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 -ident => '_expand_ident',
191 -value => '_expand_value',
192 -not => '_expand_not',
193 -bool => '_expand_bool',
194 -and => '_expand_andor',
195 -or => '_expand_andor',
198 $opt{render_op} = our $RENDER_OP;
201 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
205 return bless \%opt, $class;
208 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
209 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
211 sub _assert_pass_injection_guard {
212 if ($_[1] =~ $_[0]->{injection_guard}) {
213 my $class = ref $_[0];
214 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
215 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
216 . "{injection_guard} attribute to ${class}->new()"
221 #======================================================================
223 #======================================================================
227 my $table = $self->_table(shift);
228 my $data = shift || return;
231 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
232 my ($sql, @bind) = $self->$method($data);
233 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
235 if ($options->{returning}) {
236 my ($s, @b) = $self->_insert_returning($options);
241 return wantarray ? ($sql, @bind) : $sql;
244 # So that subclasses can override INSERT ... RETURNING separately from
245 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
246 sub _insert_returning { shift->_returning(@_) }
249 my ($self, $options) = @_;
251 my $f = $options->{returning};
253 my ($sql, @bind) = $self->render_aqt(
254 $self->_expand_maybe_list_expr($f, undef, -ident)
257 ? $self->_sqlcase(' returning ') . $sql
258 : ($self->_sqlcase(' returning ').$sql, @bind);
261 sub _insert_HASHREF { # explicit list of fields and then values
262 my ($self, $data) = @_;
264 my @fields = sort keys %$data;
266 my ($sql, @bind) = $self->_insert_values($data);
269 $_ = $self->_quote($_) foreach @fields;
270 $sql = "( ".join(", ", @fields).") ".$sql;
272 return ($sql, @bind);
275 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
276 my ($self, $data) = @_;
278 # no names (arrayref) so can't generate bindtype
279 $self->{bindtype} ne 'columns'
280 or belch "can't do 'columns' bindtype when called with arrayref";
282 my (@values, @all_bind);
283 foreach my $value (@$data) {
284 my ($values, @bind) = $self->_insert_value(undef, $value);
285 push @values, $values;
286 push @all_bind, @bind;
288 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
289 return ($sql, @all_bind);
292 sub _insert_ARRAYREFREF { # literal SQL with bind
293 my ($self, $data) = @_;
295 my ($sql, @bind) = @${$data};
296 $self->_assert_bindval_matches_bindtype(@bind);
298 return ($sql, @bind);
302 sub _insert_SCALARREF { # literal SQL without bind
303 my ($self, $data) = @_;
309 my ($self, $data) = @_;
311 my (@values, @all_bind);
312 foreach my $column (sort keys %$data) {
313 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
314 push @values, $values;
315 push @all_bind, @bind;
317 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
318 return ($sql, @all_bind);
322 my ($self, $column, $v) = @_;
324 return $self->render_aqt(
325 $self->_expand_insert_value($column, $v)
329 sub _expand_insert_value {
330 my ($self, $column, $v) = @_;
332 if (ref($v) eq 'ARRAY') {
333 if ($self->{array_datatypes}) {
334 return +{ -bind => [ $column, $v ] };
336 my ($sql, @bind) = @$v;
337 $self->_assert_bindval_matches_bindtype(@bind);
338 return +{ -literal => $v };
340 if (ref($v) eq 'HASH') {
341 if (grep !/^-/, keys %$v) {
342 belch "HASH ref as bind value in insert is not supported";
343 return +{ -bind => [ $column, $v ] };
347 return +{ -bind => [ $column, undef ] };
349 local our $Cur_Col_Meta = $column;
350 return $self->expand_expr($v);
355 #======================================================================
357 #======================================================================
362 my $table = $self->_table(shift);
363 my $data = shift || return;
367 # first build the 'SET' part of the sql statement
368 puke "Unsupported data type specified to \$sql->update"
369 unless ref $data eq 'HASH';
371 my ($sql, @all_bind) = $self->_update_set_values($data);
372 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
376 my($where_sql, @where_bind) = $self->where($where);
378 push @all_bind, @where_bind;
381 if ($options->{returning}) {
382 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
383 $sql .= $returning_sql;
384 push @all_bind, @returning_bind;
387 return wantarray ? ($sql, @all_bind) : $sql;
390 sub _update_set_values {
391 my ($self, $data) = @_;
393 return $self->render_aqt(
394 $self->_expand_update_set_values($data),
398 sub _expand_update_set_values {
399 my ($self, $data) = @_;
400 $self->_expand_maybe_list_expr( [
403 $set = { -bind => $_ } unless defined $set;
404 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
410 ? ($self->{array_datatypes}
411 ? [ $k, +{ -bind => [ $k, $v ] } ]
412 : [ $k, +{ -literal => $v } ])
414 local our $Cur_Col_Meta = $k;
415 [ $k, $self->_expand_expr($v) ]
422 # So that subclasses can override UPDATE ... RETURNING separately from
424 sub _update_returning { shift->_returning(@_) }
428 #======================================================================
430 #======================================================================
435 my $table = $self->_table(shift);
436 my $fields = shift || '*';
440 my ($fields_sql, @bind) = $self->_select_fields($fields);
442 my ($where_sql, @where_bind) = $self->where($where, $order);
443 push @bind, @where_bind;
445 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
446 $self->_sqlcase('from'), $table)
449 return wantarray ? ($sql, @bind) : $sql;
453 my ($self, $fields) = @_;
454 return $fields unless ref($fields);
455 return $self->render_aqt(
456 $self->_expand_maybe_list_expr($fields, undef, '-ident')
460 #======================================================================
462 #======================================================================
467 my $table = $self->_table(shift);
471 my($where_sql, @bind) = $self->where($where);
472 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
474 if ($options->{returning}) {
475 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
476 $sql .= $returning_sql;
477 push @bind, @returning_bind;
480 return wantarray ? ($sql, @bind) : $sql;
483 # So that subclasses can override DELETE ... RETURNING separately from
485 sub _delete_returning { shift->_returning(@_) }
489 #======================================================================
491 #======================================================================
495 # Finally, a separate routine just to handle WHERE clauses
497 my ($self, $where, $order) = @_;
499 local $self->{convert_where} = $self->{convert};
502 my ($sql, @bind) = defined($where)
503 ? $self->_recurse_where($where)
505 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
509 my ($order_sql, @order_bind) = $self->_order_by($order);
511 push @bind, @order_bind;
514 return wantarray ? ($sql, @bind) : $sql;
518 my ($self, $expr, $default_scalar_to) = @_;
519 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
520 $self->_expand_expr($expr);
524 my ($self, $aqt) = @_;
525 my ($k, $v, @rest) = %$aqt;
527 if (my $meth = $self->{render}{$k}) {
528 return $self->$meth($v);
530 die "notreached: $k";
534 my ($self, $expr) = @_;
535 $self->render_aqt($self->expand_expr($expr));
539 my ($self, $expr, $logic) = @_;
540 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
541 return undef unless defined($expr);
542 if (ref($expr) eq 'HASH') {
543 return undef unless my $kc = keys %$expr;
546 return $self->_expand_andor("-${logic}", $expr);
548 my ($key, $value) = %$expr;
549 if ($key =~ /^-/ and $key =~ s/ [_\s]? \d+ $//x ) {
550 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
551 . "You probably wanted ...-and => [ $key => COND1, $key => COND2 ... ]";
553 if (my $exp = $self->{expand}{$key}) {
554 return $self->$exp($key, $value);
556 return $self->_expand_expr_hashpair($key, $value, $logic);
558 if (ref($expr) eq 'ARRAY') {
559 my $logic = lc($logic || $self->{logic});
560 return $self->_expand_andor("-${logic}", $expr);
562 if (my $literal = is_literal_value($expr)) {
563 return +{ -literal => $literal };
565 if (!ref($expr) or Scalar::Util::blessed($expr)) {
566 if (my $d = our $Default_Scalar_To) {
567 return $self->_expand_expr({ $d => $expr });
569 return $self->_expand_value(-value => $expr);
574 sub _expand_expr_hashpair {
575 my ($self, $k, $v, $logic) = @_;
576 unless (defined($k) and length($k)) {
577 if (defined($k) and my $literal = is_literal_value($v)) {
578 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
579 return { -literal => $literal };
581 puke "Supplying an empty left hand side argument is not supported";
584 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
586 # DBIx::Class requires a nest warning to be emitted once but the private
587 # method it overrode to do so no longer exists
588 if ($self->{is_dbic_sqlmaker}) {
589 unless (our $Nest_Warned) {
591 "-nest in search conditions is deprecated, you most probably wanted:\n"
592 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
597 return $self->_expand_expr($v);
599 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
602 $self->_expand_expr({ "-${rest}", $v }, $logic)
607 $op =~ s/^-// if length($op) > 1;
609 # top level special ops are illegal in general
610 # note that, arguably, if it makes no sense at top level, it also
611 # makes no sense on the other side of an = sign or similar but DBIC
612 # gets disappointingly upset if I disallow it
614 (our $Expand_Depth) == 1
615 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
617 puke "Illegal use of top-level '-$op'"
619 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
620 return { -op => [ $op, $v ] };
623 if ($self->{render}{$k}) {
629 and (keys %$v)[0] =~ /^-/
631 my ($func) = $k =~ /^-(.*)$/;
632 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
633 return +{ -op => [ $func, $self->_expand_expr($v) ] };
635 return +{ -func => [ $func, $self->_expand_expr($v) ] };
637 if (!ref($v) or is_literal_value($v)) {
638 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
645 and exists $v->{-value}
646 and not defined $v->{-value}
649 return $self->_expand_expr({ $k => { $self->{cmp} => undef } });
651 if (!ref($v) or Scalar::Util::blessed($v)) {
652 my $d = our $Default_Scalar_To;
656 $self->_expand_ident(-ident => $k),
658 ? $self->_expand_expr($d => $v)
659 : { -bind => [ $k, $v ] }
664 if (ref($v) eq 'HASH') {
668 map $self->_expand_expr({ $k => { $_ => $v->{$_} } }),
672 return undef unless keys %$v;
674 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
675 $self->_assert_pass_injection_guard($op);
676 if ($op =~ s/ [_\s]? \d+ $//x ) {
677 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
678 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
680 if ($op =~ /^(?:not )?between$/) {
681 local our $Cur_Col_Meta = $k;
682 my @rhs = map $self->_expand_expr($_),
683 ref($vv) eq 'ARRAY' ? @$vv : $vv;
685 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
687 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
689 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
693 $self->_expand_ident(-ident => $k),
697 if ($op =~ /^(?:not )?in$/) {
698 if (my $literal = is_literal_value($vv)) {
699 my ($sql, @bind) = @$literal;
700 my $opened_sql = $self->_open_outer_paren($sql);
702 $op, $self->_expand_ident(-ident => $k),
703 [ { -literal => [ $opened_sql, @bind ] } ]
707 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
708 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
709 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
710 . 'will emit the logically correct SQL instead of raising this exception)'
712 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
714 my @rhs = map $self->_expand_expr($_),
715 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
716 map { defined($_) ? $_: puke($undef_err) }
717 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
718 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
722 $self->_expand_ident(-ident => $k),
726 if ($op eq 'ident') {
727 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
728 puke "-$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
732 $self->_expand_ident(-ident => $k),
733 $self->_expand_ident(-ident => $vv),
736 if ($op eq 'value') {
737 return $self->_expand_expr({ $k, undef }) unless defined($vv);
740 $self->_expand_ident(-ident => $k),
741 { -bind => [ $k, $vv ] }
744 if ($op =~ /^is(?: not)?$/) {
745 puke "$op can only take undef as argument"
749 and exists($vv->{-value})
750 and !defined($vv->{-value})
752 return +{ -op => [ $op.' null', $self->_expand_ident(-ident => $k) ] };
754 if ($op =~ /^(and|or)$/) {
755 if (ref($vv) eq 'HASH') {
758 map $self->_expand_expr({ $k, { $_ => $vv->{$_} } }),
763 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
764 return { -op => [ $op, $self->_expand_ident(-ident => $k), $vv ] };
766 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
769 $self->_expand_ident(-ident => $k),
770 { -op => [ $op, $vv ] }
773 if (ref($vv) eq 'ARRAY') {
774 my ($logic, @values) = (
775 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
780 $op =~ $self->{inequality_op}
781 or $op =~ $self->{not_like_op}
783 if (lc($logic) eq '-or' and @values > 1) {
784 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
785 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
786 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
791 # try to DWIM on equality operators
793 $op =~ $self->{equality_op} ? $self->sqlfalse
794 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
795 : $op =~ $self->{inequality_op} ? $self->sqltrue
796 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
797 : puke "operator '$op' applied on an empty array (field '$k')";
801 map $self->_expand_expr({ $k => { $vk => $_ } }),
809 and exists $vv->{-value}
810 and not defined $vv->{-value}
814 $op =~ /^not$/i ? 'is not' # legacy
815 : $op =~ $self->{equality_op} ? 'is'
816 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
817 : $op =~ $self->{inequality_op} ? 'is not'
818 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
819 : puke "unexpected operator '$op' with undef operand";
820 return +{ -op => [ $is.' null', $self->_expand_ident(-ident => $k) ] };
822 local our $Cur_Col_Meta = $k;
825 $self->_expand_ident(-ident => $k),
826 $self->_expand_expr($vv)
829 if (ref($v) eq 'ARRAY') {
830 return $self->sqlfalse unless @$v;
831 $self->_debug("ARRAY($k) means distribute over elements");
833 $v->[0] =~ /^-(and|or)$/i
834 ? shift(@{$v = [ @$v ]})
835 : '-'.($self->{logic} || 'or')
837 return $self->_expand_expr({
838 $this_logic => [ map +{ $k => $_ }, @$v ]
841 if (my $literal = is_literal_value($v)) {
843 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
846 my ($sql, @bind) = @$literal;
847 if ($self->{bindtype} eq 'columns') {
849 $self->_assert_bindval_matches_bindtype($_);
852 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
858 my ($self, undef, $body) = @_;
859 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
860 ref($body) ? @$body : $body;
861 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
862 unless ($self->{quote_char}) {
863 $self->_assert_pass_injection_guard($_) for @parts;
865 return +{ -ident => \@parts };
869 +{ -bind => [ our $Cur_Col_Meta, $_[2] ] };
873 +{ -op => [ 'not', $_[0]->_expand_expr($_[2]) ] };
877 my ($self, undef, $v) = @_;
879 return $self->_expand_expr($v);
881 puke "-bool => undef not supported" unless defined($v);
882 return $self->_expand_ident(-ident => $v);
886 my ($self, $k, $v) = @_;
887 my ($logic) = $k =~ /^-(.*)$/;
888 if (ref($v) eq 'HASH') {
891 map $self->_expand_expr({ $_ => $v->{$_} }, $logic),
895 if (ref($v) eq 'ARRAY') {
896 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
899 (ref($_) eq 'ARRAY' and @$_)
900 or (ref($_) eq 'HASH' and %$_)
906 while (my ($el) = splice @expr, 0, 1) {
907 puke "Supplying an empty left hand side argument is not supported in array-pairs"
908 unless defined($el) and length($el);
909 my $elref = ref($el);
911 local our $Expand_Depth = 0;
912 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
913 } elsif ($elref eq 'ARRAY') {
914 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
915 } elsif (my $l = is_literal_value($el)) {
916 push @res, { -literal => $l };
917 } elsif ($elref eq 'HASH') {
918 local our $Expand_Depth = 0;
919 push @res, grep defined, $self->_expand_expr($el) if %$el;
925 # return $res[0] if @res == 1;
926 return { -op => [ $logic, @res ] };
932 my ($self, $where, $logic) = @_;
934 # Special case: top level simple string treated as literal
936 my $where_exp = (ref($where)
937 ? $self->_expand_expr($where, $logic)
938 : { -literal => [ $where ] });
940 # dispatch expanded expression
942 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
943 # DBIx::Class used to call _recurse_where in scalar context
944 # something else might too...
946 return ($sql, @bind);
949 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
955 my ($self, $ident) = @_;
957 return $self->_convert($self->_quote($ident));
961 my ($self, $list) = @_;
962 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
963 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
967 my ($self, $rest) = @_;
968 my ($func, @args) = @$rest;
972 push @arg_sql, shift @x;
974 } map [ $self->render_aqt($_) ], @args;
975 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
979 my ($self, $bind) = @_;
980 return ($self->_convert('?'), $self->_bindtype(@$bind));
983 sub _render_literal {
984 my ($self, $literal) = @_;
985 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
991 my ($self, $op, $args) = @_;
992 my ($left, $low, $high) = @$args;
993 my ($rhsql, @rhbind) = do {
995 puke "Single arg to between must be a literal"
996 unless $low->{-literal};
999 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
1000 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
1001 @{$l}[1..$#$l], @{$h}[1..$#$h])
1004 my ($lhsql, @lhbind) = $self->render_aqt($left);
1006 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
1009 }), 'between', 'not between'),
1011 my ($self, $op, $args) = @_;
1012 my ($lhs, $rhs) = @$args;
1015 my ($sql, @bind) = $self->render_aqt($_);
1016 push @in_bind, @bind;
1019 my ($lhsql, @lbind) = $self->render_aqt($lhs);
1021 $lhsql.' '.$self->_sqlcase($op).' ( '
1022 .join(', ', @in_sql)
1026 }), 'in', 'not in'),
1027 (map +($_ => '_render_unop_postfix'),
1028 'is null', 'is not null', 'asc', 'desc',
1030 (not => '_render_op_not'),
1032 my ($self, $op, $args) = @_;
1033 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$args;
1034 return '' unless @parts;
1035 return @{$parts[0]} if @parts == 1;
1036 my ($final_sql) = join(
1037 ' '.$self->_sqlcase($op).' ',
1042 map @{$_}[1..$#$_], @parts
1048 my ($self, $v) = @_;
1049 my ($op, @args) = @$v;
1050 if (my $r = $self->{render_op}{$op}) {
1051 return $self->$r($op, \@args);
1053 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1054 if ($us and @args > 1) {
1055 puke "Special op '${op}' requires first value to be identifier"
1056 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1057 my $k = join(($self->{name_sep}||'.'), @$ident);
1058 local our $Expand_Depth = 1;
1059 return $self->${\($us->{handler})}($k, $op, $args[1]);
1061 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1062 return $self->${\($us->{handler})}($op, $args[0]);
1065 return $self->_render_unop_prefix($op, \@args);
1067 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1068 return '' unless @parts;
1069 my ($final_sql) = join(
1070 ' '.$self->_sqlcase($op).' ',
1075 map @{$_}[1..$#$_], @parts
1081 sub _render_op_not {
1082 my ($self, $op, $v) = @_;
1083 my ($sql, @bind) = $self->_render_unop_prefix($op, $v);
1084 return "(${sql})", @bind;
1087 sub _render_unop_prefix {
1088 my ($self, $op, $v) = @_;
1089 my ($expr_sql, @bind) = $self->render_aqt($v->[0]);
1090 my $op_sql = $self->_sqlcase($op);
1091 return ("${op_sql} ${expr_sql}", @bind);
1094 sub _render_unop_postfix {
1095 my ($self, $op, $v) = @_;
1096 my ($expr_sql, @bind) = $self->render_aqt($v->[0]);
1097 my $op_sql = $self->_sqlcase($op);
1098 return ($expr_sql.' '.$op_sql, @bind);
1101 # Some databases (SQLite) treat col IN (1, 2) different from
1102 # col IN ( (1, 2) ). Use this to strip all outer parens while
1103 # adding them back in the corresponding method
1104 sub _open_outer_paren {
1105 my ($self, $sql) = @_;
1107 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1109 # there are closing parens inside, need the heavy duty machinery
1110 # to reevaluate the extraction starting from $sql (full reevaluation)
1111 if ($inner =~ /\)/) {
1112 require Text::Balanced;
1114 my (undef, $remainder) = do {
1115 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1117 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1120 # the entire expression needs to be a balanced bracketed thing
1121 # (after an extract no remainder sans trailing space)
1122 last if defined $remainder and $remainder =~ /\S/;
1132 #======================================================================
1134 #======================================================================
1136 sub _expand_order_by {
1137 my ($self, $arg) = @_;
1139 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1141 my $expander = sub {
1142 my ($self, $dir, $expr) = @_;
1143 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1144 foreach my $arg (@to_expand) {
1148 and grep /^-(asc|desc)$/, keys %$arg
1150 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1154 defined($dir) ? { -op => [ $dir =~ /^-?(.*)$/ ,=> $_ ] } : $_
1156 map $self->expand_expr($_, -ident),
1157 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1158 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1161 local @{$self->{expand}}{qw(-asc -desc)} = (($expander) x 2);
1163 return $self->$expander(undef, $arg);
1167 my ($self, $arg) = @_;
1169 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1171 my ($sql, @bind) = $self->render_aqt($expanded);
1173 return '' unless length($sql);
1175 my $final_sql = $self->_sqlcase(' order by ').$sql;
1177 return wantarray ? ($final_sql, @bind) : $final_sql;
1180 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1182 sub _order_by_chunks {
1183 my ($self, $arg) = @_;
1185 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1187 return $self->_chunkify_order_by($expanded);
1190 sub _chunkify_order_by {
1191 my ($self, $expanded) = @_;
1193 return grep length, $self->render_aqt($expanded)
1194 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1197 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1198 return map $self->_chunkify_order_by($_), @$l;
1200 return [ $self->render_aqt($_) ];
1204 #======================================================================
1205 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1206 #======================================================================
1212 $self->_expand_maybe_list_expr($from, undef, -ident)
1217 #======================================================================
1219 #======================================================================
1221 sub _expand_maybe_list_expr {
1222 my ($self, $expr, $logic, $default) = @_;
1224 if (ref($expr) eq 'ARRAY') {
1226 map $self->expand_expr($_, $default), @$expr
1233 return $self->expand_expr($e, $default);
1236 # highly optimized, as it's called way too often
1238 # my ($self, $label) = @_;
1240 return '' unless defined $_[1];
1241 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1242 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1244 unless ($_[0]->{quote_char}) {
1245 if (ref($_[1]) eq 'ARRAY') {
1246 return join($_[0]->{name_sep}||'.', @{$_[1]});
1248 $_[0]->_assert_pass_injection_guard($_[1]);
1253 my $qref = ref $_[0]->{quote_char};
1255 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1256 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1257 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1259 my $esc = $_[0]->{escape_char} || $r;
1261 # parts containing * are naturally unquoted
1263 $_[0]->{name_sep}||'',
1267 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1269 (ref($_[1]) eq 'ARRAY'
1273 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1281 # Conversion, if applicable
1283 #my ($self, $arg) = @_;
1284 if ($_[0]->{convert_where}) {
1285 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1292 #my ($self, $col, @vals) = @_;
1293 # called often - tighten code
1294 return $_[0]->{bindtype} eq 'columns'
1295 ? map {[$_[1], $_]} @_[2 .. $#_]
1300 # Dies if any element of @bind is not in [colname => value] format
1301 # if bindtype is 'columns'.
1302 sub _assert_bindval_matches_bindtype {
1303 # my ($self, @bind) = @_;
1305 if ($self->{bindtype} eq 'columns') {
1307 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1308 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1314 sub _join_sql_clauses {
1315 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1317 if (@$clauses_aref > 1) {
1318 my $join = " " . $self->_sqlcase($logic) . " ";
1319 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1320 return ($sql, @$bind_aref);
1322 elsif (@$clauses_aref) {
1323 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1326 return (); # if no SQL, ignore @$bind_aref
1331 # Fix SQL case, if so requested
1333 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1334 # don't touch the argument ... crooked logic, but let's not change it!
1335 return $_[0]->{case} ? $_[1] : uc($_[1]);
1339 #======================================================================
1340 # DISPATCHING FROM REFKIND
1341 #======================================================================
1344 my ($self, $data) = @_;
1346 return 'UNDEF' unless defined $data;
1348 # blessed objects are treated like scalars
1349 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1351 return 'SCALAR' unless $ref;
1354 while ($ref eq 'REF') {
1356 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1360 return ($ref||'SCALAR') . ('REF' x $n_steps);
1364 my ($self, $data) = @_;
1365 my @try = ($self->_refkind($data));
1366 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1367 push @try, 'FALLBACK';
1371 sub _METHOD_FOR_refkind {
1372 my ($self, $meth_prefix, $data) = @_;
1375 for (@{$self->_try_refkind($data)}) {
1376 $method = $self->can($meth_prefix."_".$_)
1380 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1384 sub _SWITCH_refkind {
1385 my ($self, $data, $dispatch_table) = @_;
1388 for (@{$self->_try_refkind($data)}) {
1389 $coderef = $dispatch_table->{$_}
1393 puke "no dispatch entry for ".$self->_refkind($data)
1402 #======================================================================
1403 # VALUES, GENERATE, AUTOLOAD
1404 #======================================================================
1406 # LDNOTE: original code from nwiger, didn't touch code in that section
1407 # I feel the AUTOLOAD stuff should not be the default, it should
1408 # only be activated on explicit demand by user.
1412 my $data = shift || return;
1413 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1414 unless ref $data eq 'HASH';
1417 foreach my $k (sort keys %$data) {
1418 my $v = $data->{$k};
1419 $self->_SWITCH_refkind($v, {
1421 if ($self->{array_datatypes}) { # array datatype
1422 push @all_bind, $self->_bindtype($k, $v);
1424 else { # literal SQL with bind
1425 my ($sql, @bind) = @$v;
1426 $self->_assert_bindval_matches_bindtype(@bind);
1427 push @all_bind, @bind;
1430 ARRAYREFREF => sub { # literal SQL with bind
1431 my ($sql, @bind) = @${$v};
1432 $self->_assert_bindval_matches_bindtype(@bind);
1433 push @all_bind, @bind;
1435 SCALARREF => sub { # literal SQL without bind
1437 SCALAR_or_UNDEF => sub {
1438 push @all_bind, $self->_bindtype($k, $v);
1449 my(@sql, @sqlq, @sqlv);
1453 if ($ref eq 'HASH') {
1454 for my $k (sort keys %$_) {
1457 my $label = $self->_quote($k);
1458 if ($r eq 'ARRAY') {
1459 # literal SQL with bind
1460 my ($sql, @bind) = @$v;
1461 $self->_assert_bindval_matches_bindtype(@bind);
1462 push @sqlq, "$label = $sql";
1464 } elsif ($r eq 'SCALAR') {
1465 # literal SQL without bind
1466 push @sqlq, "$label = $$v";
1468 push @sqlq, "$label = ?";
1469 push @sqlv, $self->_bindtype($k, $v);
1472 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1473 } elsif ($ref eq 'ARRAY') {
1474 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1477 if ($r eq 'ARRAY') { # literal SQL with bind
1478 my ($sql, @bind) = @$v;
1479 $self->_assert_bindval_matches_bindtype(@bind);
1482 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1483 # embedded literal SQL
1490 push @sql, '(' . join(', ', @sqlq) . ')';
1491 } elsif ($ref eq 'SCALAR') {
1495 # strings get case twiddled
1496 push @sql, $self->_sqlcase($_);
1500 my $sql = join ' ', @sql;
1502 # this is pretty tricky
1503 # if ask for an array, return ($stmt, @bind)
1504 # otherwise, s/?/shift @sqlv/ to put it inline
1506 return ($sql, @sqlv);
1508 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1509 ref $d ? $d->[1] : $d/e;
1518 # This allows us to check for a local, then _form, attr
1520 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1521 return $self->generate($name, @_);
1532 SQL::Abstract - Generate SQL from Perl data structures
1538 my $sql = SQL::Abstract->new;
1540 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1542 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1544 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1546 my($stmt, @bind) = $sql->delete($table, \%where);
1548 # Then, use these in your DBI statements
1549 my $sth = $dbh->prepare($stmt);
1550 $sth->execute(@bind);
1552 # Just generate the WHERE clause
1553 my($stmt, @bind) = $sql->where(\%where, $order);
1555 # Return values in the same order, for hashed queries
1556 # See PERFORMANCE section for more details
1557 my @bind = $sql->values(\%fieldvals);
1561 This module was inspired by the excellent L<DBIx::Abstract>.
1562 However, in using that module I found that what I really wanted
1563 to do was generate SQL, but still retain complete control over my
1564 statement handles and use the DBI interface. So, I set out to
1565 create an abstract SQL generation module.
1567 While based on the concepts used by L<DBIx::Abstract>, there are
1568 several important differences, especially when it comes to WHERE
1569 clauses. I have modified the concepts used to make the SQL easier
1570 to generate from Perl data structures and, IMO, more intuitive.
1571 The underlying idea is for this module to do what you mean, based
1572 on the data structures you provide it. The big advantage is that
1573 you don't have to modify your code every time your data changes,
1574 as this module figures it out.
1576 To begin with, an SQL INSERT is as easy as just specifying a hash
1577 of C<key=value> pairs:
1580 name => 'Jimbo Bobson',
1581 phone => '123-456-7890',
1582 address => '42 Sister Lane',
1583 city => 'St. Louis',
1584 state => 'Louisiana',
1587 The SQL can then be generated with this:
1589 my($stmt, @bind) = $sql->insert('people', \%data);
1591 Which would give you something like this:
1593 $stmt = "INSERT INTO people
1594 (address, city, name, phone, state)
1595 VALUES (?, ?, ?, ?, ?)";
1596 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1597 '123-456-7890', 'Louisiana');
1599 These are then used directly in your DBI code:
1601 my $sth = $dbh->prepare($stmt);
1602 $sth->execute(@bind);
1604 =head2 Inserting and Updating Arrays
1606 If your database has array types (like for example Postgres),
1607 activate the special option C<< array_datatypes => 1 >>
1608 when creating the C<SQL::Abstract> object.
1609 Then you may use an arrayref to insert and update database array types:
1611 my $sql = SQL::Abstract->new(array_datatypes => 1);
1613 planets => [qw/Mercury Venus Earth Mars/]
1616 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1620 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1622 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1625 =head2 Inserting and Updating SQL
1627 In order to apply SQL functions to elements of your C<%data> you may
1628 specify a reference to an arrayref for the given hash value. For example,
1629 if you need to execute the Oracle C<to_date> function on a value, you can
1630 say something like this:
1634 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1637 The first value in the array is the actual SQL. Any other values are
1638 optional and would be included in the bind values array. This gives
1641 my($stmt, @bind) = $sql->insert('people', \%data);
1643 $stmt = "INSERT INTO people (name, date_entered)
1644 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1645 @bind = ('Bill', '03/02/2003');
1647 An UPDATE is just as easy, all you change is the name of the function:
1649 my($stmt, @bind) = $sql->update('people', \%data);
1651 Notice that your C<%data> isn't touched; the module will generate
1652 the appropriately quirky SQL for you automatically. Usually you'll
1653 want to specify a WHERE clause for your UPDATE, though, which is
1654 where handling C<%where> hashes comes in handy...
1656 =head2 Complex where statements
1658 This module can generate pretty complicated WHERE statements
1659 easily. For example, simple C<key=value> pairs are taken to mean
1660 equality, and if you want to see if a field is within a set
1661 of values, you can use an arrayref. Let's say we wanted to
1662 SELECT some data based on this criteria:
1665 requestor => 'inna',
1666 worker => ['nwiger', 'rcwe', 'sfz'],
1667 status => { '!=', 'completed' }
1670 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1672 The above would give you something like this:
1674 $stmt = "SELECT * FROM tickets WHERE
1675 ( requestor = ? ) AND ( status != ? )
1676 AND ( worker = ? OR worker = ? OR worker = ? )";
1677 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1679 Which you could then use in DBI code like so:
1681 my $sth = $dbh->prepare($stmt);
1682 $sth->execute(@bind);
1688 The methods are simple. There's one for every major SQL operation,
1689 and a constructor you use first. The arguments are specified in a
1690 similar order for each method (table, then fields, then a where
1691 clause) to try and simplify things.
1693 =head2 new(option => 'value')
1695 The C<new()> function takes a list of options and values, and returns
1696 a new B<SQL::Abstract> object which can then be used to generate SQL
1697 through the methods below. The options accepted are:
1703 If set to 'lower', then SQL will be generated in all lowercase. By
1704 default SQL is generated in "textbook" case meaning something like:
1706 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1708 Any setting other than 'lower' is ignored.
1712 This determines what the default comparison operator is. By default
1713 it is C<=>, meaning that a hash like this:
1715 %where = (name => 'nwiger', email => 'nate@wiger.org');
1717 Will generate SQL like this:
1719 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1721 However, you may want loose comparisons by default, so if you set
1722 C<cmp> to C<like> you would get SQL such as:
1724 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1726 You can also override the comparison on an individual basis - see
1727 the huge section on L</"WHERE CLAUSES"> at the bottom.
1729 =item sqltrue, sqlfalse
1731 Expressions for inserting boolean values within SQL statements.
1732 By default these are C<1=1> and C<1=0>. They are used
1733 by the special operators C<-in> and C<-not_in> for generating
1734 correct SQL even when the argument is an empty array (see below).
1738 This determines the default logical operator for multiple WHERE
1739 statements in arrays or hashes. If absent, the default logic is "or"
1740 for arrays, and "and" for hashes. This means that a WHERE
1744 event_date => {'>=', '2/13/99'},
1745 event_date => {'<=', '4/24/03'},
1748 will generate SQL like this:
1750 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1752 This is probably not what you want given this query, though (look
1753 at the dates). To change the "OR" to an "AND", simply specify:
1755 my $sql = SQL::Abstract->new(logic => 'and');
1757 Which will change the above C<WHERE> to:
1759 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1761 The logic can also be changed locally by inserting
1762 a modifier in front of an arrayref:
1764 @where = (-and => [event_date => {'>=', '2/13/99'},
1765 event_date => {'<=', '4/24/03'} ]);
1767 See the L</"WHERE CLAUSES"> section for explanations.
1771 This will automatically convert comparisons using the specified SQL
1772 function for both column and value. This is mostly used with an argument
1773 of C<upper> or C<lower>, so that the SQL will have the effect of
1774 case-insensitive "searches". For example, this:
1776 $sql = SQL::Abstract->new(convert => 'upper');
1777 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1779 Will turn out the following SQL:
1781 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1783 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1784 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1785 not validate this option; it will just pass through what you specify verbatim).
1789 This is a kludge because many databases suck. For example, you can't
1790 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1791 Instead, you have to use C<bind_param()>:
1793 $sth->bind_param(1, 'reg data');
1794 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1796 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1797 which loses track of which field each slot refers to. Fear not.
1799 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1800 Currently, you can specify either C<normal> (default) or C<columns>. If you
1801 specify C<columns>, you will get an array that looks like this:
1803 my $sql = SQL::Abstract->new(bindtype => 'columns');
1804 my($stmt, @bind) = $sql->insert(...);
1807 [ 'column1', 'value1' ],
1808 [ 'column2', 'value2' ],
1809 [ 'column3', 'value3' ],
1812 You can then iterate through this manually, using DBI's C<bind_param()>.
1814 $sth->prepare($stmt);
1817 my($col, $data) = @$_;
1818 if ($col eq 'details' || $col eq 'comments') {
1819 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1820 } elsif ($col eq 'image') {
1821 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1823 $sth->bind_param($i, $data);
1827 $sth->execute; # execute without @bind now
1829 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1830 Basically, the advantage is still that you don't have to care which fields
1831 are or are not included. You could wrap that above C<for> loop in a simple
1832 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1833 get a layer of abstraction over manual SQL specification.
1835 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1836 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1837 will expect the bind values in this format.
1841 This is the character that a table or column name will be quoted
1842 with. By default this is an empty string, but you could set it to
1843 the character C<`>, to generate SQL like this:
1845 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1847 Alternatively, you can supply an array ref of two items, the first being the left
1848 hand quote character, and the second the right hand quote character. For
1849 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1850 that generates SQL like this:
1852 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1854 Quoting is useful if you have tables or columns names that are reserved
1855 words in your database's SQL dialect.
1859 This is the character that will be used to escape L</quote_char>s appearing
1860 in an identifier before it has been quoted.
1862 The parameter default in case of a single L</quote_char> character is the quote
1865 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1866 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1867 of the B<opening (left)> L</quote_char> within the identifier are currently left
1868 untouched. The default for opening-closing-style quotes may change in future
1869 versions, thus you are B<strongly encouraged> to specify the escape character
1874 This is the character that separates a table and column name. It is
1875 necessary to specify this when the C<quote_char> option is selected,
1876 so that tables and column names can be individually quoted like this:
1878 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1880 =item injection_guard
1882 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1883 column name specified in a query structure. This is a safety mechanism to avoid
1884 injection attacks when mishandling user input e.g.:
1886 my %condition_as_column_value_pairs = get_values_from_user();
1887 $sqla->select( ... , \%condition_as_column_value_pairs );
1889 If the expression matches an exception is thrown. Note that literal SQL
1890 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1892 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1894 =item array_datatypes
1896 When this option is true, arrayrefs in INSERT or UPDATE are
1897 interpreted as array datatypes and are passed directly
1899 When this option is false, arrayrefs are interpreted
1900 as literal SQL, just like refs to arrayrefs
1901 (but this behavior is for backwards compatibility; when writing
1902 new queries, use the "reference to arrayref" syntax
1908 Takes a reference to a list of "special operators"
1909 to extend the syntax understood by L<SQL::Abstract>.
1910 See section L</"SPECIAL OPERATORS"> for details.
1914 Takes a reference to a list of "unary operators"
1915 to extend the syntax understood by L<SQL::Abstract>.
1916 See section L</"UNARY OPERATORS"> for details.
1922 =head2 insert($table, \@values || \%fieldvals, \%options)
1924 This is the simplest function. You simply give it a table name
1925 and either an arrayref of values or hashref of field/value pairs.
1926 It returns an SQL INSERT statement and a list of bind values.
1927 See the sections on L</"Inserting and Updating Arrays"> and
1928 L</"Inserting and Updating SQL"> for information on how to insert
1929 with those data types.
1931 The optional C<\%options> hash reference may contain additional
1932 options to generate the insert SQL. Currently supported options
1939 Takes either a scalar of raw SQL fields, or an array reference of
1940 field names, and adds on an SQL C<RETURNING> statement at the end.
1941 This allows you to return data generated by the insert statement
1942 (such as row IDs) without performing another C<SELECT> statement.
1943 Note, however, this is not part of the SQL standard and may not
1944 be supported by all database engines.
1948 =head2 update($table, \%fieldvals, \%where, \%options)
1950 This takes a table, hashref of field/value pairs, and an optional
1951 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1953 See the sections on L</"Inserting and Updating Arrays"> and
1954 L</"Inserting and Updating SQL"> for information on how to insert
1955 with those data types.
1957 The optional C<\%options> hash reference may contain additional
1958 options to generate the update SQL. Currently supported options
1965 See the C<returning> option to
1966 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1970 =head2 select($source, $fields, $where, $order)
1972 This returns a SQL SELECT statement and associated list of bind values, as
1973 specified by the arguments:
1979 Specification of the 'FROM' part of the statement.
1980 The argument can be either a plain scalar (interpreted as a table
1981 name, will be quoted), or an arrayref (interpreted as a list
1982 of table names, joined by commas, quoted), or a scalarref
1983 (literal SQL, not quoted).
1987 Specification of the list of fields to retrieve from
1989 The argument can be either an arrayref (interpreted as a list
1990 of field names, will be joined by commas and quoted), or a
1991 plain scalar (literal SQL, not quoted).
1992 Please observe that this API is not as flexible as that of
1993 the first argument C<$source>, for backwards compatibility reasons.
1997 Optional argument to specify the WHERE part of the query.
1998 The argument is most often a hashref, but can also be
1999 an arrayref or plain scalar --
2000 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2004 Optional argument to specify the ORDER BY part of the query.
2005 The argument can be a scalar, a hashref or an arrayref
2006 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2012 =head2 delete($table, \%where, \%options)
2014 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2015 It returns an SQL DELETE statement and list of bind values.
2017 The optional C<\%options> hash reference may contain additional
2018 options to generate the delete SQL. Currently supported options
2025 See the C<returning> option to
2026 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2030 =head2 where(\%where, $order)
2032 This is used to generate just the WHERE clause. For example,
2033 if you have an arbitrary data structure and know what the
2034 rest of your SQL is going to look like, but want an easy way
2035 to produce a WHERE clause, use this. It returns an SQL WHERE
2036 clause and list of bind values.
2039 =head2 values(\%data)
2041 This just returns the values from the hash C<%data>, in the same
2042 order that would be returned from any of the other above queries.
2043 Using this allows you to markedly speed up your queries if you
2044 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2046 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2048 Warning: This is an experimental method and subject to change.
2050 This returns arbitrarily generated SQL. It's a really basic shortcut.
2051 It will return two different things, depending on return context:
2053 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2054 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2056 These would return the following:
2058 # First calling form
2059 $stmt = "CREATE TABLE test (?, ?)";
2060 @bind = (field1, field2);
2062 # Second calling form
2063 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2065 Depending on what you're trying to do, it's up to you to choose the correct
2066 format. In this example, the second form is what you would want.
2070 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2074 ALTER SESSION SET nls_date_format = 'MM/YY'
2076 You get the idea. Strings get their case twiddled, but everything
2077 else remains verbatim.
2079 =head1 EXPORTABLE FUNCTIONS
2081 =head2 is_plain_value
2083 Determines if the supplied argument is a plain value as understood by this
2088 =item * The value is C<undef>
2090 =item * The value is a non-reference
2092 =item * The value is an object with stringification overloading
2094 =item * The value is of the form C<< { -value => $anything } >>
2098 On failure returns C<undef>, on success returns a B<scalar> reference
2099 to the original supplied argument.
2105 The stringification overloading detection is rather advanced: it takes
2106 into consideration not only the presence of a C<""> overload, but if that
2107 fails also checks for enabled
2108 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2109 on either C<0+> or C<bool>.
2111 Unfortunately testing in the field indicates that this
2112 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2113 but only when very large numbers of stringifying objects are involved.
2114 At the time of writing ( Sep 2014 ) there is no clear explanation of
2115 the direct cause, nor is there a manageably small test case that reliably
2116 reproduces the problem.
2118 If you encounter any of the following exceptions in B<random places within
2119 your application stack> - this module may be to blame:
2121 Operation "ne": no method found,
2122 left argument in overloaded package <something>,
2123 right argument in overloaded package <something>
2127 Stub found while resolving method "???" overloading """" in package <something>
2129 If you fall victim to the above - please attempt to reduce the problem
2130 to something that could be sent to the L<SQL::Abstract developers
2131 |DBIx::Class/GETTING HELP/SUPPORT>
2132 (either publicly or privately). As a workaround in the meantime you can
2133 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2134 value, which will most likely eliminate your problem (at the expense of
2135 not being able to properly detect exotic forms of stringification).
2137 This notice and environment variable will be removed in a future version,
2138 as soon as the underlying problem is found and a reliable workaround is
2143 =head2 is_literal_value
2145 Determines if the supplied argument is a literal value as understood by this
2150 =item * C<\$sql_string>
2152 =item * C<\[ $sql_string, @bind_values ]>
2156 On failure returns C<undef>, on success returns an B<array> reference
2157 containing the unpacked version of the supplied literal SQL and bind values.
2159 =head1 WHERE CLAUSES
2163 This module uses a variation on the idea from L<DBIx::Abstract>. It
2164 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2165 module is that things in arrays are OR'ed, and things in hashes
2168 The easiest way to explain is to show lots of examples. After
2169 each C<%where> hash shown, it is assumed you used:
2171 my($stmt, @bind) = $sql->where(\%where);
2173 However, note that the C<%where> hash can be used directly in any
2174 of the other functions as well, as described above.
2176 =head2 Key-value pairs
2178 So, let's get started. To begin, a simple hash:
2182 status => 'completed'
2185 Is converted to SQL C<key = val> statements:
2187 $stmt = "WHERE user = ? AND status = ?";
2188 @bind = ('nwiger', 'completed');
2190 One common thing I end up doing is having a list of values that
2191 a field can be in. To do this, simply specify a list inside of
2196 status => ['assigned', 'in-progress', 'pending'];
2199 This simple code will create the following:
2201 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2202 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2204 A field associated to an empty arrayref will be considered a
2205 logical false and will generate 0=1.
2207 =head2 Tests for NULL values
2209 If the value part is C<undef> then this is converted to SQL <IS NULL>
2218 $stmt = "WHERE user = ? AND status IS NULL";
2221 To test if a column IS NOT NULL:
2225 status => { '!=', undef },
2228 =head2 Specific comparison operators
2230 If you want to specify a different type of operator for your comparison,
2231 you can use a hashref for a given column:
2235 status => { '!=', 'completed' }
2238 Which would generate:
2240 $stmt = "WHERE user = ? AND status != ?";
2241 @bind = ('nwiger', 'completed');
2243 To test against multiple values, just enclose the values in an arrayref:
2245 status => { '=', ['assigned', 'in-progress', 'pending'] };
2247 Which would give you:
2249 "WHERE status = ? OR status = ? OR status = ?"
2252 The hashref can also contain multiple pairs, in which case it is expanded
2253 into an C<AND> of its elements:
2257 status => { '!=', 'completed', -not_like => 'pending%' }
2260 # Or more dynamically, like from a form
2261 $where{user} = 'nwiger';
2262 $where{status}{'!='} = 'completed';
2263 $where{status}{'-not_like'} = 'pending%';
2265 # Both generate this
2266 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2267 @bind = ('nwiger', 'completed', 'pending%');
2270 To get an OR instead, you can combine it with the arrayref idea:
2274 priority => [ { '=', 2 }, { '>', 5 } ]
2277 Which would generate:
2279 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2280 @bind = ('2', '5', 'nwiger');
2282 If you want to include literal SQL (with or without bind values), just use a
2283 scalar reference or reference to an arrayref as the value:
2286 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2287 date_expires => { '<' => \"now()" }
2290 Which would generate:
2292 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2293 @bind = ('11/26/2008');
2296 =head2 Logic and nesting operators
2298 In the example above,
2299 there is a subtle trap if you want to say something like
2300 this (notice the C<AND>):
2302 WHERE priority != ? AND priority != ?
2304 Because, in Perl you I<can't> do this:
2306 priority => { '!=' => 2, '!=' => 1 }
2308 As the second C<!=> key will obliterate the first. The solution
2309 is to use the special C<-modifier> form inside an arrayref:
2311 priority => [ -and => {'!=', 2},
2315 Normally, these would be joined by C<OR>, but the modifier tells it
2316 to use C<AND> instead. (Hint: You can use this in conjunction with the
2317 C<logic> option to C<new()> in order to change the way your queries
2318 work by default.) B<Important:> Note that the C<-modifier> goes
2319 B<INSIDE> the arrayref, as an extra first element. This will
2320 B<NOT> do what you think it might:
2322 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2324 Here is a quick list of equivalencies, since there is some overlap:
2327 status => {'!=', 'completed', 'not like', 'pending%' }
2328 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2331 status => {'=', ['assigned', 'in-progress']}
2332 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2333 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2337 =head2 Special operators: IN, BETWEEN, etc.
2339 You can also use the hashref format to compare a list of fields using the
2340 C<IN> comparison operator, by specifying the list as an arrayref:
2343 status => 'completed',
2344 reportid => { -in => [567, 2335, 2] }
2347 Which would generate:
2349 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2350 @bind = ('completed', '567', '2335', '2');
2352 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2355 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2356 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2357 'sqltrue' (by default: C<1=1>).
2359 In addition to the array you can supply a chunk of literal sql or
2360 literal sql with bind:
2363 customer => { -in => \[
2364 'SELECT cust_id FROM cust WHERE balance > ?',
2367 status => { -in => \'SELECT status_codes FROM states' },
2373 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2374 AND status IN ( SELECT status_codes FROM states )
2378 Finally, if the argument to C<-in> is not a reference, it will be
2379 treated as a single-element array.
2381 Another pair of operators is C<-between> and C<-not_between>,
2382 used with an arrayref of two values:
2386 completion_date => {
2387 -not_between => ['2002-10-01', '2003-02-06']
2393 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2395 Just like with C<-in> all plausible combinations of literal SQL
2399 start0 => { -between => [ 1, 2 ] },
2400 start1 => { -between => \["? AND ?", 1, 2] },
2401 start2 => { -between => \"lower(x) AND upper(y)" },
2402 start3 => { -between => [
2404 \["upper(?)", 'stuff' ],
2411 ( start0 BETWEEN ? AND ? )
2412 AND ( start1 BETWEEN ? AND ? )
2413 AND ( start2 BETWEEN lower(x) AND upper(y) )
2414 AND ( start3 BETWEEN lower(x) AND upper(?) )
2416 @bind = (1, 2, 1, 2, 'stuff');
2419 These are the two builtin "special operators"; but the
2420 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2422 =head2 Unary operators: bool
2424 If you wish to test against boolean columns or functions within your
2425 database you can use the C<-bool> and C<-not_bool> operators. For
2426 example to test the column C<is_user> being true and the column
2427 C<is_enabled> being false you would use:-
2431 -not_bool => 'is_enabled',
2436 WHERE is_user AND NOT is_enabled
2438 If a more complex combination is required, testing more conditions,
2439 then you should use the and/or operators:-
2444 -not_bool => { two=> { -rlike => 'bar' } },
2445 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2456 (NOT ( three = ? OR three > ? ))
2459 =head2 Nested conditions, -and/-or prefixes
2461 So far, we've seen how multiple conditions are joined with a top-level
2462 C<AND>. We can change this by putting the different conditions we want in
2463 hashes and then putting those hashes in an array. For example:
2468 status => { -like => ['pending%', 'dispatched'] },
2472 status => 'unassigned',
2476 This data structure would create the following:
2478 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2479 OR ( user = ? AND status = ? ) )";
2480 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2483 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2484 to change the logic inside:
2490 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2491 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2498 $stmt = "WHERE ( user = ?
2499 AND ( ( workhrs > ? AND geo = ? )
2500 OR ( workhrs < ? OR geo = ? ) ) )";
2501 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2503 =head3 Algebraic inconsistency, for historical reasons
2505 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2506 operator goes C<outside> of the nested structure; whereas when connecting
2507 several constraints on one column, the C<-and> operator goes
2508 C<inside> the arrayref. Here is an example combining both features:
2511 -and => [a => 1, b => 2],
2512 -or => [c => 3, d => 4],
2513 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2518 WHERE ( ( ( a = ? AND b = ? )
2519 OR ( c = ? OR d = ? )
2520 OR ( e LIKE ? AND e LIKE ? ) ) )
2522 This difference in syntax is unfortunate but must be preserved for
2523 historical reasons. So be careful: the two examples below would
2524 seem algebraically equivalent, but they are not
2527 { -like => 'foo%' },
2528 { -like => '%bar' },
2530 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2533 { col => { -like => 'foo%' } },
2534 { col => { -like => '%bar' } },
2536 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2539 =head2 Literal SQL and value type operators
2541 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2542 side" is a column name and the "right side" is a value (normally rendered as
2543 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2544 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2545 alter this behavior. There are several ways of doing so.
2549 This is a virtual operator that signals the string to its right side is an
2550 identifier (a column name) and not a value. For example to compare two
2551 columns you would write:
2554 priority => { '<', 2 },
2555 requestor => { -ident => 'submitter' },
2560 $stmt = "WHERE priority < ? AND requestor = submitter";
2563 If you are maintaining legacy code you may see a different construct as
2564 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2569 This is a virtual operator that signals that the construct to its right side
2570 is a value to be passed to DBI. This is for example necessary when you want
2571 to write a where clause against an array (for RDBMS that support such
2572 datatypes). For example:
2575 array => { -value => [1, 2, 3] }
2580 $stmt = 'WHERE array = ?';
2581 @bind = ([1, 2, 3]);
2583 Note that if you were to simply say:
2589 the result would probably not be what you wanted:
2591 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2596 Finally, sometimes only literal SQL will do. To include a random snippet
2597 of SQL verbatim, you specify it as a scalar reference. Consider this only
2598 as a last resort. Usually there is a better way. For example:
2601 priority => { '<', 2 },
2602 requestor => { -in => \'(SELECT name FROM hitmen)' },
2607 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2610 Note that in this example, you only get one bind parameter back, since
2611 the verbatim SQL is passed as part of the statement.
2615 Never use untrusted input as a literal SQL argument - this is a massive
2616 security risk (there is no way to check literal snippets for SQL
2617 injections and other nastyness). If you need to deal with untrusted input
2618 use literal SQL with placeholders as described next.
2620 =head3 Literal SQL with placeholders and bind values (subqueries)
2622 If the literal SQL to be inserted has placeholders and bind values,
2623 use a reference to an arrayref (yes this is a double reference --
2624 not so common, but perfectly legal Perl). For example, to find a date
2625 in Postgres you can use something like this:
2628 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2633 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2636 Note that you must pass the bind values in the same format as they are returned
2637 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2638 to C<columns>, you must provide the bind values in the
2639 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2640 scalar value; most commonly the column name, but you can use any scalar value
2641 (including references and blessed references), L<SQL::Abstract> will simply
2642 pass it through intact. So if C<bindtype> is set to C<columns> the above
2643 example will look like:
2646 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2649 Literal SQL is especially useful for nesting parenthesized clauses in the
2650 main SQL query. Here is a first example:
2652 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2656 bar => \["IN ($sub_stmt)" => @sub_bind],
2661 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2662 WHERE c2 < ? AND c3 LIKE ?))";
2663 @bind = (1234, 100, "foo%");
2665 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2666 are expressed in the same way. Of course the C<$sub_stmt> and
2667 its associated bind values can be generated through a former call
2670 my ($sub_stmt, @sub_bind)
2671 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2672 c3 => {-like => "foo%"}});
2675 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2678 In the examples above, the subquery was used as an operator on a column;
2679 but the same principle also applies for a clause within the main C<%where>
2680 hash, like an EXISTS subquery:
2682 my ($sub_stmt, @sub_bind)
2683 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2684 my %where = ( -and => [
2686 \["EXISTS ($sub_stmt)" => @sub_bind],
2691 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2692 WHERE c1 = ? AND c2 > t0.c0))";
2696 Observe that the condition on C<c2> in the subquery refers to
2697 column C<t0.c0> of the main query: this is I<not> a bind
2698 value, so we have to express it through a scalar ref.
2699 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2700 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2701 what we wanted here.
2703 Finally, here is an example where a subquery is used
2704 for expressing unary negation:
2706 my ($sub_stmt, @sub_bind)
2707 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2708 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2710 lname => {like => '%son%'},
2711 \["NOT ($sub_stmt)" => @sub_bind],
2716 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2717 @bind = ('%son%', 10, 20)
2719 =head3 Deprecated usage of Literal SQL
2721 Below are some examples of archaic use of literal SQL. It is shown only as
2722 reference for those who deal with legacy code. Each example has a much
2723 better, cleaner and safer alternative that users should opt for in new code.
2729 my %where = ( requestor => \'IS NOT NULL' )
2731 $stmt = "WHERE requestor IS NOT NULL"
2733 This used to be the way of generating NULL comparisons, before the handling
2734 of C<undef> got formalized. For new code please use the superior syntax as
2735 described in L</Tests for NULL values>.
2739 my %where = ( requestor => \'= submitter' )
2741 $stmt = "WHERE requestor = submitter"
2743 This used to be the only way to compare columns. Use the superior L</-ident>
2744 method for all new code. For example an identifier declared in such a way
2745 will be properly quoted if L</quote_char> is properly set, while the legacy
2746 form will remain as supplied.
2750 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2752 $stmt = "WHERE completed > ? AND is_ready"
2753 @bind = ('2012-12-21')
2755 Using an empty string literal used to be the only way to express a boolean.
2756 For all new code please use the much more readable
2757 L<-bool|/Unary operators: bool> operator.
2763 These pages could go on for a while, since the nesting of the data
2764 structures this module can handle are pretty much unlimited (the
2765 module implements the C<WHERE> expansion as a recursive function
2766 internally). Your best bet is to "play around" with the module a
2767 little to see how the data structures behave, and choose the best
2768 format for your data based on that.
2770 And of course, all the values above will probably be replaced with
2771 variables gotten from forms or the command line. After all, if you
2772 knew everything ahead of time, you wouldn't have to worry about
2773 dynamically-generating SQL and could just hardwire it into your
2776 =head1 ORDER BY CLAUSES
2778 Some functions take an order by clause. This can either be a scalar (just a
2779 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2780 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2783 Given | Will Generate
2784 ---------------------------------------------------------------
2786 'colA' | ORDER BY colA
2788 [qw/colA colB/] | ORDER BY colA, colB
2790 {-asc => 'colA'} | ORDER BY colA ASC
2792 {-desc => 'colB'} | ORDER BY colB DESC
2794 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2796 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2798 \'colA DESC' | ORDER BY colA DESC
2800 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2801 | /* ...with $x bound to ? */
2804 { -asc => 'colA' }, | colA ASC,
2805 { -desc => [qw/colB/] }, | colB DESC,
2806 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2807 \'colE DESC', | colE DESC,
2808 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2809 ] | /* ...with $x bound to ? */
2810 ===============================================================
2814 =head1 SPECIAL OPERATORS
2816 my $sqlmaker = SQL::Abstract->new(special_ops => [
2820 my ($self, $field, $op, $arg) = @_;
2826 handler => 'method_name',
2830 A "special operator" is a SQL syntactic clause that can be
2831 applied to a field, instead of a usual binary operator.
2834 WHERE field IN (?, ?, ?)
2835 WHERE field BETWEEN ? AND ?
2836 WHERE MATCH(field) AGAINST (?, ?)
2838 Special operators IN and BETWEEN are fairly standard and therefore
2839 are builtin within C<SQL::Abstract> (as the overridable methods
2840 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2841 like the MATCH .. AGAINST example above which is specific to MySQL,
2842 you can write your own operator handlers - supply a C<special_ops>
2843 argument to the C<new> method. That argument takes an arrayref of
2844 operator definitions; each operator definition is a hashref with two
2851 the regular expression to match the operator
2855 Either a coderef or a plain scalar method name. In both cases
2856 the expected return is C<< ($sql, @bind) >>.
2858 When supplied with a method name, it is simply called on the
2859 L<SQL::Abstract> object as:
2861 $self->$method_name($field, $op, $arg)
2865 $field is the LHS of the operator
2866 $op is the part that matched the handler regex
2869 When supplied with a coderef, it is called as:
2871 $coderef->($self, $field, $op, $arg)
2876 For example, here is an implementation
2877 of the MATCH .. AGAINST syntax for MySQL
2879 my $sqlmaker = SQL::Abstract->new(special_ops => [
2881 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2882 {regex => qr/^match$/i,
2884 my ($self, $field, $op, $arg) = @_;
2885 $arg = [$arg] if not ref $arg;
2886 my $label = $self->_quote($field);
2887 my ($placeholder) = $self->_convert('?');
2888 my $placeholders = join ", ", (($placeholder) x @$arg);
2889 my $sql = $self->_sqlcase('match') . " ($label) "
2890 . $self->_sqlcase('against') . " ($placeholders) ";
2891 my @bind = $self->_bindtype($field, @$arg);
2892 return ($sql, @bind);
2899 =head1 UNARY OPERATORS
2901 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2905 my ($self, $op, $arg) = @_;
2911 handler => 'method_name',
2915 A "unary operator" is a SQL syntactic clause that can be
2916 applied to a field - the operator goes before the field
2918 You can write your own operator handlers - supply a C<unary_ops>
2919 argument to the C<new> method. That argument takes an arrayref of
2920 operator definitions; each operator definition is a hashref with two
2927 the regular expression to match the operator
2931 Either a coderef or a plain scalar method name. In both cases
2932 the expected return is C<< $sql >>.
2934 When supplied with a method name, it is simply called on the
2935 L<SQL::Abstract> object as:
2937 $self->$method_name($op, $arg)
2941 $op is the part that matched the handler regex
2942 $arg is the RHS or argument of the operator
2944 When supplied with a coderef, it is called as:
2946 $coderef->($self, $op, $arg)
2954 Thanks to some benchmarking by Mark Stosberg, it turns out that
2955 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2956 I must admit this wasn't an intentional design issue, but it's a
2957 byproduct of the fact that you get to control your C<DBI> handles
2960 To maximize performance, use a code snippet like the following:
2962 # prepare a statement handle using the first row
2963 # and then reuse it for the rest of the rows
2965 for my $href (@array_of_hashrefs) {
2966 $stmt ||= $sql->insert('table', $href);
2967 $sth ||= $dbh->prepare($stmt);
2968 $sth->execute($sql->values($href));
2971 The reason this works is because the keys in your C<$href> are sorted
2972 internally by B<SQL::Abstract>. Thus, as long as your data retains
2973 the same structure, you only have to generate the SQL the first time
2974 around. On subsequent queries, simply use the C<values> function provided
2975 by this module to return your values in the correct order.
2977 However this depends on the values having the same type - if, for
2978 example, the values of a where clause may either have values
2979 (resulting in sql of the form C<column = ?> with a single bind
2980 value), or alternatively the values might be C<undef> (resulting in
2981 sql of the form C<column IS NULL> with no bind value) then the
2982 caching technique suggested will not work.
2986 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2987 really like this part (I do, at least). Building up a complex query
2988 can be as simple as the following:
2995 use CGI::FormBuilder;
2998 my $form = CGI::FormBuilder->new(...);
2999 my $sql = SQL::Abstract->new;
3001 if ($form->submitted) {
3002 my $field = $form->field;
3003 my $id = delete $field->{id};
3004 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3007 Of course, you would still have to connect using C<DBI> to run the
3008 query, but the point is that if you make your form look like your
3009 table, the actual query script can be extremely simplistic.
3011 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3012 a fast interface to returning and formatting data. I frequently
3013 use these three modules together to write complex database query
3014 apps in under 50 lines.
3016 =head1 HOW TO CONTRIBUTE
3018 Contributions are always welcome, in all usable forms (we especially
3019 welcome documentation improvements). The delivery methods include git-
3020 or unified-diff formatted patches, GitHub pull requests, or plain bug
3021 reports either via RT or the Mailing list. Contributors are generally
3022 granted full access to the official repository after their first several
3023 patches pass successful review.
3025 This project is maintained in a git repository. The code and related tools are
3026 accessible at the following locations:
3030 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3032 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3034 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3036 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3042 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3043 Great care has been taken to preserve the I<published> behavior
3044 documented in previous versions in the 1.* family; however,
3045 some features that were previously undocumented, or behaved
3046 differently from the documentation, had to be changed in order
3047 to clarify the semantics. Hence, client code that was relying
3048 on some dark areas of C<SQL::Abstract> v1.*
3049 B<might behave differently> in v1.50.
3051 The main changes are:
3057 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3061 support for the { operator => \"..." } construct (to embed literal SQL)
3065 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3069 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3073 defensive programming: check arguments
3077 fixed bug with global logic, which was previously implemented
3078 through global variables yielding side-effects. Prior versions would
3079 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3080 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3081 Now this is interpreted
3082 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3087 fixed semantics of _bindtype on array args
3091 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3092 we just avoid shifting arrays within that tree.
3096 dropped the C<_modlogic> function
3100 =head1 ACKNOWLEDGEMENTS
3102 There are a number of individuals that have really helped out with
3103 this module. Unfortunately, most of them submitted bugs via CPAN
3104 so I have no idea who they are! But the people I do know are:
3106 Ash Berlin (order_by hash term support)
3107 Matt Trout (DBIx::Class support)
3108 Mark Stosberg (benchmarking)
3109 Chas Owens (initial "IN" operator support)
3110 Philip Collins (per-field SQL functions)
3111 Eric Kolve (hashref "AND" support)
3112 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3113 Dan Kubb (support for "quote_char" and "name_sep")
3114 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3115 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3116 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3117 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3118 Oliver Charles (support for "RETURNING" after "INSERT")
3124 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3128 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3130 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3132 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3133 While not an official support venue, C<DBIx::Class> makes heavy use of
3134 C<SQL::Abstract>, and as such list members there are very familiar with
3135 how to create queries.
3139 This module is free software; you may copy this under the same
3140 terms as perl itself (either the GNU General Public License or
3141 the Artistic License)