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 = '1.86';
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',
1031 my ($self, $op, $args) = @_;
1032 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$args;
1033 return '' unless @parts;
1034 return @{$parts[0]} if @parts == 1;
1035 my ($final_sql) = join(
1036 ' '.$self->_sqlcase($op).' ',
1041 map @{$_}[1..$#$_], @parts
1047 my ($self, $v) = @_;
1048 my ($op, @args) = @$v;
1049 if (my $r = $self->{render_op}{$op}) {
1050 return $self->$r($op, \@args);
1052 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1053 if ($us and @args > 1) {
1054 puke "Special op '${op}' requires first value to be identifier"
1055 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1056 my $k = join(($self->{name_sep}||'.'), @$ident);
1057 local our $Expand_Depth = 1;
1058 return $self->${\($us->{handler})}($k, $op, $args[1]);
1060 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1061 return $self->${\($us->{handler})}($op, $args[0]);
1064 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1065 my $op_sql = $self->_sqlcase($op);
1066 my $final_sql = "${op_sql} ${expr_sql}";
1067 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1069 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1070 return '' unless @parts;
1071 my ($final_sql) = join(
1072 ' '.$self->_sqlcase($op).' ',
1077 map @{$_}[1..$#$_], @parts
1083 sub _render_unop_postfix {
1084 my ($self, $op, $v) = @_;
1085 my ($arg, @argh) = @$v;
1086 puke "Argh" if @argh;
1087 my ($expr_sql, @bind) = $self->render_aqt($arg);
1088 my $op_sql = $self->_sqlcase($op);
1089 return ($expr_sql.' '.$op_sql, @bind);
1092 # Some databases (SQLite) treat col IN (1, 2) different from
1093 # col IN ( (1, 2) ). Use this to strip all outer parens while
1094 # adding them back in the corresponding method
1095 sub _open_outer_paren {
1096 my ($self, $sql) = @_;
1098 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1100 # there are closing parens inside, need the heavy duty machinery
1101 # to reevaluate the extraction starting from $sql (full reevaluation)
1102 if ($inner =~ /\)/) {
1103 require Text::Balanced;
1105 my (undef, $remainder) = do {
1106 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1108 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1111 # the entire expression needs to be a balanced bracketed thing
1112 # (after an extract no remainder sans trailing space)
1113 last if defined $remainder and $remainder =~ /\S/;
1123 #======================================================================
1125 #======================================================================
1127 sub _expand_order_by {
1128 my ($self, $arg) = @_;
1130 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1132 my $expander = sub {
1133 my ($self, $dir, $expr) = @_;
1134 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1135 foreach my $arg (@to_expand) {
1139 and grep /^-(asc|desc)$/, keys %$arg
1141 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1145 defined($dir) ? { -op => [ $dir =~ /^-?(.*)$/ ,=> $_ ] } : $_
1147 map $self->expand_expr($_, -ident),
1148 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1149 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1152 local @{$self->{expand}}{qw(-asc -desc)} = (($expander) x 2);
1154 return $self->$expander(undef, $arg);
1158 my ($self, $arg) = @_;
1160 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1162 my ($sql, @bind) = $self->render_aqt($expanded);
1164 return '' unless length($sql);
1166 my $final_sql = $self->_sqlcase(' order by ').$sql;
1168 return wantarray ? ($final_sql, @bind) : $final_sql;
1171 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1173 sub _order_by_chunks {
1174 my ($self, $arg) = @_;
1176 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1178 return $self->_chunkify_order_by($expanded);
1181 sub _chunkify_order_by {
1182 my ($self, $expanded) = @_;
1184 return grep length, $self->render_aqt($expanded)
1185 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1188 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1189 return map $self->_chunkify_order_by($_), @$l;
1191 return [ $self->render_aqt($_) ];
1195 #======================================================================
1196 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1197 #======================================================================
1203 $self->_expand_maybe_list_expr($from, undef, -ident)
1208 #======================================================================
1210 #======================================================================
1212 sub _expand_maybe_list_expr {
1213 my ($self, $expr, $logic, $default) = @_;
1215 if (ref($expr) eq 'ARRAY') {
1217 map $self->expand_expr($_, $default), @$expr
1224 return $self->expand_expr($e, $default);
1227 # highly optimized, as it's called way too often
1229 # my ($self, $label) = @_;
1231 return '' unless defined $_[1];
1232 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1233 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1235 unless ($_[0]->{quote_char}) {
1236 if (ref($_[1]) eq 'ARRAY') {
1237 return join($_[0]->{name_sep}||'.', @{$_[1]});
1239 $_[0]->_assert_pass_injection_guard($_[1]);
1244 my $qref = ref $_[0]->{quote_char};
1246 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1247 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1248 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1250 my $esc = $_[0]->{escape_char} || $r;
1252 # parts containing * are naturally unquoted
1254 $_[0]->{name_sep}||'',
1258 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1260 (ref($_[1]) eq 'ARRAY'
1264 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1272 # Conversion, if applicable
1274 #my ($self, $arg) = @_;
1275 if ($_[0]->{convert_where}) {
1276 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1283 #my ($self, $col, @vals) = @_;
1284 # called often - tighten code
1285 return $_[0]->{bindtype} eq 'columns'
1286 ? map {[$_[1], $_]} @_[2 .. $#_]
1291 # Dies if any element of @bind is not in [colname => value] format
1292 # if bindtype is 'columns'.
1293 sub _assert_bindval_matches_bindtype {
1294 # my ($self, @bind) = @_;
1296 if ($self->{bindtype} eq 'columns') {
1298 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1299 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1305 sub _join_sql_clauses {
1306 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1308 if (@$clauses_aref > 1) {
1309 my $join = " " . $self->_sqlcase($logic) . " ";
1310 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1311 return ($sql, @$bind_aref);
1313 elsif (@$clauses_aref) {
1314 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1317 return (); # if no SQL, ignore @$bind_aref
1322 # Fix SQL case, if so requested
1324 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1325 # don't touch the argument ... crooked logic, but let's not change it!
1326 return $_[0]->{case} ? $_[1] : uc($_[1]);
1330 #======================================================================
1331 # DISPATCHING FROM REFKIND
1332 #======================================================================
1335 my ($self, $data) = @_;
1337 return 'UNDEF' unless defined $data;
1339 # blessed objects are treated like scalars
1340 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1342 return 'SCALAR' unless $ref;
1345 while ($ref eq 'REF') {
1347 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1351 return ($ref||'SCALAR') . ('REF' x $n_steps);
1355 my ($self, $data) = @_;
1356 my @try = ($self->_refkind($data));
1357 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1358 push @try, 'FALLBACK';
1362 sub _METHOD_FOR_refkind {
1363 my ($self, $meth_prefix, $data) = @_;
1366 for (@{$self->_try_refkind($data)}) {
1367 $method = $self->can($meth_prefix."_".$_)
1371 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1375 sub _SWITCH_refkind {
1376 my ($self, $data, $dispatch_table) = @_;
1379 for (@{$self->_try_refkind($data)}) {
1380 $coderef = $dispatch_table->{$_}
1384 puke "no dispatch entry for ".$self->_refkind($data)
1393 #======================================================================
1394 # VALUES, GENERATE, AUTOLOAD
1395 #======================================================================
1397 # LDNOTE: original code from nwiger, didn't touch code in that section
1398 # I feel the AUTOLOAD stuff should not be the default, it should
1399 # only be activated on explicit demand by user.
1403 my $data = shift || return;
1404 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1405 unless ref $data eq 'HASH';
1408 foreach my $k (sort keys %$data) {
1409 my $v = $data->{$k};
1410 $self->_SWITCH_refkind($v, {
1412 if ($self->{array_datatypes}) { # array datatype
1413 push @all_bind, $self->_bindtype($k, $v);
1415 else { # literal SQL with bind
1416 my ($sql, @bind) = @$v;
1417 $self->_assert_bindval_matches_bindtype(@bind);
1418 push @all_bind, @bind;
1421 ARRAYREFREF => sub { # literal SQL with bind
1422 my ($sql, @bind) = @${$v};
1423 $self->_assert_bindval_matches_bindtype(@bind);
1424 push @all_bind, @bind;
1426 SCALARREF => sub { # literal SQL without bind
1428 SCALAR_or_UNDEF => sub {
1429 push @all_bind, $self->_bindtype($k, $v);
1440 my(@sql, @sqlq, @sqlv);
1444 if ($ref eq 'HASH') {
1445 for my $k (sort keys %$_) {
1448 my $label = $self->_quote($k);
1449 if ($r eq 'ARRAY') {
1450 # literal SQL with bind
1451 my ($sql, @bind) = @$v;
1452 $self->_assert_bindval_matches_bindtype(@bind);
1453 push @sqlq, "$label = $sql";
1455 } elsif ($r eq 'SCALAR') {
1456 # literal SQL without bind
1457 push @sqlq, "$label = $$v";
1459 push @sqlq, "$label = ?";
1460 push @sqlv, $self->_bindtype($k, $v);
1463 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1464 } elsif ($ref eq 'ARRAY') {
1465 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1468 if ($r eq 'ARRAY') { # literal SQL with bind
1469 my ($sql, @bind) = @$v;
1470 $self->_assert_bindval_matches_bindtype(@bind);
1473 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1474 # embedded literal SQL
1481 push @sql, '(' . join(', ', @sqlq) . ')';
1482 } elsif ($ref eq 'SCALAR') {
1486 # strings get case twiddled
1487 push @sql, $self->_sqlcase($_);
1491 my $sql = join ' ', @sql;
1493 # this is pretty tricky
1494 # if ask for an array, return ($stmt, @bind)
1495 # otherwise, s/?/shift @sqlv/ to put it inline
1497 return ($sql, @sqlv);
1499 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1500 ref $d ? $d->[1] : $d/e;
1509 # This allows us to check for a local, then _form, attr
1511 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1512 return $self->generate($name, @_);
1523 SQL::Abstract - Generate SQL from Perl data structures
1529 my $sql = SQL::Abstract->new;
1531 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1533 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1535 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1537 my($stmt, @bind) = $sql->delete($table, \%where);
1539 # Then, use these in your DBI statements
1540 my $sth = $dbh->prepare($stmt);
1541 $sth->execute(@bind);
1543 # Just generate the WHERE clause
1544 my($stmt, @bind) = $sql->where(\%where, $order);
1546 # Return values in the same order, for hashed queries
1547 # See PERFORMANCE section for more details
1548 my @bind = $sql->values(\%fieldvals);
1552 This module was inspired by the excellent L<DBIx::Abstract>.
1553 However, in using that module I found that what I really wanted
1554 to do was generate SQL, but still retain complete control over my
1555 statement handles and use the DBI interface. So, I set out to
1556 create an abstract SQL generation module.
1558 While based on the concepts used by L<DBIx::Abstract>, there are
1559 several important differences, especially when it comes to WHERE
1560 clauses. I have modified the concepts used to make the SQL easier
1561 to generate from Perl data structures and, IMO, more intuitive.
1562 The underlying idea is for this module to do what you mean, based
1563 on the data structures you provide it. The big advantage is that
1564 you don't have to modify your code every time your data changes,
1565 as this module figures it out.
1567 To begin with, an SQL INSERT is as easy as just specifying a hash
1568 of C<key=value> pairs:
1571 name => 'Jimbo Bobson',
1572 phone => '123-456-7890',
1573 address => '42 Sister Lane',
1574 city => 'St. Louis',
1575 state => 'Louisiana',
1578 The SQL can then be generated with this:
1580 my($stmt, @bind) = $sql->insert('people', \%data);
1582 Which would give you something like this:
1584 $stmt = "INSERT INTO people
1585 (address, city, name, phone, state)
1586 VALUES (?, ?, ?, ?, ?)";
1587 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1588 '123-456-7890', 'Louisiana');
1590 These are then used directly in your DBI code:
1592 my $sth = $dbh->prepare($stmt);
1593 $sth->execute(@bind);
1595 =head2 Inserting and Updating Arrays
1597 If your database has array types (like for example Postgres),
1598 activate the special option C<< array_datatypes => 1 >>
1599 when creating the C<SQL::Abstract> object.
1600 Then you may use an arrayref to insert and update database array types:
1602 my $sql = SQL::Abstract->new(array_datatypes => 1);
1604 planets => [qw/Mercury Venus Earth Mars/]
1607 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1611 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1613 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1616 =head2 Inserting and Updating SQL
1618 In order to apply SQL functions to elements of your C<%data> you may
1619 specify a reference to an arrayref for the given hash value. For example,
1620 if you need to execute the Oracle C<to_date> function on a value, you can
1621 say something like this:
1625 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1628 The first value in the array is the actual SQL. Any other values are
1629 optional and would be included in the bind values array. This gives
1632 my($stmt, @bind) = $sql->insert('people', \%data);
1634 $stmt = "INSERT INTO people (name, date_entered)
1635 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1636 @bind = ('Bill', '03/02/2003');
1638 An UPDATE is just as easy, all you change is the name of the function:
1640 my($stmt, @bind) = $sql->update('people', \%data);
1642 Notice that your C<%data> isn't touched; the module will generate
1643 the appropriately quirky SQL for you automatically. Usually you'll
1644 want to specify a WHERE clause for your UPDATE, though, which is
1645 where handling C<%where> hashes comes in handy...
1647 =head2 Complex where statements
1649 This module can generate pretty complicated WHERE statements
1650 easily. For example, simple C<key=value> pairs are taken to mean
1651 equality, and if you want to see if a field is within a set
1652 of values, you can use an arrayref. Let's say we wanted to
1653 SELECT some data based on this criteria:
1656 requestor => 'inna',
1657 worker => ['nwiger', 'rcwe', 'sfz'],
1658 status => { '!=', 'completed' }
1661 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1663 The above would give you something like this:
1665 $stmt = "SELECT * FROM tickets WHERE
1666 ( requestor = ? ) AND ( status != ? )
1667 AND ( worker = ? OR worker = ? OR worker = ? )";
1668 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1670 Which you could then use in DBI code like so:
1672 my $sth = $dbh->prepare($stmt);
1673 $sth->execute(@bind);
1679 The methods are simple. There's one for every major SQL operation,
1680 and a constructor you use first. The arguments are specified in a
1681 similar order for each method (table, then fields, then a where
1682 clause) to try and simplify things.
1684 =head2 new(option => 'value')
1686 The C<new()> function takes a list of options and values, and returns
1687 a new B<SQL::Abstract> object which can then be used to generate SQL
1688 through the methods below. The options accepted are:
1694 If set to 'lower', then SQL will be generated in all lowercase. By
1695 default SQL is generated in "textbook" case meaning something like:
1697 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1699 Any setting other than 'lower' is ignored.
1703 This determines what the default comparison operator is. By default
1704 it is C<=>, meaning that a hash like this:
1706 %where = (name => 'nwiger', email => 'nate@wiger.org');
1708 Will generate SQL like this:
1710 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1712 However, you may want loose comparisons by default, so if you set
1713 C<cmp> to C<like> you would get SQL such as:
1715 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1717 You can also override the comparison on an individual basis - see
1718 the huge section on L</"WHERE CLAUSES"> at the bottom.
1720 =item sqltrue, sqlfalse
1722 Expressions for inserting boolean values within SQL statements.
1723 By default these are C<1=1> and C<1=0>. They are used
1724 by the special operators C<-in> and C<-not_in> for generating
1725 correct SQL even when the argument is an empty array (see below).
1729 This determines the default logical operator for multiple WHERE
1730 statements in arrays or hashes. If absent, the default logic is "or"
1731 for arrays, and "and" for hashes. This means that a WHERE
1735 event_date => {'>=', '2/13/99'},
1736 event_date => {'<=', '4/24/03'},
1739 will generate SQL like this:
1741 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1743 This is probably not what you want given this query, though (look
1744 at the dates). To change the "OR" to an "AND", simply specify:
1746 my $sql = SQL::Abstract->new(logic => 'and');
1748 Which will change the above C<WHERE> to:
1750 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1752 The logic can also be changed locally by inserting
1753 a modifier in front of an arrayref:
1755 @where = (-and => [event_date => {'>=', '2/13/99'},
1756 event_date => {'<=', '4/24/03'} ]);
1758 See the L</"WHERE CLAUSES"> section for explanations.
1762 This will automatically convert comparisons using the specified SQL
1763 function for both column and value. This is mostly used with an argument
1764 of C<upper> or C<lower>, so that the SQL will have the effect of
1765 case-insensitive "searches". For example, this:
1767 $sql = SQL::Abstract->new(convert => 'upper');
1768 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1770 Will turn out the following SQL:
1772 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1774 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1775 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1776 not validate this option; it will just pass through what you specify verbatim).
1780 This is a kludge because many databases suck. For example, you can't
1781 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1782 Instead, you have to use C<bind_param()>:
1784 $sth->bind_param(1, 'reg data');
1785 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1787 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1788 which loses track of which field each slot refers to. Fear not.
1790 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1791 Currently, you can specify either C<normal> (default) or C<columns>. If you
1792 specify C<columns>, you will get an array that looks like this:
1794 my $sql = SQL::Abstract->new(bindtype => 'columns');
1795 my($stmt, @bind) = $sql->insert(...);
1798 [ 'column1', 'value1' ],
1799 [ 'column2', 'value2' ],
1800 [ 'column3', 'value3' ],
1803 You can then iterate through this manually, using DBI's C<bind_param()>.
1805 $sth->prepare($stmt);
1808 my($col, $data) = @$_;
1809 if ($col eq 'details' || $col eq 'comments') {
1810 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1811 } elsif ($col eq 'image') {
1812 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1814 $sth->bind_param($i, $data);
1818 $sth->execute; # execute without @bind now
1820 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1821 Basically, the advantage is still that you don't have to care which fields
1822 are or are not included. You could wrap that above C<for> loop in a simple
1823 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1824 get a layer of abstraction over manual SQL specification.
1826 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1827 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1828 will expect the bind values in this format.
1832 This is the character that a table or column name will be quoted
1833 with. By default this is an empty string, but you could set it to
1834 the character C<`>, to generate SQL like this:
1836 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1838 Alternatively, you can supply an array ref of two items, the first being the left
1839 hand quote character, and the second the right hand quote character. For
1840 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1841 that generates SQL like this:
1843 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1845 Quoting is useful if you have tables or columns names that are reserved
1846 words in your database's SQL dialect.
1850 This is the character that will be used to escape L</quote_char>s appearing
1851 in an identifier before it has been quoted.
1853 The parameter default in case of a single L</quote_char> character is the quote
1856 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1857 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1858 of the B<opening (left)> L</quote_char> within the identifier are currently left
1859 untouched. The default for opening-closing-style quotes may change in future
1860 versions, thus you are B<strongly encouraged> to specify the escape character
1865 This is the character that separates a table and column name. It is
1866 necessary to specify this when the C<quote_char> option is selected,
1867 so that tables and column names can be individually quoted like this:
1869 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1871 =item injection_guard
1873 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1874 column name specified in a query structure. This is a safety mechanism to avoid
1875 injection attacks when mishandling user input e.g.:
1877 my %condition_as_column_value_pairs = get_values_from_user();
1878 $sqla->select( ... , \%condition_as_column_value_pairs );
1880 If the expression matches an exception is thrown. Note that literal SQL
1881 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1883 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1885 =item array_datatypes
1887 When this option is true, arrayrefs in INSERT or UPDATE are
1888 interpreted as array datatypes and are passed directly
1890 When this option is false, arrayrefs are interpreted
1891 as literal SQL, just like refs to arrayrefs
1892 (but this behavior is for backwards compatibility; when writing
1893 new queries, use the "reference to arrayref" syntax
1899 Takes a reference to a list of "special operators"
1900 to extend the syntax understood by L<SQL::Abstract>.
1901 See section L</"SPECIAL OPERATORS"> for details.
1905 Takes a reference to a list of "unary operators"
1906 to extend the syntax understood by L<SQL::Abstract>.
1907 See section L</"UNARY OPERATORS"> for details.
1913 =head2 insert($table, \@values || \%fieldvals, \%options)
1915 This is the simplest function. You simply give it a table name
1916 and either an arrayref of values or hashref of field/value pairs.
1917 It returns an SQL INSERT statement and a list of bind values.
1918 See the sections on L</"Inserting and Updating Arrays"> and
1919 L</"Inserting and Updating SQL"> for information on how to insert
1920 with those data types.
1922 The optional C<\%options> hash reference may contain additional
1923 options to generate the insert SQL. Currently supported options
1930 Takes either a scalar of raw SQL fields, or an array reference of
1931 field names, and adds on an SQL C<RETURNING> statement at the end.
1932 This allows you to return data generated by the insert statement
1933 (such as row IDs) without performing another C<SELECT> statement.
1934 Note, however, this is not part of the SQL standard and may not
1935 be supported by all database engines.
1939 =head2 update($table, \%fieldvals, \%where, \%options)
1941 This takes a table, hashref of field/value pairs, and an optional
1942 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1944 See the sections on L</"Inserting and Updating Arrays"> and
1945 L</"Inserting and Updating SQL"> for information on how to insert
1946 with those data types.
1948 The optional C<\%options> hash reference may contain additional
1949 options to generate the update SQL. Currently supported options
1956 See the C<returning> option to
1957 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1961 =head2 select($source, $fields, $where, $order)
1963 This returns a SQL SELECT statement and associated list of bind values, as
1964 specified by the arguments:
1970 Specification of the 'FROM' part of the statement.
1971 The argument can be either a plain scalar (interpreted as a table
1972 name, will be quoted), or an arrayref (interpreted as a list
1973 of table names, joined by commas, quoted), or a scalarref
1974 (literal SQL, not quoted).
1978 Specification of the list of fields to retrieve from
1980 The argument can be either an arrayref (interpreted as a list
1981 of field names, will be joined by commas and quoted), or a
1982 plain scalar (literal SQL, not quoted).
1983 Please observe that this API is not as flexible as that of
1984 the first argument C<$source>, for backwards compatibility reasons.
1988 Optional argument to specify the WHERE part of the query.
1989 The argument is most often a hashref, but can also be
1990 an arrayref or plain scalar --
1991 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1995 Optional argument to specify the ORDER BY part of the query.
1996 The argument can be a scalar, a hashref or an arrayref
1997 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2003 =head2 delete($table, \%where, \%options)
2005 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2006 It returns an SQL DELETE statement and list of bind values.
2008 The optional C<\%options> hash reference may contain additional
2009 options to generate the delete SQL. Currently supported options
2016 See the C<returning> option to
2017 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2021 =head2 where(\%where, $order)
2023 This is used to generate just the WHERE clause. For example,
2024 if you have an arbitrary data structure and know what the
2025 rest of your SQL is going to look like, but want an easy way
2026 to produce a WHERE clause, use this. It returns an SQL WHERE
2027 clause and list of bind values.
2030 =head2 values(\%data)
2032 This just returns the values from the hash C<%data>, in the same
2033 order that would be returned from any of the other above queries.
2034 Using this allows you to markedly speed up your queries if you
2035 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2037 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2039 Warning: This is an experimental method and subject to change.
2041 This returns arbitrarily generated SQL. It's a really basic shortcut.
2042 It will return two different things, depending on return context:
2044 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2045 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2047 These would return the following:
2049 # First calling form
2050 $stmt = "CREATE TABLE test (?, ?)";
2051 @bind = (field1, field2);
2053 # Second calling form
2054 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2056 Depending on what you're trying to do, it's up to you to choose the correct
2057 format. In this example, the second form is what you would want.
2061 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2065 ALTER SESSION SET nls_date_format = 'MM/YY'
2067 You get the idea. Strings get their case twiddled, but everything
2068 else remains verbatim.
2070 =head1 EXPORTABLE FUNCTIONS
2072 =head2 is_plain_value
2074 Determines if the supplied argument is a plain value as understood by this
2079 =item * The value is C<undef>
2081 =item * The value is a non-reference
2083 =item * The value is an object with stringification overloading
2085 =item * The value is of the form C<< { -value => $anything } >>
2089 On failure returns C<undef>, on success returns a B<scalar> reference
2090 to the original supplied argument.
2096 The stringification overloading detection is rather advanced: it takes
2097 into consideration not only the presence of a C<""> overload, but if that
2098 fails also checks for enabled
2099 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2100 on either C<0+> or C<bool>.
2102 Unfortunately testing in the field indicates that this
2103 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2104 but only when very large numbers of stringifying objects are involved.
2105 At the time of writing ( Sep 2014 ) there is no clear explanation of
2106 the direct cause, nor is there a manageably small test case that reliably
2107 reproduces the problem.
2109 If you encounter any of the following exceptions in B<random places within
2110 your application stack> - this module may be to blame:
2112 Operation "ne": no method found,
2113 left argument in overloaded package <something>,
2114 right argument in overloaded package <something>
2118 Stub found while resolving method "???" overloading """" in package <something>
2120 If you fall victim to the above - please attempt to reduce the problem
2121 to something that could be sent to the L<SQL::Abstract developers
2122 |DBIx::Class/GETTING HELP/SUPPORT>
2123 (either publicly or privately). As a workaround in the meantime you can
2124 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2125 value, which will most likely eliminate your problem (at the expense of
2126 not being able to properly detect exotic forms of stringification).
2128 This notice and environment variable will be removed in a future version,
2129 as soon as the underlying problem is found and a reliable workaround is
2134 =head2 is_literal_value
2136 Determines if the supplied argument is a literal value as understood by this
2141 =item * C<\$sql_string>
2143 =item * C<\[ $sql_string, @bind_values ]>
2147 On failure returns C<undef>, on success returns an B<array> reference
2148 containing the unpacked version of the supplied literal SQL and bind values.
2150 =head1 WHERE CLAUSES
2154 This module uses a variation on the idea from L<DBIx::Abstract>. It
2155 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2156 module is that things in arrays are OR'ed, and things in hashes
2159 The easiest way to explain is to show lots of examples. After
2160 each C<%where> hash shown, it is assumed you used:
2162 my($stmt, @bind) = $sql->where(\%where);
2164 However, note that the C<%where> hash can be used directly in any
2165 of the other functions as well, as described above.
2167 =head2 Key-value pairs
2169 So, let's get started. To begin, a simple hash:
2173 status => 'completed'
2176 Is converted to SQL C<key = val> statements:
2178 $stmt = "WHERE user = ? AND status = ?";
2179 @bind = ('nwiger', 'completed');
2181 One common thing I end up doing is having a list of values that
2182 a field can be in. To do this, simply specify a list inside of
2187 status => ['assigned', 'in-progress', 'pending'];
2190 This simple code will create the following:
2192 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2193 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2195 A field associated to an empty arrayref will be considered a
2196 logical false and will generate 0=1.
2198 =head2 Tests for NULL values
2200 If the value part is C<undef> then this is converted to SQL <IS NULL>
2209 $stmt = "WHERE user = ? AND status IS NULL";
2212 To test if a column IS NOT NULL:
2216 status => { '!=', undef },
2219 =head2 Specific comparison operators
2221 If you want to specify a different type of operator for your comparison,
2222 you can use a hashref for a given column:
2226 status => { '!=', 'completed' }
2229 Which would generate:
2231 $stmt = "WHERE user = ? AND status != ?";
2232 @bind = ('nwiger', 'completed');
2234 To test against multiple values, just enclose the values in an arrayref:
2236 status => { '=', ['assigned', 'in-progress', 'pending'] };
2238 Which would give you:
2240 "WHERE status = ? OR status = ? OR status = ?"
2243 The hashref can also contain multiple pairs, in which case it is expanded
2244 into an C<AND> of its elements:
2248 status => { '!=', 'completed', -not_like => 'pending%' }
2251 # Or more dynamically, like from a form
2252 $where{user} = 'nwiger';
2253 $where{status}{'!='} = 'completed';
2254 $where{status}{'-not_like'} = 'pending%';
2256 # Both generate this
2257 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2258 @bind = ('nwiger', 'completed', 'pending%');
2261 To get an OR instead, you can combine it with the arrayref idea:
2265 priority => [ { '=', 2 }, { '>', 5 } ]
2268 Which would generate:
2270 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2271 @bind = ('2', '5', 'nwiger');
2273 If you want to include literal SQL (with or without bind values), just use a
2274 scalar reference or reference to an arrayref as the value:
2277 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2278 date_expires => { '<' => \"now()" }
2281 Which would generate:
2283 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2284 @bind = ('11/26/2008');
2287 =head2 Logic and nesting operators
2289 In the example above,
2290 there is a subtle trap if you want to say something like
2291 this (notice the C<AND>):
2293 WHERE priority != ? AND priority != ?
2295 Because, in Perl you I<can't> do this:
2297 priority => { '!=' => 2, '!=' => 1 }
2299 As the second C<!=> key will obliterate the first. The solution
2300 is to use the special C<-modifier> form inside an arrayref:
2302 priority => [ -and => {'!=', 2},
2306 Normally, these would be joined by C<OR>, but the modifier tells it
2307 to use C<AND> instead. (Hint: You can use this in conjunction with the
2308 C<logic> option to C<new()> in order to change the way your queries
2309 work by default.) B<Important:> Note that the C<-modifier> goes
2310 B<INSIDE> the arrayref, as an extra first element. This will
2311 B<NOT> do what you think it might:
2313 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2315 Here is a quick list of equivalencies, since there is some overlap:
2318 status => {'!=', 'completed', 'not like', 'pending%' }
2319 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2322 status => {'=', ['assigned', 'in-progress']}
2323 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2324 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2328 =head2 Special operators: IN, BETWEEN, etc.
2330 You can also use the hashref format to compare a list of fields using the
2331 C<IN> comparison operator, by specifying the list as an arrayref:
2334 status => 'completed',
2335 reportid => { -in => [567, 2335, 2] }
2338 Which would generate:
2340 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2341 @bind = ('completed', '567', '2335', '2');
2343 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2346 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2347 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2348 'sqltrue' (by default: C<1=1>).
2350 In addition to the array you can supply a chunk of literal sql or
2351 literal sql with bind:
2354 customer => { -in => \[
2355 'SELECT cust_id FROM cust WHERE balance > ?',
2358 status => { -in => \'SELECT status_codes FROM states' },
2364 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2365 AND status IN ( SELECT status_codes FROM states )
2369 Finally, if the argument to C<-in> is not a reference, it will be
2370 treated as a single-element array.
2372 Another pair of operators is C<-between> and C<-not_between>,
2373 used with an arrayref of two values:
2377 completion_date => {
2378 -not_between => ['2002-10-01', '2003-02-06']
2384 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2386 Just like with C<-in> all plausible combinations of literal SQL
2390 start0 => { -between => [ 1, 2 ] },
2391 start1 => { -between => \["? AND ?", 1, 2] },
2392 start2 => { -between => \"lower(x) AND upper(y)" },
2393 start3 => { -between => [
2395 \["upper(?)", 'stuff' ],
2402 ( start0 BETWEEN ? AND ? )
2403 AND ( start1 BETWEEN ? AND ? )
2404 AND ( start2 BETWEEN lower(x) AND upper(y) )
2405 AND ( start3 BETWEEN lower(x) AND upper(?) )
2407 @bind = (1, 2, 1, 2, 'stuff');
2410 These are the two builtin "special operators"; but the
2411 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2413 =head2 Unary operators: bool
2415 If you wish to test against boolean columns or functions within your
2416 database you can use the C<-bool> and C<-not_bool> operators. For
2417 example to test the column C<is_user> being true and the column
2418 C<is_enabled> being false you would use:-
2422 -not_bool => 'is_enabled',
2427 WHERE is_user AND NOT is_enabled
2429 If a more complex combination is required, testing more conditions,
2430 then you should use the and/or operators:-
2435 -not_bool => { two=> { -rlike => 'bar' } },
2436 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2447 (NOT ( three = ? OR three > ? ))
2450 =head2 Nested conditions, -and/-or prefixes
2452 So far, we've seen how multiple conditions are joined with a top-level
2453 C<AND>. We can change this by putting the different conditions we want in
2454 hashes and then putting those hashes in an array. For example:
2459 status => { -like => ['pending%', 'dispatched'] },
2463 status => 'unassigned',
2467 This data structure would create the following:
2469 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2470 OR ( user = ? AND status = ? ) )";
2471 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2474 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2475 to change the logic inside:
2481 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2482 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2489 $stmt = "WHERE ( user = ?
2490 AND ( ( workhrs > ? AND geo = ? )
2491 OR ( workhrs < ? OR geo = ? ) ) )";
2492 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2494 =head3 Algebraic inconsistency, for historical reasons
2496 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2497 operator goes C<outside> of the nested structure; whereas when connecting
2498 several constraints on one column, the C<-and> operator goes
2499 C<inside> the arrayref. Here is an example combining both features:
2502 -and => [a => 1, b => 2],
2503 -or => [c => 3, d => 4],
2504 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2509 WHERE ( ( ( a = ? AND b = ? )
2510 OR ( c = ? OR d = ? )
2511 OR ( e LIKE ? AND e LIKE ? ) ) )
2513 This difference in syntax is unfortunate but must be preserved for
2514 historical reasons. So be careful: the two examples below would
2515 seem algebraically equivalent, but they are not
2518 { -like => 'foo%' },
2519 { -like => '%bar' },
2521 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2524 { col => { -like => 'foo%' } },
2525 { col => { -like => '%bar' } },
2527 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2530 =head2 Literal SQL and value type operators
2532 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2533 side" is a column name and the "right side" is a value (normally rendered as
2534 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2535 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2536 alter this behavior. There are several ways of doing so.
2540 This is a virtual operator that signals the string to its right side is an
2541 identifier (a column name) and not a value. For example to compare two
2542 columns you would write:
2545 priority => { '<', 2 },
2546 requestor => { -ident => 'submitter' },
2551 $stmt = "WHERE priority < ? AND requestor = submitter";
2554 If you are maintaining legacy code you may see a different construct as
2555 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2560 This is a virtual operator that signals that the construct to its right side
2561 is a value to be passed to DBI. This is for example necessary when you want
2562 to write a where clause against an array (for RDBMS that support such
2563 datatypes). For example:
2566 array => { -value => [1, 2, 3] }
2571 $stmt = 'WHERE array = ?';
2572 @bind = ([1, 2, 3]);
2574 Note that if you were to simply say:
2580 the result would probably not be what you wanted:
2582 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2587 Finally, sometimes only literal SQL will do. To include a random snippet
2588 of SQL verbatim, you specify it as a scalar reference. Consider this only
2589 as a last resort. Usually there is a better way. For example:
2592 priority => { '<', 2 },
2593 requestor => { -in => \'(SELECT name FROM hitmen)' },
2598 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2601 Note that in this example, you only get one bind parameter back, since
2602 the verbatim SQL is passed as part of the statement.
2606 Never use untrusted input as a literal SQL argument - this is a massive
2607 security risk (there is no way to check literal snippets for SQL
2608 injections and other nastyness). If you need to deal with untrusted input
2609 use literal SQL with placeholders as described next.
2611 =head3 Literal SQL with placeholders and bind values (subqueries)
2613 If the literal SQL to be inserted has placeholders and bind values,
2614 use a reference to an arrayref (yes this is a double reference --
2615 not so common, but perfectly legal Perl). For example, to find a date
2616 in Postgres you can use something like this:
2619 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2624 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2627 Note that you must pass the bind values in the same format as they are returned
2628 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2629 to C<columns>, you must provide the bind values in the
2630 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2631 scalar value; most commonly the column name, but you can use any scalar value
2632 (including references and blessed references), L<SQL::Abstract> will simply
2633 pass it through intact. So if C<bindtype> is set to C<columns> the above
2634 example will look like:
2637 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2640 Literal SQL is especially useful for nesting parenthesized clauses in the
2641 main SQL query. Here is a first example:
2643 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2647 bar => \["IN ($sub_stmt)" => @sub_bind],
2652 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2653 WHERE c2 < ? AND c3 LIKE ?))";
2654 @bind = (1234, 100, "foo%");
2656 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2657 are expressed in the same way. Of course the C<$sub_stmt> and
2658 its associated bind values can be generated through a former call
2661 my ($sub_stmt, @sub_bind)
2662 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2663 c3 => {-like => "foo%"}});
2666 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2669 In the examples above, the subquery was used as an operator on a column;
2670 but the same principle also applies for a clause within the main C<%where>
2671 hash, like an EXISTS subquery:
2673 my ($sub_stmt, @sub_bind)
2674 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2675 my %where = ( -and => [
2677 \["EXISTS ($sub_stmt)" => @sub_bind],
2682 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2683 WHERE c1 = ? AND c2 > t0.c0))";
2687 Observe that the condition on C<c2> in the subquery refers to
2688 column C<t0.c0> of the main query: this is I<not> a bind
2689 value, so we have to express it through a scalar ref.
2690 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2691 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2692 what we wanted here.
2694 Finally, here is an example where a subquery is used
2695 for expressing unary negation:
2697 my ($sub_stmt, @sub_bind)
2698 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2699 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2701 lname => {like => '%son%'},
2702 \["NOT ($sub_stmt)" => @sub_bind],
2707 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2708 @bind = ('%son%', 10, 20)
2710 =head3 Deprecated usage of Literal SQL
2712 Below are some examples of archaic use of literal SQL. It is shown only as
2713 reference for those who deal with legacy code. Each example has a much
2714 better, cleaner and safer alternative that users should opt for in new code.
2720 my %where = ( requestor => \'IS NOT NULL' )
2722 $stmt = "WHERE requestor IS NOT NULL"
2724 This used to be the way of generating NULL comparisons, before the handling
2725 of C<undef> got formalized. For new code please use the superior syntax as
2726 described in L</Tests for NULL values>.
2730 my %where = ( requestor => \'= submitter' )
2732 $stmt = "WHERE requestor = submitter"
2734 This used to be the only way to compare columns. Use the superior L</-ident>
2735 method for all new code. For example an identifier declared in such a way
2736 will be properly quoted if L</quote_char> is properly set, while the legacy
2737 form will remain as supplied.
2741 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2743 $stmt = "WHERE completed > ? AND is_ready"
2744 @bind = ('2012-12-21')
2746 Using an empty string literal used to be the only way to express a boolean.
2747 For all new code please use the much more readable
2748 L<-bool|/Unary operators: bool> operator.
2754 These pages could go on for a while, since the nesting of the data
2755 structures this module can handle are pretty much unlimited (the
2756 module implements the C<WHERE> expansion as a recursive function
2757 internally). Your best bet is to "play around" with the module a
2758 little to see how the data structures behave, and choose the best
2759 format for your data based on that.
2761 And of course, all the values above will probably be replaced with
2762 variables gotten from forms or the command line. After all, if you
2763 knew everything ahead of time, you wouldn't have to worry about
2764 dynamically-generating SQL and could just hardwire it into your
2767 =head1 ORDER BY CLAUSES
2769 Some functions take an order by clause. This can either be a scalar (just a
2770 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2771 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2774 Given | Will Generate
2775 ---------------------------------------------------------------
2777 'colA' | ORDER BY colA
2779 [qw/colA colB/] | ORDER BY colA, colB
2781 {-asc => 'colA'} | ORDER BY colA ASC
2783 {-desc => 'colB'} | ORDER BY colB DESC
2785 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2787 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2789 \'colA DESC' | ORDER BY colA DESC
2791 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2792 | /* ...with $x bound to ? */
2795 { -asc => 'colA' }, | colA ASC,
2796 { -desc => [qw/colB/] }, | colB DESC,
2797 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2798 \'colE DESC', | colE DESC,
2799 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2800 ] | /* ...with $x bound to ? */
2801 ===============================================================
2805 =head1 SPECIAL OPERATORS
2807 my $sqlmaker = SQL::Abstract->new(special_ops => [
2811 my ($self, $field, $op, $arg) = @_;
2817 handler => 'method_name',
2821 A "special operator" is a SQL syntactic clause that can be
2822 applied to a field, instead of a usual binary operator.
2825 WHERE field IN (?, ?, ?)
2826 WHERE field BETWEEN ? AND ?
2827 WHERE MATCH(field) AGAINST (?, ?)
2829 Special operators IN and BETWEEN are fairly standard and therefore
2830 are builtin within C<SQL::Abstract> (as the overridable methods
2831 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2832 like the MATCH .. AGAINST example above which is specific to MySQL,
2833 you can write your own operator handlers - supply a C<special_ops>
2834 argument to the C<new> method. That argument takes an arrayref of
2835 operator definitions; each operator definition is a hashref with two
2842 the regular expression to match the operator
2846 Either a coderef or a plain scalar method name. In both cases
2847 the expected return is C<< ($sql, @bind) >>.
2849 When supplied with a method name, it is simply called on the
2850 L<SQL::Abstract> object as:
2852 $self->$method_name($field, $op, $arg)
2856 $field is the LHS of the operator
2857 $op is the part that matched the handler regex
2860 When supplied with a coderef, it is called as:
2862 $coderef->($self, $field, $op, $arg)
2867 For example, here is an implementation
2868 of the MATCH .. AGAINST syntax for MySQL
2870 my $sqlmaker = SQL::Abstract->new(special_ops => [
2872 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2873 {regex => qr/^match$/i,
2875 my ($self, $field, $op, $arg) = @_;
2876 $arg = [$arg] if not ref $arg;
2877 my $label = $self->_quote($field);
2878 my ($placeholder) = $self->_convert('?');
2879 my $placeholders = join ", ", (($placeholder) x @$arg);
2880 my $sql = $self->_sqlcase('match') . " ($label) "
2881 . $self->_sqlcase('against') . " ($placeholders) ";
2882 my @bind = $self->_bindtype($field, @$arg);
2883 return ($sql, @bind);
2890 =head1 UNARY OPERATORS
2892 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2896 my ($self, $op, $arg) = @_;
2902 handler => 'method_name',
2906 A "unary operator" is a SQL syntactic clause that can be
2907 applied to a field - the operator goes before the field
2909 You can write your own operator handlers - supply a C<unary_ops>
2910 argument to the C<new> method. That argument takes an arrayref of
2911 operator definitions; each operator definition is a hashref with two
2918 the regular expression to match the operator
2922 Either a coderef or a plain scalar method name. In both cases
2923 the expected return is C<< $sql >>.
2925 When supplied with a method name, it is simply called on the
2926 L<SQL::Abstract> object as:
2928 $self->$method_name($op, $arg)
2932 $op is the part that matched the handler regex
2933 $arg is the RHS or argument of the operator
2935 When supplied with a coderef, it is called as:
2937 $coderef->($self, $op, $arg)
2945 Thanks to some benchmarking by Mark Stosberg, it turns out that
2946 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2947 I must admit this wasn't an intentional design issue, but it's a
2948 byproduct of the fact that you get to control your C<DBI> handles
2951 To maximize performance, use a code snippet like the following:
2953 # prepare a statement handle using the first row
2954 # and then reuse it for the rest of the rows
2956 for my $href (@array_of_hashrefs) {
2957 $stmt ||= $sql->insert('table', $href);
2958 $sth ||= $dbh->prepare($stmt);
2959 $sth->execute($sql->values($href));
2962 The reason this works is because the keys in your C<$href> are sorted
2963 internally by B<SQL::Abstract>. Thus, as long as your data retains
2964 the same structure, you only have to generate the SQL the first time
2965 around. On subsequent queries, simply use the C<values> function provided
2966 by this module to return your values in the correct order.
2968 However this depends on the values having the same type - if, for
2969 example, the values of a where clause may either have values
2970 (resulting in sql of the form C<column = ?> with a single bind
2971 value), or alternatively the values might be C<undef> (resulting in
2972 sql of the form C<column IS NULL> with no bind value) then the
2973 caching technique suggested will not work.
2977 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2978 really like this part (I do, at least). Building up a complex query
2979 can be as simple as the following:
2986 use CGI::FormBuilder;
2989 my $form = CGI::FormBuilder->new(...);
2990 my $sql = SQL::Abstract->new;
2992 if ($form->submitted) {
2993 my $field = $form->field;
2994 my $id = delete $field->{id};
2995 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2998 Of course, you would still have to connect using C<DBI> to run the
2999 query, but the point is that if you make your form look like your
3000 table, the actual query script can be extremely simplistic.
3002 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3003 a fast interface to returning and formatting data. I frequently
3004 use these three modules together to write complex database query
3005 apps in under 50 lines.
3007 =head1 HOW TO CONTRIBUTE
3009 Contributions are always welcome, in all usable forms (we especially
3010 welcome documentation improvements). The delivery methods include git-
3011 or unified-diff formatted patches, GitHub pull requests, or plain bug
3012 reports either via RT or the Mailing list. Contributors are generally
3013 granted full access to the official repository after their first several
3014 patches pass successful review.
3016 This project is maintained in a git repository. The code and related tools are
3017 accessible at the following locations:
3021 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3023 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3025 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3027 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3033 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3034 Great care has been taken to preserve the I<published> behavior
3035 documented in previous versions in the 1.* family; however,
3036 some features that were previously undocumented, or behaved
3037 differently from the documentation, had to be changed in order
3038 to clarify the semantics. Hence, client code that was relying
3039 on some dark areas of C<SQL::Abstract> v1.*
3040 B<might behave differently> in v1.50.
3042 The main changes are:
3048 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3052 support for the { operator => \"..." } construct (to embed literal SQL)
3056 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3060 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3064 defensive programming: check arguments
3068 fixed bug with global logic, which was previously implemented
3069 through global variables yielding side-effects. Prior versions would
3070 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3071 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3072 Now this is interpreted
3073 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3078 fixed semantics of _bindtype on array args
3082 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3083 we just avoid shifting arrays within that tree.
3087 dropped the C<_modlogic> function
3091 =head1 ACKNOWLEDGEMENTS
3093 There are a number of individuals that have really helped out with
3094 this module. Unfortunately, most of them submitted bugs via CPAN
3095 so I have no idea who they are! But the people I do know are:
3097 Ash Berlin (order_by hash term support)
3098 Matt Trout (DBIx::Class support)
3099 Mark Stosberg (benchmarking)
3100 Chas Owens (initial "IN" operator support)
3101 Philip Collins (per-field SQL functions)
3102 Eric Kolve (hashref "AND" support)
3103 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3104 Dan Kubb (support for "quote_char" and "name_sep")
3105 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3106 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3107 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3108 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3109 Oliver Charles (support for "RETURNING" after "INSERT")
3115 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3119 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3121 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3123 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3124 While not an official support venue, C<DBIx::Class> makes heavy use of
3125 C<SQL::Abstract>, and as such list members there are very familiar with
3126 how to create queries.
3130 This module is free software; you may copy this under the same
3131 terms as perl itself (either the GNU General Public License or
3132 the Artistic License)