my ($sql, @bind) = @${$data};
322 $self->_assert_bindval_matches_bindtype(@bind);
324 return ($sql, @bind);
328 sub _insert_SCALARREF { # literal SQL without bind
329 my ($self, $data) = @_;
335 my ($self, $data) = @_;
337 my (@values, @all_bind);
338 foreach my $column (sort keys %$data) {
339 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
340 push @values, $values;
341 push @all_bind, @bind;
343 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
344 return ($sql, @all_bind);
348 my ($self, $column, $v) = @_;
350 return $self->render_aqt(
351 $self->_expand_insert_value($column, $v)
355 sub _expand_insert_value {
356 my ($self, $column, $v) = @_;
358 if (ref($v) eq 'ARRAY') {
359 if ($self->{array_datatypes}) {
360 return +{ -bind => [ $column, $v ] };
362 my ($sql, @bind) = @$v;
363 $self->_assert_bindval_matches_bindtype(@bind);
364 return +{ -literal => $v };
366 if (ref($v) eq 'HASH') {
367 if (grep !/^-/, keys %$v) {
368 belch "HASH ref as bind value in insert is not supported";
369 return +{ -bind => [ $column, $v ] };
373 return +{ -bind => [ $column, undef ] };
375 local our $Cur_Col_Meta = $column;
376 return $self->expand_expr($v);
381 #======================================================================
383 #======================================================================
388 my $table = $self->_table(shift);
389 my $data = shift || return;
393 # first build the 'SET' part of the sql statement
394 puke "Unsupported data type specified to \$sql->update"
395 unless ref $data eq 'HASH';
397 my ($sql, @all_bind) = $self->_update_set_values($data);
398 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
402 my($where_sql, @where_bind) = $self->where($where);
404 push @all_bind, @where_bind;
407 if ($options->{returning}) {
408 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
409 $sql .= $returning_sql;
410 push @all_bind, @returning_bind;
413 return wantarray ? ($sql, @all_bind) : $sql;
416 sub _update_set_values {
417 my ($self, $data) = @_;
419 return $self->render_aqt(
420 $self->_expand_update_set_values($data),
424 sub _expand_update_set_values {
425 my ($self, $data) = @_;
426 $self->_expand_maybe_list_expr( [
429 $set = { -bind => $_ } unless defined $set;
430 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
436 ? ($self->{array_datatypes}
437 ? [ $k, +{ -bind => [ $k, $v ] } ]
438 : [ $k, +{ -literal => $v } ])
440 local our $Cur_Col_Meta = $k;
441 [ $k, $self->_expand_expr($v) ]
448 # So that subclasses can override UPDATE ... RETURNING separately from
450 sub _update_returning { shift->_returning(@_) }
454 #======================================================================
456 #======================================================================
461 my $table = $self->_table(shift);
462 my $fields = shift || '*';
466 my ($fields_sql, @bind) = $self->_select_fields($fields);
468 my ($where_sql, @where_bind) = $self->where($where, $order);
469 push @bind, @where_bind;
471 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
472 $self->_sqlcase('from'), $table)
475 return wantarray ? ($sql, @bind) : $sql;
479 my ($self, $fields) = @_;
480 return $fields unless ref($fields);
481 return $self->render_aqt(
482 $self->_expand_maybe_list_expr($fields, undef, '-ident')
486 #======================================================================
488 #======================================================================
493 my $table = $self->_table(shift);
497 my($where_sql, @bind) = $self->where($where);
498 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
500 if ($options->{returning}) {
501 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
502 $sql .= $returning_sql;
503 push @bind, @returning_bind;
506 return wantarray ? ($sql, @bind) : $sql;
509 # So that subclasses can override DELETE ... RETURNING separately from
511 sub _delete_returning { shift->_returning(@_) }
515 #======================================================================
517 #======================================================================
521 # Finally, a separate routine just to handle WHERE clauses
523 my ($self, $where, $order) = @_;
525 local $self->{convert_where} = $self->{convert};
528 my ($sql, @bind) = defined($where)
529 ? $self->_recurse_where($where)
531 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
535 my ($order_sql, @order_bind) = $self->_order_by($order);
537 push @bind, @order_bind;
540 return wantarray ? ($sql, @bind) : $sql;
544 my ($self, $expr, $default_scalar_to) = @_;
545 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
546 $self->_expand_expr($expr);
550 my ($self, $aqt) = @_;
551 my ($k, $v, @rest) = %$aqt;
553 if (my $meth = $self->{render}{$k}) {
554 return $self->$meth($v);
556 die "notreached: $k";
560 my ($self, $expr) = @_;
561 $self->render_aqt($self->expand_expr($expr));
565 my ($self, $expr) = @_;
566 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
567 return undef unless defined($expr);
568 if (ref($expr) eq 'HASH') {
569 return undef unless my $kc = keys %$expr;
571 return $self->_expand_op_andor(-and => $expr);
573 my ($key, $value) = %$expr;
574 if ($key =~ /^-/ and $key =~ s/ [_\s]? \d+ $//x ) {
575 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
576 . "You probably wanted ...-and => [ $key => COND1, $key => COND2 ... ]";
578 if (my $exp = $self->{expand}{$key}) {
579 return $self->$exp($key, $value);
581 return $self->_expand_expr_hashpair($key, $value);
583 if (ref($expr) eq 'ARRAY') {
584 my $logic = '-'.lc($self->{logic});
585 return $self->_expand_op_andor($logic, $expr);
587 if (my $literal = is_literal_value($expr)) {
588 return +{ -literal => $literal };
590 if (!ref($expr) or Scalar::Util::blessed($expr)) {
591 if (my $d = our $Default_Scalar_To) {
592 return $self->_expand_expr({ $d => $expr });
594 return $self->_expand_value(-value => $expr);
599 sub _expand_expr_hashpair {
600 my ($self, $k, $v) = @_;
601 unless (defined($k) and length($k)) {
602 if (defined($k) and my $literal = is_literal_value($v)) {
603 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
604 return { -literal => $literal };
606 puke "Supplying an empty left hand side argument is not supported";
609 return $self->_expand_expr_hashpair_op($k, $v);
611 return $self->_expand_expr_hashpair_ident($k, $v);
614 sub _expand_expr_hashpair_ident {
615 my ($self, $k, $v) = @_;
620 and exists $v->{-value}
621 and not defined $v->{-value}
624 return $self->_expand_expr({ $k => { $self->{cmp} => undef } });
626 my $ik = $self->_expand_ident(-ident => $k);
627 if (!ref($v) or Scalar::Util::blessed($v)) {
628 my $d = our $Default_Scalar_To;
629 local our $Cur_Col_Meta = $k;
630 return $self->_expand_expr_hashpair_ident(
633 ? $self->_expand_expr($d => $v)
638 if (ref($v) eq 'HASH') {
640 return $self->_expand_op_andor(-and => [
641 map +{ $k => { $_ => $v->{$_} } },
645 return undef unless keys %$v;
647 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
648 $self->_assert_pass_injection_guard($op);
649 if ($op =~ s/ [_\s]? \d+ $//x ) {
650 return $self->_expand_expr($k, $v);
652 if (my $x = $self->{expand_op}{$op}) {
653 local our $Cur_Col_Meta = $k;
654 return $self->$x($op, $vv, $k);
656 if ($op =~ /^is(?: not)?$/) {
657 puke "$op can only take undef as argument"
661 and exists($vv->{-value})
662 and !defined($vv->{-value})
664 return +{ -op => [ $op.' null', $ik ] };
666 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
667 return { -op => [ $op, $ik, $vv ] };
669 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
673 { -op => [ $op, $vv ] }
676 if (ref($vv) eq 'ARRAY') {
677 my ($logic, @values) = (
678 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
683 $op =~ $self->{inequality_op}
684 or $op =~ $self->{not_like_op}
686 if (lc($logic) eq '-or' and @values > 1) {
687 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
688 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
689 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
694 # try to DWIM on equality operators
696 $op =~ $self->{equality_op} ? $self->sqlfalse
697 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
698 : $op =~ $self->{inequality_op} ? $self->sqltrue
699 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
700 : puke "operator '$op' applied on an empty array (field '$k')";
702 return $self->_expand_op_andor($logic => [
711 and exists $vv->{-value}
712 and not defined $vv->{-value}
716 $op =~ /^not$/i ? 'is not' # legacy
717 : $op =~ $self->{equality_op} ? 'is'
718 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
719 : $op =~ $self->{inequality_op} ? 'is not'
720 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
721 : puke "unexpected operator '$op' with undef operand";
722 return +{ -op => [ $is.' null', $ik ] };
724 local our $Cur_Col_Meta = $k;
728 $self->_expand_expr($vv)
731 if (ref($v) eq 'ARRAY') {
732 return $self->sqlfalse unless @$v;
733 $self->_debug("ARRAY($k) means distribute over elements");
735 $v->[0] =~ /^-(and|or)$/i
736 ? shift(@{$v = [ @$v ]})
737 : '-'.lc($self->{logic} || 'OR')
739 return $self->_expand_op_andor(
740 $logic => [ map +{ $k => $_ }, @$v ]
743 if (my $literal = is_literal_value($v)) {
745 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
748 my ($sql, @bind) = @$literal;
749 if ($self->{bindtype} eq 'columns') {
751 $self->_assert_bindval_matches_bindtype($_);
754 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
759 sub _expand_expr_hashpair_op {
760 my ($self, $k, $v) = @_;
762 $op =~ s/^-// if length($op) > 1;
763 $self->_assert_pass_injection_guard($op);
764 if (my ($rest) = $op =~/^not[_ ](.*)$/) {
767 $self->_expand_expr({ "-${rest}", $v })
770 # top level special ops are illegal in general
771 # note that, arguably, if it makes no sense at top level, it also
772 # makes no sense on the other side of an = sign or similar but DBIC
773 # gets disappointingly upset if I disallow it
775 (our $Expand_Depth) == 1
776 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
778 puke "Illegal use of top-level '-$op'"
780 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
781 return { -op => [ $op, $v ] };
783 if ($self->{render}{$k}) {
789 and (keys %$v)[0] =~ /^-/
791 my ($func) = $k =~ /^-(.*)$/;
792 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
793 return +{ -op => [ $func, $self->_expand_expr($v) ] };
795 return +{ -func => [ $func, $self->_expand_expr($v) ] };
797 if (!ref($v) or is_literal_value($v)) {
798 return +{ -op => [ $op, $self->_expand_expr($v) ] };
804 my ($self, $op, $body) = @_;
805 unless (defined($body) or (ref($body) and ref($body) eq 'ARRAY')) {
806 puke "$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
808 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
809 ref($body) ? @$body : $body;
810 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
811 unless ($self->{quote_char}) {
812 $self->_assert_pass_injection_guard($_) for @parts;
814 return +{ -ident => \@parts };
818 +{ -bind => [ our $Cur_Col_Meta, $_[2] ] };
822 +{ -op => [ 'not', $_[0]->_expand_expr($_[2]) ] };
826 my ($self, undef, $v) = @_;
828 return $self->_expand_expr($v);
830 puke "-bool => undef not supported" unless defined($v);
831 return $self->_expand_ident(-ident => $v);
834 sub _expand_op_andor {
835 my ($self, $logic, $v, $k) = @_;
837 $v = [ map +{ $k, $_ },
839 ? (map +{ $_ => $v->{$_} }, sort keys %$v)
843 my ($logop) = $logic =~ /^-?(.*)$/;
844 if (ref($v) eq 'HASH') {
847 map $self->_expand_expr({ $_ => $v->{$_} }),
851 if (ref($v) eq 'ARRAY') {
852 $logop eq 'and' or $logop eq 'or' or puke "unknown logic: $logop";
855 (ref($_) eq 'ARRAY' and @$_)
856 or (ref($_) eq 'HASH' and %$_)
862 while (my ($el) = splice @expr, 0, 1) {
863 puke "Supplying an empty left hand side argument is not supported in array-pairs"
864 unless defined($el) and length($el);
865 my $elref = ref($el);
867 local our $Expand_Depth = 0;
868 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
869 } elsif ($elref eq 'ARRAY') {
870 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
871 } elsif (my $l = is_literal_value($el)) {
872 push @res, { -literal => $l };
873 } elsif ($elref eq 'HASH') {
874 local our $Expand_Depth = 0;
875 push @res, grep defined, $self->_expand_expr($el) if %$el;
881 # return $res[0] if @res == 1;
882 return { -op => [ $logop, @res ] };
887 sub _expand_between {
888 my ($self, $op, $vv, $k) = @_;
889 local our $Cur_Col_Meta = $k;
890 my @rhs = map $self->_expand_expr($_),
891 ref($vv) eq 'ARRAY' ? @$vv : $vv;
893 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
895 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
897 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
901 $self->_expand_ident(-ident => $k),
907 my ($self, $op, $vv, $k) = @_;
908 if (my $literal = is_literal_value($vv)) {
909 my ($sql, @bind) = @$literal;
910 my $opened_sql = $self->_open_outer_paren($sql);
912 $op, $self->_expand_ident(-ident => $k),
913 [ { -literal => [ $opened_sql, @bind ] } ]
917 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
918 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
919 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
920 . 'will emit the logically correct SQL instead of raising this exception)'
922 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
924 my @rhs = map $self->_expand_expr($_),
925 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
926 map { defined($_) ? $_: puke($undef_err) }
927 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
928 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
932 $self->_expand_ident(-ident => $k),
938 my ($self, $op, $v) = @_;
939 # DBIx::Class requires a nest warning to be emitted once but the private
940 # method it overrode to do so no longer exists
941 if ($self->{is_dbic_sqlmaker}) {
942 unless (our $Nest_Warned) {
944 "-nest in search conditions is deprecated, you most probably wanted:\n"
945 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
950 return $self->_expand_expr($v);
954 my ($self, $where, $logic) = @_;
956 # Special case: top level simple string treated as literal
958 my $where_exp = (ref($where)
959 ? $self->_expand_expr($where, $logic)
960 : { -literal => [ $where ] });
962 # dispatch expanded expression
964 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
965 # DBIx::Class used to call _recurse_where in scalar context
966 # something else might too...
968 return ($sql, @bind);
971 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
977 my ($self, $ident) = @_;
979 return $self->_convert($self->_quote($ident));
983 my ($self, $list) = @_;
984 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
985 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
989 my ($self, $rest) = @_;
990 my ($func, @args) = @$rest;
994 push @arg_sql, shift @x;
996 } map [ $self->render_aqt($_) ], @args;
997 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1001 my ($self, $bind) = @_;
1002 return ($self->_convert('?'), $self->_bindtype(@$bind));
1005 sub _render_literal {
1006 my ($self, $literal) = @_;
1007 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1013 my ($self, $op, $args) = @_;
1014 my ($left, $low, $high) = @$args;
1015 my ($rhsql, @rhbind) = do {
1017 puke "Single arg to between must be a literal"
1018 unless $low->{-literal};
1021 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
1022 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
1023 @{$l}[1..$#$l], @{$h}[1..$#$h])
1026 my ($lhsql, @lhbind) = $self->render_aqt($left);
1028 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
1031 }), 'between', 'not between'),
1033 my ($self, $op, $args) = @_;
1034 my ($lhs, $rhs) = @$args;
1037 my ($sql, @bind) = $self->render_aqt($_);
1038 push @in_bind, @bind;
1041 my ($lhsql, @lbind) = $self->render_aqt($lhs);
1043 $lhsql.' '.$self->_sqlcase($op).' ( '
1044 .join(', ', @in_sql)
1048 }), 'in', 'not in'),
1049 (map +($_ => '_render_unop_postfix'),
1050 'is null', 'is not null', 'asc', 'desc',
1052 (not => '_render_op_not'),
1054 my ($self, $op, $args) = @_;
1055 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$args;
1056 return '' unless @parts;
1057 return @{$parts[0]} if @parts == 1;
1058 my ($final_sql) = join(
1059 ' '.$self->_sqlcase($op).' ',
1064 map @{$_}[1..$#$_], @parts
1070 my ($self, $v) = @_;
1071 my ($op, @args) = @$v;
1072 if (my $r = $self->{render_op}{$op}) {
1073 return $self->$r($op, \@args);
1075 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1076 if ($us and @args > 1) {
1077 puke "Special op '${op}' requires first value to be identifier"
1078 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1079 my $k = join(($self->{name_sep}||'.'), @$ident);
1080 local our $Expand_Depth = 1;
1081 return $self->${\($us->{handler})}($k, $op, $args[1]);
1083 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1084 return $self->${\($us->{handler})}($op, $args[0]);
1087 return $self->_render_unop_prefix($op, \@args);
1089 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1090 return '' unless @parts;
1091 my ($final_sql) = join(
1092 ' '.$self->_sqlcase($op).' ',
1097 map @{$_}[1..$#$_], @parts
1103 sub _render_op_not {
1104 my ($self, $op, $v) = @_;
1105 my ($sql, @bind) = $self->_render_unop_prefix($op, $v);
1106 return "(${sql})", @bind;
1109 sub _render_unop_prefix {
1110 my ($self, $op, $v) = @_;
1111 my ($expr_sql, @bind) = $self->render_aqt($v->[0]);
1112 my $op_sql = $self->_sqlcase($op);
1113 return ("${op_sql} ${expr_sql}", @bind);
1116 sub _render_unop_postfix {
1117 my ($self, $op, $v) = @_;
1118 my ($expr_sql, @bind) = $self->render_aqt($v->[0]);
1119 my $op_sql = $self->_sqlcase($op);
1120 return ($expr_sql.' '.$op_sql, @bind);
1123 # Some databases (SQLite) treat col IN (1, 2) different from
1124 # col IN ( (1, 2) ). Use this to strip all outer parens while
1125 # adding them back in the corresponding method
1126 sub _open_outer_paren {
1127 my ($self, $sql) = @_;
1129 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1131 # there are closing parens inside, need the heavy duty machinery
1132 # to reevaluate the extraction starting from $sql (full reevaluation)
1133 if ($inner =~ /\)/) {
1134 require Text::Balanced;
1136 my (undef, $remainder) = do {
1137 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1139 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1142 # the entire expression needs to be a balanced bracketed thing
1143 # (after an extract no remainder sans trailing space)
1144 last if defined $remainder and $remainder =~ /\S/;
1154 #======================================================================
1156 #======================================================================
1158 sub _expand_order_by {
1159 my ($self, $arg) = @_;
1161 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1163 my $expander = sub {
1164 my ($self, $dir, $expr) = @_;
1165 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1166 foreach my $arg (@to_expand) {
1170 and grep /^-(asc|desc)$/, keys %$arg
1172 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1176 defined($dir) ? { -op => [ $dir =~ /^-?(.*)$/ ,=> $_ ] } : $_
1178 map $self->expand_expr($_, -ident),
1179 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1180 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1183 local @{$self->{expand}}{qw(-asc -desc)} = (($expander) x 2);
1185 return $self->$expander(undef, $arg);
1189 my ($self, $arg) = @_;
1191 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1193 my ($sql, @bind) = $self->render_aqt($expanded);
1195 return '' unless length($sql);
1197 my $final_sql = $self->_sqlcase(' order by ').$sql;
1199 return wantarray ? ($final_sql, @bind) : $final_sql;
1202 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1204 sub _order_by_chunks {
1205 my ($self, $arg) = @_;
1207 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1209 return $self->_chunkify_order_by($expanded);
1212 sub _chunkify_order_by {
1213 my ($self, $expanded) = @_;
1215 return grep length, $self->render_aqt($expanded)
1216 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1219 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1220 return map $self->_chunkify_order_by($_), @$l;
1222 return [ $self->render_aqt($_) ];
1226 #======================================================================
1227 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1228 #======================================================================
1234 $self->_expand_maybe_list_expr($from, undef, -ident)
1239 #======================================================================
1241 #======================================================================
1243 sub _expand_maybe_list_expr {
1244 my ($self, $expr, $logic, $default) = @_;
1246 if (ref($expr) eq 'ARRAY') {
1248 map $self->expand_expr($_, $default), @$expr
1255 return $self->expand_expr($e, $default);
1258 # highly optimized, as it's called way too often
1260 # my ($self, $label) = @_;
1262 return '' unless defined $_[1];
1263 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1264 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1266 unless ($_[0]->{quote_char}) {
1267 if (ref($_[1]) eq 'ARRAY') {
1268 return join($_[0]->{name_sep}||'.', @{$_[1]});
1270 $_[0]->_assert_pass_injection_guard($_[1]);
1275 my $qref = ref $_[0]->{quote_char};
1277 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1278 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1279 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1281 my $esc = $_[0]->{escape_char} || $r;
1283 # parts containing * are naturally unquoted
1285 $_[0]->{name_sep}||'',
1289 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1291 (ref($_[1]) eq 'ARRAY'
1295 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1303 # Conversion, if applicable
1305 #my ($self, $arg) = @_;
1306 if ($_[0]->{convert_where}) {
1307 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1314 #my ($self, $col, @vals) = @_;
1315 # called often - tighten code
1316 return $_[0]->{bindtype} eq 'columns'
1317 ? map {[$_[1], $_]} @_[2 .. $#_]
1322 # Dies if any element of @bind is not in [colname => value] format
1323 # if bindtype is 'columns'.
1324 sub _assert_bindval_matches_bindtype {
1325 # my ($self, @bind) = @_;
1327 if ($self->{bindtype} eq 'columns') {
1329 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1330 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1336 sub _join_sql_clauses {
1337 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1339 if (@$clauses_aref > 1) {
1340 my $join = " " . $self->_sqlcase($logic) . " ";
1341 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1342 return ($sql, @$bind_aref);
1344 elsif (@$clauses_aref) {
1345 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1348 return (); # if no SQL, ignore @$bind_aref
1353 # Fix SQL case, if so requested
1355 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1356 # don't touch the argument ... crooked logic, but let's not change it!
1357 return $_[0]->{case} ? $_[1] : uc($_[1]);
1361 #======================================================================
1362 # DISPATCHING FROM REFKIND
1363 #======================================================================
1366 my ($self, $data) = @_;
1368 return 'UNDEF' unless defined $data;
1370 # blessed objects are treated like scalars
1371 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1373 return 'SCALAR' unless $ref;
1376 while ($ref eq 'REF') {
1378 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1382 return ($ref||'SCALAR') . ('REF' x $n_steps);
1386 my ($self, $data) = @_;
1387 my @try = ($self->_refkind($data));
1388 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1389 push @try, 'FALLBACK';
1393 sub _METHOD_FOR_refkind {
1394 my ($self, $meth_prefix, $data) = @_;
1397 for (@{$self->_try_refkind($data)}) {
1398 $method = $self->can($meth_prefix."_".$_)
1402 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1406 sub _SWITCH_refkind {
1407 my ($self, $data, $dispatch_table) = @_;
1410 for (@{$self->_try_refkind($data)}) {
1411 $coderef = $dispatch_table->{$_}
1415 puke "no dispatch entry for ".$self->_refkind($data)
1424 #======================================================================
1425 # VALUES, GENERATE, AUTOLOAD
1426 #======================================================================
1428 # LDNOTE: original code from nwiger, didn't touch code in that section
1429 # I feel the AUTOLOAD stuff should not be the default, it should
1430 # only be activated on explicit demand by user.
1434 my $data = shift || return;
1435 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1436 unless ref $data eq 'HASH';
1439 foreach my $k (sort keys %$data) {
1440 my $v = $data->{$k};
1441 $self->_SWITCH_refkind($v, {
1443 if ($self->{array_datatypes}) { # array datatype
1444 push @all_bind, $self->_bindtype($k, $v);
1446 else { # literal SQL with bind
1447 my ($sql, @bind) = @$v;
1448 $self->_assert_bindval_matches_bindtype(@bind);
1449 push @all_bind, @bind;
1452 ARRAYREFREF => sub { # literal SQL with bind
1453 my ($sql, @bind) = @${$v};
1454 $self->_assert_bindval_matches_bindtype(@bind);
1455 push @all_bind, @bind;
1457 SCALARREF => sub { # literal SQL without bind
1459 SCALAR_or_UNDEF => sub {
1460 push @all_bind, $self->_bindtype($k, $v);
1471 my(@sql, @sqlq, @sqlv);
1475 if ($ref eq 'HASH') {
1476 for my $k (sort keys %$_) {
1479 my $label = $self->_quote($k);
1480 if ($r eq 'ARRAY') {
1481 # literal SQL with bind
1482 my ($sql, @bind) = @$v;
1483 $self->_assert_bindval_matches_bindtype(@bind);
1484 push @sqlq, "$label = $sql";
1486 } elsif ($r eq 'SCALAR') {
1487 # literal SQL without bind
1488 push @sqlq, "$label = $$v";
1490 push @sqlq, "$label = ?";
1491 push @sqlv, $self->_bindtype($k, $v);
1494 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1495 } elsif ($ref eq 'ARRAY') {
1496 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1499 if ($r eq 'ARRAY') { # literal SQL with bind
1500 my ($sql, @bind) = @$v;
1501 $self->_assert_bindval_matches_bindtype(@bind);
1504 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1505 # embedded literal SQL
1512 push @sql, '(' . join(', ', @sqlq) . ')';
1513 } elsif ($ref eq 'SCALAR') {
1517 # strings get case twiddled
1518 push @sql, $self->_sqlcase($_);
1522 my $sql = join ' ', @sql;
1524 # this is pretty tricky
1525 # if ask for an array, return ($stmt, @bind)
1526 # otherwise, s/?/shift @sqlv/ to put it inline
1528 return ($sql, @sqlv);
1530 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1531 ref $d ? $d->[1] : $d/e;
1540 # This allows us to check for a local, then _form, attr
1542 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1543 return $self->generate($name, @_);
1554 SQL::Abstract - Generate SQL from Perl data structures
1560 my $sql = SQL::Abstract->new;
1562 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1564 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1566 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1568 my($stmt, @bind) = $sql->delete($table, \%where);
1570 # Then, use these in your DBI statements
1571 my $sth = $dbh->prepare($stmt);
1572 $sth->execute(@bind);
1574 # Just generate the WHERE clause
1575 my($stmt, @bind) = $sql->where(\%where, $order);
1577 # Return values in the same order, for hashed queries
1578 # See PERFORMANCE section for more details
1579 my @bind = $sql->values(\%fieldvals);
1583 This module was inspired by the excellent L<DBIx::Abstract>.
1584 However, in using that module I found that what I really wanted
1585 to do was generate SQL, but still retain complete control over my
1586 statement handles and use the DBI interface. So, I set out to
1587 create an abstract SQL generation module.
1589 While based on the concepts used by L<DBIx::Abstract>, there are
1590 several important differences, especially when it comes to WHERE
1591 clauses. I have modified the concepts used to make the SQL easier
1592 to generate from Perl data structures and, IMO, more intuitive.
1593 The underlying idea is for this module to do what you mean, based
1594 on the data structures you provide it. The big advantage is that
1595 you don't have to modify your code every time your data changes,
1596 as this module figures it out.
1598 To begin with, an SQL INSERT is as easy as just specifying a hash
1599 of C<key=value> pairs:
1602 name => 'Jimbo Bobson',
1603 phone => '123-456-7890',
1604 address => '42 Sister Lane',
1605 city => 'St. Louis',
1606 state => 'Louisiana',
1609 The SQL can then be generated with this:
1611 my($stmt, @bind) = $sql->insert('people', \%data);
1613 Which would give you something like this:
1615 $stmt = "INSERT INTO people
1616 (address, city, name, phone, state)
1617 VALUES (?, ?, ?, ?, ?)";
1618 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1619 '123-456-7890', 'Louisiana');
1621 These are then used directly in your DBI code:
1623 my $sth = $dbh->prepare($stmt);
1624 $sth->execute(@bind);
1626 =head2 Inserting and Updating Arrays
1628 If your database has array types (like for example Postgres),
1629 activate the special option C<< array_datatypes => 1 >>
1630 when creating the C<SQL::Abstract> object.
1631 Then you may use an arrayref to insert and update database array types:
1633 my $sql = SQL::Abstract->new(array_datatypes => 1);
1635 planets => [qw/Mercury Venus Earth Mars/]
1638 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1642 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1644 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1647 =head2 Inserting and Updating SQL
1649 In order to apply SQL functions to elements of your C<%data> you may
1650 specify a reference to an arrayref for the given hash value. For example,
1651 if you need to execute the Oracle C<to_date> function on a value, you can
1652 say something like this:
1656 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1659 The first value in the array is the actual SQL. Any other values are
1660 optional and would be included in the bind values array. This gives
1663 my($stmt, @bind) = $sql->insert('people', \%data);
1665 $stmt = "INSERT INTO people (name, date_entered)
1666 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1667 @bind = ('Bill', '03/02/2003');
1669 An UPDATE is just as easy, all you change is the name of the function:
1671 my($stmt, @bind) = $sql->update('people', \%data);
1673 Notice that your C<%data> isn't touched; the module will generate
1674 the appropriately quirky SQL for you automatically. Usually you'll
1675 want to specify a WHERE clause for your UPDATE, though, which is
1676 where handling C<%where> hashes comes in handy...
1678 =head2 Complex where statements
1680 This module can generate pretty complicated WHERE statements
1681 easily. For example, simple C<key=value> pairs are taken to mean
1682 equality, and if you want to see if a field is within a set
1683 of values, you can use an arrayref. Let's say we wanted to
1684 SELECT some data based on this criteria:
1687 requestor => 'inna',
1688 worker => ['nwiger', 'rcwe', 'sfz'],
1689 status => { '!=', 'completed' }
1692 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1694 The above would give you something like this:
1696 $stmt = "SELECT * FROM tickets WHERE
1697 ( requestor = ? ) AND ( status != ? )
1698 AND ( worker = ? OR worker = ? OR worker = ? )";
1699 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1701 Which you could then use in DBI code like so:
1703 my $sth = $dbh->prepare($stmt);
1704 $sth->execute(@bind);
1710 The methods are simple. There's one for every major SQL operation,
1711 and a constructor you use first. The arguments are specified in a
1712 similar order for each method (table, then fields, then a where
1713 clause) to try and simplify things.
1715 =head2 new(option => 'value')
1717 The C<new()> function takes a list of options and values, and returns
1718 a new B<SQL::Abstract> object which can then be used to generate SQL
1719 through the methods below. The options accepted are:
1725 If set to 'lower', then SQL will be generated in all lowercase. By
1726 default SQL is generated in "textbook" case meaning something like:
1728 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1730 Any setting other than 'lower' is ignored.
1734 This determines what the default comparison operator is. By default
1735 it is C<=>, meaning that a hash like this:
1737 %where = (name => 'nwiger', email => 'nate@wiger.org');
1739 Will generate SQL like this:
1741 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1743 However, you may want loose comparisons by default, so if you set
1744 C<cmp> to C<like> you would get SQL such as:
1746 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1748 You can also override the comparison on an individual basis - see
1749 the huge section on L</"WHERE CLAUSES"> at the bottom.
1751 =item sqltrue, sqlfalse
1753 Expressions for inserting boolean values within SQL statements.
1754 By default these are C<1=1> and C<1=0>. They are used
1755 by the special operators C<-in> and C<-not_in> for generating
1756 correct SQL even when the argument is an empty array (see below).
1760 This determines the default logical operator for multiple WHERE
1761 statements in arrays or hashes. If absent, the default logic is "or"
1762 for arrays, and "and" for hashes. This means that a WHERE
1766 event_date => {'>=', '2/13/99'},
1767 event_date => {'<=', '4/24/03'},
1770 will generate SQL like this:
1772 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1774 This is probably not what you want given this query, though (look
1775 at the dates). To change the "OR" to an "AND", simply specify:
1777 my $sql = SQL::Abstract->new(logic => 'and');
1779 Which will change the above C<WHERE> to:
1781 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1783 The logic can also be changed locally by inserting
1784 a modifier in front of an arrayref:
1786 @where = (-and => [event_date => {'>=', '2/13/99'},
1787 event_date => {'<=', '4/24/03'} ]);
1789 See the L</"WHERE CLAUSES"> section for explanations.
1793 This will automatically convert comparisons using the specified SQL
1794 function for both column and value. This is mostly used with an argument
1795 of C<upper> or C<lower>, so that the SQL will have the effect of
1796 case-insensitive "searches". For example, this:
1798 $sql = SQL::Abstract->new(convert => 'upper');
1799 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1801 Will turn out the following SQL:
1803 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1805 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1806 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1807 not validate this option; it will just pass through what you specify verbatim).
1811 This is a kludge because many databases suck. For example, you can't
1812 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1813 Instead, you have to use C<bind_param()>:
1815 $sth->bind_param(1, 'reg data');
1816 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1818 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1819 which loses track of which field each slot refers to. Fear not.
1821 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1822 Currently, you can specify either C<normal> (default) or C<columns>. If you
1823 specify C<columns>, you will get an array that looks like this:
1825 my $sql = SQL::Abstract->new(bindtype => 'columns');
1826 my($stmt, @bind) = $sql->insert(...);
1829 [ 'column1', 'value1' ],
1830 [ 'column2', 'value2' ],
1831 [ 'column3', 'value3' ],
1834 You can then iterate through this manually, using DBI's C<bind_param()>.
1836 $sth->prepare($stmt);
1839 my($col, $data) = @$_;
1840 if ($col eq 'details' || $col eq 'comments') {
1841 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1842 } elsif ($col eq 'image') {
1843 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1845 $sth->bind_param($i, $data);
1849 $sth->execute; # execute without @bind now
1851 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1852 Basically, the advantage is still that you don't have to care which fields
1853 are or are not included. You could wrap that above C<for> loop in a simple
1854 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1855 get a layer of abstraction over manual SQL specification.
1857 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1858 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1859 will expect the bind values in this format.
1863 This is the character that a table or column name will be quoted
1864 with. By default this is an empty string, but you could set it to
1865 the character C<`>, to generate SQL like this:
1867 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1869 Alternatively, you can supply an array ref of two items, the first being the left
1870 hand quote character, and the second the right hand quote character. For
1871 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1872 that generates SQL like this:
1874 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1876 Quoting is useful if you have tables or columns names that are reserved
1877 words in your database's SQL dialect.
1881 This is the character that will be used to escape L</quote_char>s appearing
1882 in an identifier before it has been quoted.
1884 The parameter default in case of a single L</quote_char> character is the quote
1887 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1888 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1889 of the B<opening (left)> L</quote_char> within the identifier are currently left
1890 untouched. The default for opening-closing-style quotes may change in future
1891 versions, thus you are B<strongly encouraged> to specify the escape character
1896 This is the character that separates a table and column name. It is
1897 necessary to specify this when the C<quote_char> option is selected,
1898 so that tables and column names can be individually quoted like this:
1900 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1902 =item injection_guard
1904 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1905 column name specified in a query structure. This is a safety mechanism to avoid
1906 injection attacks when mishandling user input e.g.:
1908 my %condition_as_column_value_pairs = get_values_from_user();
1909 $sqla->select( ... , \%condition_as_column_value_pairs );
1911 If the expression matches an exception is thrown. Note that literal SQL
1912 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1914 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1916 =item array_datatypes
1918 When this option is true, arrayrefs in INSERT or UPDATE are
1919 interpreted as array datatypes and are passed directly
1921 When this option is false, arrayrefs are interpreted
1922 as literal SQL, just like refs to arrayrefs
1923 (but this behavior is for backwards compatibility; when writing
1924 new queries, use the "reference to arrayref" syntax
1930 Takes a reference to a list of "special operators"
1931 to extend the syntax understood by L<SQL::Abstract>.
1932 See section L</"SPECIAL OPERATORS"> for details.
1936 Takes a reference to a list of "unary operators"
1937 to extend the syntax understood by L<SQL::Abstract>.
1938 See section L</"UNARY OPERATORS"> for details.
1944 =head2 insert($table, \@values || \%fieldvals, \%options)
1946 This is the simplest function. You simply give it a table name
1947 and either an arrayref of values or hashref of field/value pairs.
1948 It returns an SQL INSERT statement and a list of bind values.
1949 See the sections on L</"Inserting and Updating Arrays"> and
1950 L</"Inserting and Updating SQL"> for information on how to insert
1951 with those data types.
1953 The optional C<\%options> hash reference may contain additional
1954 options to generate the insert SQL. Currently supported options
1961 Takes either a scalar of raw SQL fields, or an array reference of
1962 field names, and adds on an SQL C<RETURNING> statement at the end.
1963 This allows you to return data generated by the insert statement
1964 (such as row IDs) without performing another C<SELECT> statement.
1965 Note, however, this is not part of the SQL standard and may not
1966 be supported by all database engines.
1970 =head2 update($table, \%fieldvals, \%where, \%options)
1972 This takes a table, hashref of field/value pairs, and an optional
1973 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1975 See the sections on L</"Inserting and Updating Arrays"> and
1976 L</"Inserting and Updating SQL"> for information on how to insert
1977 with those data types.
1979 The optional C<\%options> hash reference may contain additional
1980 options to generate the update SQL. Currently supported options
1987 See the C<returning> option to
1988 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1992 =head2 select($source, $fields, $where, $order)
1994 This returns a SQL SELECT statement and associated list of bind values, as
1995 specified by the arguments:
2001 Specification of the 'FROM' part of the statement.
2002 The argument can be either a plain scalar (interpreted as a table
2003 name, will be quoted), or an arrayref (interpreted as a list
2004 of table names, joined by commas, quoted), or a scalarref
2005 (literal SQL, not quoted).
2009 Specification of the list of fields to retrieve from
2011 The argument can be either an arrayref (interpreted as a list
2012 of field names, will be joined by commas and quoted), or a
2013 plain scalar (literal SQL, not quoted).
2014 Please observe that this API is not as flexible as that of
2015 the first argument C<$source>, for backwards compatibility reasons.
2019 Optional argument to specify the WHERE part of the query.
2020 The argument is most often a hashref, but can also be
2021 an arrayref or plain scalar --
2022 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2026 Optional argument to specify the ORDER BY part of the query.
2027 The argument can be a scalar, a hashref or an arrayref
2028 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2034 =head2 delete($table, \%where, \%options)
2036 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2037 It returns an SQL DELETE statement and list of bind values.
2039 The optional C<\%options> hash reference may contain additional
2040 options to generate the delete SQL. Currently supported options
2047 See the C<returning> option to
2048 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2052 =head2 where(\%where, $order)
2054 This is used to generate just the WHERE clause. For example,
2055 if you have an arbitrary data structure and know what the
2056 rest of your SQL is going to look like, but want an easy way
2057 to produce a WHERE clause, use this. It returns an SQL WHERE
2058 clause and list of bind values.
2061 =head2 values(\%data)
2063 This just returns the values from the hash C<%data>, in the same
2064 order that would be returned from any of the other above queries.
2065 Using this allows you to markedly speed up your queries if you
2066 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2068 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2070 Warning: This is an experimental method and subject to change.
2072 This returns arbitrarily generated SQL. It's a really basic shortcut.
2073 It will return two different things, depending on return context:
2075 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2076 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2078 These would return the following:
2080 # First calling form
2081 $stmt = "CREATE TABLE test (?, ?)";
2082 @bind = (field1, field2);
2084 # Second calling form
2085 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2087 Depending on what you're trying to do, it's up to you to choose the correct
2088 format. In this example, the second form is what you would want.
2092 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2096 ALTER SESSION SET nls_date_format = 'MM/YY'
2098 You get the idea. Strings get their case twiddled, but everything
2099 else remains verbatim.
2101 =head1 EXPORTABLE FUNCTIONS
2103 =head2 is_plain_value
2105 Determines if the supplied argument is a plain value as understood by this
2110 =item * The value is C<undef>
2112 =item * The value is a non-reference
2114 =item * The value is an object with stringification overloading
2116 =item * The value is of the form C<< { -value => $anything } >>
2120 On failure returns C<undef>, on success returns a B<scalar> reference
2121 to the original supplied argument.
2127 The stringification overloading detection is rather advanced: it takes
2128 into consideration not only the presence of a C<""> overload, but if that
2129 fails also checks for enabled
2130 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2131 on either C<0+> or C<bool>.
2133 Unfortunately testing in the field indicates that this
2134 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2135 but only when very large numbers of stringifying objects are involved.
2136 At the time of writing ( Sep 2014 ) there is no clear explanation of
2137 the direct cause, nor is there a manageably small test case that reliably
2138 reproduces the problem.
2140 If you encounter any of the following exceptions in B<random places within
2141 your application stack> - this module may be to blame:
2143 Operation "ne": no method found,
2144 left argument in overloaded package <something>,
2145 right argument in overloaded package <something>
2149 Stub found while resolving method "???" overloading """" in package <something>
2151 If you fall victim to the above - please attempt to reduce the problem
2152 to something that could be sent to the L<SQL::Abstract developers
2153 |DBIx::Class/GETTING HELP/SUPPORT>
2154 (either publicly or privately). As a workaround in the meantime you can
2155 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2156 value, which will most likely eliminate your problem (at the expense of
2157 not being able to properly detect exotic forms of stringification).
2159 This notice and environment variable will be removed in a future version,
2160 as soon as the underlying problem is found and a reliable workaround is
2165 =head2 is_literal_value
2167 Determines if the supplied argument is a literal value as understood by this
2172 =item * C<\$sql_string>
2174 =item * C<\[ $sql_string, @bind_values ]>
2178 On failure returns C<undef>, on success returns an B<array> reference
2179 containing the unpacked version of the supplied literal SQL and bind values.
2181 =head1 WHERE CLAUSES
2185 This module uses a variation on the idea from L<DBIx::Abstract>. It
2186 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2187 module is that things in arrays are OR'ed, and things in hashes
2190 The easiest way to explain is to show lots of examples. After
2191 each C<%where> hash shown, it is assumed you used:
2193 my($stmt, @bind) = $sql->where(\%where);
2195 However, note that the C<%where> hash can be used directly in any
2196 of the other functions as well, as described above.
2198 =head2 Key-value pairs
2200 So, let's get started. To begin, a simple hash:
2204 status => 'completed'
2207 Is converted to SQL C<key = val> statements:
2209 $stmt = "WHERE user = ? AND status = ?";
2210 @bind = ('nwiger', 'completed');
2212 One common thing I end up doing is having a list of values that
2213 a field can be in. To do this, simply specify a list inside of
2218 status => ['assigned', 'in-progress', 'pending'];
2221 This simple code will create the following:
2223 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2224 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2226 A field associated to an empty arrayref will be considered a
2227 logical false and will generate 0=1.
2229 =head2 Tests for NULL values
2231 If the value part is C<undef> then this is converted to SQL <IS NULL>
2240 $stmt = "WHERE user = ? AND status IS NULL";
2243 To test if a column IS NOT NULL:
2247 status => { '!=', undef },
2250 =head2 Specific comparison operators
2252 If you want to specify a different type of operator for your comparison,
2253 you can use a hashref for a given column:
2257 status => { '!=', 'completed' }
2260 Which would generate:
2262 $stmt = "WHERE user = ? AND status != ?";
2263 @bind = ('nwiger', 'completed');
2265 To test against multiple values, just enclose the values in an arrayref:
2267 status => { '=', ['assigned', 'in-progress', 'pending'] };
2269 Which would give you:
2271 "WHERE status = ? OR status = ? OR status = ?"
2274 The hashref can also contain multiple pairs, in which case it is expanded
2275 into an C<AND> of its elements:
2279 status => { '!=', 'completed', -not_like => 'pending%' }
2282 # Or more dynamically, like from a form
2283 $where{user} = 'nwiger';
2284 $where{status}{'!='} = 'completed';
2285 $where{status}{'-not_like'} = 'pending%';
2287 # Both generate this
2288 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2289 @bind = ('nwiger', 'completed', 'pending%');
2292 To get an OR instead, you can combine it with the arrayref idea:
2296 priority => [ { '=', 2 }, { '>', 5 } ]
2299 Which would generate:
2301 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2302 @bind = ('2', '5', 'nwiger');
2304 If you want to include literal SQL (with or without bind values), just use a
2305 scalar reference or reference to an arrayref as the value:
2308 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2309 date_expires => { '<' => \"now()" }
2312 Which would generate:
2314 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2315 @bind = ('11/26/2008');
2318 =head2 Logic and nesting operators
2320 In the example above,
2321 there is a subtle trap if you want to say something like
2322 this (notice the C<AND>):
2324 WHERE priority != ? AND priority != ?
2326 Because, in Perl you I<can't> do this:
2328 priority => { '!=' => 2, '!=' => 1 }
2330 As the second C<!=> key will obliterate the first. The solution
2331 is to use the special C<-modifier> form inside an arrayref:
2333 priority => [ -and => {'!=', 2},
2337 Normally, these would be joined by C<OR>, but the modifier tells it
2338 to use C<AND> instead. (Hint: You can use this in conjunction with the
2339 C<logic> option to C<new()> in order to change the way your queries
2340 work by default.) B<Important:> Note that the C<-modifier> goes
2341 B<INSIDE> the arrayref, as an extra first element. This will
2342 B<NOT> do what you think it might:
2344 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2346 Here is a quick list of equivalencies, since there is some overlap:
2349 status => {'!=', 'completed', 'not like', 'pending%' }
2350 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2353 status => {'=', ['assigned', 'in-progress']}
2354 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2355 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2359 =head2 Special operators: IN, BETWEEN, etc.
2361 You can also use the hashref format to compare a list of fields using the
2362 C<IN> comparison operator, by specifying the list as an arrayref:
2365 status => 'completed',
2366 reportid => { -in => [567, 2335, 2] }
2369 Which would generate:
2371 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2372 @bind = ('completed', '567', '2335', '2');
2374 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2377 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2378 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2379 'sqltrue' (by default: C<1=1>).
2381 In addition to the array you can supply a chunk of literal sql or
2382 literal sql with bind:
2385 customer => { -in => \[
2386 'SELECT cust_id FROM cust WHERE balance > ?',
2389 status => { -in => \'SELECT status_codes FROM states' },
2395 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2396 AND status IN ( SELECT status_codes FROM states )
2400 Finally, if the argument to C<-in> is not a reference, it will be
2401 treated as a single-element array.
2403 Another pair of operators is C<-between> and C<-not_between>,
2404 used with an arrayref of two values:
2408 completion_date => {
2409 -not_between => ['2002-10-01', '2003-02-06']
2415 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2417 Just like with C<-in> all plausible combinations of literal SQL
2421 start0 => { -between => [ 1, 2 ] },
2422 start1 => { -between => \["? AND ?", 1, 2] },
2423 start2 => { -between => \"lower(x) AND upper(y)" },
2424 start3 => { -between => [
2426 \["upper(?)", 'stuff' ],
2433 ( start0 BETWEEN ? AND ? )
2434 AND ( start1 BETWEEN ? AND ? )
2435 AND ( start2 BETWEEN lower(x) AND upper(y) )
2436 AND ( start3 BETWEEN lower(x) AND upper(?) )
2438 @bind = (1, 2, 1, 2, 'stuff');
2441 These are the two builtin "special operators"; but the
2442 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2444 =head2 Unary operators: bool
2446 If you wish to test against boolean columns or functions within your
2447 database you can use the C<-bool> and C<-not_bool> operators. For
2448 example to test the column C<is_user> being true and the column
2449 C<is_enabled> being false you would use:-
2453 -not_bool => 'is_enabled',
2458 WHERE is_user AND NOT is_enabled
2460 If a more complex combination is required, testing more conditions,
2461 then you should use the and/or operators:-
2466 -not_bool => { two=> { -rlike => 'bar' } },
2467 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2478 (NOT ( three = ? OR three > ? ))
2481 =head2 Nested conditions, -and/-or prefixes
2483 So far, we've seen how multiple conditions are joined with a top-level
2484 C<AND>. We can change this by putting the different conditions we want in
2485 hashes and then putting those hashes in an array. For example:
2490 status => { -like => ['pending%', 'dispatched'] },
2494 status => 'unassigned',
2498 This data structure would create the following:
2500 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2501 OR ( user = ? AND status = ? ) )";
2502 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2505 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2506 to change the logic inside:
2512 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2513 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2520 $stmt = "WHERE ( user = ?
2521 AND ( ( workhrs > ? AND geo = ? )
2522 OR ( workhrs < ? OR geo = ? ) ) )";
2523 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2525 =head3 Algebraic inconsistency, for historical reasons
2527 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2528 operator goes C<outside> of the nested structure; whereas when connecting
2529 several constraints on one column, the C<-and> operator goes
2530 C<inside> the arrayref. Here is an example combining both features:
2533 -and => [a => 1, b => 2],
2534 -or => [c => 3, d => 4],
2535 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2540 WHERE ( ( ( a = ? AND b = ? )
2541 OR ( c = ? OR d = ? )
2542 OR ( e LIKE ? AND e LIKE ? ) ) )
2544 This difference in syntax is unfortunate but must be preserved for
2545 historical reasons. So be careful: the two examples below would
2546 seem algebraically equivalent, but they are not
2549 { -like => 'foo%' },
2550 { -like => '%bar' },
2552 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2555 { col => { -like => 'foo%' } },
2556 { col => { -like => '%bar' } },
2558 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2561 =head2 Literal SQL and value type operators
2563 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2564 side" is a column name and the "right side" is a value (normally rendered as
2565 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2566 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2567 alter this behavior. There are several ways of doing so.
2571 This is a virtual operator that signals the string to its right side is an
2572 identifier (a column name) and not a value. For example to compare two
2573 columns you would write:
2576 priority => { '<', 2 },
2577 requestor => { -ident => 'submitter' },
2582 $stmt = "WHERE priority < ? AND requestor = submitter";
2585 If you are maintaining legacy code you may see a different construct as
2586 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2591 This is a virtual operator that signals that the construct to its right side
2592 is a value to be passed to DBI. This is for example necessary when you want
2593 to write a where clause against an array (for RDBMS that support such
2594 datatypes). For example:
2597 array => { -value => [1, 2, 3] }
2602 $stmt = 'WHERE array = ?';
2603 @bind = ([1, 2, 3]);
2605 Note that if you were to simply say:
2611 the result would probably not be what you wanted:
2613 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2618 Finally, sometimes only literal SQL will do. To include a random snippet
2619 of SQL verbatim, you specify it as a scalar reference. Consider this only
2620 as a last resort. Usually there is a better way. For example:
2623 priority => { '<', 2 },
2624 requestor => { -in => \'(SELECT name FROM hitmen)' },
2629 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2632 Note that in this example, you only get one bind parameter back, since
2633 the verbatim SQL is passed as part of the statement.
2637 Never use untrusted input as a literal SQL argument - this is a massive
2638 security risk (there is no way to check literal snippets for SQL
2639 injections and other nastyness). If you need to deal with untrusted input
2640 use literal SQL with placeholders as described next.
2642 =head3 Literal SQL with placeholders and bind values (subqueries)
2644 If the literal SQL to be inserted has placeholders and bind values,
2645 use a reference to an arrayref (yes this is a double reference --
2646 not so common, but perfectly legal Perl). For example, to find a date
2647 in Postgres you can use something like this:
2650 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2655 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2658 Note that you must pass the bind values in the same format as they are returned
2659 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2660 to C<columns>, you must provide the bind values in the
2661 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2662 scalar value; most commonly the column name, but you can use any scalar value
2663 (including references and blessed references), L<SQL::Abstract> will simply
2664 pass it through intact. So if C<bindtype> is set to C<columns> the above
2665 example will look like:
2668 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2671 Literal SQL is especially useful for nesting parenthesized clauses in the
2672 main SQL query. Here is a first example:
2674 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2678 bar => \["IN ($sub_stmt)" => @sub_bind],
2683 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2684 WHERE c2 < ? AND c3 LIKE ?))";
2685 @bind = (1234, 100, "foo%");
2687 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2688 are expressed in the same way. Of course the C<$sub_stmt> and
2689 its associated bind values can be generated through a former call
2692 my ($sub_stmt, @sub_bind)
2693 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2694 c3 => {-like => "foo%"}});
2697 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2700 In the examples above, the subquery was used as an operator on a column;
2701 but the same principle also applies for a clause within the main C<%where>
2702 hash, like an EXISTS subquery:
2704 my ($sub_stmt, @sub_bind)
2705 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2706 my %where = ( -and => [
2708 \["EXISTS ($sub_stmt)" => @sub_bind],
2713 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2714 WHERE c1 = ? AND c2 > t0.c0))";
2718 Observe that the condition on C<c2> in the subquery refers to
2719 column C<t0.c0> of the main query: this is I<not> a bind
2720 value, so we have to express it through a scalar ref.
2721 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2722 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2723 what we wanted here.
2725 Finally, here is an example where a subquery is used
2726 for expressing unary negation:
2728 my ($sub_stmt, @sub_bind)
2729 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2730 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2732 lname => {like => '%son%'},
2733 \["NOT ($sub_stmt)" => @sub_bind],
2738 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2739 @bind = ('%son%', 10, 20)
2741 =head3 Deprecated usage of Literal SQL
2743 Below are some examples of archaic use of literal SQL. It is shown only as
2744 reference for those who deal with legacy code. Each example has a much
2745 better, cleaner and safer alternative that users should opt for in new code.
2751 my %where = ( requestor => \'IS NOT NULL' )
2753 $stmt = "WHERE requestor IS NOT NULL"
2755 This used to be the way of generating NULL comparisons, before the handling
2756 of C<undef> got formalized. For new code please use the superior syntax as
2757 described in L</Tests for NULL values>.
2761 my %where = ( requestor => \'= submitter' )
2763 $stmt = "WHERE requestor = submitter"
2765 This used to be the only way to compare columns. Use the superior L</-ident>
2766 method for all new code. For example an identifier declared in such a way
2767 will be properly quoted if L</quote_char> is properly set, while the legacy
2768 form will remain as supplied.
2772 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2774 $stmt = "WHERE completed > ? AND is_ready"
2775 @bind = ('2012-12-21')
2777 Using an empty string literal used to be the only way to express a boolean.
2778 For all new code please use the much more readable
2779 L<-bool|/Unary operators: bool> operator.
2785 These pages could go on for a while, since the nesting of the data
2786 structures this module can handle are pretty much unlimited (the
2787 module implements the C<WHERE> expansion as a recursive function
2788 internally). Your best bet is to "play around" with the module a
2789 little to see how the data structures behave, and choose the best
2790 format for your data based on that.
2792 And of course, all the values above will probably be replaced with
2793 variables gotten from forms or the command line. After all, if you
2794 knew everything ahead of time, you wouldn't have to worry about
2795 dynamically-generating SQL and could just hardwire it into your
2798 =head1 ORDER BY CLAUSES
2800 Some functions take an order by clause. This can either be a scalar (just a
2801 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2802 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2805 Given | Will Generate
2806 ---------------------------------------------------------------
2808 'colA' | ORDER BY colA
2810 [qw/colA colB/] | ORDER BY colA, colB
2812 {-asc => 'colA'} | ORDER BY colA ASC
2814 {-desc => 'colB'} | ORDER BY colB DESC
2816 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2818 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2820 \'colA DESC' | ORDER BY colA DESC
2822 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2823 | /* ...with $x bound to ? */
2826 { -asc => 'colA' }, | colA ASC,
2827 { -desc => [qw/colB/] }, | colB DESC,
2828 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2829 \'colE DESC', | colE DESC,
2830 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2831 ] | /* ...with $x bound to ? */
2832 ===============================================================
2836 =head1 SPECIAL OPERATORS
2838 my $sqlmaker = SQL::Abstract->new(special_ops => [
2842 my ($self, $field, $op, $arg) = @_;
2848 handler => 'method_name',
2852 A "special operator" is a SQL syntactic clause that can be
2853 applied to a field, instead of a usual binary operator.
2856 WHERE field IN (?, ?, ?)
2857 WHERE field BETWEEN ? AND ?
2858 WHERE MATCH(field) AGAINST (?, ?)
2860 Special operators IN and BETWEEN are fairly standard and therefore
2861 are builtin within C<SQL::Abstract> (as the overridable methods
2862 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2863 like the MATCH .. AGAINST example above which is specific to MySQL,
2864 you can write your own operator handlers - supply a C<special_ops>
2865 argument to the C<new> method. That argument takes an arrayref of
2866 operator definitions; each operator definition is a hashref with two
2873 the regular expression to match the operator
2877 Either a coderef or a plain scalar method name. In both cases
2878 the expected return is C<< ($sql, @bind) >>.
2880 When supplied with a method name, it is simply called on the
2881 L<SQL::Abstract> object as:
2883 $self->$method_name($field, $op, $arg)
2887 $field is the LHS of the operator
2888 $op is the part that matched the handler regex
2891 When supplied with a coderef, it is called as:
2893 $coderef->($self, $field, $op, $arg)
2898 For example, here is an implementation
2899 of the MATCH .. AGAINST syntax for MySQL
2901 my $sqlmaker = SQL::Abstract->new(special_ops => [
2903 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2904 {regex => qr/^match$/i,
2906 my ($self, $field, $op, $arg) = @_;
2907 $arg = [$arg] if not ref $arg;
2908 my $label = $self->_quote($field);
2909 my ($placeholder) = $self->_convert('?');
2910 my $placeholders = join ", ", (($placeholder) x @$arg);
2911 my $sql = $self->_sqlcase('match') . " ($label) "
2912 . $self->_sqlcase('against') . " ($placeholders) ";
2913 my @bind = $self->_bindtype($field, @$arg);
2914 return ($sql, @bind);
2921 =head1 UNARY OPERATORS
2923 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2927 my ($self, $op, $arg) = @_;
2933 handler => 'method_name',
2937 A "unary operator" is a SQL syntactic clause that can be
2938 applied to a field - the operator goes before the field
2940 You can write your own operator handlers - supply a C<unary_ops>
2941 argument to the C<new> method. That argument takes an arrayref of
2942 operator definitions; each operator definition is a hashref with two
2949 the regular expression to match the operator
2953 Either a coderef or a plain scalar method name. In both cases
2954 the expected return is C<< $sql >>.
2956 When supplied with a method name, it is simply called on the
2957 L<SQL::Abstract> object as:
2959 $self->$method_name($op, $arg)
2963 $op is the part that matched the handler regex
2964 $arg is the RHS or argument of the operator
2966 When supplied with a coderef, it is called as:
2968 $coderef->($self, $op, $arg)
2976 Thanks to some benchmarking by Mark Stosberg, it turns out that
2977 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2978 I must admit this wasn't an intentional design issue, but it's a
2979 byproduct of the fact that you get to control your C<DBI> handles
2982 To maximize performance, use a code snippet like the following:
2984 # prepare a statement handle using the first row
2985 # and then reuse it for the rest of the rows
2987 for my $href (@array_of_hashrefs) {
2988 $stmt ||= $sql->insert('table', $href);
2989 $sth ||= $dbh->prepare($stmt);
2990 $sth->execute($sql->values($href));
2993 The reason this works is because the keys in your C<$href> are sorted
2994 internally by B<SQL::Abstract>. Thus, as long as your data retains
2995 the same structure, you only have to generate the SQL the first time
2996 around. On subsequent queries, simply use the C<values> function provided
2997 by this module to return your values in the correct order.
2999 However this depends on the values having the same type - if, for
3000 example, the values of a where clause may either have values
3001 (resulting in sql of the form C<column = ?> with a single bind
3002 value), or alternatively the values might be C<undef> (resulting in
3003 sql of the form C<column IS NULL> with no bind value) then the
3004 caching technique suggested will not work.
3008 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3009 really like this part (I do, at least). Building up a complex query
3010 can be as simple as the following:
3017 use CGI::FormBuilder;
3020 my $form = CGI::FormBuilder->new(...);
3021 my $sql = SQL::Abstract->new;
3023 if ($form->submitted) {
3024 my $field = $form->field;
3025 my $id = delete $field->{id};
3026 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3029 Of course, you would still have to connect using C<DBI> to run the
3030 query, but the point is that if you make your form look like your
3031 table, the actual query script can be extremely simplistic.
3033 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3034 a fast interface to returning and formatting data. I frequently
3035 use these three modules together to write complex database query
3036 apps in under 50 lines.
3038 =head1 HOW TO CONTRIBUTE
3040 Contributions are always welcome, in all usable forms (we especially
3041 welcome documentation improvements). The delivery methods include git-
3042 or unified-diff formatted patches, GitHub pull requests, or plain bug
3043 reports either via RT or the Mailing list. Contributors are generally
3044 granted full access to the official repository after their first several
3045 patches pass successful review.
3047 This project is maintained in a git repository. The code and related tools are
3048 accessible at the following locations:
3052 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3054 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3056 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3058 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3064 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3065 Great care has been taken to preserve the I<published> behavior
3066 documented in previous versions in the 1.* family; however,
3067 some features that were previously undocumented, or behaved
3068 differently from the documentation, had to be changed in order
3069 to clarify the semantics. Hence, client code that was relying
3070 on some dark areas of C<SQL::Abstract> v1.*
3071 B<might behave differently> in v1.50.
3073 The main changes are:
3079 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3083 support for the { operator => \"..." } construct (to embed literal SQL)
3087 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3091 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3095 defensive programming: check arguments
3099 fixed bug with global logic, which was previously implemented
3100 through global variables yielding side-effects. Prior versions would
3101 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3102 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3103 Now this is interpreted
3104 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3109 fixed semantics of _bindtype on array args
3113 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3114 we just avoid shifting arrays within that tree.
3118 dropped the C<_modlogic> function
3122 =head1 ACKNOWLEDGEMENTS
3124 There are a number of individuals that have really helped out with
3125 this module. Unfortunately, most of them submitted bugs via CPAN
3126 so I have no idea who they are! But the people I do know are:
3128 Ash Berlin (order_by hash term support)
3129 Matt Trout (DBIx::Class support)
3130 Mark Stosberg (benchmarking)
3131 Chas Owens (initial "IN" operator support)
3132 Philip Collins (per-field SQL functions)
3133 Eric Kolve (hashref "AND" support)
3134 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3135 Dan Kubb (support for "quote_char" and "name_sep")
3136 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3137 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3138 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3139 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3140 Oliver Charles (support for "RETURNING" after "INSERT")
3146 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3150 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3152 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3154 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3155 While not an official support venue, C<DBIx::Class> makes heavy use of
3156 C<SQL::Abstract>, and as such list members there are very familiar with
3157 how to create queries.
3161 This module is free software; you may copy this under the same
3162 terms as perl itself (either the GNU General Public License or
3163 the Artistic License)