1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
164 $opt{unary_ops} ||= [];
166 # rudimentary sanity-check for user supplied bits treated as functions/operators
167 # If a purported function matches this regular expression, an exception is thrown.
168 # Literal SQL is *NOT* subject to this check, only functions (and column names
169 # when quoting is not in effect)
172 # need to guard against ()'s in column names too, but this will break tons of
173 # hacks... ideas anyone?
174 $opt{injection_guard} ||= qr/
180 $opt{node_types} = +{
181 map +("-$_" => '_render_'.$_),
182 qw(op func value bind ident literal)
185 $opt{expand_unary} = {};
187 return bless \%opt, $class;
190 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
191 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
193 sub _assert_pass_injection_guard {
194 if ($_[1] =~ $_[0]->{injection_guard}) {
195 my $class = ref $_[0];
196 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
197 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
198 . "{injection_guard} attribute to ${class}->new()"
203 #======================================================================
205 #======================================================================
209 my $table = $self->_table(shift);
210 my $data = shift || return;
213 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
214 my ($sql, @bind) = $self->$method($data);
215 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
217 if ($options->{returning}) {
218 my ($s, @b) = $self->_insert_returning($options);
223 return wantarray ? ($sql, @bind) : $sql;
226 # So that subclasses can override INSERT ... RETURNING separately from
227 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
228 sub _insert_returning { shift->_returning(@_) }
231 my ($self, $options) = @_;
233 my $f = $options->{returning};
235 my ($sql, @bind) = $self->_render_expr(
236 $self->_expand_maybe_list_expr($f, undef, -ident)
239 ? $self->_sqlcase(' returning ') . $sql
240 : ($self->_sqlcase(' returning ').$sql, @bind);
243 sub _insert_HASHREF { # explicit list of fields and then values
244 my ($self, $data) = @_;
246 my @fields = sort keys %$data;
248 my ($sql, @bind) = $self->_insert_values($data);
251 $_ = $self->_quote($_) foreach @fields;
252 $sql = "( ".join(", ", @fields).") ".$sql;
254 return ($sql, @bind);
257 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
258 my ($self, $data) = @_;
260 # no names (arrayref) so can't generate bindtype
261 $self->{bindtype} ne 'columns'
262 or belch "can't do 'columns' bindtype when called with arrayref";
264 my (@values, @all_bind);
265 foreach my $value (@$data) {
266 my ($values, @bind) = $self->_insert_value(undef, $value);
267 push @values, $values;
268 push @all_bind, @bind;
270 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
271 return ($sql, @all_bind);
274 sub _insert_ARRAYREFREF { # literal SQL with bind
275 my ($self, $data) = @_;
277 my ($sql, @bind) = @${$data};
278 $self->_assert_bindval_matches_bindtype(@bind);
280 return ($sql, @bind);
284 sub _insert_SCALARREF { # literal SQL without bind
285 my ($self, $data) = @_;
291 my ($self, $data) = @_;
293 my (@values, @all_bind);
294 foreach my $column (sort keys %$data) {
295 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
296 push @values, $values;
297 push @all_bind, @bind;
299 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
300 return ($sql, @all_bind);
304 my ($self, $column, $v) = @_;
306 return $self->_render_expr(
307 $self->_expand_insert_value($column, $v)
311 sub _expand_insert_value {
312 my ($self, $column, $v) = @_;
314 if (ref($v) eq 'ARRAY') {
315 if ($self->{array_datatypes}) {
316 return +{ -bind => [ $column, $v ] };
318 my ($sql, @bind) = @$v;
319 $self->_assert_bindval_matches_bindtype(@bind);
320 return +{ -literal => $v };
322 if (ref($v) eq 'HASH') {
323 if (grep !/^-/, keys %$v) {
324 belch "HASH ref as bind value in insert is not supported";
325 return +{ -bind => [ $column, $v ] };
329 return +{ -bind => [ $column, undef ] };
331 local our $Cur_Col_Meta = $column;
332 return $self->_expand_expr($v);
337 #======================================================================
339 #======================================================================
344 my $table = $self->_table(shift);
345 my $data = shift || return;
349 # first build the 'SET' part of the sql statement
350 puke "Unsupported data type specified to \$sql->update"
351 unless ref $data eq 'HASH';
353 my ($sql, @all_bind) = $self->_update_set_values($data);
354 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
358 my($where_sql, @where_bind) = $self->where($where);
360 push @all_bind, @where_bind;
363 if ($options->{returning}) {
364 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
365 $sql .= $returning_sql;
366 push @all_bind, @returning_bind;
369 return wantarray ? ($sql, @all_bind) : $sql;
372 sub _update_set_values {
373 my ($self, $data) = @_;
375 return $self->_render_expr(
376 $self->_expand_update_set_values($data),
380 sub _expand_update_set_values {
381 my ($self, $data) = @_;
382 $self->_expand_maybe_list_expr( [
385 $set = { -bind => $_ } unless defined $set;
386 +{ -op => [ '=', { -ident => $k }, $set ] };
392 ? ($self->{array_datatypes}
393 ? [ $k, +{ -bind => [ $k, $v ] } ]
394 : [ $k, +{ -literal => $v } ])
396 local our $Cur_Col_Meta = $k;
397 [ $k, $self->_expand_expr($v) ]
404 # So that subclasses can override UPDATE ... RETURNING separately from
406 sub _update_returning { shift->_returning(@_) }
410 #======================================================================
412 #======================================================================
417 my $table = $self->_table(shift);
418 my $fields = shift || '*';
422 my ($fields_sql, @bind) = $self->_select_fields($fields);
424 my ($where_sql, @where_bind) = $self->where($where, $order);
425 push @bind, @where_bind;
427 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
428 $self->_sqlcase('from'), $table)
431 return wantarray ? ($sql, @bind) : $sql;
435 my ($self, $fields) = @_;
436 return $fields unless ref($fields);
437 return $self->_render_expr(
438 $self->_expand_maybe_list_expr($fields, undef, '-ident')
442 #======================================================================
444 #======================================================================
449 my $table = $self->_table(shift);
453 my($where_sql, @bind) = $self->where($where);
454 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
456 if ($options->{returning}) {
457 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
458 $sql .= $returning_sql;
459 push @bind, @returning_bind;
462 return wantarray ? ($sql, @bind) : $sql;
465 # So that subclasses can override DELETE ... RETURNING separately from
467 sub _delete_returning { shift->_returning(@_) }
471 #======================================================================
473 #======================================================================
477 # Finally, a separate routine just to handle WHERE clauses
479 my ($self, $where, $order) = @_;
481 local $self->{convert_where} = $self->{convert};
484 my ($sql, @bind) = defined($where)
485 ? $self->_recurse_where($where)
487 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
491 my ($order_sql, @order_bind) = $self->_order_by($order);
493 push @bind, @order_bind;
496 return wantarray ? ($sql, @bind) : $sql;
500 my ($self, $expr, $logic, $default_scalar_to) = @_;
501 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
502 return undef unless defined($expr);
503 if (ref($expr) eq 'HASH') {
504 if (keys %$expr > 1) {
508 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
512 return unless %$expr;
513 return $self->_expand_expr_hashpair(%$expr, $logic);
515 if (ref($expr) eq 'ARRAY') {
516 my $logic = lc($logic || $self->{logic});
517 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
523 while (my ($el) = splice @expr, 0, 1) {
524 puke "Supplying an empty left hand side argument is not supported in array-pairs"
525 unless defined($el) and length($el);
526 my $elref = ref($el);
528 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
529 } elsif ($elref eq 'ARRAY') {
530 push(@res, $self->_expand_expr($el)) if @$el;
531 } elsif (my $l = is_literal_value($el)) {
532 push @res, { -literal => $l };
533 } elsif ($elref eq 'HASH') {
534 push @res, $self->_expand_expr($el);
539 return { -op => [ $logic, @res ] };
541 if (my $literal = is_literal_value($expr)) {
542 return +{ -literal => $literal };
544 if (!ref($expr) or Scalar::Util::blessed($expr)) {
545 if (my $d = $Default_Scalar_To) {
546 return +{ $d => $expr };
548 if (my $m = our $Cur_Col_Meta) {
549 return +{ -bind => [ $m, $expr ] };
551 return +{ -value => $expr };
556 sub _expand_expr_hashpair {
557 my ($self, $k, $v, $logic) = @_;
558 unless (defined($k) and length($k)) {
559 if (defined($k) and my $literal = is_literal_value($v)) {
560 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
561 return { -literal => $literal };
563 puke "Supplying an empty left hand side argument is not supported";
566 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
567 if ($k =~ s/ [_\s]? \d+ $//x ) {
568 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
569 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
572 return $self->_expand_expr($v);
576 return $self->_expand_expr($v);
578 puke "-bool => undef not supported" unless defined($v);
579 return { -ident => $v };
582 return { -op => [ 'not', $self->_expand_expr($v) ] };
584 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
587 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
590 if (my ($logic) = $k =~ /^-(and|or)$/i) {
591 if (ref($v) eq 'HASH') {
592 return $self->_expand_expr($v, $logic);
594 if (ref($v) eq 'ARRAY') {
595 return $self->_expand_expr($v, $logic);
600 $op =~ s/^-// if length($op) > 1;
602 # top level special ops are illegal in general
603 puke "Illegal use of top-level '-$op'"
604 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
605 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
606 return { -op => [ $op, $v ] };
609 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
610 return +{ -bind => [ $m, $v ] };
612 if (my $custom = $self->{expand_unary}{$k}) {
613 return $self->$custom($v);
615 if ($self->{node_types}{$k}) {
621 and (keys %$v)[0] =~ /^-/
623 my ($func) = $k =~ /^-(.*)$/;
624 return +{ -func => [ $func, $self->_expand_expr($v) ] };
626 if (!ref($v) or is_literal_value($v)) {
627 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
634 and exists $v->{-value}
635 and not defined $v->{-value}
638 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
640 if (!ref($v) or Scalar::Util::blessed($v)) {
641 my $d = our $Default_Scalar_To;
646 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
650 if (ref($v) eq 'HASH') {
654 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
661 $self->_assert_pass_injection_guard($vk);
662 if ($vk =~ s/ [_\s]? \d+ $//x ) {
663 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
664 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
666 if ($vk =~ /^(?:not[ _])?between$/) {
667 local our $Cur_Col_Meta = $k;
668 my @rhs = map $self->_expand_expr($_),
669 ref($vv) eq 'ARRAY' ? @$vv : $vv;
671 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
673 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
675 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
678 join(' ', split '_', $vk),
683 if ($vk =~ /^(?:not[ _])?in$/) {
684 if (my $literal = is_literal_value($vv)) {
685 my ($sql, @bind) = @$literal;
686 my $opened_sql = $self->_open_outer_paren($sql);
688 $vk, { -ident => $k },
689 [ { -literal => [ $opened_sql, @bind ] } ]
693 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
694 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
695 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
696 . 'will emit the logically correct SQL instead of raising this exception)'
698 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
700 my @rhs = map $self->_expand_expr($_),
701 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
702 map { defined($_) ? $_: puke($undef_err) }
703 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
704 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
707 join(' ', split '_', $vk),
712 if ($vk eq 'ident') {
713 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
714 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
722 if ($vk eq 'value') {
723 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
727 { -bind => [ $k, $vv ] }
730 if ($vk =~ /^is(?:[ _]not)?$/) {
731 puke "$vk can only take undef as argument"
735 and exists($vv->{-value})
736 and !defined($vv->{-value})
739 return +{ -op => [ $vk.' null', { -ident => $k } ] };
741 if ($vk =~ /^(and|or)$/) {
742 if (ref($vv) eq 'HASH') {
745 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
750 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
751 return { -op => [ $vk, { -ident => $k }, $vv ] };
753 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
757 { -op => [ $vk, $vv ] }
760 if (ref($vv) eq 'ARRAY') {
761 my ($logic, @values) = (
762 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
767 $vk =~ $self->{inequality_op}
768 or join(' ', split '_', $vk) =~ $self->{not_like_op}
770 if (lc($logic) eq '-or' and @values > 1) {
771 my $op = uc join ' ', split '_', $vk;
772 belch "A multi-element arrayref as an argument to the inequality op '$op' "
773 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
774 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
779 # try to DWIM on equality operators
780 my $op = join ' ', split '_', $vk;
782 $op =~ $self->{equality_op} ? $self->sqlfalse
783 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
784 : $op =~ $self->{inequality_op} ? $self->sqltrue
785 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
786 : puke "operator '$op' applied on an empty array (field '$k')";
790 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
798 and exists $vv->{-value}
799 and not defined $vv->{-value}
802 my $op = join ' ', split '_', $vk;
804 $op =~ /^not$/i ? 'is not' # legacy
805 : $op =~ $self->{equality_op} ? 'is'
806 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
807 : $op =~ $self->{inequality_op} ? 'is not'
808 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
809 : puke "unexpected operator '$op' with undef operand";
810 return +{ -op => [ $is.' null', { -ident => $k } ] };
812 local our $Cur_Col_Meta = $k;
816 $self->_expand_expr($vv)
819 if (ref($v) eq 'ARRAY') {
820 return $self->sqlfalse unless @$v;
821 $self->_debug("ARRAY($k) means distribute over elements");
823 $v->[0] =~ /^-((?:and|or))$/i
824 ? ($v = [ @{$v}[1..$#$v] ], $1)
825 : ($self->{logic} || 'or')
829 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
832 if (my $literal = is_literal_value($v)) {
834 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
837 my ($sql, @bind) = @$literal;
838 if ($self->{bindtype} eq 'columns') {
840 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
841 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
845 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
851 my ($self, $expr) = @_;
852 my ($k, $v, @rest) = %$expr;
854 if (my $meth = $self->{node_types}{$k}) {
855 return $self->$meth($v);
857 die "notreached: $k";
861 my ($self, $where, $logic) = @_;
863 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
865 # Special case: top level simple string treated as literal
867 my $where_exp = (ref($where)
868 ? $self->_expand_expr($where, $logic)
869 : { -literal => [ $where ] });
871 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
873 # dispatch on appropriate method according to refkind of $where
874 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
876 # my ($sql, @bind) = $self->$method($where_exp, $logic);
878 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
880 # DBIx::Class used to call _recurse_where in scalar context
881 # something else might too...
883 return ($sql, @bind);
886 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
892 my ($self, $ident) = @_;
894 return $self->_convert($self->_quote($ident));
898 my ($self, $value) = @_;
900 return ($self->_convert('?'), $self->_bindtype(undef, $value));
903 my %unop_postfix = map +($_ => 1),
904 'is null', 'is not null',
912 my ($self, $args) = @_;
913 my ($left, $low, $high) = @$args;
914 my ($rhsql, @rhbind) = do {
916 puke "Single arg to between must be a literal"
917 unless $low->{-literal};
920 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
921 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
922 @{$l}[1..$#$l], @{$h}[1..$#$h])
925 my ($lhsql, @lhbind) = $self->_render_expr($left);
927 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
931 }), 'between', 'not between'),
935 my ($self, $args) = @_;
936 my ($lhs, $rhs) = @$args;
939 my ($sql, @bind) = $self->_render_expr($_);
940 push @in_bind, @bind;
943 my ($lhsql, @lbind) = $self->_render_expr($lhs);
945 $lhsql.' '.$self->_sqlcase($op).' ( '
956 my ($op, @args) = @$v;
957 $op =~ s/^-// if length($op) > 1;
959 if (my $h = $special{$op}) {
960 return $self->$h(\@args);
962 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
963 puke "Special op '${op}' requires first value to be identifier"
964 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
965 return $self->${\($us->{handler})}($k, $op, $args[1]);
967 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
968 return $self->${\($us->{handler})}($op, $args[0]);
970 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
971 if (@args == 1 and $op !~ /^(and|or)$/) {
972 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
973 my $op_sql = $self->_sqlcase($final_op);
975 $unop_postfix{lc($final_op)}
976 ? "${expr_sql} ${op_sql}"
977 : "${op_sql} ${expr_sql}"
979 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
981 my @parts = map [ $self->_render_expr($_) ], @args;
982 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
983 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
988 map @{$_}[1..$#$_], @parts
995 my ($self, $rest) = @_;
996 my ($func, @args) = @$rest;
1000 push @arg_sql, shift @x;
1002 } map [ $self->_render_expr($_) ], @args;
1003 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1007 my ($self, $bind) = @_;
1008 return ($self->_convert('?'), $self->_bindtype(@$bind));
1011 sub _render_literal {
1012 my ($self, $literal) = @_;
1013 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1017 # Some databases (SQLite) treat col IN (1, 2) different from
1018 # col IN ( (1, 2) ). Use this to strip all outer parens while
1019 # adding them back in the corresponding method
1020 sub _open_outer_paren {
1021 my ($self, $sql) = @_;
1023 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1025 # there are closing parens inside, need the heavy duty machinery
1026 # to reevaluate the extraction starting from $sql (full reevaluation)
1027 if ($inner =~ /\)/) {
1028 require Text::Balanced;
1030 my (undef, $remainder) = do {
1031 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1033 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1036 # the entire expression needs to be a balanced bracketed thing
1037 # (after an extract no remainder sans trailing space)
1038 last if defined $remainder and $remainder =~ /\S/;
1048 #======================================================================
1050 #======================================================================
1052 sub _expand_order_by {
1053 my ($self, $arg) = @_;
1055 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1057 my $expander = sub {
1058 my ($self, $dir, $expr) = @_;
1059 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1060 foreach my $arg (@to_expand) {
1064 and grep /^-(asc|desc)$/, keys %$arg
1066 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1069 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1070 map $self->_expand_expr($_, undef, -ident), @to_expand;
1071 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1074 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1075 sub { shift->$expander(asc => @_) },
1076 sub { shift->$expander(desc => @_) },
1079 return $self->$expander(undef, $arg);
1083 my ($self, $arg) = @_;
1085 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1087 my ($sql, @bind) = $self->_render_expr($expanded);
1089 my $final_sql = $self->_sqlcase(' order by ').$sql;
1091 return wantarray ? ($final_sql, @bind) : $final_sql;
1094 sub _order_by_chunks {
1095 my ($self, $arg) = @_;
1097 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1100 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1101 if ($op->[0] eq ',') {
1102 return map [ $self->_render_expr($_) ], @{$op}[1..$#$op];
1105 return [ $self->_render_expr($_) ];
1109 #======================================================================
1110 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1111 #======================================================================
1116 ($self->_render_expr(
1117 $self->_expand_maybe_list_expr($from, undef, -ident)
1122 #======================================================================
1124 #======================================================================
1126 sub _expand_maybe_list_expr {
1127 my ($self, $expr, $logic, $default) = @_;
1129 if (ref($expr) eq 'ARRAY') {
1131 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1138 return $self->_expand_expr($e, $logic, $default);
1141 # highly optimized, as it's called way too often
1143 # my ($self, $label) = @_;
1145 return '' unless defined $_[1];
1146 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1147 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1149 unless ($_[0]->{quote_char}) {
1150 if (ref($_[1]) eq 'ARRAY') {
1151 return join($_[0]->{name_sep}||'.', @{$_[1]});
1153 $_[0]->_assert_pass_injection_guard($_[1]);
1158 my $qref = ref $_[0]->{quote_char};
1160 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1161 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1162 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1164 my $esc = $_[0]->{escape_char} || $r;
1166 # parts containing * are naturally unquoted
1168 $_[0]->{name_sep}||'',
1172 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1174 (ref($_[1]) eq 'ARRAY'
1178 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1186 # Conversion, if applicable
1188 #my ($self, $arg) = @_;
1189 if ($_[0]->{convert_where}) {
1190 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1197 #my ($self, $col, @vals) = @_;
1198 # called often - tighten code
1199 return $_[0]->{bindtype} eq 'columns'
1200 ? map {[$_[1], $_]} @_[2 .. $#_]
1205 # Dies if any element of @bind is not in [colname => value] format
1206 # if bindtype is 'columns'.
1207 sub _assert_bindval_matches_bindtype {
1208 # my ($self, @bind) = @_;
1210 if ($self->{bindtype} eq 'columns') {
1212 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1213 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1219 sub _join_sql_clauses {
1220 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1222 if (@$clauses_aref > 1) {
1223 my $join = " " . $self->_sqlcase($logic) . " ";
1224 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1225 return ($sql, @$bind_aref);
1227 elsif (@$clauses_aref) {
1228 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1231 return (); # if no SQL, ignore @$bind_aref
1236 # Fix SQL case, if so requested
1238 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1239 # don't touch the argument ... crooked logic, but let's not change it!
1240 return $_[0]->{case} ? $_[1] : uc($_[1]);
1244 #======================================================================
1245 # DISPATCHING FROM REFKIND
1246 #======================================================================
1249 my ($self, $data) = @_;
1251 return 'UNDEF' unless defined $data;
1253 # blessed objects are treated like scalars
1254 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1256 return 'SCALAR' unless $ref;
1259 while ($ref eq 'REF') {
1261 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1265 return ($ref||'SCALAR') . ('REF' x $n_steps);
1269 my ($self, $data) = @_;
1270 my @try = ($self->_refkind($data));
1271 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1272 push @try, 'FALLBACK';
1276 sub _METHOD_FOR_refkind {
1277 my ($self, $meth_prefix, $data) = @_;
1280 for (@{$self->_try_refkind($data)}) {
1281 $method = $self->can($meth_prefix."_".$_)
1285 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1289 sub _SWITCH_refkind {
1290 my ($self, $data, $dispatch_table) = @_;
1293 for (@{$self->_try_refkind($data)}) {
1294 $coderef = $dispatch_table->{$_}
1298 puke "no dispatch entry for ".$self->_refkind($data)
1307 #======================================================================
1308 # VALUES, GENERATE, AUTOLOAD
1309 #======================================================================
1311 # LDNOTE: original code from nwiger, didn't touch code in that section
1312 # I feel the AUTOLOAD stuff should not be the default, it should
1313 # only be activated on explicit demand by user.
1317 my $data = shift || return;
1318 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1319 unless ref $data eq 'HASH';
1322 foreach my $k (sort keys %$data) {
1323 my $v = $data->{$k};
1324 $self->_SWITCH_refkind($v, {
1326 if ($self->{array_datatypes}) { # array datatype
1327 push @all_bind, $self->_bindtype($k, $v);
1329 else { # literal SQL with bind
1330 my ($sql, @bind) = @$v;
1331 $self->_assert_bindval_matches_bindtype(@bind);
1332 push @all_bind, @bind;
1335 ARRAYREFREF => sub { # literal SQL with bind
1336 my ($sql, @bind) = @${$v};
1337 $self->_assert_bindval_matches_bindtype(@bind);
1338 push @all_bind, @bind;
1340 SCALARREF => sub { # literal SQL without bind
1342 SCALAR_or_UNDEF => sub {
1343 push @all_bind, $self->_bindtype($k, $v);
1354 my(@sql, @sqlq, @sqlv);
1358 if ($ref eq 'HASH') {
1359 for my $k (sort keys %$_) {
1362 my $label = $self->_quote($k);
1363 if ($r eq 'ARRAY') {
1364 # literal SQL with bind
1365 my ($sql, @bind) = @$v;
1366 $self->_assert_bindval_matches_bindtype(@bind);
1367 push @sqlq, "$label = $sql";
1369 } elsif ($r eq 'SCALAR') {
1370 # literal SQL without bind
1371 push @sqlq, "$label = $$v";
1373 push @sqlq, "$label = ?";
1374 push @sqlv, $self->_bindtype($k, $v);
1377 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1378 } elsif ($ref eq 'ARRAY') {
1379 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1382 if ($r eq 'ARRAY') { # literal SQL with bind
1383 my ($sql, @bind) = @$v;
1384 $self->_assert_bindval_matches_bindtype(@bind);
1387 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1388 # embedded literal SQL
1395 push @sql, '(' . join(', ', @sqlq) . ')';
1396 } elsif ($ref eq 'SCALAR') {
1400 # strings get case twiddled
1401 push @sql, $self->_sqlcase($_);
1405 my $sql = join ' ', @sql;
1407 # this is pretty tricky
1408 # if ask for an array, return ($stmt, @bind)
1409 # otherwise, s/?/shift @sqlv/ to put it inline
1411 return ($sql, @sqlv);
1413 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1414 ref $d ? $d->[1] : $d/e;
1423 # This allows us to check for a local, then _form, attr
1425 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1426 return $self->generate($name, @_);
1437 SQL::Abstract - Generate SQL from Perl data structures
1443 my $sql = SQL::Abstract->new;
1445 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1447 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1449 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1451 my($stmt, @bind) = $sql->delete($table, \%where);
1453 # Then, use these in your DBI statements
1454 my $sth = $dbh->prepare($stmt);
1455 $sth->execute(@bind);
1457 # Just generate the WHERE clause
1458 my($stmt, @bind) = $sql->where(\%where, $order);
1460 # Return values in the same order, for hashed queries
1461 # See PERFORMANCE section for more details
1462 my @bind = $sql->values(\%fieldvals);
1466 This module was inspired by the excellent L<DBIx::Abstract>.
1467 However, in using that module I found that what I really wanted
1468 to do was generate SQL, but still retain complete control over my
1469 statement handles and use the DBI interface. So, I set out to
1470 create an abstract SQL generation module.
1472 While based on the concepts used by L<DBIx::Abstract>, there are
1473 several important differences, especially when it comes to WHERE
1474 clauses. I have modified the concepts used to make the SQL easier
1475 to generate from Perl data structures and, IMO, more intuitive.
1476 The underlying idea is for this module to do what you mean, based
1477 on the data structures you provide it. The big advantage is that
1478 you don't have to modify your code every time your data changes,
1479 as this module figures it out.
1481 To begin with, an SQL INSERT is as easy as just specifying a hash
1482 of C<key=value> pairs:
1485 name => 'Jimbo Bobson',
1486 phone => '123-456-7890',
1487 address => '42 Sister Lane',
1488 city => 'St. Louis',
1489 state => 'Louisiana',
1492 The SQL can then be generated with this:
1494 my($stmt, @bind) = $sql->insert('people', \%data);
1496 Which would give you something like this:
1498 $stmt = "INSERT INTO people
1499 (address, city, name, phone, state)
1500 VALUES (?, ?, ?, ?, ?)";
1501 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1502 '123-456-7890', 'Louisiana');
1504 These are then used directly in your DBI code:
1506 my $sth = $dbh->prepare($stmt);
1507 $sth->execute(@bind);
1509 =head2 Inserting and Updating Arrays
1511 If your database has array types (like for example Postgres),
1512 activate the special option C<< array_datatypes => 1 >>
1513 when creating the C<SQL::Abstract> object.
1514 Then you may use an arrayref to insert and update database array types:
1516 my $sql = SQL::Abstract->new(array_datatypes => 1);
1518 planets => [qw/Mercury Venus Earth Mars/]
1521 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1525 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1527 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1530 =head2 Inserting and Updating SQL
1532 In order to apply SQL functions to elements of your C<%data> you may
1533 specify a reference to an arrayref for the given hash value. For example,
1534 if you need to execute the Oracle C<to_date> function on a value, you can
1535 say something like this:
1539 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1542 The first value in the array is the actual SQL. Any other values are
1543 optional and would be included in the bind values array. This gives
1546 my($stmt, @bind) = $sql->insert('people', \%data);
1548 $stmt = "INSERT INTO people (name, date_entered)
1549 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1550 @bind = ('Bill', '03/02/2003');
1552 An UPDATE is just as easy, all you change is the name of the function:
1554 my($stmt, @bind) = $sql->update('people', \%data);
1556 Notice that your C<%data> isn't touched; the module will generate
1557 the appropriately quirky SQL for you automatically. Usually you'll
1558 want to specify a WHERE clause for your UPDATE, though, which is
1559 where handling C<%where> hashes comes in handy...
1561 =head2 Complex where statements
1563 This module can generate pretty complicated WHERE statements
1564 easily. For example, simple C<key=value> pairs are taken to mean
1565 equality, and if you want to see if a field is within a set
1566 of values, you can use an arrayref. Let's say we wanted to
1567 SELECT some data based on this criteria:
1570 requestor => 'inna',
1571 worker => ['nwiger', 'rcwe', 'sfz'],
1572 status => { '!=', 'completed' }
1575 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1577 The above would give you something like this:
1579 $stmt = "SELECT * FROM tickets WHERE
1580 ( requestor = ? ) AND ( status != ? )
1581 AND ( worker = ? OR worker = ? OR worker = ? )";
1582 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1584 Which you could then use in DBI code like so:
1586 my $sth = $dbh->prepare($stmt);
1587 $sth->execute(@bind);
1593 The methods are simple. There's one for every major SQL operation,
1594 and a constructor you use first. The arguments are specified in a
1595 similar order for each method (table, then fields, then a where
1596 clause) to try and simplify things.
1598 =head2 new(option => 'value')
1600 The C<new()> function takes a list of options and values, and returns
1601 a new B<SQL::Abstract> object which can then be used to generate SQL
1602 through the methods below. The options accepted are:
1608 If set to 'lower', then SQL will be generated in all lowercase. By
1609 default SQL is generated in "textbook" case meaning something like:
1611 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1613 Any setting other than 'lower' is ignored.
1617 This determines what the default comparison operator is. By default
1618 it is C<=>, meaning that a hash like this:
1620 %where = (name => 'nwiger', email => 'nate@wiger.org');
1622 Will generate SQL like this:
1624 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1626 However, you may want loose comparisons by default, so if you set
1627 C<cmp> to C<like> you would get SQL such as:
1629 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1631 You can also override the comparison on an individual basis - see
1632 the huge section on L</"WHERE CLAUSES"> at the bottom.
1634 =item sqltrue, sqlfalse
1636 Expressions for inserting boolean values within SQL statements.
1637 By default these are C<1=1> and C<1=0>. They are used
1638 by the special operators C<-in> and C<-not_in> for generating
1639 correct SQL even when the argument is an empty array (see below).
1643 This determines the default logical operator for multiple WHERE
1644 statements in arrays or hashes. If absent, the default logic is "or"
1645 for arrays, and "and" for hashes. This means that a WHERE
1649 event_date => {'>=', '2/13/99'},
1650 event_date => {'<=', '4/24/03'},
1653 will generate SQL like this:
1655 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1657 This is probably not what you want given this query, though (look
1658 at the dates). To change the "OR" to an "AND", simply specify:
1660 my $sql = SQL::Abstract->new(logic => 'and');
1662 Which will change the above C<WHERE> to:
1664 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1666 The logic can also be changed locally by inserting
1667 a modifier in front of an arrayref:
1669 @where = (-and => [event_date => {'>=', '2/13/99'},
1670 event_date => {'<=', '4/24/03'} ]);
1672 See the L</"WHERE CLAUSES"> section for explanations.
1676 This will automatically convert comparisons using the specified SQL
1677 function for both column and value. This is mostly used with an argument
1678 of C<upper> or C<lower>, so that the SQL will have the effect of
1679 case-insensitive "searches". For example, this:
1681 $sql = SQL::Abstract->new(convert => 'upper');
1682 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1684 Will turn out the following SQL:
1686 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1688 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1689 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1690 not validate this option; it will just pass through what you specify verbatim).
1694 This is a kludge because many databases suck. For example, you can't
1695 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1696 Instead, you have to use C<bind_param()>:
1698 $sth->bind_param(1, 'reg data');
1699 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1701 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1702 which loses track of which field each slot refers to. Fear not.
1704 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1705 Currently, you can specify either C<normal> (default) or C<columns>. If you
1706 specify C<columns>, you will get an array that looks like this:
1708 my $sql = SQL::Abstract->new(bindtype => 'columns');
1709 my($stmt, @bind) = $sql->insert(...);
1712 [ 'column1', 'value1' ],
1713 [ 'column2', 'value2' ],
1714 [ 'column3', 'value3' ],
1717 You can then iterate through this manually, using DBI's C<bind_param()>.
1719 $sth->prepare($stmt);
1722 my($col, $data) = @$_;
1723 if ($col eq 'details' || $col eq 'comments') {
1724 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1725 } elsif ($col eq 'image') {
1726 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1728 $sth->bind_param($i, $data);
1732 $sth->execute; # execute without @bind now
1734 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1735 Basically, the advantage is still that you don't have to care which fields
1736 are or are not included. You could wrap that above C<for> loop in a simple
1737 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1738 get a layer of abstraction over manual SQL specification.
1740 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1741 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1742 will expect the bind values in this format.
1746 This is the character that a table or column name will be quoted
1747 with. By default this is an empty string, but you could set it to
1748 the character C<`>, to generate SQL like this:
1750 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1752 Alternatively, you can supply an array ref of two items, the first being the left
1753 hand quote character, and the second the right hand quote character. For
1754 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1755 that generates SQL like this:
1757 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1759 Quoting is useful if you have tables or columns names that are reserved
1760 words in your database's SQL dialect.
1764 This is the character that will be used to escape L</quote_char>s appearing
1765 in an identifier before it has been quoted.
1767 The parameter default in case of a single L</quote_char> character is the quote
1770 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1771 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1772 of the B<opening (left)> L</quote_char> within the identifier are currently left
1773 untouched. The default for opening-closing-style quotes may change in future
1774 versions, thus you are B<strongly encouraged> to specify the escape character
1779 This is the character that separates a table and column name. It is
1780 necessary to specify this when the C<quote_char> option is selected,
1781 so that tables and column names can be individually quoted like this:
1783 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1785 =item injection_guard
1787 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1788 column name specified in a query structure. This is a safety mechanism to avoid
1789 injection attacks when mishandling user input e.g.:
1791 my %condition_as_column_value_pairs = get_values_from_user();
1792 $sqla->select( ... , \%condition_as_column_value_pairs );
1794 If the expression matches an exception is thrown. Note that literal SQL
1795 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1797 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1799 =item array_datatypes
1801 When this option is true, arrayrefs in INSERT or UPDATE are
1802 interpreted as array datatypes and are passed directly
1804 When this option is false, arrayrefs are interpreted
1805 as literal SQL, just like refs to arrayrefs
1806 (but this behavior is for backwards compatibility; when writing
1807 new queries, use the "reference to arrayref" syntax
1813 Takes a reference to a list of "special operators"
1814 to extend the syntax understood by L<SQL::Abstract>.
1815 See section L</"SPECIAL OPERATORS"> for details.
1819 Takes a reference to a list of "unary operators"
1820 to extend the syntax understood by L<SQL::Abstract>.
1821 See section L</"UNARY OPERATORS"> for details.
1827 =head2 insert($table, \@values || \%fieldvals, \%options)
1829 This is the simplest function. You simply give it a table name
1830 and either an arrayref of values or hashref of field/value pairs.
1831 It returns an SQL INSERT statement and a list of bind values.
1832 See the sections on L</"Inserting and Updating Arrays"> and
1833 L</"Inserting and Updating SQL"> for information on how to insert
1834 with those data types.
1836 The optional C<\%options> hash reference may contain additional
1837 options to generate the insert SQL. Currently supported options
1844 Takes either a scalar of raw SQL fields, or an array reference of
1845 field names, and adds on an SQL C<RETURNING> statement at the end.
1846 This allows you to return data generated by the insert statement
1847 (such as row IDs) without performing another C<SELECT> statement.
1848 Note, however, this is not part of the SQL standard and may not
1849 be supported by all database engines.
1853 =head2 update($table, \%fieldvals, \%where, \%options)
1855 This takes a table, hashref of field/value pairs, and an optional
1856 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1858 See the sections on L</"Inserting and Updating Arrays"> and
1859 L</"Inserting and Updating SQL"> for information on how to insert
1860 with those data types.
1862 The optional C<\%options> hash reference may contain additional
1863 options to generate the update SQL. Currently supported options
1870 See the C<returning> option to
1871 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1875 =head2 select($source, $fields, $where, $order)
1877 This returns a SQL SELECT statement and associated list of bind values, as
1878 specified by the arguments:
1884 Specification of the 'FROM' part of the statement.
1885 The argument can be either a plain scalar (interpreted as a table
1886 name, will be quoted), or an arrayref (interpreted as a list
1887 of table names, joined by commas, quoted), or a scalarref
1888 (literal SQL, not quoted).
1892 Specification of the list of fields to retrieve from
1894 The argument can be either an arrayref (interpreted as a list
1895 of field names, will be joined by commas and quoted), or a
1896 plain scalar (literal SQL, not quoted).
1897 Please observe that this API is not as flexible as that of
1898 the first argument C<$source>, for backwards compatibility reasons.
1902 Optional argument to specify the WHERE part of the query.
1903 The argument is most often a hashref, but can also be
1904 an arrayref or plain scalar --
1905 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1909 Optional argument to specify the ORDER BY part of the query.
1910 The argument can be a scalar, a hashref or an arrayref
1911 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1917 =head2 delete($table, \%where, \%options)
1919 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1920 It returns an SQL DELETE statement and list of bind values.
1922 The optional C<\%options> hash reference may contain additional
1923 options to generate the delete SQL. Currently supported options
1930 See the C<returning> option to
1931 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1935 =head2 where(\%where, $order)
1937 This is used to generate just the WHERE clause. For example,
1938 if you have an arbitrary data structure and know what the
1939 rest of your SQL is going to look like, but want an easy way
1940 to produce a WHERE clause, use this. It returns an SQL WHERE
1941 clause and list of bind values.
1944 =head2 values(\%data)
1946 This just returns the values from the hash C<%data>, in the same
1947 order that would be returned from any of the other above queries.
1948 Using this allows you to markedly speed up your queries if you
1949 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1951 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1953 Warning: This is an experimental method and subject to change.
1955 This returns arbitrarily generated SQL. It's a really basic shortcut.
1956 It will return two different things, depending on return context:
1958 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1959 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1961 These would return the following:
1963 # First calling form
1964 $stmt = "CREATE TABLE test (?, ?)";
1965 @bind = (field1, field2);
1967 # Second calling form
1968 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1970 Depending on what you're trying to do, it's up to you to choose the correct
1971 format. In this example, the second form is what you would want.
1975 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1979 ALTER SESSION SET nls_date_format = 'MM/YY'
1981 You get the idea. Strings get their case twiddled, but everything
1982 else remains verbatim.
1984 =head1 EXPORTABLE FUNCTIONS
1986 =head2 is_plain_value
1988 Determines if the supplied argument is a plain value as understood by this
1993 =item * The value is C<undef>
1995 =item * The value is a non-reference
1997 =item * The value is an object with stringification overloading
1999 =item * The value is of the form C<< { -value => $anything } >>
2003 On failure returns C<undef>, on success returns a B<scalar> reference
2004 to the original supplied argument.
2010 The stringification overloading detection is rather advanced: it takes
2011 into consideration not only the presence of a C<""> overload, but if that
2012 fails also checks for enabled
2013 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2014 on either C<0+> or C<bool>.
2016 Unfortunately testing in the field indicates that this
2017 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2018 but only when very large numbers of stringifying objects are involved.
2019 At the time of writing ( Sep 2014 ) there is no clear explanation of
2020 the direct cause, nor is there a manageably small test case that reliably
2021 reproduces the problem.
2023 If you encounter any of the following exceptions in B<random places within
2024 your application stack> - this module may be to blame:
2026 Operation "ne": no method found,
2027 left argument in overloaded package <something>,
2028 right argument in overloaded package <something>
2032 Stub found while resolving method "???" overloading """" in package <something>
2034 If you fall victim to the above - please attempt to reduce the problem
2035 to something that could be sent to the L<SQL::Abstract developers
2036 |DBIx::Class/GETTING HELP/SUPPORT>
2037 (either publicly or privately). As a workaround in the meantime you can
2038 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2039 value, which will most likely eliminate your problem (at the expense of
2040 not being able to properly detect exotic forms of stringification).
2042 This notice and environment variable will be removed in a future version,
2043 as soon as the underlying problem is found and a reliable workaround is
2048 =head2 is_literal_value
2050 Determines if the supplied argument is a literal value as understood by this
2055 =item * C<\$sql_string>
2057 =item * C<\[ $sql_string, @bind_values ]>
2061 On failure returns C<undef>, on success returns an B<array> reference
2062 containing the unpacked version of the supplied literal SQL and bind values.
2064 =head1 WHERE CLAUSES
2068 This module uses a variation on the idea from L<DBIx::Abstract>. It
2069 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2070 module is that things in arrays are OR'ed, and things in hashes
2073 The easiest way to explain is to show lots of examples. After
2074 each C<%where> hash shown, it is assumed you used:
2076 my($stmt, @bind) = $sql->where(\%where);
2078 However, note that the C<%where> hash can be used directly in any
2079 of the other functions as well, as described above.
2081 =head2 Key-value pairs
2083 So, let's get started. To begin, a simple hash:
2087 status => 'completed'
2090 Is converted to SQL C<key = val> statements:
2092 $stmt = "WHERE user = ? AND status = ?";
2093 @bind = ('nwiger', 'completed');
2095 One common thing I end up doing is having a list of values that
2096 a field can be in. To do this, simply specify a list inside of
2101 status => ['assigned', 'in-progress', 'pending'];
2104 This simple code will create the following:
2106 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2107 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2109 A field associated to an empty arrayref will be considered a
2110 logical false and will generate 0=1.
2112 =head2 Tests for NULL values
2114 If the value part is C<undef> then this is converted to SQL <IS NULL>
2123 $stmt = "WHERE user = ? AND status IS NULL";
2126 To test if a column IS NOT NULL:
2130 status => { '!=', undef },
2133 =head2 Specific comparison operators
2135 If you want to specify a different type of operator for your comparison,
2136 you can use a hashref for a given column:
2140 status => { '!=', 'completed' }
2143 Which would generate:
2145 $stmt = "WHERE user = ? AND status != ?";
2146 @bind = ('nwiger', 'completed');
2148 To test against multiple values, just enclose the values in an arrayref:
2150 status => { '=', ['assigned', 'in-progress', 'pending'] };
2152 Which would give you:
2154 "WHERE status = ? OR status = ? OR status = ?"
2157 The hashref can also contain multiple pairs, in which case it is expanded
2158 into an C<AND> of its elements:
2162 status => { '!=', 'completed', -not_like => 'pending%' }
2165 # Or more dynamically, like from a form
2166 $where{user} = 'nwiger';
2167 $where{status}{'!='} = 'completed';
2168 $where{status}{'-not_like'} = 'pending%';
2170 # Both generate this
2171 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2172 @bind = ('nwiger', 'completed', 'pending%');
2175 To get an OR instead, you can combine it with the arrayref idea:
2179 priority => [ { '=', 2 }, { '>', 5 } ]
2182 Which would generate:
2184 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2185 @bind = ('2', '5', 'nwiger');
2187 If you want to include literal SQL (with or without bind values), just use a
2188 scalar reference or reference to an arrayref as the value:
2191 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2192 date_expires => { '<' => \"now()" }
2195 Which would generate:
2197 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2198 @bind = ('11/26/2008');
2201 =head2 Logic and nesting operators
2203 In the example above,
2204 there is a subtle trap if you want to say something like
2205 this (notice the C<AND>):
2207 WHERE priority != ? AND priority != ?
2209 Because, in Perl you I<can't> do this:
2211 priority => { '!=' => 2, '!=' => 1 }
2213 As the second C<!=> key will obliterate the first. The solution
2214 is to use the special C<-modifier> form inside an arrayref:
2216 priority => [ -and => {'!=', 2},
2220 Normally, these would be joined by C<OR>, but the modifier tells it
2221 to use C<AND> instead. (Hint: You can use this in conjunction with the
2222 C<logic> option to C<new()> in order to change the way your queries
2223 work by default.) B<Important:> Note that the C<-modifier> goes
2224 B<INSIDE> the arrayref, as an extra first element. This will
2225 B<NOT> do what you think it might:
2227 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2229 Here is a quick list of equivalencies, since there is some overlap:
2232 status => {'!=', 'completed', 'not like', 'pending%' }
2233 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2236 status => {'=', ['assigned', 'in-progress']}
2237 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2238 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2242 =head2 Special operators: IN, BETWEEN, etc.
2244 You can also use the hashref format to compare a list of fields using the
2245 C<IN> comparison operator, by specifying the list as an arrayref:
2248 status => 'completed',
2249 reportid => { -in => [567, 2335, 2] }
2252 Which would generate:
2254 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2255 @bind = ('completed', '567', '2335', '2');
2257 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2260 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2261 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2262 'sqltrue' (by default: C<1=1>).
2264 In addition to the array you can supply a chunk of literal sql or
2265 literal sql with bind:
2268 customer => { -in => \[
2269 'SELECT cust_id FROM cust WHERE balance > ?',
2272 status => { -in => \'SELECT status_codes FROM states' },
2278 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2279 AND status IN ( SELECT status_codes FROM states )
2283 Finally, if the argument to C<-in> is not a reference, it will be
2284 treated as a single-element array.
2286 Another pair of operators is C<-between> and C<-not_between>,
2287 used with an arrayref of two values:
2291 completion_date => {
2292 -not_between => ['2002-10-01', '2003-02-06']
2298 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2300 Just like with C<-in> all plausible combinations of literal SQL
2304 start0 => { -between => [ 1, 2 ] },
2305 start1 => { -between => \["? AND ?", 1, 2] },
2306 start2 => { -between => \"lower(x) AND upper(y)" },
2307 start3 => { -between => [
2309 \["upper(?)", 'stuff' ],
2316 ( start0 BETWEEN ? AND ? )
2317 AND ( start1 BETWEEN ? AND ? )
2318 AND ( start2 BETWEEN lower(x) AND upper(y) )
2319 AND ( start3 BETWEEN lower(x) AND upper(?) )
2321 @bind = (1, 2, 1, 2, 'stuff');
2324 These are the two builtin "special operators"; but the
2325 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2327 =head2 Unary operators: bool
2329 If you wish to test against boolean columns or functions within your
2330 database you can use the C<-bool> and C<-not_bool> operators. For
2331 example to test the column C<is_user> being true and the column
2332 C<is_enabled> being false you would use:-
2336 -not_bool => 'is_enabled',
2341 WHERE is_user AND NOT is_enabled
2343 If a more complex combination is required, testing more conditions,
2344 then you should use the and/or operators:-
2349 -not_bool => { two=> { -rlike => 'bar' } },
2350 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2361 (NOT ( three = ? OR three > ? ))
2364 =head2 Nested conditions, -and/-or prefixes
2366 So far, we've seen how multiple conditions are joined with a top-level
2367 C<AND>. We can change this by putting the different conditions we want in
2368 hashes and then putting those hashes in an array. For example:
2373 status => { -like => ['pending%', 'dispatched'] },
2377 status => 'unassigned',
2381 This data structure would create the following:
2383 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2384 OR ( user = ? AND status = ? ) )";
2385 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2388 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2389 to change the logic inside:
2395 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2396 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2403 $stmt = "WHERE ( user = ?
2404 AND ( ( workhrs > ? AND geo = ? )
2405 OR ( workhrs < ? OR geo = ? ) ) )";
2406 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2408 =head3 Algebraic inconsistency, for historical reasons
2410 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2411 operator goes C<outside> of the nested structure; whereas when connecting
2412 several constraints on one column, the C<-and> operator goes
2413 C<inside> the arrayref. Here is an example combining both features:
2416 -and => [a => 1, b => 2],
2417 -or => [c => 3, d => 4],
2418 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2423 WHERE ( ( ( a = ? AND b = ? )
2424 OR ( c = ? OR d = ? )
2425 OR ( e LIKE ? AND e LIKE ? ) ) )
2427 This difference in syntax is unfortunate but must be preserved for
2428 historical reasons. So be careful: the two examples below would
2429 seem algebraically equivalent, but they are not
2432 { -like => 'foo%' },
2433 { -like => '%bar' },
2435 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2438 { col => { -like => 'foo%' } },
2439 { col => { -like => '%bar' } },
2441 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2444 =head2 Literal SQL and value type operators
2446 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2447 side" is a column name and the "right side" is a value (normally rendered as
2448 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2449 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2450 alter this behavior. There are several ways of doing so.
2454 This is a virtual operator that signals the string to its right side is an
2455 identifier (a column name) and not a value. For example to compare two
2456 columns you would write:
2459 priority => { '<', 2 },
2460 requestor => { -ident => 'submitter' },
2465 $stmt = "WHERE priority < ? AND requestor = submitter";
2468 If you are maintaining legacy code you may see a different construct as
2469 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2474 This is a virtual operator that signals that the construct to its right side
2475 is a value to be passed to DBI. This is for example necessary when you want
2476 to write a where clause against an array (for RDBMS that support such
2477 datatypes). For example:
2480 array => { -value => [1, 2, 3] }
2485 $stmt = 'WHERE array = ?';
2486 @bind = ([1, 2, 3]);
2488 Note that if you were to simply say:
2494 the result would probably not be what you wanted:
2496 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2501 Finally, sometimes only literal SQL will do. To include a random snippet
2502 of SQL verbatim, you specify it as a scalar reference. Consider this only
2503 as a last resort. Usually there is a better way. For example:
2506 priority => { '<', 2 },
2507 requestor => { -in => \'(SELECT name FROM hitmen)' },
2512 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2515 Note that in this example, you only get one bind parameter back, since
2516 the verbatim SQL is passed as part of the statement.
2520 Never use untrusted input as a literal SQL argument - this is a massive
2521 security risk (there is no way to check literal snippets for SQL
2522 injections and other nastyness). If you need to deal with untrusted input
2523 use literal SQL with placeholders as described next.
2525 =head3 Literal SQL with placeholders and bind values (subqueries)
2527 If the literal SQL to be inserted has placeholders and bind values,
2528 use a reference to an arrayref (yes this is a double reference --
2529 not so common, but perfectly legal Perl). For example, to find a date
2530 in Postgres you can use something like this:
2533 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2538 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2541 Note that you must pass the bind values in the same format as they are returned
2542 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2543 to C<columns>, you must provide the bind values in the
2544 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2545 scalar value; most commonly the column name, but you can use any scalar value
2546 (including references and blessed references), L<SQL::Abstract> will simply
2547 pass it through intact. So if C<bindtype> is set to C<columns> the above
2548 example will look like:
2551 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2554 Literal SQL is especially useful for nesting parenthesized clauses in the
2555 main SQL query. Here is a first example:
2557 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2561 bar => \["IN ($sub_stmt)" => @sub_bind],
2566 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2567 WHERE c2 < ? AND c3 LIKE ?))";
2568 @bind = (1234, 100, "foo%");
2570 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2571 are expressed in the same way. Of course the C<$sub_stmt> and
2572 its associated bind values can be generated through a former call
2575 my ($sub_stmt, @sub_bind)
2576 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2577 c3 => {-like => "foo%"}});
2580 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2583 In the examples above, the subquery was used as an operator on a column;
2584 but the same principle also applies for a clause within the main C<%where>
2585 hash, like an EXISTS subquery:
2587 my ($sub_stmt, @sub_bind)
2588 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2589 my %where = ( -and => [
2591 \["EXISTS ($sub_stmt)" => @sub_bind],
2596 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2597 WHERE c1 = ? AND c2 > t0.c0))";
2601 Observe that the condition on C<c2> in the subquery refers to
2602 column C<t0.c0> of the main query: this is I<not> a bind
2603 value, so we have to express it through a scalar ref.
2604 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2605 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2606 what we wanted here.
2608 Finally, here is an example where a subquery is used
2609 for expressing unary negation:
2611 my ($sub_stmt, @sub_bind)
2612 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2613 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2615 lname => {like => '%son%'},
2616 \["NOT ($sub_stmt)" => @sub_bind],
2621 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2622 @bind = ('%son%', 10, 20)
2624 =head3 Deprecated usage of Literal SQL
2626 Below are some examples of archaic use of literal SQL. It is shown only as
2627 reference for those who deal with legacy code. Each example has a much
2628 better, cleaner and safer alternative that users should opt for in new code.
2634 my %where = ( requestor => \'IS NOT NULL' )
2636 $stmt = "WHERE requestor IS NOT NULL"
2638 This used to be the way of generating NULL comparisons, before the handling
2639 of C<undef> got formalized. For new code please use the superior syntax as
2640 described in L</Tests for NULL values>.
2644 my %where = ( requestor => \'= submitter' )
2646 $stmt = "WHERE requestor = submitter"
2648 This used to be the only way to compare columns. Use the superior L</-ident>
2649 method for all new code. For example an identifier declared in such a way
2650 will be properly quoted if L</quote_char> is properly set, while the legacy
2651 form will remain as supplied.
2655 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2657 $stmt = "WHERE completed > ? AND is_ready"
2658 @bind = ('2012-12-21')
2660 Using an empty string literal used to be the only way to express a boolean.
2661 For all new code please use the much more readable
2662 L<-bool|/Unary operators: bool> operator.
2668 These pages could go on for a while, since the nesting of the data
2669 structures this module can handle are pretty much unlimited (the
2670 module implements the C<WHERE> expansion as a recursive function
2671 internally). Your best bet is to "play around" with the module a
2672 little to see how the data structures behave, and choose the best
2673 format for your data based on that.
2675 And of course, all the values above will probably be replaced with
2676 variables gotten from forms or the command line. After all, if you
2677 knew everything ahead of time, you wouldn't have to worry about
2678 dynamically-generating SQL and could just hardwire it into your
2681 =head1 ORDER BY CLAUSES
2683 Some functions take an order by clause. This can either be a scalar (just a
2684 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2685 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2688 Given | Will Generate
2689 ---------------------------------------------------------------
2691 'colA' | ORDER BY colA
2693 [qw/colA colB/] | ORDER BY colA, colB
2695 {-asc => 'colA'} | ORDER BY colA ASC
2697 {-desc => 'colB'} | ORDER BY colB DESC
2699 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2701 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2703 \'colA DESC' | ORDER BY colA DESC
2705 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2706 | /* ...with $x bound to ? */
2709 { -asc => 'colA' }, | colA ASC,
2710 { -desc => [qw/colB/] }, | colB DESC,
2711 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2712 \'colE DESC', | colE DESC,
2713 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2714 ] | /* ...with $x bound to ? */
2715 ===============================================================
2719 =head1 SPECIAL OPERATORS
2721 my $sqlmaker = SQL::Abstract->new(special_ops => [
2725 my ($self, $field, $op, $arg) = @_;
2731 handler => 'method_name',
2735 A "special operator" is a SQL syntactic clause that can be
2736 applied to a field, instead of a usual binary operator.
2739 WHERE field IN (?, ?, ?)
2740 WHERE field BETWEEN ? AND ?
2741 WHERE MATCH(field) AGAINST (?, ?)
2743 Special operators IN and BETWEEN are fairly standard and therefore
2744 are builtin within C<SQL::Abstract> (as the overridable methods
2745 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2746 like the MATCH .. AGAINST example above which is specific to MySQL,
2747 you can write your own operator handlers - supply a C<special_ops>
2748 argument to the C<new> method. That argument takes an arrayref of
2749 operator definitions; each operator definition is a hashref with two
2756 the regular expression to match the operator
2760 Either a coderef or a plain scalar method name. In both cases
2761 the expected return is C<< ($sql, @bind) >>.
2763 When supplied with a method name, it is simply called on the
2764 L<SQL::Abstract> object as:
2766 $self->$method_name($field, $op, $arg)
2770 $field is the LHS of the operator
2771 $op is the part that matched the handler regex
2774 When supplied with a coderef, it is called as:
2776 $coderef->($self, $field, $op, $arg)
2781 For example, here is an implementation
2782 of the MATCH .. AGAINST syntax for MySQL
2784 my $sqlmaker = SQL::Abstract->new(special_ops => [
2786 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2787 {regex => qr/^match$/i,
2789 my ($self, $field, $op, $arg) = @_;
2790 $arg = [$arg] if not ref $arg;
2791 my $label = $self->_quote($field);
2792 my ($placeholder) = $self->_convert('?');
2793 my $placeholders = join ", ", (($placeholder) x @$arg);
2794 my $sql = $self->_sqlcase('match') . " ($label) "
2795 . $self->_sqlcase('against') . " ($placeholders) ";
2796 my @bind = $self->_bindtype($field, @$arg);
2797 return ($sql, @bind);
2804 =head1 UNARY OPERATORS
2806 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2810 my ($self, $op, $arg) = @_;
2816 handler => 'method_name',
2820 A "unary operator" is a SQL syntactic clause that can be
2821 applied to a field - the operator goes before the field
2823 You can write your own operator handlers - supply a C<unary_ops>
2824 argument to the C<new> method. That argument takes an arrayref of
2825 operator definitions; each operator definition is a hashref with two
2832 the regular expression to match the operator
2836 Either a coderef or a plain scalar method name. In both cases
2837 the expected return is C<< $sql >>.
2839 When supplied with a method name, it is simply called on the
2840 L<SQL::Abstract> object as:
2842 $self->$method_name($op, $arg)
2846 $op is the part that matched the handler regex
2847 $arg is the RHS or argument of the operator
2849 When supplied with a coderef, it is called as:
2851 $coderef->($self, $op, $arg)
2859 Thanks to some benchmarking by Mark Stosberg, it turns out that
2860 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2861 I must admit this wasn't an intentional design issue, but it's a
2862 byproduct of the fact that you get to control your C<DBI> handles
2865 To maximize performance, use a code snippet like the following:
2867 # prepare a statement handle using the first row
2868 # and then reuse it for the rest of the rows
2870 for my $href (@array_of_hashrefs) {
2871 $stmt ||= $sql->insert('table', $href);
2872 $sth ||= $dbh->prepare($stmt);
2873 $sth->execute($sql->values($href));
2876 The reason this works is because the keys in your C<$href> are sorted
2877 internally by B<SQL::Abstract>. Thus, as long as your data retains
2878 the same structure, you only have to generate the SQL the first time
2879 around. On subsequent queries, simply use the C<values> function provided
2880 by this module to return your values in the correct order.
2882 However this depends on the values having the same type - if, for
2883 example, the values of a where clause may either have values
2884 (resulting in sql of the form C<column = ?> with a single bind
2885 value), or alternatively the values might be C<undef> (resulting in
2886 sql of the form C<column IS NULL> with no bind value) then the
2887 caching technique suggested will not work.
2891 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2892 really like this part (I do, at least). Building up a complex query
2893 can be as simple as the following:
2900 use CGI::FormBuilder;
2903 my $form = CGI::FormBuilder->new(...);
2904 my $sql = SQL::Abstract->new;
2906 if ($form->submitted) {
2907 my $field = $form->field;
2908 my $id = delete $field->{id};
2909 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2912 Of course, you would still have to connect using C<DBI> to run the
2913 query, but the point is that if you make your form look like your
2914 table, the actual query script can be extremely simplistic.
2916 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2917 a fast interface to returning and formatting data. I frequently
2918 use these three modules together to write complex database query
2919 apps in under 50 lines.
2921 =head1 HOW TO CONTRIBUTE
2923 Contributions are always welcome, in all usable forms (we especially
2924 welcome documentation improvements). The delivery methods include git-
2925 or unified-diff formatted patches, GitHub pull requests, or plain bug
2926 reports either via RT or the Mailing list. Contributors are generally
2927 granted full access to the official repository after their first several
2928 patches pass successful review.
2930 This project is maintained in a git repository. The code and related tools are
2931 accessible at the following locations:
2935 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2937 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2939 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2941 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2947 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2948 Great care has been taken to preserve the I<published> behavior
2949 documented in previous versions in the 1.* family; however,
2950 some features that were previously undocumented, or behaved
2951 differently from the documentation, had to be changed in order
2952 to clarify the semantics. Hence, client code that was relying
2953 on some dark areas of C<SQL::Abstract> v1.*
2954 B<might behave differently> in v1.50.
2956 The main changes are:
2962 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2966 support for the { operator => \"..." } construct (to embed literal SQL)
2970 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2974 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2978 defensive programming: check arguments
2982 fixed bug with global logic, which was previously implemented
2983 through global variables yielding side-effects. Prior versions would
2984 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2985 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2986 Now this is interpreted
2987 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2992 fixed semantics of _bindtype on array args
2996 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2997 we just avoid shifting arrays within that tree.
3001 dropped the C<_modlogic> function
3005 =head1 ACKNOWLEDGEMENTS
3007 There are a number of individuals that have really helped out with
3008 this module. Unfortunately, most of them submitted bugs via CPAN
3009 so I have no idea who they are! But the people I do know are:
3011 Ash Berlin (order_by hash term support)
3012 Matt Trout (DBIx::Class support)
3013 Mark Stosberg (benchmarking)
3014 Chas Owens (initial "IN" operator support)
3015 Philip Collins (per-field SQL functions)
3016 Eric Kolve (hashref "AND" support)
3017 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3018 Dan Kubb (support for "quote_char" and "name_sep")
3019 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3020 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3021 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3022 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3023 Oliver Charles (support for "RETURNING" after "INSERT")
3029 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3033 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3035 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3037 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3038 While not an official support venue, C<DBIx::Class> makes heavy use of
3039 C<SQL::Abstract>, and as such list members there are very familiar with
3040 how to create queries.
3044 This module is free software; you may copy this under the same
3045 terms as perl itself (either the GNU General Public License or
3046 the Artistic License)