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]);
992 my ($self, $op, $args) = @_;
993 my ($left, $low, $high) = @$args;
994 my ($rhsql, @rhbind) = do {
996 puke "Single arg to between must be a literal"
997 unless $low->{-literal};
1000 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
1001 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
1002 @{$l}[1..$#$l], @{$h}[1..$#$h])
1005 my ($lhsql, @lhbind) = $self->render_aqt($left);
1007 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
1011 }), 'between', 'not between'),
1014 my ($self, $op, $args) = @_;
1015 my ($lhs, $rhs) = @$args;
1018 my ($sql, @bind) = $self->render_aqt($_);
1019 push @in_bind, @bind;
1022 my ($lhsql, @lbind) = $self->render_aqt($lhs);
1024 $lhsql.' '.$self->_sqlcase($op).' ( '
1025 .join(', ', @in_sql)
1030 }), 'in', 'not in'),
1031 (map +($_ => '_render_unop_postfix'),
1032 'is null', 'is not null', 'asc', 'desc',
1036 my %unop_postfix = map +($_ => 1),
1037 'is null', 'is not null',
1042 my ($self, $v) = @_;
1043 my ($op, @args) = @$v;
1044 if (my $r = $self->{render_op}{$op}) {
1045 return $self->$r($op, \@args);
1047 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1048 if ($us and @args > 1) {
1049 puke "Special op '${op}' requires first value to be identifier"
1050 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1051 my $k = join(($self->{name_sep}||'.'), @$ident);
1052 local our $Expand_Depth = 1;
1053 return $self->${\($us->{handler})}($k, $op, $args[1]);
1055 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1056 return $self->${\($us->{handler})}($op, $args[0]);
1058 if (@args == 1 and $op !~ /^(and|or)$/) {
1059 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1060 my $op_sql = $self->_sqlcase($op);
1062 $unop_postfix{lc($op)}
1063 ? "${expr_sql} ${op_sql}"
1064 : "${op_sql} ${expr_sql}"
1066 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1068 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1069 return '' unless @parts;
1070 my $is_andor = !!($op =~ /^(and|or)$/);
1071 return @{$parts[0]} if $is_andor and @parts == 1;
1072 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1073 ' '.$self->_sqlcase($op).' ',
1078 map @{$_}[1..$#$_], @parts
1084 sub _render_unop_postfix {
1085 my ($self, $op, $v) = @_;
1086 my ($arg, @argh) = @$v;
1087 puke "Argh" if @argh;
1088 my ($expr_sql, @bind) = $self->render_aqt($arg);
1089 my $op_sql = $self->_sqlcase($op);
1090 return ($expr_sql.' '.$op_sql, @bind);
1093 # Some databases (SQLite) treat col IN (1, 2) different from
1094 # col IN ( (1, 2) ). Use this to strip all outer parens while
1095 # adding them back in the corresponding method
1096 sub _open_outer_paren {
1097 my ($self, $sql) = @_;
1099 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1101 # there are closing parens inside, need the heavy duty machinery
1102 # to reevaluate the extraction starting from $sql (full reevaluation)
1103 if ($inner =~ /\)/) {
1104 require Text::Balanced;
1106 my (undef, $remainder) = do {
1107 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1109 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1112 # the entire expression needs to be a balanced bracketed thing
1113 # (after an extract no remainder sans trailing space)
1114 last if defined $remainder and $remainder =~ /\S/;
1124 #======================================================================
1126 #======================================================================
1128 sub _expand_order_by {
1129 my ($self, $arg) = @_;
1131 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1133 my $expander = sub {
1134 my ($self, $dir, $expr) = @_;
1135 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1136 foreach my $arg (@to_expand) {
1140 and grep /^-(asc|desc)$/, keys %$arg
1142 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1146 defined($dir) ? { -op => [ $dir =~ /^-?(.*)$/ ,=> $_ ] } : $_
1148 map $self->expand_expr($_, -ident),
1149 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1150 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1153 local @{$self->{expand}}{qw(-asc -desc)} = (($expander) x 2);
1155 return $self->$expander(undef, $arg);
1159 my ($self, $arg) = @_;
1161 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1163 my ($sql, @bind) = $self->render_aqt($expanded);
1165 return '' unless length($sql);
1167 my $final_sql = $self->_sqlcase(' order by ').$sql;
1169 return wantarray ? ($final_sql, @bind) : $final_sql;
1172 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1174 sub _order_by_chunks {
1175 my ($self, $arg) = @_;
1177 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1179 return $self->_chunkify_order_by($expanded);
1182 sub _chunkify_order_by {
1183 my ($self, $expanded) = @_;
1185 return grep length, $self->render_aqt($expanded)
1186 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1189 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1190 return map $self->_chunkify_order_by($_), @$l;
1192 return [ $self->render_aqt($_) ];
1196 #======================================================================
1197 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1198 #======================================================================
1204 $self->_expand_maybe_list_expr($from, undef, -ident)
1209 #======================================================================
1211 #======================================================================
1213 sub _expand_maybe_list_expr {
1214 my ($self, $expr, $logic, $default) = @_;
1216 if (ref($expr) eq 'ARRAY') {
1218 map $self->expand_expr($_, $default), @$expr
1225 return $self->expand_expr($e, $default);
1228 # highly optimized, as it's called way too often
1230 # my ($self, $label) = @_;
1232 return '' unless defined $_[1];
1233 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1234 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1236 unless ($_[0]->{quote_char}) {
1237 if (ref($_[1]) eq 'ARRAY') {
1238 return join($_[0]->{name_sep}||'.', @{$_[1]});
1240 $_[0]->_assert_pass_injection_guard($_[1]);
1245 my $qref = ref $_[0]->{quote_char};
1247 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1248 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1249 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1251 my $esc = $_[0]->{escape_char} || $r;
1253 # parts containing * are naturally unquoted
1255 $_[0]->{name_sep}||'',
1259 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1261 (ref($_[1]) eq 'ARRAY'
1265 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1273 # Conversion, if applicable
1275 #my ($self, $arg) = @_;
1276 if ($_[0]->{convert_where}) {
1277 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1284 #my ($self, $col, @vals) = @_;
1285 # called often - tighten code
1286 return $_[0]->{bindtype} eq 'columns'
1287 ? map {[$_[1], $_]} @_[2 .. $#_]
1292 # Dies if any element of @bind is not in [colname => value] format
1293 # if bindtype is 'columns'.
1294 sub _assert_bindval_matches_bindtype {
1295 # my ($self, @bind) = @_;
1297 if ($self->{bindtype} eq 'columns') {
1299 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1300 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1306 sub _join_sql_clauses {
1307 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1309 if (@$clauses_aref > 1) {
1310 my $join = " " . $self->_sqlcase($logic) . " ";
1311 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1312 return ($sql, @$bind_aref);
1314 elsif (@$clauses_aref) {
1315 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1318 return (); # if no SQL, ignore @$bind_aref
1323 # Fix SQL case, if so requested
1325 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1326 # don't touch the argument ... crooked logic, but let's not change it!
1327 return $_[0]->{case} ? $_[1] : uc($_[1]);
1331 #======================================================================
1332 # DISPATCHING FROM REFKIND
1333 #======================================================================
1336 my ($self, $data) = @_;
1338 return 'UNDEF' unless defined $data;
1340 # blessed objects are treated like scalars
1341 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1343 return 'SCALAR' unless $ref;
1346 while ($ref eq 'REF') {
1348 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1352 return ($ref||'SCALAR') . ('REF' x $n_steps);
1356 my ($self, $data) = @_;
1357 my @try = ($self->_refkind($data));
1358 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1359 push @try, 'FALLBACK';
1363 sub _METHOD_FOR_refkind {
1364 my ($self, $meth_prefix, $data) = @_;
1367 for (@{$self->_try_refkind($data)}) {
1368 $method = $self->can($meth_prefix."_".$_)
1372 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1376 sub _SWITCH_refkind {
1377 my ($self, $data, $dispatch_table) = @_;
1380 for (@{$self->_try_refkind($data)}) {
1381 $coderef = $dispatch_table->{$_}
1385 puke "no dispatch entry for ".$self->_refkind($data)
1394 #======================================================================
1395 # VALUES, GENERATE, AUTOLOAD
1396 #======================================================================
1398 # LDNOTE: original code from nwiger, didn't touch code in that section
1399 # I feel the AUTOLOAD stuff should not be the default, it should
1400 # only be activated on explicit demand by user.
1404 my $data = shift || return;
1405 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1406 unless ref $data eq 'HASH';
1409 foreach my $k (sort keys %$data) {
1410 my $v = $data->{$k};
1411 $self->_SWITCH_refkind($v, {
1413 if ($self->{array_datatypes}) { # array datatype
1414 push @all_bind, $self->_bindtype($k, $v);
1416 else { # literal SQL with bind
1417 my ($sql, @bind) = @$v;
1418 $self->_assert_bindval_matches_bindtype(@bind);
1419 push @all_bind, @bind;
1422 ARRAYREFREF => sub { # literal SQL with bind
1423 my ($sql, @bind) = @${$v};
1424 $self->_assert_bindval_matches_bindtype(@bind);
1425 push @all_bind, @bind;
1427 SCALARREF => sub { # literal SQL without bind
1429 SCALAR_or_UNDEF => sub {
1430 push @all_bind, $self->_bindtype($k, $v);
1441 my(@sql, @sqlq, @sqlv);
1445 if ($ref eq 'HASH') {
1446 for my $k (sort keys %$_) {
1449 my $label = $self->_quote($k);
1450 if ($r eq 'ARRAY') {
1451 # literal SQL with bind
1452 my ($sql, @bind) = @$v;
1453 $self->_assert_bindval_matches_bindtype(@bind);
1454 push @sqlq, "$label = $sql";
1456 } elsif ($r eq 'SCALAR') {
1457 # literal SQL without bind
1458 push @sqlq, "$label = $$v";
1460 push @sqlq, "$label = ?";
1461 push @sqlv, $self->_bindtype($k, $v);
1464 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1465 } elsif ($ref eq 'ARRAY') {
1466 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1469 if ($r eq 'ARRAY') { # literal SQL with bind
1470 my ($sql, @bind) = @$v;
1471 $self->_assert_bindval_matches_bindtype(@bind);
1474 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1475 # embedded literal SQL
1482 push @sql, '(' . join(', ', @sqlq) . ')';
1483 } elsif ($ref eq 'SCALAR') {
1487 # strings get case twiddled
1488 push @sql, $self->_sqlcase($_);
1492 my $sql = join ' ', @sql;
1494 # this is pretty tricky
1495 # if ask for an array, return ($stmt, @bind)
1496 # otherwise, s/?/shift @sqlv/ to put it inline
1498 return ($sql, @sqlv);
1500 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1501 ref $d ? $d->[1] : $d/e;
1510 # This allows us to check for a local, then _form, attr
1512 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1513 return $self->generate($name, @_);
1524 SQL::Abstract - Generate SQL from Perl data structures
1530 my $sql = SQL::Abstract->new;
1532 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1534 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1536 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1538 my($stmt, @bind) = $sql->delete($table, \%where);
1540 # Then, use these in your DBI statements
1541 my $sth = $dbh->prepare($stmt);
1542 $sth->execute(@bind);
1544 # Just generate the WHERE clause
1545 my($stmt, @bind) = $sql->where(\%where, $order);
1547 # Return values in the same order, for hashed queries
1548 # See PERFORMANCE section for more details
1549 my @bind = $sql->values(\%fieldvals);
1553 This module was inspired by the excellent L<DBIx::Abstract>.
1554 However, in using that module I found that what I really wanted
1555 to do was generate SQL, but still retain complete control over my
1556 statement handles and use the DBI interface. So, I set out to
1557 create an abstract SQL generation module.
1559 While based on the concepts used by L<DBIx::Abstract>, there are
1560 several important differences, especially when it comes to WHERE
1561 clauses. I have modified the concepts used to make the SQL easier
1562 to generate from Perl data structures and, IMO, more intuitive.
1563 The underlying idea is for this module to do what you mean, based
1564 on the data structures you provide it. The big advantage is that
1565 you don't have to modify your code every time your data changes,
1566 as this module figures it out.
1568 To begin with, an SQL INSERT is as easy as just specifying a hash
1569 of C<key=value> pairs:
1572 name => 'Jimbo Bobson',
1573 phone => '123-456-7890',
1574 address => '42 Sister Lane',
1575 city => 'St. Louis',
1576 state => 'Louisiana',
1579 The SQL can then be generated with this:
1581 my($stmt, @bind) = $sql->insert('people', \%data);
1583 Which would give you something like this:
1585 $stmt = "INSERT INTO people
1586 (address, city, name, phone, state)
1587 VALUES (?, ?, ?, ?, ?)";
1588 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1589 '123-456-7890', 'Louisiana');
1591 These are then used directly in your DBI code:
1593 my $sth = $dbh->prepare($stmt);
1594 $sth->execute(@bind);
1596 =head2 Inserting and Updating Arrays
1598 If your database has array types (like for example Postgres),
1599 activate the special option C<< array_datatypes => 1 >>
1600 when creating the C<SQL::Abstract> object.
1601 Then you may use an arrayref to insert and update database array types:
1603 my $sql = SQL::Abstract->new(array_datatypes => 1);
1605 planets => [qw/Mercury Venus Earth Mars/]
1608 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1612 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1614 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1617 =head2 Inserting and Updating SQL
1619 In order to apply SQL functions to elements of your C<%data> you may
1620 specify a reference to an arrayref for the given hash value. For example,
1621 if you need to execute the Oracle C<to_date> function on a value, you can
1622 say something like this:
1626 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1629 The first value in the array is the actual SQL. Any other values are
1630 optional and would be included in the bind values array. This gives
1633 my($stmt, @bind) = $sql->insert('people', \%data);
1635 $stmt = "INSERT INTO people (name, date_entered)
1636 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1637 @bind = ('Bill', '03/02/2003');
1639 An UPDATE is just as easy, all you change is the name of the function:
1641 my($stmt, @bind) = $sql->update('people', \%data);
1643 Notice that your C<%data> isn't touched; the module will generate
1644 the appropriately quirky SQL for you automatically. Usually you'll
1645 want to specify a WHERE clause for your UPDATE, though, which is
1646 where handling C<%where> hashes comes in handy...
1648 =head2 Complex where statements
1650 This module can generate pretty complicated WHERE statements
1651 easily. For example, simple C<key=value> pairs are taken to mean
1652 equality, and if you want to see if a field is within a set
1653 of values, you can use an arrayref. Let's say we wanted to
1654 SELECT some data based on this criteria:
1657 requestor => 'inna',
1658 worker => ['nwiger', 'rcwe', 'sfz'],
1659 status => { '!=', 'completed' }
1662 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1664 The above would give you something like this:
1666 $stmt = "SELECT * FROM tickets WHERE
1667 ( requestor = ? ) AND ( status != ? )
1668 AND ( worker = ? OR worker = ? OR worker = ? )";
1669 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1671 Which you could then use in DBI code like so:
1673 my $sth = $dbh->prepare($stmt);
1674 $sth->execute(@bind);
1680 The methods are simple. There's one for every major SQL operation,
1681 and a constructor you use first. The arguments are specified in a
1682 similar order for each method (table, then fields, then a where
1683 clause) to try and simplify things.
1685 =head2 new(option => 'value')
1687 The C<new()> function takes a list of options and values, and returns
1688 a new B<SQL::Abstract> object which can then be used to generate SQL
1689 through the methods below. The options accepted are:
1695 If set to 'lower', then SQL will be generated in all lowercase. By
1696 default SQL is generated in "textbook" case meaning something like:
1698 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1700 Any setting other than 'lower' is ignored.
1704 This determines what the default comparison operator is. By default
1705 it is C<=>, meaning that a hash like this:
1707 %where = (name => 'nwiger', email => 'nate@wiger.org');
1709 Will generate SQL like this:
1711 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1713 However, you may want loose comparisons by default, so if you set
1714 C<cmp> to C<like> you would get SQL such as:
1716 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1718 You can also override the comparison on an individual basis - see
1719 the huge section on L</"WHERE CLAUSES"> at the bottom.
1721 =item sqltrue, sqlfalse
1723 Expressions for inserting boolean values within SQL statements.
1724 By default these are C<1=1> and C<1=0>. They are used
1725 by the special operators C<-in> and C<-not_in> for generating
1726 correct SQL even when the argument is an empty array (see below).
1730 This determines the default logical operator for multiple WHERE
1731 statements in arrays or hashes. If absent, the default logic is "or"
1732 for arrays, and "and" for hashes. This means that a WHERE
1736 event_date => {'>=', '2/13/99'},
1737 event_date => {'<=', '4/24/03'},
1740 will generate SQL like this:
1742 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1744 This is probably not what you want given this query, though (look
1745 at the dates). To change the "OR" to an "AND", simply specify:
1747 my $sql = SQL::Abstract->new(logic => 'and');
1749 Which will change the above C<WHERE> to:
1751 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1753 The logic can also be changed locally by inserting
1754 a modifier in front of an arrayref:
1756 @where = (-and => [event_date => {'>=', '2/13/99'},
1757 event_date => {'<=', '4/24/03'} ]);
1759 See the L</"WHERE CLAUSES"> section for explanations.
1763 This will automatically convert comparisons using the specified SQL
1764 function for both column and value. This is mostly used with an argument
1765 of C<upper> or C<lower>, so that the SQL will have the effect of
1766 case-insensitive "searches". For example, this:
1768 $sql = SQL::Abstract->new(convert => 'upper');
1769 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1771 Will turn out the following SQL:
1773 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1775 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1776 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1777 not validate this option; it will just pass through what you specify verbatim).
1781 This is a kludge because many databases suck. For example, you can't
1782 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1783 Instead, you have to use C<bind_param()>:
1785 $sth->bind_param(1, 'reg data');
1786 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1788 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1789 which loses track of which field each slot refers to. Fear not.
1791 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1792 Currently, you can specify either C<normal> (default) or C<columns>. If you
1793 specify C<columns>, you will get an array that looks like this:
1795 my $sql = SQL::Abstract->new(bindtype => 'columns');
1796 my($stmt, @bind) = $sql->insert(...);
1799 [ 'column1', 'value1' ],
1800 [ 'column2', 'value2' ],
1801 [ 'column3', 'value3' ],
1804 You can then iterate through this manually, using DBI's C<bind_param()>.
1806 $sth->prepare($stmt);
1809 my($col, $data) = @$_;
1810 if ($col eq 'details' || $col eq 'comments') {
1811 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1812 } elsif ($col eq 'image') {
1813 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1815 $sth->bind_param($i, $data);
1819 $sth->execute; # execute without @bind now
1821 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1822 Basically, the advantage is still that you don't have to care which fields
1823 are or are not included. You could wrap that above C<for> loop in a simple
1824 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1825 get a layer of abstraction over manual SQL specification.
1827 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1828 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1829 will expect the bind values in this format.
1833 This is the character that a table or column name will be quoted
1834 with. By default this is an empty string, but you could set it to
1835 the character C<`>, to generate SQL like this:
1837 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1839 Alternatively, you can supply an array ref of two items, the first being the left
1840 hand quote character, and the second the right hand quote character. For
1841 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1842 that generates SQL like this:
1844 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1846 Quoting is useful if you have tables or columns names that are reserved
1847 words in your database's SQL dialect.
1851 This is the character that will be used to escape L</quote_char>s appearing
1852 in an identifier before it has been quoted.
1854 The parameter default in case of a single L</quote_char> character is the quote
1857 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1858 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1859 of the B<opening (left)> L</quote_char> within the identifier are currently left
1860 untouched. The default for opening-closing-style quotes may change in future
1861 versions, thus you are B<strongly encouraged> to specify the escape character
1866 This is the character that separates a table and column name. It is
1867 necessary to specify this when the C<quote_char> option is selected,
1868 so that tables and column names can be individually quoted like this:
1870 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1872 =item injection_guard
1874 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1875 column name specified in a query structure. This is a safety mechanism to avoid
1876 injection attacks when mishandling user input e.g.:
1878 my %condition_as_column_value_pairs = get_values_from_user();
1879 $sqla->select( ... , \%condition_as_column_value_pairs );
1881 If the expression matches an exception is thrown. Note that literal SQL
1882 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1884 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1886 =item array_datatypes
1888 When this option is true, arrayrefs in INSERT or UPDATE are
1889 interpreted as array datatypes and are passed directly
1891 When this option is false, arrayrefs are interpreted
1892 as literal SQL, just like refs to arrayrefs
1893 (but this behavior is for backwards compatibility; when writing
1894 new queries, use the "reference to arrayref" syntax
1900 Takes a reference to a list of "special operators"
1901 to extend the syntax understood by L<SQL::Abstract>.
1902 See section L</"SPECIAL OPERATORS"> for details.
1906 Takes a reference to a list of "unary operators"
1907 to extend the syntax understood by L<SQL::Abstract>.
1908 See section L</"UNARY OPERATORS"> for details.
1914 =head2 insert($table, \@values || \%fieldvals, \%options)
1916 This is the simplest function. You simply give it a table name
1917 and either an arrayref of values or hashref of field/value pairs.
1918 It returns an SQL INSERT statement and a list of bind values.
1919 See the sections on L</"Inserting and Updating Arrays"> and
1920 L</"Inserting and Updating SQL"> for information on how to insert
1921 with those data types.
1923 The optional C<\%options> hash reference may contain additional
1924 options to generate the insert SQL. Currently supported options
1931 Takes either a scalar of raw SQL fields, or an array reference of
1932 field names, and adds on an SQL C<RETURNING> statement at the end.
1933 This allows you to return data generated by the insert statement
1934 (such as row IDs) without performing another C<SELECT> statement.
1935 Note, however, this is not part of the SQL standard and may not
1936 be supported by all database engines.
1940 =head2 update($table, \%fieldvals, \%where, \%options)
1942 This takes a table, hashref of field/value pairs, and an optional
1943 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1945 See the sections on L</"Inserting and Updating Arrays"> and
1946 L</"Inserting and Updating SQL"> for information on how to insert
1947 with those data types.
1949 The optional C<\%options> hash reference may contain additional
1950 options to generate the update SQL. Currently supported options
1957 See the C<returning> option to
1958 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1962 =head2 select($source, $fields, $where, $order)
1964 This returns a SQL SELECT statement and associated list of bind values, as
1965 specified by the arguments:
1971 Specification of the 'FROM' part of the statement.
1972 The argument can be either a plain scalar (interpreted as a table
1973 name, will be quoted), or an arrayref (interpreted as a list
1974 of table names, joined by commas, quoted), or a scalarref
1975 (literal SQL, not quoted).
1979 Specification of the list of fields to retrieve from
1981 The argument can be either an arrayref (interpreted as a list
1982 of field names, will be joined by commas and quoted), or a
1983 plain scalar (literal SQL, not quoted).
1984 Please observe that this API is not as flexible as that of
1985 the first argument C<$source>, for backwards compatibility reasons.
1989 Optional argument to specify the WHERE part of the query.
1990 The argument is most often a hashref, but can also be
1991 an arrayref or plain scalar --
1992 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1996 Optional argument to specify the ORDER BY part of the query.
1997 The argument can be a scalar, a hashref or an arrayref
1998 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2004 =head2 delete($table, \%where, \%options)
2006 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2007 It returns an SQL DELETE statement and list of bind values.
2009 The optional C<\%options> hash reference may contain additional
2010 options to generate the delete SQL. Currently supported options
2017 See the C<returning> option to
2018 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2022 =head2 where(\%where, $order)
2024 This is used to generate just the WHERE clause. For example,
2025 if you have an arbitrary data structure and know what the
2026 rest of your SQL is going to look like, but want an easy way
2027 to produce a WHERE clause, use this. It returns an SQL WHERE
2028 clause and list of bind values.
2031 =head2 values(\%data)
2033 This just returns the values from the hash C<%data>, in the same
2034 order that would be returned from any of the other above queries.
2035 Using this allows you to markedly speed up your queries if you
2036 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2038 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2040 Warning: This is an experimental method and subject to change.
2042 This returns arbitrarily generated SQL. It's a really basic shortcut.
2043 It will return two different things, depending on return context:
2045 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2046 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2048 These would return the following:
2050 # First calling form
2051 $stmt = "CREATE TABLE test (?, ?)";
2052 @bind = (field1, field2);
2054 # Second calling form
2055 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2057 Depending on what you're trying to do, it's up to you to choose the correct
2058 format. In this example, the second form is what you would want.
2062 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2066 ALTER SESSION SET nls_date_format = 'MM/YY'
2068 You get the idea. Strings get their case twiddled, but everything
2069 else remains verbatim.
2071 =head1 EXPORTABLE FUNCTIONS
2073 =head2 is_plain_value
2075 Determines if the supplied argument is a plain value as understood by this
2080 =item * The value is C<undef>
2082 =item * The value is a non-reference
2084 =item * The value is an object with stringification overloading
2086 =item * The value is of the form C<< { -value => $anything } >>
2090 On failure returns C<undef>, on success returns a B<scalar> reference
2091 to the original supplied argument.
2097 The stringification overloading detection is rather advanced: it takes
2098 into consideration not only the presence of a C<""> overload, but if that
2099 fails also checks for enabled
2100 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2101 on either C<0+> or C<bool>.
2103 Unfortunately testing in the field indicates that this
2104 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2105 but only when very large numbers of stringifying objects are involved.
2106 At the time of writing ( Sep 2014 ) there is no clear explanation of
2107 the direct cause, nor is there a manageably small test case that reliably
2108 reproduces the problem.
2110 If you encounter any of the following exceptions in B<random places within
2111 your application stack> - this module may be to blame:
2113 Operation "ne": no method found,
2114 left argument in overloaded package <something>,
2115 right argument in overloaded package <something>
2119 Stub found while resolving method "???" overloading """" in package <something>
2121 If you fall victim to the above - please attempt to reduce the problem
2122 to something that could be sent to the L<SQL::Abstract developers
2123 |DBIx::Class/GETTING HELP/SUPPORT>
2124 (either publicly or privately). As a workaround in the meantime you can
2125 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2126 value, which will most likely eliminate your problem (at the expense of
2127 not being able to properly detect exotic forms of stringification).
2129 This notice and environment variable will be removed in a future version,
2130 as soon as the underlying problem is found and a reliable workaround is
2135 =head2 is_literal_value
2137 Determines if the supplied argument is a literal value as understood by this
2142 =item * C<\$sql_string>
2144 =item * C<\[ $sql_string, @bind_values ]>
2148 On failure returns C<undef>, on success returns an B<array> reference
2149 containing the unpacked version of the supplied literal SQL and bind values.
2151 =head1 WHERE CLAUSES
2155 This module uses a variation on the idea from L<DBIx::Abstract>. It
2156 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2157 module is that things in arrays are OR'ed, and things in hashes
2160 The easiest way to explain is to show lots of examples. After
2161 each C<%where> hash shown, it is assumed you used:
2163 my($stmt, @bind) = $sql->where(\%where);
2165 However, note that the C<%where> hash can be used directly in any
2166 of the other functions as well, as described above.
2168 =head2 Key-value pairs
2170 So, let's get started. To begin, a simple hash:
2174 status => 'completed'
2177 Is converted to SQL C<key = val> statements:
2179 $stmt = "WHERE user = ? AND status = ?";
2180 @bind = ('nwiger', 'completed');
2182 One common thing I end up doing is having a list of values that
2183 a field can be in. To do this, simply specify a list inside of
2188 status => ['assigned', 'in-progress', 'pending'];
2191 This simple code will create the following:
2193 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2194 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2196 A field associated to an empty arrayref will be considered a
2197 logical false and will generate 0=1.
2199 =head2 Tests for NULL values
2201 If the value part is C<undef> then this is converted to SQL <IS NULL>
2210 $stmt = "WHERE user = ? AND status IS NULL";
2213 To test if a column IS NOT NULL:
2217 status => { '!=', undef },
2220 =head2 Specific comparison operators
2222 If you want to specify a different type of operator for your comparison,
2223 you can use a hashref for a given column:
2227 status => { '!=', 'completed' }
2230 Which would generate:
2232 $stmt = "WHERE user = ? AND status != ?";
2233 @bind = ('nwiger', 'completed');
2235 To test against multiple values, just enclose the values in an arrayref:
2237 status => { '=', ['assigned', 'in-progress', 'pending'] };
2239 Which would give you:
2241 "WHERE status = ? OR status = ? OR status = ?"
2244 The hashref can also contain multiple pairs, in which case it is expanded
2245 into an C<AND> of its elements:
2249 status => { '!=', 'completed', -not_like => 'pending%' }
2252 # Or more dynamically, like from a form
2253 $where{user} = 'nwiger';
2254 $where{status}{'!='} = 'completed';
2255 $where{status}{'-not_like'} = 'pending%';
2257 # Both generate this
2258 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2259 @bind = ('nwiger', 'completed', 'pending%');
2262 To get an OR instead, you can combine it with the arrayref idea:
2266 priority => [ { '=', 2 }, { '>', 5 } ]
2269 Which would generate:
2271 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2272 @bind = ('2', '5', 'nwiger');
2274 If you want to include literal SQL (with or without bind values), just use a
2275 scalar reference or reference to an arrayref as the value:
2278 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2279 date_expires => { '<' => \"now()" }
2282 Which would generate:
2284 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2285 @bind = ('11/26/2008');
2288 =head2 Logic and nesting operators
2290 In the example above,
2291 there is a subtle trap if you want to say something like
2292 this (notice the C<AND>):
2294 WHERE priority != ? AND priority != ?
2296 Because, in Perl you I<can't> do this:
2298 priority => { '!=' => 2, '!=' => 1 }
2300 As the second C<!=> key will obliterate the first. The solution
2301 is to use the special C<-modifier> form inside an arrayref:
2303 priority => [ -and => {'!=', 2},
2307 Normally, these would be joined by C<OR>, but the modifier tells it
2308 to use C<AND> instead. (Hint: You can use this in conjunction with the
2309 C<logic> option to C<new()> in order to change the way your queries
2310 work by default.) B<Important:> Note that the C<-modifier> goes
2311 B<INSIDE> the arrayref, as an extra first element. This will
2312 B<NOT> do what you think it might:
2314 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2316 Here is a quick list of equivalencies, since there is some overlap:
2319 status => {'!=', 'completed', 'not like', 'pending%' }
2320 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2323 status => {'=', ['assigned', 'in-progress']}
2324 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2325 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2329 =head2 Special operators: IN, BETWEEN, etc.
2331 You can also use the hashref format to compare a list of fields using the
2332 C<IN> comparison operator, by specifying the list as an arrayref:
2335 status => 'completed',
2336 reportid => { -in => [567, 2335, 2] }
2339 Which would generate:
2341 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2342 @bind = ('completed', '567', '2335', '2');
2344 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2347 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2348 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2349 'sqltrue' (by default: C<1=1>).
2351 In addition to the array you can supply a chunk of literal sql or
2352 literal sql with bind:
2355 customer => { -in => \[
2356 'SELECT cust_id FROM cust WHERE balance > ?',
2359 status => { -in => \'SELECT status_codes FROM states' },
2365 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2366 AND status IN ( SELECT status_codes FROM states )
2370 Finally, if the argument to C<-in> is not a reference, it will be
2371 treated as a single-element array.
2373 Another pair of operators is C<-between> and C<-not_between>,
2374 used with an arrayref of two values:
2378 completion_date => {
2379 -not_between => ['2002-10-01', '2003-02-06']
2385 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2387 Just like with C<-in> all plausible combinations of literal SQL
2391 start0 => { -between => [ 1, 2 ] },
2392 start1 => { -between => \["? AND ?", 1, 2] },
2393 start2 => { -between => \"lower(x) AND upper(y)" },
2394 start3 => { -between => [
2396 \["upper(?)", 'stuff' ],
2403 ( start0 BETWEEN ? AND ? )
2404 AND ( start1 BETWEEN ? AND ? )
2405 AND ( start2 BETWEEN lower(x) AND upper(y) )
2406 AND ( start3 BETWEEN lower(x) AND upper(?) )
2408 @bind = (1, 2, 1, 2, 'stuff');
2411 These are the two builtin "special operators"; but the
2412 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2414 =head2 Unary operators: bool
2416 If you wish to test against boolean columns or functions within your
2417 database you can use the C<-bool> and C<-not_bool> operators. For
2418 example to test the column C<is_user> being true and the column
2419 C<is_enabled> being false you would use:-
2423 -not_bool => 'is_enabled',
2428 WHERE is_user AND NOT is_enabled
2430 If a more complex combination is required, testing more conditions,
2431 then you should use the and/or operators:-
2436 -not_bool => { two=> { -rlike => 'bar' } },
2437 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2448 (NOT ( three = ? OR three > ? ))
2451 =head2 Nested conditions, -and/-or prefixes
2453 So far, we've seen how multiple conditions are joined with a top-level
2454 C<AND>. We can change this by putting the different conditions we want in
2455 hashes and then putting those hashes in an array. For example:
2460 status => { -like => ['pending%', 'dispatched'] },
2464 status => 'unassigned',
2468 This data structure would create the following:
2470 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2471 OR ( user = ? AND status = ? ) )";
2472 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2475 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2476 to change the logic inside:
2482 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2483 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2490 $stmt = "WHERE ( user = ?
2491 AND ( ( workhrs > ? AND geo = ? )
2492 OR ( workhrs < ? OR geo = ? ) ) )";
2493 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2495 =head3 Algebraic inconsistency, for historical reasons
2497 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2498 operator goes C<outside> of the nested structure; whereas when connecting
2499 several constraints on one column, the C<-and> operator goes
2500 C<inside> the arrayref. Here is an example combining both features:
2503 -and => [a => 1, b => 2],
2504 -or => [c => 3, d => 4],
2505 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2510 WHERE ( ( ( a = ? AND b = ? )
2511 OR ( c = ? OR d = ? )
2512 OR ( e LIKE ? AND e LIKE ? ) ) )
2514 This difference in syntax is unfortunate but must be preserved for
2515 historical reasons. So be careful: the two examples below would
2516 seem algebraically equivalent, but they are not
2519 { -like => 'foo%' },
2520 { -like => '%bar' },
2522 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2525 { col => { -like => 'foo%' } },
2526 { col => { -like => '%bar' } },
2528 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2531 =head2 Literal SQL and value type operators
2533 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2534 side" is a column name and the "right side" is a value (normally rendered as
2535 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2536 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2537 alter this behavior. There are several ways of doing so.
2541 This is a virtual operator that signals the string to its right side is an
2542 identifier (a column name) and not a value. For example to compare two
2543 columns you would write:
2546 priority => { '<', 2 },
2547 requestor => { -ident => 'submitter' },
2552 $stmt = "WHERE priority < ? AND requestor = submitter";
2555 If you are maintaining legacy code you may see a different construct as
2556 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2561 This is a virtual operator that signals that the construct to its right side
2562 is a value to be passed to DBI. This is for example necessary when you want
2563 to write a where clause against an array (for RDBMS that support such
2564 datatypes). For example:
2567 array => { -value => [1, 2, 3] }
2572 $stmt = 'WHERE array = ?';
2573 @bind = ([1, 2, 3]);
2575 Note that if you were to simply say:
2581 the result would probably not be what you wanted:
2583 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2588 Finally, sometimes only literal SQL will do. To include a random snippet
2589 of SQL verbatim, you specify it as a scalar reference. Consider this only
2590 as a last resort. Usually there is a better way. For example:
2593 priority => { '<', 2 },
2594 requestor => { -in => \'(SELECT name FROM hitmen)' },
2599 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2602 Note that in this example, you only get one bind parameter back, since
2603 the verbatim SQL is passed as part of the statement.
2607 Never use untrusted input as a literal SQL argument - this is a massive
2608 security risk (there is no way to check literal snippets for SQL
2609 injections and other nastyness). If you need to deal with untrusted input
2610 use literal SQL with placeholders as described next.
2612 =head3 Literal SQL with placeholders and bind values (subqueries)
2614 If the literal SQL to be inserted has placeholders and bind values,
2615 use a reference to an arrayref (yes this is a double reference --
2616 not so common, but perfectly legal Perl). For example, to find a date
2617 in Postgres you can use something like this:
2620 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2625 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2628 Note that you must pass the bind values in the same format as they are returned
2629 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2630 to C<columns>, you must provide the bind values in the
2631 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2632 scalar value; most commonly the column name, but you can use any scalar value
2633 (including references and blessed references), L<SQL::Abstract> will simply
2634 pass it through intact. So if C<bindtype> is set to C<columns> the above
2635 example will look like:
2638 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2641 Literal SQL is especially useful for nesting parenthesized clauses in the
2642 main SQL query. Here is a first example:
2644 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2648 bar => \["IN ($sub_stmt)" => @sub_bind],
2653 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2654 WHERE c2 < ? AND c3 LIKE ?))";
2655 @bind = (1234, 100, "foo%");
2657 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2658 are expressed in the same way. Of course the C<$sub_stmt> and
2659 its associated bind values can be generated through a former call
2662 my ($sub_stmt, @sub_bind)
2663 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2664 c3 => {-like => "foo%"}});
2667 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2670 In the examples above, the subquery was used as an operator on a column;
2671 but the same principle also applies for a clause within the main C<%where>
2672 hash, like an EXISTS subquery:
2674 my ($sub_stmt, @sub_bind)
2675 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2676 my %where = ( -and => [
2678 \["EXISTS ($sub_stmt)" => @sub_bind],
2683 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2684 WHERE c1 = ? AND c2 > t0.c0))";
2688 Observe that the condition on C<c2> in the subquery refers to
2689 column C<t0.c0> of the main query: this is I<not> a bind
2690 value, so we have to express it through a scalar ref.
2691 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2692 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2693 what we wanted here.
2695 Finally, here is an example where a subquery is used
2696 for expressing unary negation:
2698 my ($sub_stmt, @sub_bind)
2699 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2700 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2702 lname => {like => '%son%'},
2703 \["NOT ($sub_stmt)" => @sub_bind],
2708 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2709 @bind = ('%son%', 10, 20)
2711 =head3 Deprecated usage of Literal SQL
2713 Below are some examples of archaic use of literal SQL. It is shown only as
2714 reference for those who deal with legacy code. Each example has a much
2715 better, cleaner and safer alternative that users should opt for in new code.
2721 my %where = ( requestor => \'IS NOT NULL' )
2723 $stmt = "WHERE requestor IS NOT NULL"
2725 This used to be the way of generating NULL comparisons, before the handling
2726 of C<undef> got formalized. For new code please use the superior syntax as
2727 described in L</Tests for NULL values>.
2731 my %where = ( requestor => \'= submitter' )
2733 $stmt = "WHERE requestor = submitter"
2735 This used to be the only way to compare columns. Use the superior L</-ident>
2736 method for all new code. For example an identifier declared in such a way
2737 will be properly quoted if L</quote_char> is properly set, while the legacy
2738 form will remain as supplied.
2742 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2744 $stmt = "WHERE completed > ? AND is_ready"
2745 @bind = ('2012-12-21')
2747 Using an empty string literal used to be the only way to express a boolean.
2748 For all new code please use the much more readable
2749 L<-bool|/Unary operators: bool> operator.
2755 These pages could go on for a while, since the nesting of the data
2756 structures this module can handle are pretty much unlimited (the
2757 module implements the C<WHERE> expansion as a recursive function
2758 internally). Your best bet is to "play around" with the module a
2759 little to see how the data structures behave, and choose the best
2760 format for your data based on that.
2762 And of course, all the values above will probably be replaced with
2763 variables gotten from forms or the command line. After all, if you
2764 knew everything ahead of time, you wouldn't have to worry about
2765 dynamically-generating SQL and could just hardwire it into your
2768 =head1 ORDER BY CLAUSES
2770 Some functions take an order by clause. This can either be a scalar (just a
2771 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2772 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2775 Given | Will Generate
2776 ---------------------------------------------------------------
2778 'colA' | ORDER BY colA
2780 [qw/colA colB/] | ORDER BY colA, colB
2782 {-asc => 'colA'} | ORDER BY colA ASC
2784 {-desc => 'colB'} | ORDER BY colB DESC
2786 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2788 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2790 \'colA DESC' | ORDER BY colA DESC
2792 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2793 | /* ...with $x bound to ? */
2796 { -asc => 'colA' }, | colA ASC,
2797 { -desc => [qw/colB/] }, | colB DESC,
2798 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2799 \'colE DESC', | colE DESC,
2800 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2801 ] | /* ...with $x bound to ? */
2802 ===============================================================
2806 =head1 SPECIAL OPERATORS
2808 my $sqlmaker = SQL::Abstract->new(special_ops => [
2812 my ($self, $field, $op, $arg) = @_;
2818 handler => 'method_name',
2822 A "special operator" is a SQL syntactic clause that can be
2823 applied to a field, instead of a usual binary operator.
2826 WHERE field IN (?, ?, ?)
2827 WHERE field BETWEEN ? AND ?
2828 WHERE MATCH(field) AGAINST (?, ?)
2830 Special operators IN and BETWEEN are fairly standard and therefore
2831 are builtin within C<SQL::Abstract> (as the overridable methods
2832 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2833 like the MATCH .. AGAINST example above which is specific to MySQL,
2834 you can write your own operator handlers - supply a C<special_ops>
2835 argument to the C<new> method. That argument takes an arrayref of
2836 operator definitions; each operator definition is a hashref with two
2843 the regular expression to match the operator
2847 Either a coderef or a plain scalar method name. In both cases
2848 the expected return is C<< ($sql, @bind) >>.
2850 When supplied with a method name, it is simply called on the
2851 L<SQL::Abstract> object as:
2853 $self->$method_name($field, $op, $arg)
2857 $field is the LHS of the operator
2858 $op is the part that matched the handler regex
2861 When supplied with a coderef, it is called as:
2863 $coderef->($self, $field, $op, $arg)
2868 For example, here is an implementation
2869 of the MATCH .. AGAINST syntax for MySQL
2871 my $sqlmaker = SQL::Abstract->new(special_ops => [
2873 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2874 {regex => qr/^match$/i,
2876 my ($self, $field, $op, $arg) = @_;
2877 $arg = [$arg] if not ref $arg;
2878 my $label = $self->_quote($field);
2879 my ($placeholder) = $self->_convert('?');
2880 my $placeholders = join ", ", (($placeholder) x @$arg);
2881 my $sql = $self->_sqlcase('match') . " ($label) "
2882 . $self->_sqlcase('against') . " ($placeholders) ";
2883 my @bind = $self->_bindtype($field, @$arg);
2884 return ($sql, @bind);
2891 =head1 UNARY OPERATORS
2893 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2897 my ($self, $op, $arg) = @_;
2903 handler => 'method_name',
2907 A "unary operator" is a SQL syntactic clause that can be
2908 applied to a field - the operator goes before the field
2910 You can write your own operator handlers - supply a C<unary_ops>
2911 argument to the C<new> method. That argument takes an arrayref of
2912 operator definitions; each operator definition is a hashref with two
2919 the regular expression to match the operator
2923 Either a coderef or a plain scalar method name. In both cases
2924 the expected return is C<< $sql >>.
2926 When supplied with a method name, it is simply called on the
2927 L<SQL::Abstract> object as:
2929 $self->$method_name($op, $arg)
2933 $op is the part that matched the handler regex
2934 $arg is the RHS or argument of the operator
2936 When supplied with a coderef, it is called as:
2938 $coderef->($self, $op, $arg)
2946 Thanks to some benchmarking by Mark Stosberg, it turns out that
2947 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2948 I must admit this wasn't an intentional design issue, but it's a
2949 byproduct of the fact that you get to control your C<DBI> handles
2952 To maximize performance, use a code snippet like the following:
2954 # prepare a statement handle using the first row
2955 # and then reuse it for the rest of the rows
2957 for my $href (@array_of_hashrefs) {
2958 $stmt ||= $sql->insert('table', $href);
2959 $sth ||= $dbh->prepare($stmt);
2960 $sth->execute($sql->values($href));
2963 The reason this works is because the keys in your C<$href> are sorted
2964 internally by B<SQL::Abstract>. Thus, as long as your data retains
2965 the same structure, you only have to generate the SQL the first time
2966 around. On subsequent queries, simply use the C<values> function provided
2967 by this module to return your values in the correct order.
2969 However this depends on the values having the same type - if, for
2970 example, the values of a where clause may either have values
2971 (resulting in sql of the form C<column = ?> with a single bind
2972 value), or alternatively the values might be C<undef> (resulting in
2973 sql of the form C<column IS NULL> with no bind value) then the
2974 caching technique suggested will not work.
2978 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2979 really like this part (I do, at least). Building up a complex query
2980 can be as simple as the following:
2987 use CGI::FormBuilder;
2990 my $form = CGI::FormBuilder->new(...);
2991 my $sql = SQL::Abstract->new;
2993 if ($form->submitted) {
2994 my $field = $form->field;
2995 my $id = delete $field->{id};
2996 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2999 Of course, you would still have to connect using C<DBI> to run the
3000 query, but the point is that if you make your form look like your
3001 table, the actual query script can be extremely simplistic.
3003 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3004 a fast interface to returning and formatting data. I frequently
3005 use these three modules together to write complex database query
3006 apps in under 50 lines.
3008 =head1 HOW TO CONTRIBUTE
3010 Contributions are always welcome, in all usable forms (we especially
3011 welcome documentation improvements). The delivery methods include git-
3012 or unified-diff formatted patches, GitHub pull requests, or plain bug
3013 reports either via RT or the Mailing list. Contributors are generally
3014 granted full access to the official repository after their first several
3015 patches pass successful review.
3017 This project is maintained in a git repository. The code and related tools are
3018 accessible at the following locations:
3022 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3024 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3026 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3028 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3034 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3035 Great care has been taken to preserve the I<published> behavior
3036 documented in previous versions in the 1.* family; however,
3037 some features that were previously undocumented, or behaved
3038 differently from the documentation, had to be changed in order
3039 to clarify the semantics. Hence, client code that was relying
3040 on some dark areas of C<SQL::Abstract> v1.*
3041 B<might behave differently> in v1.50.
3043 The main changes are:
3049 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3053 support for the { operator => \"..." } construct (to embed literal SQL)
3057 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3061 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3065 defensive programming: check arguments
3069 fixed bug with global logic, which was previously implemented
3070 through global variables yielding side-effects. Prior versions would
3071 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3072 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3073 Now this is interpreted
3074 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3079 fixed semantics of _bindtype on array args
3083 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3084 we just avoid shifting arrays within that tree.
3088 dropped the C<_modlogic> function
3092 =head1 ACKNOWLEDGEMENTS
3094 There are a number of individuals that have really helped out with
3095 this module. Unfortunately, most of them submitted bugs via CPAN
3096 so I have no idea who they are! But the people I do know are:
3098 Ash Berlin (order_by hash term support)
3099 Matt Trout (DBIx::Class support)
3100 Mark Stosberg (benchmarking)
3101 Chas Owens (initial "IN" operator support)
3102 Philip Collins (per-field SQL functions)
3103 Eric Kolve (hashref "AND" support)
3104 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3105 Dan Kubb (support for "quote_char" and "name_sep")
3106 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3107 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3108 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3109 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3110 Oliver Charles (support for "RETURNING" after "INSERT")
3116 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3120 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3122 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3124 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3125 While not an official support venue, C<DBIx::Class> makes heavy use of
3126 C<SQL::Abstract>, and as such list members there are very familiar with
3127 how to create queries.
3131 This module is free software; you may copy this under the same
3132 terms as perl itself (either the GNU General Public License or
3133 the Artistic License)