1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.87';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
187 $opt{expand_unary} = {};
190 -ident => '_expand_ident',
191 -value => '_expand_value',
192 -not => '_expand_not',
193 -bool => '_expand_bool',
194 -and => '_expand_andor',
195 -or => '_expand_andor',
198 $opt{render_op} = our $RENDER_OP;
201 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
205 return bless \%opt, $class;
208 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
209 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
211 sub _assert_pass_injection_guard {
212 if ($_[1] =~ $_[0]->{injection_guard}) {
213 my $class = ref $_[0];
214 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
215 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
216 . "{injection_guard} attribute to ${class}->new()"
221 #======================================================================
223 #======================================================================
227 my $table = $self->_table(shift);
228 my $data = shift || return;
231 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
232 my ($sql, @bind) = $self->$method($data);
233 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
235 if ($options->{returning}) {
236 my ($s, @b) = $self->_insert_returning($options);
241 return wantarray ? ($sql, @bind) : $sql;
244 # So that subclasses can override INSERT ... RETURNING separately from
245 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
246 sub _insert_returning { shift->_returning(@_) }
249 my ($self, $options) = @_;
251 my $f = $options->{returning};
253 my ($sql, @bind) = $self->render_aqt(
254 $self->_expand_maybe_list_expr($f, undef, -ident)
257 ? $self->_sqlcase(' returning ') . $sql
258 : ($self->_sqlcase(' returning ').$sql, @bind);
261 sub _insert_HASHREF { # explicit list of fields and then values
262 my ($self, $data) = @_;
264 my @fields = sort keys %$data;
266 my ($sql, @bind) = $self->_insert_values($data);
269 $_ = $self->_quote($_) foreach @fields;
270 $sql = "( ".join(", ", @fields).") ".$sql;
272 return ($sql, @bind);
275 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
276 my ($self, $data) = @_;
278 # no names (arrayref) so can't generate bindtype
279 $self->{bindtype} ne 'columns'
280 or belch "can't do 'columns' bindtype when called with arrayref";
282 my (@values, @all_bind);
283 foreach my $value (@$data) {
284 my ($values, @bind) = $self->_insert_value(undef, $value);
285 push @values, $values;
286 push @all_bind, @bind;
288 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
289 return ($sql, @all_bind);
292 sub _insert_ARRAYREFREF { # literal SQL with bind
293 my ($self, $data) = @_;
295 my ($sql, @bind) = @${$data};
296 $self->_assert_bindval_matches_bindtype(@bind);
298 return ($sql, @bind);
302 sub _insert_SCALARREF { # literal SQL without bind
303 my ($self, $data) = @_;
309 my ($self, $data) = @_;
311 my (@values, @all_bind);
312 foreach my $column (sort keys %$data) {
313 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
314 push @values, $values;
315 push @all_bind, @bind;
317 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
318 return ($sql, @all_bind);
322 my ($self, $column, $v) = @_;
324 return $self->render_aqt(
325 $self->_expand_insert_value($column, $v)
329 sub _expand_insert_value {
330 my ($self, $column, $v) = @_;
332 if (ref($v) eq 'ARRAY') {
333 if ($self->{array_datatypes}) {
334 return +{ -bind => [ $column, $v ] };
336 my ($sql, @bind) = @$v;
337 $self->_assert_bindval_matches_bindtype(@bind);
338 return +{ -literal => $v };
340 if (ref($v) eq 'HASH') {
341 if (grep !/^-/, keys %$v) {
342 belch "HASH ref as bind value in insert is not supported";
343 return +{ -bind => [ $column, $v ] };
347 return +{ -bind => [ $column, undef ] };
349 local our $Cur_Col_Meta = $column;
350 return $self->expand_expr($v);
355 #======================================================================
357 #======================================================================
362 my $table = $self->_table(shift);
363 my $data = shift || return;
367 # first build the 'SET' part of the sql statement
368 puke "Unsupported data type specified to \$sql->update"
369 unless ref $data eq 'HASH';
371 my ($sql, @all_bind) = $self->_update_set_values($data);
372 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
376 my($where_sql, @where_bind) = $self->where($where);
378 push @all_bind, @where_bind;
381 if ($options->{returning}) {
382 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
383 $sql .= $returning_sql;
384 push @all_bind, @returning_bind;
387 return wantarray ? ($sql, @all_bind) : $sql;
390 sub _update_set_values {
391 my ($self, $data) = @_;
393 return $self->render_aqt(
394 $self->_expand_update_set_values($data),
398 sub _expand_update_set_values {
399 my ($self, $data) = @_;
400 $self->_expand_maybe_list_expr( [
403 $set = { -bind => $_ } unless defined $set;
404 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
410 ? ($self->{array_datatypes}
411 ? [ $k, +{ -bind => [ $k, $v ] } ]
412 : [ $k, +{ -literal => $v } ])
414 local our $Cur_Col_Meta = $k;
415 [ $k, $self->_expand_expr($v) ]
422 # So that subclasses can override UPDATE ... RETURNING separately from
424 sub _update_returning { shift->_returning(@_) }
428 #======================================================================
430 #======================================================================
435 my $table = $self->_table(shift);
436 my $fields = shift || '*';
440 my ($fields_sql, @bind) = $self->_select_fields($fields);
442 my ($where_sql, @where_bind) = $self->where($where, $order);
443 push @bind, @where_bind;
445 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
446 $self->_sqlcase('from'), $table)
449 return wantarray ? ($sql, @bind) : $sql;
453 my ($self, $fields) = @_;
454 return $fields unless ref($fields);
455 return $self->render_aqt(
456 $self->_expand_maybe_list_expr($fields, undef, '-ident')
460 #======================================================================
462 #======================================================================
467 my $table = $self->_table(shift);
471 my($where_sql, @bind) = $self->where($where);
472 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
474 if ($options->{returning}) {
475 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
476 $sql .= $returning_sql;
477 push @bind, @returning_bind;
480 return wantarray ? ($sql, @bind) : $sql;
483 # So that subclasses can override DELETE ... RETURNING separately from
485 sub _delete_returning { shift->_returning(@_) }
489 #======================================================================
491 #======================================================================
495 # Finally, a separate routine just to handle WHERE clauses
497 my ($self, $where, $order) = @_;
499 local $self->{convert_where} = $self->{convert};
502 my ($sql, @bind) = defined($where)
503 ? $self->_recurse_where($where)
505 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
509 my ($order_sql, @order_bind) = $self->_order_by($order);
511 push @bind, @order_bind;
514 return wantarray ? ($sql, @bind) : $sql;
518 my ($self, $expr, $default_scalar_to) = @_;
519 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
520 $self->_expand_expr($expr);
524 my ($self, $aqt) = @_;
525 my ($k, $v, @rest) = %$aqt;
527 if (my $meth = $self->{render}{$k}) {
528 return $self->$meth($v);
530 die "notreached: $k";
534 my ($self, $expr) = @_;
535 $self->render_aqt($self->expand_expr($expr));
539 my ($self, $expr, $logic) = @_;
540 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
541 return undef unless defined($expr);
542 if (ref($expr) eq 'HASH') {
543 return undef unless my $kc = keys %$expr;
546 return $self->_expand_andor("-${logic}", $expr);
548 my ($key, $value) = %$expr;
549 if ($key =~ /^-/ and $key =~ s/ [_\s]? \d+ $//x ) {
550 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
551 . "You probably wanted ...-and => [ $key => COND1, $key => COND2 ... ]";
553 if (my $exp = $self->{expand}{$key}) {
554 return $self->$exp($key, $value);
556 return $self->_expand_expr_hashpair($key, $value, $logic);
558 if (ref($expr) eq 'ARRAY') {
559 my $logic = lc($logic || $self->{logic});
560 return $self->_expand_andor("-${logic}", $expr);
562 if (my $literal = is_literal_value($expr)) {
563 return +{ -literal => $literal };
565 if (!ref($expr) or Scalar::Util::blessed($expr)) {
566 if (my $d = our $Default_Scalar_To) {
567 return $self->_expand_expr({ $d => $expr });
569 return $self->_expand_value(-value => $expr);
574 sub _expand_expr_hashpair {
575 my ($self, $k, $v, $logic) = @_;
576 unless (defined($k) and length($k)) {
577 if (defined($k) and my $literal = is_literal_value($v)) {
578 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
579 return { -literal => $literal };
581 puke "Supplying an empty left hand side argument is not supported";
584 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
586 # DBIx::Class requires a nest warning to be emitted once but the private
587 # method it overrode to do so no longer exists
588 if ($self->{is_dbic_sqlmaker}) {
589 unless (our $Nest_Warned) {
591 "-nest in search conditions is deprecated, you most probably wanted:\n"
592 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
597 return $self->_expand_expr($v);
599 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
602 $self->_expand_expr({ "-${rest}", $v }, $logic)
607 $op =~ s/^-// if length($op) > 1;
609 # top level special ops are illegal in general
610 # note that, arguably, if it makes no sense at top level, it also
611 # makes no sense on the other side of an = sign or similar but DBIC
612 # gets disappointingly upset if I disallow it
614 (our $Expand_Depth) == 1
615 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
617 puke "Illegal use of top-level '-$op'"
619 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
620 return { -op => [ $op, $v ] };
623 if ($self->{render}{$k}) {
629 and (keys %$v)[0] =~ /^-/
631 my ($func) = $k =~ /^-(.*)$/;
632 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
633 return +{ -op => [ $func, $self->_expand_expr($v) ] };
635 return +{ -func => [ $func, $self->_expand_expr($v) ] };
637 if (!ref($v) or is_literal_value($v)) {
638 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
645 and exists $v->{-value}
646 and not defined $v->{-value}
649 return $self->_expand_expr({ $k => { $self->{cmp} => undef } });
651 if (!ref($v) or Scalar::Util::blessed($v)) {
652 my $d = our $Default_Scalar_To;
656 $self->_expand_ident(-ident => $k),
658 ? $self->_expand_expr($d => $v)
659 : { -bind => [ $k, $v ] }
664 if (ref($v) eq 'HASH') {
668 map $self->_expand_expr({ $k => { $_ => $v->{$_} } }),
672 return undef unless keys %$v;
674 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
675 $self->_assert_pass_injection_guard($op);
676 if ($op =~ s/ [_\s]? \d+ $//x ) {
677 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
678 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
680 if ($op =~ /^(?:not )?between$/) {
681 local our $Cur_Col_Meta = $k;
682 my @rhs = map $self->_expand_expr($_),
683 ref($vv) eq 'ARRAY' ? @$vv : $vv;
685 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
687 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
689 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
693 $self->_expand_ident(-ident => $k),
697 if ($op =~ /^(?:not )?in$/) {
698 if (my $literal = is_literal_value($vv)) {
699 my ($sql, @bind) = @$literal;
700 my $opened_sql = $self->_open_outer_paren($sql);
702 $op, $self->_expand_ident(-ident => $k),
703 [ { -literal => [ $opened_sql, @bind ] } ]
707 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
708 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
709 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
710 . 'will emit the logically correct SQL instead of raising this exception)'
712 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
714 my @rhs = map $self->_expand_expr($_),
715 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
716 map { defined($_) ? $_: puke($undef_err) }
717 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
718 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
722 $self->_expand_ident(-ident => $k),
726 if ($op eq 'ident') {
727 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
728 puke "-$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
732 $self->_expand_ident(-ident => $k),
733 $self->_expand_ident(-ident => $vv),
736 if ($op eq 'value') {
737 return $self->_expand_expr({ $k, undef }) unless defined($vv);
740 $self->_expand_ident(-ident => $k),
741 { -bind => [ $k, $vv ] }
744 if ($op =~ /^is(?: not)?$/) {
745 puke "$op can only take undef as argument"
749 and exists($vv->{-value})
750 and !defined($vv->{-value})
752 return +{ -op => [ $op.' null', $self->_expand_ident(-ident => $k) ] };
754 if ($op =~ /^(and|or)$/) {
755 if (ref($vv) eq 'HASH') {
758 map $self->_expand_expr({ $k, { $_ => $vv->{$_} } }),
763 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
764 return { -op => [ $op, $self->_expand_ident(-ident => $k), $vv ] };
766 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
769 $self->_expand_ident(-ident => $k),
770 { -op => [ $op, $vv ] }
773 if (ref($vv) eq 'ARRAY') {
774 my ($logic, @values) = (
775 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
780 $op =~ $self->{inequality_op}
781 or $op =~ $self->{not_like_op}
783 if (lc($logic) eq '-or' and @values > 1) {
784 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
785 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
786 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
791 # try to DWIM on equality operators
793 $op =~ $self->{equality_op} ? $self->sqlfalse
794 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
795 : $op =~ $self->{inequality_op} ? $self->sqltrue
796 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
797 : puke "operator '$op' applied on an empty array (field '$k')";
801 map $self->_expand_expr({ $k => { $vk => $_ } }),
809 and exists $vv->{-value}
810 and not defined $vv->{-value}
814 $op =~ /^not$/i ? 'is not' # legacy
815 : $op =~ $self->{equality_op} ? 'is'
816 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
817 : $op =~ $self->{inequality_op} ? 'is not'
818 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
819 : puke "unexpected operator '$op' with undef operand";
820 return +{ -op => [ $is.' null', $self->_expand_ident(-ident => $k) ] };
822 local our $Cur_Col_Meta = $k;
825 $self->_expand_ident(-ident => $k),
826 $self->_expand_expr($vv)
829 if (ref($v) eq 'ARRAY') {
830 return $self->sqlfalse unless @$v;
831 $self->_debug("ARRAY($k) means distribute over elements");
833 $v->[0] =~ /^-(and|or)$/i
834 ? shift(@{$v = [ @$v ]})
835 : '-'.($self->{logic} || 'or')
837 return $self->_expand_expr({
838 $this_logic => [ map +{ $k => $_ }, @$v ]
841 if (my $literal = is_literal_value($v)) {
843 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
846 my ($sql, @bind) = @$literal;
847 if ($self->{bindtype} eq 'columns') {
849 $self->_assert_bindval_matches_bindtype($_);
852 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
858 my ($self, undef, $body) = @_;
859 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
860 ref($body) ? @$body : $body;
861 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
862 unless ($self->{quote_char}) {
863 $self->_assert_pass_injection_guard($_) for @parts;
865 return +{ -ident => \@parts };
869 +{ -bind => [ our $Cur_Col_Meta, $_[2] ] };
873 +{ -op => [ 'not', $_[0]->_expand_expr($_[2]) ] };
877 my ($self, undef, $v) = @_;
879 return $self->_expand_expr($v);
881 puke "-bool => undef not supported" unless defined($v);
882 return $self->_expand_ident(-ident => $v);
886 my ($self, $k, $v) = @_;
887 my ($logic) = $k =~ /^-(.*)$/;
888 if (ref($v) eq 'HASH') {
891 map $self->_expand_expr({ $_ => $v->{$_} }, $logic),
895 if (ref($v) eq 'ARRAY') {
896 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
899 (ref($_) eq 'ARRAY' and @$_)
900 or (ref($_) eq 'HASH' and %$_)
906 while (my ($el) = splice @expr, 0, 1) {
907 puke "Supplying an empty left hand side argument is not supported in array-pairs"
908 unless defined($el) and length($el);
909 my $elref = ref($el);
911 local our $Expand_Depth = 0;
912 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
913 } elsif ($elref eq 'ARRAY') {
914 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
915 } elsif (my $l = is_literal_value($el)) {
916 push @res, { -literal => $l };
917 } elsif ($elref eq 'HASH') {
918 local our $Expand_Depth = 0;
919 push @res, grep defined, $self->_expand_expr($el) if %$el;
925 # return $res[0] if @res == 1;
926 return { -op => [ $logic, @res ] };
932 my ($self, $where, $logic) = @_;
934 # Special case: top level simple string treated as literal
936 my $where_exp = (ref($where)
937 ? $self->_expand_expr($where, $logic)
938 : { -literal => [ $where ] });
940 # dispatch expanded expression
942 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
943 # DBIx::Class used to call _recurse_where in scalar context
944 # something else might too...
946 return ($sql, @bind);
949 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
955 my ($self, $ident) = @_;
957 return $self->_convert($self->_quote($ident));
961 my ($self, $list) = @_;
962 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
963 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
967 my ($self, $rest) = @_;
968 my ($func, @args) = @$rest;
972 push @arg_sql, shift @x;
974 } map [ $self->render_aqt($_) ], @args;
975 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
979 my ($self, $bind) = @_;
980 return ($self->_convert('?'), $self->_bindtype(@$bind));
983 sub _render_literal {
984 my ($self, $literal) = @_;
985 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
991 my ($self, $op, $args) = @_;
992 my ($left, $low, $high) = @$args;
993 my ($rhsql, @rhbind) = do {
995 puke "Single arg to between must be a literal"
996 unless $low->{-literal};
999 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
1000 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
1001 @{$l}[1..$#$l], @{$h}[1..$#$h])
1004 my ($lhsql, @lhbind) = $self->render_aqt($left);
1006 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
1009 }), 'between', 'not between'),
1011 my ($self, $op, $args) = @_;
1012 my ($lhs, $rhs) = @$args;
1015 my ($sql, @bind) = $self->render_aqt($_);
1016 push @in_bind, @bind;
1019 my ($lhsql, @lbind) = $self->render_aqt($lhs);
1021 $lhsql.' '.$self->_sqlcase($op).' ( '
1022 .join(', ', @in_sql)
1026 }), 'in', 'not in'),
1027 (map +($_ => '_render_unop_postfix'),
1028 'is null', 'is not null', 'asc', 'desc',
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, $v) = @_;
1085 my ($expr_sql, @bind) = $self->render_aqt($v->[0]);
1086 my $op_sql = $self->_sqlcase($op);
1087 return ($expr_sql.' '.$op_sql, @bind);
1090 # Some databases (SQLite) treat col IN (1, 2) different from
1091 # col IN ( (1, 2) ). Use this to strip all outer parens while
1092 # adding them back in the corresponding method
1093 sub _open_outer_paren {
1094 my ($self, $sql) = @_;
1096 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1098 # there are closing parens inside, need the heavy duty machinery
1099 # to reevaluate the extraction starting from $sql (full reevaluation)
1100 if ($inner =~ /\)/) {
1101 require Text::Balanced;
1103 my (undef, $remainder) = do {
1104 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1106 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1109 # the entire expression needs to be a balanced bracketed thing
1110 # (after an extract no remainder sans trailing space)
1111 last if defined $remainder and $remainder =~ /\S/;
1121 #======================================================================
1123 #======================================================================
1125 sub _expand_order_by {
1126 my ($self, $arg) = @_;
1128 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1130 my $expander = sub {
1131 my ($self, $dir, $expr) = @_;
1132 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1133 foreach my $arg (@to_expand) {
1137 and grep /^-(asc|desc)$/, keys %$arg
1139 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1143 defined($dir) ? { -op => [ $dir =~ /^-?(.*)$/ ,=> $_ ] } : $_
1145 map $self->expand_expr($_, -ident),
1146 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1147 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1150 local @{$self->{expand}}{qw(-asc -desc)} = (($expander) x 2);
1152 return $self->$expander(undef, $arg);
1156 my ($self, $arg) = @_;
1158 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1160 my ($sql, @bind) = $self->render_aqt($expanded);
1162 return '' unless length($sql);
1164 my $final_sql = $self->_sqlcase(' order by ').$sql;
1166 return wantarray ? ($final_sql, @bind) : $final_sql;
1169 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1171 sub _order_by_chunks {
1172 my ($self, $arg) = @_;
1174 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1176 return $self->_chunkify_order_by($expanded);
1179 sub _chunkify_order_by {
1180 my ($self, $expanded) = @_;
1182 return grep length, $self->render_aqt($expanded)
1183 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1186 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1187 return map $self->_chunkify_order_by($_), @$l;
1189 return [ $self->render_aqt($_) ];
1193 #======================================================================
1194 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1195 #======================================================================
1201 $self->_expand_maybe_list_expr($from, undef, -ident)
1206 #======================================================================
1208 #======================================================================
1210 sub _expand_maybe_list_expr {
1211 my ($self, $expr, $logic, $default) = @_;
1213 if (ref($expr) eq 'ARRAY') {
1215 map $self->expand_expr($_, $default), @$expr
1222 return $self->expand_expr($e, $default);
1225 # highly optimized, as it's called way too often
1227 # my ($self, $label) = @_;
1229 return '' unless defined $_[1];
1230 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1231 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1233 unless ($_[0]->{quote_char}) {
1234 if (ref($_[1]) eq 'ARRAY') {
1235 return join($_[0]->{name_sep}||'.', @{$_[1]});
1237 $_[0]->_assert_pass_injection_guard($_[1]);
1242 my $qref = ref $_[0]->{quote_char};
1244 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1245 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1246 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1248 my $esc = $_[0]->{escape_char} || $r;
1250 # parts containing * are naturally unquoted
1252 $_[0]->{name_sep}||'',
1256 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1258 (ref($_[1]) eq 'ARRAY'
1262 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1270 # Conversion, if applicable
1272 #my ($self, $arg) = @_;
1273 if ($_[0]->{convert_where}) {
1274 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1281 #my ($self, $col, @vals) = @_;
1282 # called often - tighten code
1283 return $_[0]->{bindtype} eq 'columns'
1284 ? map {[$_[1], $_]} @_[2 .. $#_]
1289 # Dies if any element of @bind is not in [colname => value] format
1290 # if bindtype is 'columns'.
1291 sub _assert_bindval_matches_bindtype {
1292 # my ($self, @bind) = @_;
1294 if ($self->{bindtype} eq 'columns') {
1296 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1297 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1303 sub _join_sql_clauses {
1304 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1306 if (@$clauses_aref > 1) {
1307 my $join = " " . $self->_sqlcase($logic) . " ";
1308 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1309 return ($sql, @$bind_aref);
1311 elsif (@$clauses_aref) {
1312 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1315 return (); # if no SQL, ignore @$bind_aref
1320 # Fix SQL case, if so requested
1322 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1323 # don't touch the argument ... crooked logic, but let's not change it!
1324 return $_[0]->{case} ? $_[1] : uc($_[1]);
1328 #======================================================================
1329 # DISPATCHING FROM REFKIND
1330 #======================================================================
1333 my ($self, $data) = @_;
1335 return 'UNDEF' unless defined $data;
1337 # blessed objects are treated like scalars
1338 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1340 return 'SCALAR' unless $ref;
1343 while ($ref eq 'REF') {
1345 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1349 return ($ref||'SCALAR') . ('REF' x $n_steps);
1353 my ($self, $data) = @_;
1354 my @try = ($self->_refkind($data));
1355 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1356 push @try, 'FALLBACK';
1360 sub _METHOD_FOR_refkind {
1361 my ($self, $meth_prefix, $data) = @_;
1364 for (@{$self->_try_refkind($data)}) {
1365 $method = $self->can($meth_prefix."_".$_)
1369 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1373 sub _SWITCH_refkind {
1374 my ($self, $data, $dispatch_table) = @_;
1377 for (@{$self->_try_refkind($data)}) {
1378 $coderef = $dispatch_table->{$_}
1382 puke "no dispatch entry for ".$self->_refkind($data)
1391 #======================================================================
1392 # VALUES, GENERATE, AUTOLOAD
1393 #======================================================================
1395 # LDNOTE: original code from nwiger, didn't touch code in that section
1396 # I feel the AUTOLOAD stuff should not be the default, it should
1397 # only be activated on explicit demand by user.
1401 my $data = shift || return;
1402 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1403 unless ref $data eq 'HASH';
1406 foreach my $k (sort keys %$data) {
1407 my $v = $data->{$k};
1408 $self->_SWITCH_refkind($v, {
1410 if ($self->{array_datatypes}) { # array datatype
1411 push @all_bind, $self->_bindtype($k, $v);
1413 else { # literal SQL with bind
1414 my ($sql, @bind) = @$v;
1415 $self->_assert_bindval_matches_bindtype(@bind);
1416 push @all_bind, @bind;
1419 ARRAYREFREF => sub { # literal SQL with bind
1420 my ($sql, @bind) = @${$v};
1421 $self->_assert_bindval_matches_bindtype(@bind);
1422 push @all_bind, @bind;
1424 SCALARREF => sub { # literal SQL without bind
1426 SCALAR_or_UNDEF => sub {
1427 push @all_bind, $self->_bindtype($k, $v);
1438 my(@sql, @sqlq, @sqlv);
1442 if ($ref eq 'HASH') {
1443 for my $k (sort keys %$_) {
1446 my $label = $self->_quote($k);
1447 if ($r eq 'ARRAY') {
1448 # literal SQL with bind
1449 my ($sql, @bind) = @$v;
1450 $self->_assert_bindval_matches_bindtype(@bind);
1451 push @sqlq, "$label = $sql";
1453 } elsif ($r eq 'SCALAR') {
1454 # literal SQL without bind
1455 push @sqlq, "$label = $$v";
1457 push @sqlq, "$label = ?";
1458 push @sqlv, $self->_bindtype($k, $v);
1461 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1462 } elsif ($ref eq 'ARRAY') {
1463 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1466 if ($r eq 'ARRAY') { # literal SQL with bind
1467 my ($sql, @bind) = @$v;
1468 $self->_assert_bindval_matches_bindtype(@bind);
1471 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1472 # embedded literal SQL
1479 push @sql, '(' . join(', ', @sqlq) . ')';
1480 } elsif ($ref eq 'SCALAR') {
1484 # strings get case twiddled
1485 push @sql, $self->_sqlcase($_);
1489 my $sql = join ' ', @sql;
1491 # this is pretty tricky
1492 # if ask for an array, return ($stmt, @bind)
1493 # otherwise, s/?/shift @sqlv/ to put it inline
1495 return ($sql, @sqlv);
1497 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1498 ref $d ? $d->[1] : $d/e;
1507 # This allows us to check for a local, then _form, attr
1509 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1510 return $self->generate($name, @_);
1521 SQL::Abstract - Generate SQL from Perl data structures
1527 my $sql = SQL::Abstract->new;
1529 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1531 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1533 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1535 my($stmt, @bind) = $sql->delete($table, \%where);
1537 # Then, use these in your DBI statements
1538 my $sth = $dbh->prepare($stmt);
1539 $sth->execute(@bind);
1541 # Just generate the WHERE clause
1542 my($stmt, @bind) = $sql->where(\%where, $order);
1544 # Return values in the same order, for hashed queries
1545 # See PERFORMANCE section for more details
1546 my @bind = $sql->values(\%fieldvals);
1550 This module was inspired by the excellent L<DBIx::Abstract>.
1551 However, in using that module I found that what I really wanted
1552 to do was generate SQL, but still retain complete control over my
1553 statement handles and use the DBI interface. So, I set out to
1554 create an abstract SQL generation module.
1556 While based on the concepts used by L<DBIx::Abstract>, there are
1557 several important differences, especially when it comes to WHERE
1558 clauses. I have modified the concepts used to make the SQL easier
1559 to generate from Perl data structures and, IMO, more intuitive.
1560 The underlying idea is for this module to do what you mean, based
1561 on the data structures you provide it. The big advantage is that
1562 you don't have to modify your code every time your data changes,
1563 as this module figures it out.
1565 To begin with, an SQL INSERT is as easy as just specifying a hash
1566 of C<key=value> pairs:
1569 name => 'Jimbo Bobson',
1570 phone => '123-456-7890',
1571 address => '42 Sister Lane',
1572 city => 'St. Louis',
1573 state => 'Louisiana',
1576 The SQL can then be generated with this:
1578 my($stmt, @bind) = $sql->insert('people', \%data);
1580 Which would give you something like this:
1582 $stmt = "INSERT INTO people
1583 (address, city, name, phone, state)
1584 VALUES (?, ?, ?, ?, ?)";
1585 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1586 '123-456-7890', 'Louisiana');
1588 These are then used directly in your DBI code:
1590 my $sth = $dbh->prepare($stmt);
1591 $sth->execute(@bind);
1593 =head2 Inserting and Updating Arrays
1595 If your database has array types (like for example Postgres),
1596 activate the special option C<< array_datatypes => 1 >>
1597 when creating the C<SQL::Abstract> object.
1598 Then you may use an arrayref to insert and update database array types:
1600 my $sql = SQL::Abstract->new(array_datatypes => 1);
1602 planets => [qw/Mercury Venus Earth Mars/]
1605 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1609 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1611 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1614 =head2 Inserting and Updating SQL
1616 In order to apply SQL functions to elements of your C<%data> you may
1617 specify a reference to an arrayref for the given hash value. For example,
1618 if you need to execute the Oracle C<to_date> function on a value, you can
1619 say something like this:
1623 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1626 The first value in the array is the actual SQL. Any other values are
1627 optional and would be included in the bind values array. This gives
1630 my($stmt, @bind) = $sql->insert('people', \%data);
1632 $stmt = "INSERT INTO people (name, date_entered)
1633 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1634 @bind = ('Bill', '03/02/2003');
1636 An UPDATE is just as easy, all you change is the name of the function:
1638 my($stmt, @bind) = $sql->update('people', \%data);
1640 Notice that your C<%data> isn't touched; the module will generate
1641 the appropriately quirky SQL for you automatically. Usually you'll
1642 want to specify a WHERE clause for your UPDATE, though, which is
1643 where handling C<%where> hashes comes in handy...
1645 =head2 Complex where statements
1647 This module can generate pretty complicated WHERE statements
1648 easily. For example, simple C<key=value> pairs are taken to mean
1649 equality, and if you want to see if a field is within a set
1650 of values, you can use an arrayref. Let's say we wanted to
1651 SELECT some data based on this criteria:
1654 requestor => 'inna',
1655 worker => ['nwiger', 'rcwe', 'sfz'],
1656 status => { '!=', 'completed' }
1659 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1661 The above would give you something like this:
1663 $stmt = "SELECT * FROM tickets WHERE
1664 ( requestor = ? ) AND ( status != ? )
1665 AND ( worker = ? OR worker = ? OR worker = ? )";
1666 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1668 Which you could then use in DBI code like so:
1670 my $sth = $dbh->prepare($stmt);
1671 $sth->execute(@bind);
1677 The methods are simple. There's one for every major SQL operation,
1678 and a constructor you use first. The arguments are specified in a
1679 similar order for each method (table, then fields, then a where
1680 clause) to try and simplify things.
1682 =head2 new(option => 'value')
1684 The C<new()> function takes a list of options and values, and returns
1685 a new B<SQL::Abstract> object which can then be used to generate SQL
1686 through the methods below. The options accepted are:
1692 If set to 'lower', then SQL will be generated in all lowercase. By
1693 default SQL is generated in "textbook" case meaning something like:
1695 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1697 Any setting other than 'lower' is ignored.
1701 This determines what the default comparison operator is. By default
1702 it is C<=>, meaning that a hash like this:
1704 %where = (name => 'nwiger', email => 'nate@wiger.org');
1706 Will generate SQL like this:
1708 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1710 However, you may want loose comparisons by default, so if you set
1711 C<cmp> to C<like> you would get SQL such as:
1713 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1715 You can also override the comparison on an individual basis - see
1716 the huge section on L</"WHERE CLAUSES"> at the bottom.
1718 =item sqltrue, sqlfalse
1720 Expressions for inserting boolean values within SQL statements.
1721 By default these are C<1=1> and C<1=0>. They are used
1722 by the special operators C<-in> and C<-not_in> for generating
1723 correct SQL even when the argument is an empty array (see below).
1727 This determines the default logical operator for multiple WHERE
1728 statements in arrays or hashes. If absent, the default logic is "or"
1729 for arrays, and "and" for hashes. This means that a WHERE
1733 event_date => {'>=', '2/13/99'},
1734 event_date => {'<=', '4/24/03'},
1737 will generate SQL like this:
1739 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1741 This is probably not what you want given this query, though (look
1742 at the dates). To change the "OR" to an "AND", simply specify:
1744 my $sql = SQL::Abstract->new(logic => 'and');
1746 Which will change the above C<WHERE> to:
1748 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1750 The logic can also be changed locally by inserting
1751 a modifier in front of an arrayref:
1753 @where = (-and => [event_date => {'>=', '2/13/99'},
1754 event_date => {'<=', '4/24/03'} ]);
1756 See the L</"WHERE CLAUSES"> section for explanations.
1760 This will automatically convert comparisons using the specified SQL
1761 function for both column and value. This is mostly used with an argument
1762 of C<upper> or C<lower>, so that the SQL will have the effect of
1763 case-insensitive "searches". For example, this:
1765 $sql = SQL::Abstract->new(convert => 'upper');
1766 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1768 Will turn out the following SQL:
1770 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1772 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1773 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1774 not validate this option; it will just pass through what you specify verbatim).
1778 This is a kludge because many databases suck. For example, you can't
1779 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1780 Instead, you have to use C<bind_param()>:
1782 $sth->bind_param(1, 'reg data');
1783 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1785 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1786 which loses track of which field each slot refers to. Fear not.
1788 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1789 Currently, you can specify either C<normal> (default) or C<columns>. If you
1790 specify C<columns>, you will get an array that looks like this:
1792 my $sql = SQL::Abstract->new(bindtype => 'columns');
1793 my($stmt, @bind) = $sql->insert(...);
1796 [ 'column1', 'value1' ],
1797 [ 'column2', 'value2' ],
1798 [ 'column3', 'value3' ],
1801 You can then iterate through this manually, using DBI's C<bind_param()>.
1803 $sth->prepare($stmt);
1806 my($col, $data) = @$_;
1807 if ($col eq 'details' || $col eq 'comments') {
1808 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1809 } elsif ($col eq 'image') {
1810 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1812 $sth->bind_param($i, $data);
1816 $sth->execute; # execute without @bind now
1818 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1819 Basically, the advantage is still that you don't have to care which fields
1820 are or are not included. You could wrap that above C<for> loop in a simple
1821 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1822 get a layer of abstraction over manual SQL specification.
1824 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1825 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1826 will expect the bind values in this format.
1830 This is the character that a table or column name will be quoted
1831 with. By default this is an empty string, but you could set it to
1832 the character C<`>, to generate SQL like this:
1834 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1836 Alternatively, you can supply an array ref of two items, the first being the left
1837 hand quote character, and the second the right hand quote character. For
1838 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1839 that generates SQL like this:
1841 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1843 Quoting is useful if you have tables or columns names that are reserved
1844 words in your database's SQL dialect.
1848 This is the character that will be used to escape L</quote_char>s appearing
1849 in an identifier before it has been quoted.
1851 The parameter default in case of a single L</quote_char> character is the quote
1854 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1855 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1856 of the B<opening (left)> L</quote_char> within the identifier are currently left
1857 untouched. The default for opening-closing-style quotes may change in future
1858 versions, thus you are B<strongly encouraged> to specify the escape character
1863 This is the character that separates a table and column name. It is
1864 necessary to specify this when the C<quote_char> option is selected,
1865 so that tables and column names can be individually quoted like this:
1867 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1869 =item injection_guard
1871 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1872 column name specified in a query structure. This is a safety mechanism to avoid
1873 injection attacks when mishandling user input e.g.:
1875 my %condition_as_column_value_pairs = get_values_from_user();
1876 $sqla->select( ... , \%condition_as_column_value_pairs );
1878 If the expression matches an exception is thrown. Note that literal SQL
1879 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1881 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1883 =item array_datatypes
1885 When this option is true, arrayrefs in INSERT or UPDATE are
1886 interpreted as array datatypes and are passed directly
1888 When this option is false, arrayrefs are interpreted
1889 as literal SQL, just like refs to arrayrefs
1890 (but this behavior is for backwards compatibility; when writing
1891 new queries, use the "reference to arrayref" syntax
1897 Takes a reference to a list of "special operators"
1898 to extend the syntax understood by L<SQL::Abstract>.
1899 See section L</"SPECIAL OPERATORS"> for details.
1903 Takes a reference to a list of "unary operators"
1904 to extend the syntax understood by L<SQL::Abstract>.
1905 See section L</"UNARY OPERATORS"> for details.
1911 =head2 insert($table, \@values || \%fieldvals, \%options)
1913 This is the simplest function. You simply give it a table name
1914 and either an arrayref of values or hashref of field/value pairs.
1915 It returns an SQL INSERT statement and a list of bind values.
1916 See the sections on L</"Inserting and Updating Arrays"> and
1917 L</"Inserting and Updating SQL"> for information on how to insert
1918 with those data types.
1920 The optional C<\%options> hash reference may contain additional
1921 options to generate the insert SQL. Currently supported options
1928 Takes either a scalar of raw SQL fields, or an array reference of
1929 field names, and adds on an SQL C<RETURNING> statement at the end.
1930 This allows you to return data generated by the insert statement
1931 (such as row IDs) without performing another C<SELECT> statement.
1932 Note, however, this is not part of the SQL standard and may not
1933 be supported by all database engines.
1937 =head2 update($table, \%fieldvals, \%where, \%options)
1939 This takes a table, hashref of field/value pairs, and an optional
1940 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1942 See the sections on L</"Inserting and Updating Arrays"> and
1943 L</"Inserting and Updating SQL"> for information on how to insert
1944 with those data types.
1946 The optional C<\%options> hash reference may contain additional
1947 options to generate the update SQL. Currently supported options
1954 See the C<returning> option to
1955 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1959 =head2 select($source, $fields, $where, $order)
1961 This returns a SQL SELECT statement and associated list of bind values, as
1962 specified by the arguments:
1968 Specification of the 'FROM' part of the statement.
1969 The argument can be either a plain scalar (interpreted as a table
1970 name, will be quoted), or an arrayref (interpreted as a list
1971 of table names, joined by commas, quoted), or a scalarref
1972 (literal SQL, not quoted).
1976 Specification of the list of fields to retrieve from
1978 The argument can be either an arrayref (interpreted as a list
1979 of field names, will be joined by commas and quoted), or a
1980 plain scalar (literal SQL, not quoted).
1981 Please observe that this API is not as flexible as that of
1982 the first argument C<$source>, for backwards compatibility reasons.
1986 Optional argument to specify the WHERE part of the query.
1987 The argument is most often a hashref, but can also be
1988 an arrayref or plain scalar --
1989 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1993 Optional argument to specify the ORDER BY part of the query.
1994 The argument can be a scalar, a hashref or an arrayref
1995 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2001 =head2 delete($table, \%where, \%options)
2003 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2004 It returns an SQL DELETE statement and list of bind values.
2006 The optional C<\%options> hash reference may contain additional
2007 options to generate the delete SQL. Currently supported options
2014 See the C<returning> option to
2015 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2019 =head2 where(\%where, $order)
2021 This is used to generate just the WHERE clause. For example,
2022 if you have an arbitrary data structure and know what the
2023 rest of your SQL is going to look like, but want an easy way
2024 to produce a WHERE clause, use this. It returns an SQL WHERE
2025 clause and list of bind values.
2028 =head2 values(\%data)
2030 This just returns the values from the hash C<%data>, in the same
2031 order that would be returned from any of the other above queries.
2032 Using this allows you to markedly speed up your queries if you
2033 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2035 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2037 Warning: This is an experimental method and subject to change.
2039 This returns arbitrarily generated SQL. It's a really basic shortcut.
2040 It will return two different things, depending on return context:
2042 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2043 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2045 These would return the following:
2047 # First calling form
2048 $stmt = "CREATE TABLE test (?, ?)";
2049 @bind = (field1, field2);
2051 # Second calling form
2052 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2054 Depending on what you're trying to do, it's up to you to choose the correct
2055 format. In this example, the second form is what you would want.
2059 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2063 ALTER SESSION SET nls_date_format = 'MM/YY'
2065 You get the idea. Strings get their case twiddled, but everything
2066 else remains verbatim.
2068 =head1 EXPORTABLE FUNCTIONS
2070 =head2 is_plain_value
2072 Determines if the supplied argument is a plain value as understood by this
2077 =item * The value is C<undef>
2079 =item * The value is a non-reference
2081 =item * The value is an object with stringification overloading
2083 =item * The value is of the form C<< { -value => $anything } >>
2087 On failure returns C<undef>, on success returns a B<scalar> reference
2088 to the original supplied argument.
2094 The stringification overloading detection is rather advanced: it takes
2095 into consideration not only the presence of a C<""> overload, but if that
2096 fails also checks for enabled
2097 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2098 on either C<0+> or C<bool>.
2100 Unfortunately testing in the field indicates that this
2101 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2102 but only when very large numbers of stringifying objects are involved.
2103 At the time of writing ( Sep 2014 ) there is no clear explanation of
2104 the direct cause, nor is there a manageably small test case that reliably
2105 reproduces the problem.
2107 If you encounter any of the following exceptions in B<random places within
2108 your application stack> - this module may be to blame:
2110 Operation "ne": no method found,
2111 left argument in overloaded package <something>,
2112 right argument in overloaded package <something>
2116 Stub found while resolving method "???" overloading """" in package <something>
2118 If you fall victim to the above - please attempt to reduce the problem
2119 to something that could be sent to the L<SQL::Abstract developers
2120 |DBIx::Class/GETTING HELP/SUPPORT>
2121 (either publicly or privately). As a workaround in the meantime you can
2122 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2123 value, which will most likely eliminate your problem (at the expense of
2124 not being able to properly detect exotic forms of stringification).
2126 This notice and environment variable will be removed in a future version,
2127 as soon as the underlying problem is found and a reliable workaround is
2132 =head2 is_literal_value
2134 Determines if the supplied argument is a literal value as understood by this
2139 =item * C<\$sql_string>
2141 =item * C<\[ $sql_string, @bind_values ]>
2145 On failure returns C<undef>, on success returns an B<array> reference
2146 containing the unpacked version of the supplied literal SQL and bind values.
2148 =head1 WHERE CLAUSES
2152 This module uses a variation on the idea from L<DBIx::Abstract>. It
2153 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2154 module is that things in arrays are OR'ed, and things in hashes
2157 The easiest way to explain is to show lots of examples. After
2158 each C<%where> hash shown, it is assumed you used:
2160 my($stmt, @bind) = $sql->where(\%where);
2162 However, note that the C<%where> hash can be used directly in any
2163 of the other functions as well, as described above.
2165 =head2 Key-value pairs
2167 So, let's get started. To begin, a simple hash:
2171 status => 'completed'
2174 Is converted to SQL C<key = val> statements:
2176 $stmt = "WHERE user = ? AND status = ?";
2177 @bind = ('nwiger', 'completed');
2179 One common thing I end up doing is having a list of values that
2180 a field can be in. To do this, simply specify a list inside of
2185 status => ['assigned', 'in-progress', 'pending'];
2188 This simple code will create the following:
2190 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2191 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2193 A field associated to an empty arrayref will be considered a
2194 logical false and will generate 0=1.
2196 =head2 Tests for NULL values
2198 If the value part is C<undef> then this is converted to SQL <IS NULL>
2207 $stmt = "WHERE user = ? AND status IS NULL";
2210 To test if a column IS NOT NULL:
2214 status => { '!=', undef },
2217 =head2 Specific comparison operators
2219 If you want to specify a different type of operator for your comparison,
2220 you can use a hashref for a given column:
2224 status => { '!=', 'completed' }
2227 Which would generate:
2229 $stmt = "WHERE user = ? AND status != ?";
2230 @bind = ('nwiger', 'completed');
2232 To test against multiple values, just enclose the values in an arrayref:
2234 status => { '=', ['assigned', 'in-progress', 'pending'] };
2236 Which would give you:
2238 "WHERE status = ? OR status = ? OR status = ?"
2241 The hashref can also contain multiple pairs, in which case it is expanded
2242 into an C<AND> of its elements:
2246 status => { '!=', 'completed', -not_like => 'pending%' }
2249 # Or more dynamically, like from a form
2250 $where{user} = 'nwiger';
2251 $where{status}{'!='} = 'completed';
2252 $where{status}{'-not_like'} = 'pending%';
2254 # Both generate this
2255 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2256 @bind = ('nwiger', 'completed', 'pending%');
2259 To get an OR instead, you can combine it with the arrayref idea:
2263 priority => [ { '=', 2 }, { '>', 5 } ]
2266 Which would generate:
2268 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2269 @bind = ('2', '5', 'nwiger');
2271 If you want to include literal SQL (with or without bind values), just use a
2272 scalar reference or reference to an arrayref as the value:
2275 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2276 date_expires => { '<' => \"now()" }
2279 Which would generate:
2281 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2282 @bind = ('11/26/2008');
2285 =head2 Logic and nesting operators
2287 In the example above,
2288 there is a subtle trap if you want to say something like
2289 this (notice the C<AND>):
2291 WHERE priority != ? AND priority != ?
2293 Because, in Perl you I<can't> do this:
2295 priority => { '!=' => 2, '!=' => 1 }
2297 As the second C<!=> key will obliterate the first. The solution
2298 is to use the special C<-modifier> form inside an arrayref:
2300 priority => [ -and => {'!=', 2},
2304 Normally, these would be joined by C<OR>, but the modifier tells it
2305 to use C<AND> instead. (Hint: You can use this in conjunction with the
2306 C<logic> option to C<new()> in order to change the way your queries
2307 work by default.) B<Important:> Note that the C<-modifier> goes
2308 B<INSIDE> the arrayref, as an extra first element. This will
2309 B<NOT> do what you think it might:
2311 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2313 Here is a quick list of equivalencies, since there is some overlap:
2316 status => {'!=', 'completed', 'not like', 'pending%' }
2317 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2320 status => {'=', ['assigned', 'in-progress']}
2321 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2322 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2326 =head2 Special operators: IN, BETWEEN, etc.
2328 You can also use the hashref format to compare a list of fields using the
2329 C<IN> comparison operator, by specifying the list as an arrayref:
2332 status => 'completed',
2333 reportid => { -in => [567, 2335, 2] }
2336 Which would generate:
2338 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2339 @bind = ('completed', '567', '2335', '2');
2341 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2344 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2345 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2346 'sqltrue' (by default: C<1=1>).
2348 In addition to the array you can supply a chunk of literal sql or
2349 literal sql with bind:
2352 customer => { -in => \[
2353 'SELECT cust_id FROM cust WHERE balance > ?',
2356 status => { -in => \'SELECT status_codes FROM states' },
2362 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2363 AND status IN ( SELECT status_codes FROM states )
2367 Finally, if the argument to C<-in> is not a reference, it will be
2368 treated as a single-element array.
2370 Another pair of operators is C<-between> and C<-not_between>,
2371 used with an arrayref of two values:
2375 completion_date => {
2376 -not_between => ['2002-10-01', '2003-02-06']
2382 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2384 Just like with C<-in> all plausible combinations of literal SQL
2388 start0 => { -between => [ 1, 2 ] },
2389 start1 => { -between => \["? AND ?", 1, 2] },
2390 start2 => { -between => \"lower(x) AND upper(y)" },
2391 start3 => { -between => [
2393 \["upper(?)", 'stuff' ],
2400 ( start0 BETWEEN ? AND ? )
2401 AND ( start1 BETWEEN ? AND ? )
2402 AND ( start2 BETWEEN lower(x) AND upper(y) )
2403 AND ( start3 BETWEEN lower(x) AND upper(?) )
2405 @bind = (1, 2, 1, 2, 'stuff');
2408 These are the two builtin "special operators"; but the
2409 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2411 =head2 Unary operators: bool
2413 If you wish to test against boolean columns or functions within your
2414 database you can use the C<-bool> and C<-not_bool> operators. For
2415 example to test the column C<is_user> being true and the column
2416 C<is_enabled> being false you would use:-
2420 -not_bool => 'is_enabled',
2425 WHERE is_user AND NOT is_enabled
2427 If a more complex combination is required, testing more conditions,
2428 then you should use the and/or operators:-
2433 -not_bool => { two=> { -rlike => 'bar' } },
2434 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2445 (NOT ( three = ? OR three > ? ))
2448 =head2 Nested conditions, -and/-or prefixes
2450 So far, we've seen how multiple conditions are joined with a top-level
2451 C<AND>. We can change this by putting the different conditions we want in
2452 hashes and then putting those hashes in an array. For example:
2457 status => { -like => ['pending%', 'dispatched'] },
2461 status => 'unassigned',
2465 This data structure would create the following:
2467 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2468 OR ( user = ? AND status = ? ) )";
2469 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2472 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2473 to change the logic inside:
2479 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2480 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2487 $stmt = "WHERE ( user = ?
2488 AND ( ( workhrs > ? AND geo = ? )
2489 OR ( workhrs < ? OR geo = ? ) ) )";
2490 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2492 =head3 Algebraic inconsistency, for historical reasons
2494 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2495 operator goes C<outside> of the nested structure; whereas when connecting
2496 several constraints on one column, the C<-and> operator goes
2497 C<inside> the arrayref. Here is an example combining both features:
2500 -and => [a => 1, b => 2],
2501 -or => [c => 3, d => 4],
2502 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2507 WHERE ( ( ( a = ? AND b = ? )
2508 OR ( c = ? OR d = ? )
2509 OR ( e LIKE ? AND e LIKE ? ) ) )
2511 This difference in syntax is unfortunate but must be preserved for
2512 historical reasons. So be careful: the two examples below would
2513 seem algebraically equivalent, but they are not
2516 { -like => 'foo%' },
2517 { -like => '%bar' },
2519 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2522 { col => { -like => 'foo%' } },
2523 { col => { -like => '%bar' } },
2525 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2528 =head2 Literal SQL and value type operators
2530 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2531 side" is a column name and the "right side" is a value (normally rendered as
2532 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2533 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2534 alter this behavior. There are several ways of doing so.
2538 This is a virtual operator that signals the string to its right side is an
2539 identifier (a column name) and not a value. For example to compare two
2540 columns you would write:
2543 priority => { '<', 2 },
2544 requestor => { -ident => 'submitter' },
2549 $stmt = "WHERE priority < ? AND requestor = submitter";
2552 If you are maintaining legacy code you may see a different construct as
2553 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2558 This is a virtual operator that signals that the construct to its right side
2559 is a value to be passed to DBI. This is for example necessary when you want
2560 to write a where clause against an array (for RDBMS that support such
2561 datatypes). For example:
2564 array => { -value => [1, 2, 3] }
2569 $stmt = 'WHERE array = ?';
2570 @bind = ([1, 2, 3]);
2572 Note that if you were to simply say:
2578 the result would probably not be what you wanted:
2580 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2585 Finally, sometimes only literal SQL will do. To include a random snippet
2586 of SQL verbatim, you specify it as a scalar reference. Consider this only
2587 as a last resort. Usually there is a better way. For example:
2590 priority => { '<', 2 },
2591 requestor => { -in => \'(SELECT name FROM hitmen)' },
2596 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2599 Note that in this example, you only get one bind parameter back, since
2600 the verbatim SQL is passed as part of the statement.
2604 Never use untrusted input as a literal SQL argument - this is a massive
2605 security risk (there is no way to check literal snippets for SQL
2606 injections and other nastyness). If you need to deal with untrusted input
2607 use literal SQL with placeholders as described next.
2609 =head3 Literal SQL with placeholders and bind values (subqueries)
2611 If the literal SQL to be inserted has placeholders and bind values,
2612 use a reference to an arrayref (yes this is a double reference --
2613 not so common, but perfectly legal Perl). For example, to find a date
2614 in Postgres you can use something like this:
2617 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2622 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2625 Note that you must pass the bind values in the same format as they are returned
2626 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2627 to C<columns>, you must provide the bind values in the
2628 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2629 scalar value; most commonly the column name, but you can use any scalar value
2630 (including references and blessed references), L<SQL::Abstract> will simply
2631 pass it through intact. So if C<bindtype> is set to C<columns> the above
2632 example will look like:
2635 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2638 Literal SQL is especially useful for nesting parenthesized clauses in the
2639 main SQL query. Here is a first example:
2641 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2645 bar => \["IN ($sub_stmt)" => @sub_bind],
2650 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2651 WHERE c2 < ? AND c3 LIKE ?))";
2652 @bind = (1234, 100, "foo%");
2654 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2655 are expressed in the same way. Of course the C<$sub_stmt> and
2656 its associated bind values can be generated through a former call
2659 my ($sub_stmt, @sub_bind)
2660 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2661 c3 => {-like => "foo%"}});
2664 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2667 In the examples above, the subquery was used as an operator on a column;
2668 but the same principle also applies for a clause within the main C<%where>
2669 hash, like an EXISTS subquery:
2671 my ($sub_stmt, @sub_bind)
2672 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2673 my %where = ( -and => [
2675 \["EXISTS ($sub_stmt)" => @sub_bind],
2680 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2681 WHERE c1 = ? AND c2 > t0.c0))";
2685 Observe that the condition on C<c2> in the subquery refers to
2686 column C<t0.c0> of the main query: this is I<not> a bind
2687 value, so we have to express it through a scalar ref.
2688 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2689 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2690 what we wanted here.
2692 Finally, here is an example where a subquery is used
2693 for expressing unary negation:
2695 my ($sub_stmt, @sub_bind)
2696 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2697 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2699 lname => {like => '%son%'},
2700 \["NOT ($sub_stmt)" => @sub_bind],
2705 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2706 @bind = ('%son%', 10, 20)
2708 =head3 Deprecated usage of Literal SQL
2710 Below are some examples of archaic use of literal SQL. It is shown only as
2711 reference for those who deal with legacy code. Each example has a much
2712 better, cleaner and safer alternative that users should opt for in new code.
2718 my %where = ( requestor => \'IS NOT NULL' )
2720 $stmt = "WHERE requestor IS NOT NULL"
2722 This used to be the way of generating NULL comparisons, before the handling
2723 of C<undef> got formalized. For new code please use the superior syntax as
2724 described in L</Tests for NULL values>.
2728 my %where = ( requestor => \'= submitter' )
2730 $stmt = "WHERE requestor = submitter"
2732 This used to be the only way to compare columns. Use the superior L</-ident>
2733 method for all new code. For example an identifier declared in such a way
2734 will be properly quoted if L</quote_char> is properly set, while the legacy
2735 form will remain as supplied.
2739 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2741 $stmt = "WHERE completed > ? AND is_ready"
2742 @bind = ('2012-12-21')
2744 Using an empty string literal used to be the only way to express a boolean.
2745 For all new code please use the much more readable
2746 L<-bool|/Unary operators: bool> operator.
2752 These pages could go on for a while, since the nesting of the data
2753 structures this module can handle are pretty much unlimited (the
2754 module implements the C<WHERE> expansion as a recursive function
2755 internally). Your best bet is to "play around" with the module a
2756 little to see how the data structures behave, and choose the best
2757 format for your data based on that.
2759 And of course, all the values above will probably be replaced with
2760 variables gotten from forms or the command line. After all, if you
2761 knew everything ahead of time, you wouldn't have to worry about
2762 dynamically-generating SQL and could just hardwire it into your
2765 =head1 ORDER BY CLAUSES
2767 Some functions take an order by clause. This can either be a scalar (just a
2768 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2769 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2772 Given | Will Generate
2773 ---------------------------------------------------------------
2775 'colA' | ORDER BY colA
2777 [qw/colA colB/] | ORDER BY colA, colB
2779 {-asc => 'colA'} | ORDER BY colA ASC
2781 {-desc => 'colB'} | ORDER BY colB DESC
2783 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2785 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2787 \'colA DESC' | ORDER BY colA DESC
2789 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2790 | /* ...with $x bound to ? */
2793 { -asc => 'colA' }, | colA ASC,
2794 { -desc => [qw/colB/] }, | colB DESC,
2795 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2796 \'colE DESC', | colE DESC,
2797 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2798 ] | /* ...with $x bound to ? */
2799 ===============================================================
2803 =head1 SPECIAL OPERATORS
2805 my $sqlmaker = SQL::Abstract->new(special_ops => [
2809 my ($self, $field, $op, $arg) = @_;
2815 handler => 'method_name',
2819 A "special operator" is a SQL syntactic clause that can be
2820 applied to a field, instead of a usual binary operator.
2823 WHERE field IN (?, ?, ?)
2824 WHERE field BETWEEN ? AND ?
2825 WHERE MATCH(field) AGAINST (?, ?)
2827 Special operators IN and BETWEEN are fairly standard and therefore
2828 are builtin within C<SQL::Abstract> (as the overridable methods
2829 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2830 like the MATCH .. AGAINST example above which is specific to MySQL,
2831 you can write your own operator handlers - supply a C<special_ops>
2832 argument to the C<new> method. That argument takes an arrayref of
2833 operator definitions; each operator definition is a hashref with two
2840 the regular expression to match the operator
2844 Either a coderef or a plain scalar method name. In both cases
2845 the expected return is C<< ($sql, @bind) >>.
2847 When supplied with a method name, it is simply called on the
2848 L<SQL::Abstract> object as:
2850 $self->$method_name($field, $op, $arg)
2854 $field is the LHS of the operator
2855 $op is the part that matched the handler regex
2858 When supplied with a coderef, it is called as:
2860 $coderef->($self, $field, $op, $arg)
2865 For example, here is an implementation
2866 of the MATCH .. AGAINST syntax for MySQL
2868 my $sqlmaker = SQL::Abstract->new(special_ops => [
2870 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2871 {regex => qr/^match$/i,
2873 my ($self, $field, $op, $arg) = @_;
2874 $arg = [$arg] if not ref $arg;
2875 my $label = $self->_quote($field);
2876 my ($placeholder) = $self->_convert('?');
2877 my $placeholders = join ", ", (($placeholder) x @$arg);
2878 my $sql = $self->_sqlcase('match') . " ($label) "
2879 . $self->_sqlcase('against') . " ($placeholders) ";
2880 my @bind = $self->_bindtype($field, @$arg);
2881 return ($sql, @bind);
2888 =head1 UNARY OPERATORS
2890 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2894 my ($self, $op, $arg) = @_;
2900 handler => 'method_name',
2904 A "unary operator" is a SQL syntactic clause that can be
2905 applied to a field - the operator goes before the field
2907 You can write your own operator handlers - supply a C<unary_ops>
2908 argument to the C<new> method. That argument takes an arrayref of
2909 operator definitions; each operator definition is a hashref with two
2916 the regular expression to match the operator
2920 Either a coderef or a plain scalar method name. In both cases
2921 the expected return is C<< $sql >>.
2923 When supplied with a method name, it is simply called on the
2924 L<SQL::Abstract> object as:
2926 $self->$method_name($op, $arg)
2930 $op is the part that matched the handler regex
2931 $arg is the RHS or argument of the operator
2933 When supplied with a coderef, it is called as:
2935 $coderef->($self, $op, $arg)
2943 Thanks to some benchmarking by Mark Stosberg, it turns out that
2944 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2945 I must admit this wasn't an intentional design issue, but it's a
2946 byproduct of the fact that you get to control your C<DBI> handles
2949 To maximize performance, use a code snippet like the following:
2951 # prepare a statement handle using the first row
2952 # and then reuse it for the rest of the rows
2954 for my $href (@array_of_hashrefs) {
2955 $stmt ||= $sql->insert('table', $href);
2956 $sth ||= $dbh->prepare($stmt);
2957 $sth->execute($sql->values($href));
2960 The reason this works is because the keys in your C<$href> are sorted
2961 internally by B<SQL::Abstract>. Thus, as long as your data retains
2962 the same structure, you only have to generate the SQL the first time
2963 around. On subsequent queries, simply use the C<values> function provided
2964 by this module to return your values in the correct order.
2966 However this depends on the values having the same type - if, for
2967 example, the values of a where clause may either have values
2968 (resulting in sql of the form C<column = ?> with a single bind
2969 value), or alternatively the values might be C<undef> (resulting in
2970 sql of the form C<column IS NULL> with no bind value) then the
2971 caching technique suggested will not work.
2975 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2976 really like this part (I do, at least). Building up a complex query
2977 can be as simple as the following:
2984 use CGI::FormBuilder;
2987 my $form = CGI::FormBuilder->new(...);
2988 my $sql = SQL::Abstract->new;
2990 if ($form->submitted) {
2991 my $field = $form->field;
2992 my $id = delete $field->{id};
2993 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2996 Of course, you would still have to connect using C<DBI> to run the
2997 query, but the point is that if you make your form look like your
2998 table, the actual query script can be extremely simplistic.
3000 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3001 a fast interface to returning and formatting data. I frequently
3002 use these three modules together to write complex database query
3003 apps in under 50 lines.
3005 =head1 HOW TO CONTRIBUTE
3007 Contributions are always welcome, in all usable forms (we especially
3008 welcome documentation improvements). The delivery methods include git-
3009 or unified-diff formatted patches, GitHub pull requests, or plain bug
3010 reports either via RT or the Mailing list. Contributors are generally
3011 granted full access to the official repository after their first several
3012 patches pass successful review.
3014 This project is maintained in a git repository. The code and related tools are
3015 accessible at the following locations:
3019 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3021 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3023 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3025 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3031 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3032 Great care has been taken to preserve the I<published> behavior
3033 documented in previous versions in the 1.* family; however,
3034 some features that were previously undocumented, or behaved
3035 differently from the documentation, had to be changed in order
3036 to clarify the semantics. Hence, client code that was relying
3037 on some dark areas of C<SQL::Abstract> v1.*
3038 B<might behave differently> in v1.50.
3040 The main changes are:
3046 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3050 support for the { operator => \"..." } construct (to embed literal SQL)
3054 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3058 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3062 defensive programming: check arguments
3066 fixed bug with global logic, which was previously implemented
3067 through global variables yielding side-effects. Prior versions would
3068 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3069 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3070 Now this is interpreted
3071 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3076 fixed semantics of _bindtype on array args
3080 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3081 we just avoid shifting arrays within that tree.
3085 dropped the C<_modlogic> function
3089 =head1 ACKNOWLEDGEMENTS
3091 There are a number of individuals that have really helped out with
3092 this module. Unfortunately, most of them submitted bugs via CPAN
3093 so I have no idea who they are! But the people I do know are:
3095 Ash Berlin (order_by hash term support)
3096 Matt Trout (DBIx::Class support)
3097 Mark Stosberg (benchmarking)
3098 Chas Owens (initial "IN" operator support)
3099 Philip Collins (per-field SQL functions)
3100 Eric Kolve (hashref "AND" support)
3101 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3102 Dan Kubb (support for "quote_char" and "name_sep")
3103 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3104 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3105 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3106 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3107 Oliver Charles (support for "RETURNING" after "INSERT")
3113 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3117 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3119 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3121 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3122 While not an official support venue, C<DBIx::Class> makes heavy use of
3123 C<SQL::Abstract>, and as such list members there are very familiar with
3124 how to create queries.
3128 This module is free software; you may copy this under the same
3129 terms as perl itself (either the GNU General Public License or
3130 the Artistic License)