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 $opt{injection_guard} ||= qr/
188 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
192 $opt{expand_unary} = {};
194 return bless \%opt, $class;
197 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
198 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
200 sub _assert_pass_injection_guard {
201 if ($_[1] =~ $_[0]->{injection_guard}) {
202 my $class = ref $_[0];
203 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
204 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
205 . "{injection_guard} attribute to ${class}->new()"
210 #======================================================================
212 #======================================================================
216 my $table = $self->_table(shift);
217 my $data = shift || return;
220 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
221 my ($sql, @bind) = $self->$method($data);
222 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
224 if ($options->{returning}) {
225 my ($s, @b) = $self->_insert_returning($options);
230 return wantarray ? ($sql, @bind) : $sql;
233 # So that subclasses can override INSERT ... RETURNING separately from
234 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
235 sub _insert_returning { shift->_returning(@_) }
238 my ($self, $options) = @_;
240 my $f = $options->{returning};
242 my ($sql, @bind) = $self->render_aqt(
243 $self->_expand_maybe_list_expr($f, undef, -ident)
246 ? $self->_sqlcase(' returning ') . $sql
247 : ($self->_sqlcase(' returning ').$sql, @bind);
250 sub _insert_HASHREF { # explicit list of fields and then values
251 my ($self, $data) = @_;
253 my @fields = sort keys %$data;
255 my ($sql, @bind) = $self->_insert_values($data);
258 $_ = $self->_quote($_) foreach @fields;
259 $sql = "( ".join(", ", @fields).") ".$sql;
261 return ($sql, @bind);
264 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
265 my ($self, $data) = @_;
267 # no names (arrayref) so can't generate bindtype
268 $self->{bindtype} ne 'columns'
269 or belch "can't do 'columns' bindtype when called with arrayref";
271 my (@values, @all_bind);
272 foreach my $value (@$data) {
273 my ($values, @bind) = $self->_insert_value(undef, $value);
274 push @values, $values;
275 push @all_bind, @bind;
277 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
278 return ($sql, @all_bind);
281 sub _insert_ARRAYREFREF { # literal SQL with bind
282 my ($self, $data) = @_;
284 my ($sql, @bind) = @${$data};
285 $self->_assert_bindval_matches_bindtype(@bind);
287 return ($sql, @bind);
291 sub _insert_SCALARREF { # literal SQL without bind
292 my ($self, $data) = @_;
298 my ($self, $data) = @_;
300 my (@values, @all_bind);
301 foreach my $column (sort keys %$data) {
302 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
303 push @values, $values;
304 push @all_bind, @bind;
306 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
307 return ($sql, @all_bind);
311 my ($self, $column, $v) = @_;
313 return $self->render_aqt(
314 $self->_expand_insert_value($column, $v)
318 sub _expand_insert_value {
319 my ($self, $column, $v) = @_;
321 if (ref($v) eq 'ARRAY') {
322 if ($self->{array_datatypes}) {
323 return +{ -bind => [ $column, $v ] };
325 my ($sql, @bind) = @$v;
326 $self->_assert_bindval_matches_bindtype(@bind);
327 return +{ -literal => $v };
329 if (ref($v) eq 'HASH') {
330 if (grep !/^-/, keys %$v) {
331 belch "HASH ref as bind value in insert is not supported";
332 return +{ -bind => [ $column, $v ] };
336 return +{ -bind => [ $column, undef ] };
338 local our $Cur_Col_Meta = $column;
339 return $self->expand_expr($v);
344 #======================================================================
346 #======================================================================
351 my $table = $self->_table(shift);
352 my $data = shift || return;
356 # first build the 'SET' part of the sql statement
357 puke "Unsupported data type specified to \$sql->update"
358 unless ref $data eq 'HASH';
360 my ($sql, @all_bind) = $self->_update_set_values($data);
361 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
365 my($where_sql, @where_bind) = $self->where($where);
367 push @all_bind, @where_bind;
370 if ($options->{returning}) {
371 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
372 $sql .= $returning_sql;
373 push @all_bind, @returning_bind;
376 return wantarray ? ($sql, @all_bind) : $sql;
379 sub _update_set_values {
380 my ($self, $data) = @_;
382 return $self->render_aqt(
383 $self->_expand_update_set_values($data),
387 sub _expand_update_set_values {
388 my ($self, $data) = @_;
389 $self->_expand_maybe_list_expr( [
392 $set = { -bind => $_ } unless defined $set;
393 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
399 ? ($self->{array_datatypes}
400 ? [ $k, +{ -bind => [ $k, $v ] } ]
401 : [ $k, +{ -literal => $v } ])
403 local our $Cur_Col_Meta = $k;
404 [ $k, $self->_expand_expr($v) ]
411 # So that subclasses can override UPDATE ... RETURNING separately from
413 sub _update_returning { shift->_returning(@_) }
417 #======================================================================
419 #======================================================================
424 my $table = $self->_table(shift);
425 my $fields = shift || '*';
429 my ($fields_sql, @bind) = $self->_select_fields($fields);
431 my ($where_sql, @where_bind) = $self->where($where, $order);
432 push @bind, @where_bind;
434 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
435 $self->_sqlcase('from'), $table)
438 return wantarray ? ($sql, @bind) : $sql;
442 my ($self, $fields) = @_;
443 return $fields unless ref($fields);
444 return $self->render_aqt(
445 $self->_expand_maybe_list_expr($fields, undef, '-ident')
449 #======================================================================
451 #======================================================================
456 my $table = $self->_table(shift);
460 my($where_sql, @bind) = $self->where($where);
461 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
463 if ($options->{returning}) {
464 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
465 $sql .= $returning_sql;
466 push @bind, @returning_bind;
469 return wantarray ? ($sql, @bind) : $sql;
472 # So that subclasses can override DELETE ... RETURNING separately from
474 sub _delete_returning { shift->_returning(@_) }
478 #======================================================================
480 #======================================================================
484 # Finally, a separate routine just to handle WHERE clauses
486 my ($self, $where, $order) = @_;
488 local $self->{convert_where} = $self->{convert};
491 my ($sql, @bind) = defined($where)
492 ? $self->_recurse_where($where)
494 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
498 my ($order_sql, @order_bind) = $self->_order_by($order);
500 push @bind, @order_bind;
503 return wantarray ? ($sql, @bind) : $sql;
507 my ($self, $expr, $default_scalar_to) = @_;
508 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
509 $self->_expand_expr($expr);
513 my ($self, $aqt) = @_;
514 my ($k, $v, @rest) = %$aqt;
516 if (my $meth = $self->{render}{$k}) {
517 return $self->$meth($v);
519 die "notreached: $k";
523 my ($self, $expr) = @_;
524 $self->render_aqt($self->expand_expr($expr));
528 my ($self, $expr, $logic) = @_;
529 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
530 return undef unless defined($expr);
531 if (ref($expr) eq 'HASH') {
532 if (keys %$expr > 1) {
536 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
540 return undef unless keys %$expr;
541 return $self->_expand_expr_hashpair(%$expr, $logic);
543 if (ref($expr) eq 'ARRAY') {
544 my $logic = lc($logic || $self->{logic});
545 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
548 (ref($_) eq 'ARRAY' and @$_)
549 or (ref($_) eq 'HASH' and %$_)
555 while (my ($el) = splice @expr, 0, 1) {
556 puke "Supplying an empty left hand side argument is not supported in array-pairs"
557 unless defined($el) and length($el);
558 my $elref = ref($el);
560 local $Expand_Depth = 0;
561 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
562 } elsif ($elref eq 'ARRAY') {
563 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
564 } elsif (my $l = is_literal_value($el)) {
565 push @res, { -literal => $l };
566 } elsif ($elref eq 'HASH') {
567 local $Expand_Depth = 0;
568 push @res, grep defined, $self->_expand_expr($el) if %$el;
573 return { -op => [ $logic, @res ] };
575 if (my $literal = is_literal_value($expr)) {
576 return +{ -literal => $literal };
578 if (!ref($expr) or Scalar::Util::blessed($expr)) {
579 if (my $d = our $Default_Scalar_To) {
580 return $self->_expand_expr({ $d => $expr });
582 if (my $m = our $Cur_Col_Meta) {
583 return +{ -bind => [ $m, $expr ] };
585 return +{ -bind => [ undef, $expr ] };
590 sub _expand_expr_hashpair {
591 my ($self, $k, $v, $logic) = @_;
592 unless (defined($k) and length($k)) {
593 if (defined($k) and my $literal = is_literal_value($v)) {
594 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
595 return { -literal => $literal };
597 puke "Supplying an empty left hand side argument is not supported";
600 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
601 if ($k =~ s/ [_\s]? \d+ $//x ) {
602 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
603 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
606 # DBIx::Class requires a nest warning to be emitted once but the private
607 # method it overrode to do so no longer exists
608 if ($self->{is_dbic_sqlmaker}) {
609 unless (our $Nest_Warned) {
611 "-nest in search conditions is deprecated, you most probably wanted:\n"
612 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
617 return $self->_expand_expr($v);
621 return $self->_expand_expr($v);
623 puke "-bool => undef not supported" unless defined($v);
624 return $self->_expand_ident(-ident => $v);
627 return { -op => [ 'not', $self->_expand_expr($v) ] };
629 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
632 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
635 if (my ($logic) = $k =~ /^-(and|or)$/i) {
636 if (ref($v) eq 'HASH') {
637 return $self->_expand_expr($v, $logic);
639 if (ref($v) eq 'ARRAY') {
640 return $self->_expand_expr($v, $logic);
645 $op =~ s/^-// if length($op) > 1;
647 # top level special ops are illegal in general
648 # note that, arguably, if it makes no sense at top level, it also
649 # makes no sense on the other side of an = sign or similar but DBIC
650 # gets disappointingly upset if I disallow it
652 (our $Expand_Depth) == 1
653 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
655 puke "Illegal use of top-level '-$op'"
657 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
658 return { -op => [ $op, $v ] };
661 if ($k eq '-value') {
662 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
664 if ($k eq '-ident') {
665 return $self->_expand_ident(-ident => $v);
667 if (my $custom = $self->{expand_unary}{$k}) {
668 return $self->$custom($v);
670 if ($self->{render}{$k}) {
676 and (keys %$v)[0] =~ /^-/
678 my ($func) = $k =~ /^-(.*)$/;
679 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
680 return +{ -op => [ $func, $self->_expand_expr($v) ] };
682 return +{ -func => [ $func, $self->_expand_expr($v) ] };
684 if (!ref($v) or is_literal_value($v)) {
685 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
692 and exists $v->{-value}
693 and not defined $v->{-value}
696 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
698 if (!ref($v) or Scalar::Util::blessed($v)) {
699 my $d = our $Default_Scalar_To;
703 $self->_expand_ident(-ident => $k),
705 ? $self->_expand_expr($d => $v)
706 : { -bind => [ $k, $v ] }
711 if (ref($v) eq 'HASH') {
715 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
719 return undef unless keys %$v;
721 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
722 $self->_assert_pass_injection_guard($op);
723 if ($op =~ s/ [_\s]? \d+ $//x ) {
724 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
725 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
727 if ($op =~ /^(?:not )?between$/) {
728 local our $Cur_Col_Meta = $k;
729 my @rhs = map $self->_expand_expr($_),
730 ref($vv) eq 'ARRAY' ? @$vv : $vv;
732 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
734 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
736 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
740 $self->_expand_ident(-ident => $k),
744 if ($op =~ /^(?:not )?in$/) {
745 if (my $literal = is_literal_value($vv)) {
746 my ($sql, @bind) = @$literal;
747 my $opened_sql = $self->_open_outer_paren($sql);
749 $op, $self->_expand_ident(-ident => $k),
750 [ { -literal => [ $opened_sql, @bind ] } ]
754 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
755 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
756 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
757 . 'will emit the logically correct SQL instead of raising this exception)'
759 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
761 my @rhs = map $self->_expand_expr($_),
762 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
763 map { defined($_) ? $_: puke($undef_err) }
764 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
765 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
769 $self->_expand_ident(-ident => $k),
773 if ($op eq 'ident') {
774 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
775 puke "-$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
779 $self->_expand_ident(-ident => $k),
780 $self->_expand_ident(-ident => $vv),
783 if ($op eq 'value') {
784 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
787 $self->_expand_ident(-ident => $k),
788 { -bind => [ $k, $vv ] }
791 if ($op =~ /^is(?: not)?$/) {
792 puke "$op can only take undef as argument"
796 and exists($vv->{-value})
797 and !defined($vv->{-value})
799 return +{ -op => [ $op.' null', $self->_expand_ident(-ident => $k) ] };
801 if ($op =~ /^(and|or)$/) {
802 if (ref($vv) eq 'HASH') {
805 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
810 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
811 return { -op => [ $op, $self->_expand_ident(-ident => $k), $vv ] };
813 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
816 $self->_expand_ident(-ident => $k),
817 { -op => [ $op, $vv ] }
820 if (ref($vv) eq 'ARRAY') {
821 my ($logic, @values) = (
822 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
827 $op =~ $self->{inequality_op}
828 or $op =~ $self->{not_like_op}
830 if (lc($logic) eq '-or' and @values > 1) {
831 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
832 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
833 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
838 # try to DWIM on equality operators
840 $op =~ $self->{equality_op} ? $self->sqlfalse
841 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
842 : $op =~ $self->{inequality_op} ? $self->sqltrue
843 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
844 : puke "operator '$op' applied on an empty array (field '$k')";
848 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
856 and exists $vv->{-value}
857 and not defined $vv->{-value}
861 $op =~ /^not$/i ? 'is not' # legacy
862 : $op =~ $self->{equality_op} ? 'is'
863 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
864 : $op =~ $self->{inequality_op} ? 'is not'
865 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
866 : puke "unexpected operator '$op' with undef operand";
867 return +{ -op => [ $is.' null', $self->_expand_ident(-ident => $k) ] };
869 local our $Cur_Col_Meta = $k;
872 $self->_expand_ident(-ident => $k),
873 $self->_expand_expr($vv)
876 if (ref($v) eq 'ARRAY') {
877 return $self->sqlfalse unless @$v;
878 $self->_debug("ARRAY($k) means distribute over elements");
880 $v->[0] =~ /^-((?:and|or))$/i
881 ? ($v = [ @{$v}[1..$#$v] ], $1)
882 : ($self->{logic} || 'or')
886 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
889 if (my $literal = is_literal_value($v)) {
891 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
894 my ($sql, @bind) = @$literal;
895 if ($self->{bindtype} eq 'columns') {
897 $self->_assert_bindval_matches_bindtype($_);
900 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
906 my ($self, undef, $body) = @_;
907 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
908 ref($body) ? @$body : $body;
909 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
910 unless ($self->{quote_char}) {
911 $self->_assert_pass_injection_guard($_) for @parts;
913 return +{ -ident => \@parts };
917 my ($self, $where, $logic) = @_;
919 # Special case: top level simple string treated as literal
921 my $where_exp = (ref($where)
922 ? $self->_expand_expr($where, $logic)
923 : { -literal => [ $where ] });
925 # dispatch expanded expression
927 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
928 # DBIx::Class used to call _recurse_where in scalar context
929 # something else might too...
931 return ($sql, @bind);
934 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
940 my ($self, $ident) = @_;
942 return $self->_convert($self->_quote($ident));
945 my %unop_postfix = map +($_ => 1),
946 'is null', 'is not null',
954 my ($self, $args) = @_;
955 my ($left, $low, $high) = @$args;
956 my ($rhsql, @rhbind) = do {
958 puke "Single arg to between must be a literal"
959 unless $low->{-literal};
962 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
963 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
964 @{$l}[1..$#$l], @{$h}[1..$#$h])
967 my ($lhsql, @lhbind) = $self->render_aqt($left);
969 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
973 }), 'between', 'not between'),
977 my ($self, $args) = @_;
978 my ($lhs, $rhs) = @$args;
981 my ($sql, @bind) = $self->render_aqt($_);
982 push @in_bind, @bind;
985 my ($lhsql, @lbind) = $self->render_aqt($lhs);
987 $lhsql.' '.$self->_sqlcase($op).' ( '
998 my ($op, @args) = @$v;
999 $op =~ s/^-// if length($op) > 1;
1001 if (my $h = $special{$op}) {
1002 return $self->$h(\@args);
1004 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1005 if ($us and @args > 1) {
1006 puke "Special op '${op}' requires first value to be identifier"
1007 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1008 my $k = join(($self->{name_sep}||'.'), @$ident);
1009 local our $Expand_Depth = 1;
1010 return $self->${\($us->{handler})}($k, $op, $args[1]);
1012 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1013 return $self->${\($us->{handler})}($op, $args[0]);
1015 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1016 if (@args == 1 and $op !~ /^(and|or)$/) {
1017 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1018 my $op_sql = $self->_sqlcase($final_op);
1020 $unop_postfix{lc($final_op)}
1021 ? "${expr_sql} ${op_sql}"
1022 : "${op_sql} ${expr_sql}"
1024 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1026 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1027 return '' unless @parts;
1028 my $is_andor = !!($op =~ /^(and|or)$/);
1029 return @{$parts[0]} if $is_andor and @parts == 1;
1030 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1031 ' '.$self->_sqlcase($final_op).' ',
1036 map @{$_}[1..$#$_], @parts
1043 my ($self, $list) = @_;
1044 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
1045 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1049 my ($self, $rest) = @_;
1050 my ($func, @args) = @$rest;
1054 push @arg_sql, shift @x;
1056 } map [ $self->render_aqt($_) ], @args;
1057 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1061 my ($self, $bind) = @_;
1062 return ($self->_convert('?'), $self->_bindtype(@$bind));
1065 sub _render_literal {
1066 my ($self, $literal) = @_;
1067 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1071 # Some databases (SQLite) treat col IN (1, 2) different from
1072 # col IN ( (1, 2) ). Use this to strip all outer parens while
1073 # adding them back in the corresponding method
1074 sub _open_outer_paren {
1075 my ($self, $sql) = @_;
1077 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1079 # there are closing parens inside, need the heavy duty machinery
1080 # to reevaluate the extraction starting from $sql (full reevaluation)
1081 if ($inner =~ /\)/) {
1082 require Text::Balanced;
1084 my (undef, $remainder) = do {
1085 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1087 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1090 # the entire expression needs to be a balanced bracketed thing
1091 # (after an extract no remainder sans trailing space)
1092 last if defined $remainder and $remainder =~ /\S/;
1102 #======================================================================
1104 #======================================================================
1106 sub _expand_order_by {
1107 my ($self, $arg) = @_;
1109 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1111 my $expander = sub {
1112 my ($self, $dir, $expr) = @_;
1113 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1114 foreach my $arg (@to_expand) {
1118 and grep /^-(asc|desc)$/, keys %$arg
1120 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1123 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1124 map $self->expand_expr($_, -ident),
1125 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1126 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1129 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1130 sub { shift->$expander(asc => @_) },
1131 sub { shift->$expander(desc => @_) },
1134 return $self->$expander(undef, $arg);
1138 my ($self, $arg) = @_;
1140 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1142 my ($sql, @bind) = $self->render_aqt($expanded);
1144 return '' unless length($sql);
1146 my $final_sql = $self->_sqlcase(' order by ').$sql;
1148 return wantarray ? ($final_sql, @bind) : $final_sql;
1151 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1153 sub _order_by_chunks {
1154 my ($self, $arg) = @_;
1156 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1158 return $self->_chunkify_order_by($expanded);
1161 sub _chunkify_order_by {
1162 my ($self, $expanded) = @_;
1164 return grep length, $self->render_aqt($expanded)
1165 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1168 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1169 return map $self->_chunkify_order_by($_), @$l;
1171 return [ $self->render_aqt($_) ];
1175 #======================================================================
1176 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1177 #======================================================================
1183 $self->_expand_maybe_list_expr($from, undef, -ident)
1188 #======================================================================
1190 #======================================================================
1192 sub _expand_maybe_list_expr {
1193 my ($self, $expr, $logic, $default) = @_;
1195 if (ref($expr) eq 'ARRAY') {
1197 map $self->expand_expr($_, $default), @$expr
1204 return $self->expand_expr($e, $default);
1207 # highly optimized, as it's called way too often
1209 # my ($self, $label) = @_;
1211 return '' unless defined $_[1];
1212 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1213 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1215 unless ($_[0]->{quote_char}) {
1216 if (ref($_[1]) eq 'ARRAY') {
1217 return join($_[0]->{name_sep}||'.', @{$_[1]});
1219 $_[0]->_assert_pass_injection_guard($_[1]);
1224 my $qref = ref $_[0]->{quote_char};
1226 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1227 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1228 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1230 my $esc = $_[0]->{escape_char} || $r;
1232 # parts containing * are naturally unquoted
1234 $_[0]->{name_sep}||'',
1238 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1240 (ref($_[1]) eq 'ARRAY'
1244 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1252 # Conversion, if applicable
1254 #my ($self, $arg) = @_;
1255 if ($_[0]->{convert_where}) {
1256 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1263 #my ($self, $col, @vals) = @_;
1264 # called often - tighten code
1265 return $_[0]->{bindtype} eq 'columns'
1266 ? map {[$_[1], $_]} @_[2 .. $#_]
1271 # Dies if any element of @bind is not in [colname => value] format
1272 # if bindtype is 'columns'.
1273 sub _assert_bindval_matches_bindtype {
1274 # my ($self, @bind) = @_;
1276 if ($self->{bindtype} eq 'columns') {
1278 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1279 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1285 sub _join_sql_clauses {
1286 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1288 if (@$clauses_aref > 1) {
1289 my $join = " " . $self->_sqlcase($logic) . " ";
1290 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1291 return ($sql, @$bind_aref);
1293 elsif (@$clauses_aref) {
1294 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1297 return (); # if no SQL, ignore @$bind_aref
1302 # Fix SQL case, if so requested
1304 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1305 # don't touch the argument ... crooked logic, but let's not change it!
1306 return $_[0]->{case} ? $_[1] : uc($_[1]);
1310 #======================================================================
1311 # DISPATCHING FROM REFKIND
1312 #======================================================================
1315 my ($self, $data) = @_;
1317 return 'UNDEF' unless defined $data;
1319 # blessed objects are treated like scalars
1320 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1322 return 'SCALAR' unless $ref;
1325 while ($ref eq 'REF') {
1327 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1331 return ($ref||'SCALAR') . ('REF' x $n_steps);
1335 my ($self, $data) = @_;
1336 my @try = ($self->_refkind($data));
1337 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1338 push @try, 'FALLBACK';
1342 sub _METHOD_FOR_refkind {
1343 my ($self, $meth_prefix, $data) = @_;
1346 for (@{$self->_try_refkind($data)}) {
1347 $method = $self->can($meth_prefix."_".$_)
1351 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1355 sub _SWITCH_refkind {
1356 my ($self, $data, $dispatch_table) = @_;
1359 for (@{$self->_try_refkind($data)}) {
1360 $coderef = $dispatch_table->{$_}
1364 puke "no dispatch entry for ".$self->_refkind($data)
1373 #======================================================================
1374 # VALUES, GENERATE, AUTOLOAD
1375 #======================================================================
1377 # LDNOTE: original code from nwiger, didn't touch code in that section
1378 # I feel the AUTOLOAD stuff should not be the default, it should
1379 # only be activated on explicit demand by user.
1383 my $data = shift || return;
1384 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1385 unless ref $data eq 'HASH';
1388 foreach my $k (sort keys %$data) {
1389 my $v = $data->{$k};
1390 $self->_SWITCH_refkind($v, {
1392 if ($self->{array_datatypes}) { # array datatype
1393 push @all_bind, $self->_bindtype($k, $v);
1395 else { # literal SQL with bind
1396 my ($sql, @bind) = @$v;
1397 $self->_assert_bindval_matches_bindtype(@bind);
1398 push @all_bind, @bind;
1401 ARRAYREFREF => sub { # literal SQL with bind
1402 my ($sql, @bind) = @${$v};
1403 $self->_assert_bindval_matches_bindtype(@bind);
1404 push @all_bind, @bind;
1406 SCALARREF => sub { # literal SQL without bind
1408 SCALAR_or_UNDEF => sub {
1409 push @all_bind, $self->_bindtype($k, $v);
1420 my(@sql, @sqlq, @sqlv);
1424 if ($ref eq 'HASH') {
1425 for my $k (sort keys %$_) {
1428 my $label = $self->_quote($k);
1429 if ($r eq 'ARRAY') {
1430 # literal SQL with bind
1431 my ($sql, @bind) = @$v;
1432 $self->_assert_bindval_matches_bindtype(@bind);
1433 push @sqlq, "$label = $sql";
1435 } elsif ($r eq 'SCALAR') {
1436 # literal SQL without bind
1437 push @sqlq, "$label = $$v";
1439 push @sqlq, "$label = ?";
1440 push @sqlv, $self->_bindtype($k, $v);
1443 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1444 } elsif ($ref eq 'ARRAY') {
1445 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1448 if ($r eq 'ARRAY') { # literal SQL with bind
1449 my ($sql, @bind) = @$v;
1450 $self->_assert_bindval_matches_bindtype(@bind);
1453 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1454 # embedded literal SQL
1461 push @sql, '(' . join(', ', @sqlq) . ')';
1462 } elsif ($ref eq 'SCALAR') {
1466 # strings get case twiddled
1467 push @sql, $self->_sqlcase($_);
1471 my $sql = join ' ', @sql;
1473 # this is pretty tricky
1474 # if ask for an array, return ($stmt, @bind)
1475 # otherwise, s/?/shift @sqlv/ to put it inline
1477 return ($sql, @sqlv);
1479 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1480 ref $d ? $d->[1] : $d/e;
1489 # This allows us to check for a local, then _form, attr
1491 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1492 return $self->generate($name, @_);
1503 SQL::Abstract - Generate SQL from Perl data structures
1509 my $sql = SQL::Abstract->new;
1511 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1513 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1515 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1517 my($stmt, @bind) = $sql->delete($table, \%where);
1519 # Then, use these in your DBI statements
1520 my $sth = $dbh->prepare($stmt);
1521 $sth->execute(@bind);
1523 # Just generate the WHERE clause
1524 my($stmt, @bind) = $sql->where(\%where, $order);
1526 # Return values in the same order, for hashed queries
1527 # See PERFORMANCE section for more details
1528 my @bind = $sql->values(\%fieldvals);
1532 This module was inspired by the excellent L<DBIx::Abstract>.
1533 However, in using that module I found that what I really wanted
1534 to do was generate SQL, but still retain complete control over my
1535 statement handles and use the DBI interface. So, I set out to
1536 create an abstract SQL generation module.
1538 While based on the concepts used by L<DBIx::Abstract>, there are
1539 several important differences, especially when it comes to WHERE
1540 clauses. I have modified the concepts used to make the SQL easier
1541 to generate from Perl data structures and, IMO, more intuitive.
1542 The underlying idea is for this module to do what you mean, based
1543 on the data structures you provide it. The big advantage is that
1544 you don't have to modify your code every time your data changes,
1545 as this module figures it out.
1547 To begin with, an SQL INSERT is as easy as just specifying a hash
1548 of C<key=value> pairs:
1551 name => 'Jimbo Bobson',
1552 phone => '123-456-7890',
1553 address => '42 Sister Lane',
1554 city => 'St. Louis',
1555 state => 'Louisiana',
1558 The SQL can then be generated with this:
1560 my($stmt, @bind) = $sql->insert('people', \%data);
1562 Which would give you something like this:
1564 $stmt = "INSERT INTO people
1565 (address, city, name, phone, state)
1566 VALUES (?, ?, ?, ?, ?)";
1567 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1568 '123-456-7890', 'Louisiana');
1570 These are then used directly in your DBI code:
1572 my $sth = $dbh->prepare($stmt);
1573 $sth->execute(@bind);
1575 =head2 Inserting and Updating Arrays
1577 If your database has array types (like for example Postgres),
1578 activate the special option C<< array_datatypes => 1 >>
1579 when creating the C<SQL::Abstract> object.
1580 Then you may use an arrayref to insert and update database array types:
1582 my $sql = SQL::Abstract->new(array_datatypes => 1);
1584 planets => [qw/Mercury Venus Earth Mars/]
1587 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1591 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1593 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1596 =head2 Inserting and Updating SQL
1598 In order to apply SQL functions to elements of your C<%data> you may
1599 specify a reference to an arrayref for the given hash value. For example,
1600 if you need to execute the Oracle C<to_date> function on a value, you can
1601 say something like this:
1605 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1608 The first value in the array is the actual SQL. Any other values are
1609 optional and would be included in the bind values array. This gives
1612 my($stmt, @bind) = $sql->insert('people', \%data);
1614 $stmt = "INSERT INTO people (name, date_entered)
1615 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1616 @bind = ('Bill', '03/02/2003');
1618 An UPDATE is just as easy, all you change is the name of the function:
1620 my($stmt, @bind) = $sql->update('people', \%data);
1622 Notice that your C<%data> isn't touched; the module will generate
1623 the appropriately quirky SQL for you automatically. Usually you'll
1624 want to specify a WHERE clause for your UPDATE, though, which is
1625 where handling C<%where> hashes comes in handy...
1627 =head2 Complex where statements
1629 This module can generate pretty complicated WHERE statements
1630 easily. For example, simple C<key=value> pairs are taken to mean
1631 equality, and if you want to see if a field is within a set
1632 of values, you can use an arrayref. Let's say we wanted to
1633 SELECT some data based on this criteria:
1636 requestor => 'inna',
1637 worker => ['nwiger', 'rcwe', 'sfz'],
1638 status => { '!=', 'completed' }
1641 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1643 The above would give you something like this:
1645 $stmt = "SELECT * FROM tickets WHERE
1646 ( requestor = ? ) AND ( status != ? )
1647 AND ( worker = ? OR worker = ? OR worker = ? )";
1648 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1650 Which you could then use in DBI code like so:
1652 my $sth = $dbh->prepare($stmt);
1653 $sth->execute(@bind);
1659 The methods are simple. There's one for every major SQL operation,
1660 and a constructor you use first. The arguments are specified in a
1661 similar order for each method (table, then fields, then a where
1662 clause) to try and simplify things.
1664 =head2 new(option => 'value')
1666 The C<new()> function takes a list of options and values, and returns
1667 a new B<SQL::Abstract> object which can then be used to generate SQL
1668 through the methods below. The options accepted are:
1674 If set to 'lower', then SQL will be generated in all lowercase. By
1675 default SQL is generated in "textbook" case meaning something like:
1677 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1679 Any setting other than 'lower' is ignored.
1683 This determines what the default comparison operator is. By default
1684 it is C<=>, meaning that a hash like this:
1686 %where = (name => 'nwiger', email => 'nate@wiger.org');
1688 Will generate SQL like this:
1690 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1692 However, you may want loose comparisons by default, so if you set
1693 C<cmp> to C<like> you would get SQL such as:
1695 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1697 You can also override the comparison on an individual basis - see
1698 the huge section on L</"WHERE CLAUSES"> at the bottom.
1700 =item sqltrue, sqlfalse
1702 Expressions for inserting boolean values within SQL statements.
1703 By default these are C<1=1> and C<1=0>. They are used
1704 by the special operators C<-in> and C<-not_in> for generating
1705 correct SQL even when the argument is an empty array (see below).
1709 This determines the default logical operator for multiple WHERE
1710 statements in arrays or hashes. If absent, the default logic is "or"
1711 for arrays, and "and" for hashes. This means that a WHERE
1715 event_date => {'>=', '2/13/99'},
1716 event_date => {'<=', '4/24/03'},
1719 will generate SQL like this:
1721 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1723 This is probably not what you want given this query, though (look
1724 at the dates). To change the "OR" to an "AND", simply specify:
1726 my $sql = SQL::Abstract->new(logic => 'and');
1728 Which will change the above C<WHERE> to:
1730 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1732 The logic can also be changed locally by inserting
1733 a modifier in front of an arrayref:
1735 @where = (-and => [event_date => {'>=', '2/13/99'},
1736 event_date => {'<=', '4/24/03'} ]);
1738 See the L</"WHERE CLAUSES"> section for explanations.
1742 This will automatically convert comparisons using the specified SQL
1743 function for both column and value. This is mostly used with an argument
1744 of C<upper> or C<lower>, so that the SQL will have the effect of
1745 case-insensitive "searches". For example, this:
1747 $sql = SQL::Abstract->new(convert => 'upper');
1748 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1750 Will turn out the following SQL:
1752 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1754 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1755 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1756 not validate this option; it will just pass through what you specify verbatim).
1760 This is a kludge because many databases suck. For example, you can't
1761 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1762 Instead, you have to use C<bind_param()>:
1764 $sth->bind_param(1, 'reg data');
1765 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1767 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1768 which loses track of which field each slot refers to. Fear not.
1770 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1771 Currently, you can specify either C<normal> (default) or C<columns>. If you
1772 specify C<columns>, you will get an array that looks like this:
1774 my $sql = SQL::Abstract->new(bindtype => 'columns');
1775 my($stmt, @bind) = $sql->insert(...);
1778 [ 'column1', 'value1' ],
1779 [ 'column2', 'value2' ],
1780 [ 'column3', 'value3' ],
1783 You can then iterate through this manually, using DBI's C<bind_param()>.
1785 $sth->prepare($stmt);
1788 my($col, $data) = @$_;
1789 if ($col eq 'details' || $col eq 'comments') {
1790 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1791 } elsif ($col eq 'image') {
1792 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1794 $sth->bind_param($i, $data);
1798 $sth->execute; # execute without @bind now
1800 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1801 Basically, the advantage is still that you don't have to care which fields
1802 are or are not included. You could wrap that above C<for> loop in a simple
1803 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1804 get a layer of abstraction over manual SQL specification.
1806 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1807 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1808 will expect the bind values in this format.
1812 This is the character that a table or column name will be quoted
1813 with. By default this is an empty string, but you could set it to
1814 the character C<`>, to generate SQL like this:
1816 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1818 Alternatively, you can supply an array ref of two items, the first being the left
1819 hand quote character, and the second the right hand quote character. For
1820 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1821 that generates SQL like this:
1823 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1825 Quoting is useful if you have tables or columns names that are reserved
1826 words in your database's SQL dialect.
1830 This is the character that will be used to escape L</quote_char>s appearing
1831 in an identifier before it has been quoted.
1833 The parameter default in case of a single L</quote_char> character is the quote
1836 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1837 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1838 of the B<opening (left)> L</quote_char> within the identifier are currently left
1839 untouched. The default for opening-closing-style quotes may change in future
1840 versions, thus you are B<strongly encouraged> to specify the escape character
1845 This is the character that separates a table and column name. It is
1846 necessary to specify this when the C<quote_char> option is selected,
1847 so that tables and column names can be individually quoted like this:
1849 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1851 =item injection_guard
1853 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1854 column name specified in a query structure. This is a safety mechanism to avoid
1855 injection attacks when mishandling user input e.g.:
1857 my %condition_as_column_value_pairs = get_values_from_user();
1858 $sqla->select( ... , \%condition_as_column_value_pairs );
1860 If the expression matches an exception is thrown. Note that literal SQL
1861 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1863 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1865 =item array_datatypes
1867 When this option is true, arrayrefs in INSERT or UPDATE are
1868 interpreted as array datatypes and are passed directly
1870 When this option is false, arrayrefs are interpreted
1871 as literal SQL, just like refs to arrayrefs
1872 (but this behavior is for backwards compatibility; when writing
1873 new queries, use the "reference to arrayref" syntax
1879 Takes a reference to a list of "special operators"
1880 to extend the syntax understood by L<SQL::Abstract>.
1881 See section L</"SPECIAL OPERATORS"> for details.
1885 Takes a reference to a list of "unary operators"
1886 to extend the syntax understood by L<SQL::Abstract>.
1887 See section L</"UNARY OPERATORS"> for details.
1893 =head2 insert($table, \@values || \%fieldvals, \%options)
1895 This is the simplest function. You simply give it a table name
1896 and either an arrayref of values or hashref of field/value pairs.
1897 It returns an SQL INSERT statement and a list of bind values.
1898 See the sections on L</"Inserting and Updating Arrays"> and
1899 L</"Inserting and Updating SQL"> for information on how to insert
1900 with those data types.
1902 The optional C<\%options> hash reference may contain additional
1903 options to generate the insert SQL. Currently supported options
1910 Takes either a scalar of raw SQL fields, or an array reference of
1911 field names, and adds on an SQL C<RETURNING> statement at the end.
1912 This allows you to return data generated by the insert statement
1913 (such as row IDs) without performing another C<SELECT> statement.
1914 Note, however, this is not part of the SQL standard and may not
1915 be supported by all database engines.
1919 =head2 update($table, \%fieldvals, \%where, \%options)
1921 This takes a table, hashref of field/value pairs, and an optional
1922 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1924 See the sections on L</"Inserting and Updating Arrays"> and
1925 L</"Inserting and Updating SQL"> for information on how to insert
1926 with those data types.
1928 The optional C<\%options> hash reference may contain additional
1929 options to generate the update SQL. Currently supported options
1936 See the C<returning> option to
1937 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1941 =head2 select($source, $fields, $where, $order)
1943 This returns a SQL SELECT statement and associated list of bind values, as
1944 specified by the arguments:
1950 Specification of the 'FROM' part of the statement.
1951 The argument can be either a plain scalar (interpreted as a table
1952 name, will be quoted), or an arrayref (interpreted as a list
1953 of table names, joined by commas, quoted), or a scalarref
1954 (literal SQL, not quoted).
1958 Specification of the list of fields to retrieve from
1960 The argument can be either an arrayref (interpreted as a list
1961 of field names, will be joined by commas and quoted), or a
1962 plain scalar (literal SQL, not quoted).
1963 Please observe that this API is not as flexible as that of
1964 the first argument C<$source>, for backwards compatibility reasons.
1968 Optional argument to specify the WHERE part of the query.
1969 The argument is most often a hashref, but can also be
1970 an arrayref or plain scalar --
1971 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1975 Optional argument to specify the ORDER BY part of the query.
1976 The argument can be a scalar, a hashref or an arrayref
1977 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1983 =head2 delete($table, \%where, \%options)
1985 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1986 It returns an SQL DELETE statement and list of bind values.
1988 The optional C<\%options> hash reference may contain additional
1989 options to generate the delete SQL. Currently supported options
1996 See the C<returning> option to
1997 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2001 =head2 where(\%where, $order)
2003 This is used to generate just the WHERE clause. For example,
2004 if you have an arbitrary data structure and know what the
2005 rest of your SQL is going to look like, but want an easy way
2006 to produce a WHERE clause, use this. It returns an SQL WHERE
2007 clause and list of bind values.
2010 =head2 values(\%data)
2012 This just returns the values from the hash C<%data>, in the same
2013 order that would be returned from any of the other above queries.
2014 Using this allows you to markedly speed up your queries if you
2015 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2017 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2019 Warning: This is an experimental method and subject to change.
2021 This returns arbitrarily generated SQL. It's a really basic shortcut.
2022 It will return two different things, depending on return context:
2024 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2025 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2027 These would return the following:
2029 # First calling form
2030 $stmt = "CREATE TABLE test (?, ?)";
2031 @bind = (field1, field2);
2033 # Second calling form
2034 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2036 Depending on what you're trying to do, it's up to you to choose the correct
2037 format. In this example, the second form is what you would want.
2041 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2045 ALTER SESSION SET nls_date_format = 'MM/YY'
2047 You get the idea. Strings get their case twiddled, but everything
2048 else remains verbatim.
2050 =head1 EXPORTABLE FUNCTIONS
2052 =head2 is_plain_value
2054 Determines if the supplied argument is a plain value as understood by this
2059 =item * The value is C<undef>
2061 =item * The value is a non-reference
2063 =item * The value is an object with stringification overloading
2065 =item * The value is of the form C<< { -value => $anything } >>
2069 On failure returns C<undef>, on success returns a B<scalar> reference
2070 to the original supplied argument.
2076 The stringification overloading detection is rather advanced: it takes
2077 into consideration not only the presence of a C<""> overload, but if that
2078 fails also checks for enabled
2079 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2080 on either C<0+> or C<bool>.
2082 Unfortunately testing in the field indicates that this
2083 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2084 but only when very large numbers of stringifying objects are involved.
2085 At the time of writing ( Sep 2014 ) there is no clear explanation of
2086 the direct cause, nor is there a manageably small test case that reliably
2087 reproduces the problem.
2089 If you encounter any of the following exceptions in B<random places within
2090 your application stack> - this module may be to blame:
2092 Operation "ne": no method found,
2093 left argument in overloaded package <something>,
2094 right argument in overloaded package <something>
2098 Stub found while resolving method "???" overloading """" in package <something>
2100 If you fall victim to the above - please attempt to reduce the problem
2101 to something that could be sent to the L<SQL::Abstract developers
2102 |DBIx::Class/GETTING HELP/SUPPORT>
2103 (either publicly or privately). As a workaround in the meantime you can
2104 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2105 value, which will most likely eliminate your problem (at the expense of
2106 not being able to properly detect exotic forms of stringification).
2108 This notice and environment variable will be removed in a future version,
2109 as soon as the underlying problem is found and a reliable workaround is
2114 =head2 is_literal_value
2116 Determines if the supplied argument is a literal value as understood by this
2121 =item * C<\$sql_string>
2123 =item * C<\[ $sql_string, @bind_values ]>
2127 On failure returns C<undef>, on success returns an B<array> reference
2128 containing the unpacked version of the supplied literal SQL and bind values.
2130 =head1 WHERE CLAUSES
2134 This module uses a variation on the idea from L<DBIx::Abstract>. It
2135 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2136 module is that things in arrays are OR'ed, and things in hashes
2139 The easiest way to explain is to show lots of examples. After
2140 each C<%where> hash shown, it is assumed you used:
2142 my($stmt, @bind) = $sql->where(\%where);
2144 However, note that the C<%where> hash can be used directly in any
2145 of the other functions as well, as described above.
2147 =head2 Key-value pairs
2149 So, let's get started. To begin, a simple hash:
2153 status => 'completed'
2156 Is converted to SQL C<key = val> statements:
2158 $stmt = "WHERE user = ? AND status = ?";
2159 @bind = ('nwiger', 'completed');
2161 One common thing I end up doing is having a list of values that
2162 a field can be in. To do this, simply specify a list inside of
2167 status => ['assigned', 'in-progress', 'pending'];
2170 This simple code will create the following:
2172 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2173 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2175 A field associated to an empty arrayref will be considered a
2176 logical false and will generate 0=1.
2178 =head2 Tests for NULL values
2180 If the value part is C<undef> then this is converted to SQL <IS NULL>
2189 $stmt = "WHERE user = ? AND status IS NULL";
2192 To test if a column IS NOT NULL:
2196 status => { '!=', undef },
2199 =head2 Specific comparison operators
2201 If you want to specify a different type of operator for your comparison,
2202 you can use a hashref for a given column:
2206 status => { '!=', 'completed' }
2209 Which would generate:
2211 $stmt = "WHERE user = ? AND status != ?";
2212 @bind = ('nwiger', 'completed');
2214 To test against multiple values, just enclose the values in an arrayref:
2216 status => { '=', ['assigned', 'in-progress', 'pending'] };
2218 Which would give you:
2220 "WHERE status = ? OR status = ? OR status = ?"
2223 The hashref can also contain multiple pairs, in which case it is expanded
2224 into an C<AND> of its elements:
2228 status => { '!=', 'completed', -not_like => 'pending%' }
2231 # Or more dynamically, like from a form
2232 $where{user} = 'nwiger';
2233 $where{status}{'!='} = 'completed';
2234 $where{status}{'-not_like'} = 'pending%';
2236 # Both generate this
2237 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2238 @bind = ('nwiger', 'completed', 'pending%');
2241 To get an OR instead, you can combine it with the arrayref idea:
2245 priority => [ { '=', 2 }, { '>', 5 } ]
2248 Which would generate:
2250 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2251 @bind = ('2', '5', 'nwiger');
2253 If you want to include literal SQL (with or without bind values), just use a
2254 scalar reference or reference to an arrayref as the value:
2257 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2258 date_expires => { '<' => \"now()" }
2261 Which would generate:
2263 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2264 @bind = ('11/26/2008');
2267 =head2 Logic and nesting operators
2269 In the example above,
2270 there is a subtle trap if you want to say something like
2271 this (notice the C<AND>):
2273 WHERE priority != ? AND priority != ?
2275 Because, in Perl you I<can't> do this:
2277 priority => { '!=' => 2, '!=' => 1 }
2279 As the second C<!=> key will obliterate the first. The solution
2280 is to use the special C<-modifier> form inside an arrayref:
2282 priority => [ -and => {'!=', 2},
2286 Normally, these would be joined by C<OR>, but the modifier tells it
2287 to use C<AND> instead. (Hint: You can use this in conjunction with the
2288 C<logic> option to C<new()> in order to change the way your queries
2289 work by default.) B<Important:> Note that the C<-modifier> goes
2290 B<INSIDE> the arrayref, as an extra first element. This will
2291 B<NOT> do what you think it might:
2293 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2295 Here is a quick list of equivalencies, since there is some overlap:
2298 status => {'!=', 'completed', 'not like', 'pending%' }
2299 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2302 status => {'=', ['assigned', 'in-progress']}
2303 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2304 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2308 =head2 Special operators: IN, BETWEEN, etc.
2310 You can also use the hashref format to compare a list of fields using the
2311 C<IN> comparison operator, by specifying the list as an arrayref:
2314 status => 'completed',
2315 reportid => { -in => [567, 2335, 2] }
2318 Which would generate:
2320 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2321 @bind = ('completed', '567', '2335', '2');
2323 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2326 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2327 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2328 'sqltrue' (by default: C<1=1>).
2330 In addition to the array you can supply a chunk of literal sql or
2331 literal sql with bind:
2334 customer => { -in => \[
2335 'SELECT cust_id FROM cust WHERE balance > ?',
2338 status => { -in => \'SELECT status_codes FROM states' },
2344 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2345 AND status IN ( SELECT status_codes FROM states )
2349 Finally, if the argument to C<-in> is not a reference, it will be
2350 treated as a single-element array.
2352 Another pair of operators is C<-between> and C<-not_between>,
2353 used with an arrayref of two values:
2357 completion_date => {
2358 -not_between => ['2002-10-01', '2003-02-06']
2364 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2366 Just like with C<-in> all plausible combinations of literal SQL
2370 start0 => { -between => [ 1, 2 ] },
2371 start1 => { -between => \["? AND ?", 1, 2] },
2372 start2 => { -between => \"lower(x) AND upper(y)" },
2373 start3 => { -between => [
2375 \["upper(?)", 'stuff' ],
2382 ( start0 BETWEEN ? AND ? )
2383 AND ( start1 BETWEEN ? AND ? )
2384 AND ( start2 BETWEEN lower(x) AND upper(y) )
2385 AND ( start3 BETWEEN lower(x) AND upper(?) )
2387 @bind = (1, 2, 1, 2, 'stuff');
2390 These are the two builtin "special operators"; but the
2391 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2393 =head2 Unary operators: bool
2395 If you wish to test against boolean columns or functions within your
2396 database you can use the C<-bool> and C<-not_bool> operators. For
2397 example to test the column C<is_user> being true and the column
2398 C<is_enabled> being false you would use:-
2402 -not_bool => 'is_enabled',
2407 WHERE is_user AND NOT is_enabled
2409 If a more complex combination is required, testing more conditions,
2410 then you should use the and/or operators:-
2415 -not_bool => { two=> { -rlike => 'bar' } },
2416 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2427 (NOT ( three = ? OR three > ? ))
2430 =head2 Nested conditions, -and/-or prefixes
2432 So far, we've seen how multiple conditions are joined with a top-level
2433 C<AND>. We can change this by putting the different conditions we want in
2434 hashes and then putting those hashes in an array. For example:
2439 status => { -like => ['pending%', 'dispatched'] },
2443 status => 'unassigned',
2447 This data structure would create the following:
2449 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2450 OR ( user = ? AND status = ? ) )";
2451 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2454 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2455 to change the logic inside:
2461 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2462 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2469 $stmt = "WHERE ( user = ?
2470 AND ( ( workhrs > ? AND geo = ? )
2471 OR ( workhrs < ? OR geo = ? ) ) )";
2472 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2474 =head3 Algebraic inconsistency, for historical reasons
2476 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2477 operator goes C<outside> of the nested structure; whereas when connecting
2478 several constraints on one column, the C<-and> operator goes
2479 C<inside> the arrayref. Here is an example combining both features:
2482 -and => [a => 1, b => 2],
2483 -or => [c => 3, d => 4],
2484 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2489 WHERE ( ( ( a = ? AND b = ? )
2490 OR ( c = ? OR d = ? )
2491 OR ( e LIKE ? AND e LIKE ? ) ) )
2493 This difference in syntax is unfortunate but must be preserved for
2494 historical reasons. So be careful: the two examples below would
2495 seem algebraically equivalent, but they are not
2498 { -like => 'foo%' },
2499 { -like => '%bar' },
2501 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2504 { col => { -like => 'foo%' } },
2505 { col => { -like => '%bar' } },
2507 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2510 =head2 Literal SQL and value type operators
2512 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2513 side" is a column name and the "right side" is a value (normally rendered as
2514 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2515 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2516 alter this behavior. There are several ways of doing so.
2520 This is a virtual operator that signals the string to its right side is an
2521 identifier (a column name) and not a value. For example to compare two
2522 columns you would write:
2525 priority => { '<', 2 },
2526 requestor => { -ident => 'submitter' },
2531 $stmt = "WHERE priority < ? AND requestor = submitter";
2534 If you are maintaining legacy code you may see a different construct as
2535 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2540 This is a virtual operator that signals that the construct to its right side
2541 is a value to be passed to DBI. This is for example necessary when you want
2542 to write a where clause against an array (for RDBMS that support such
2543 datatypes). For example:
2546 array => { -value => [1, 2, 3] }
2551 $stmt = 'WHERE array = ?';
2552 @bind = ([1, 2, 3]);
2554 Note that if you were to simply say:
2560 the result would probably not be what you wanted:
2562 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2567 Finally, sometimes only literal SQL will do. To include a random snippet
2568 of SQL verbatim, you specify it as a scalar reference. Consider this only
2569 as a last resort. Usually there is a better way. For example:
2572 priority => { '<', 2 },
2573 requestor => { -in => \'(SELECT name FROM hitmen)' },
2578 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2581 Note that in this example, you only get one bind parameter back, since
2582 the verbatim SQL is passed as part of the statement.
2586 Never use untrusted input as a literal SQL argument - this is a massive
2587 security risk (there is no way to check literal snippets for SQL
2588 injections and other nastyness). If you need to deal with untrusted input
2589 use literal SQL with placeholders as described next.
2591 =head3 Literal SQL with placeholders and bind values (subqueries)
2593 If the literal SQL to be inserted has placeholders and bind values,
2594 use a reference to an arrayref (yes this is a double reference --
2595 not so common, but perfectly legal Perl). For example, to find a date
2596 in Postgres you can use something like this:
2599 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2604 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2607 Note that you must pass the bind values in the same format as they are returned
2608 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2609 to C<columns>, you must provide the bind values in the
2610 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2611 scalar value; most commonly the column name, but you can use any scalar value
2612 (including references and blessed references), L<SQL::Abstract> will simply
2613 pass it through intact. So if C<bindtype> is set to C<columns> the above
2614 example will look like:
2617 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2620 Literal SQL is especially useful for nesting parenthesized clauses in the
2621 main SQL query. Here is a first example:
2623 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2627 bar => \["IN ($sub_stmt)" => @sub_bind],
2632 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2633 WHERE c2 < ? AND c3 LIKE ?))";
2634 @bind = (1234, 100, "foo%");
2636 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2637 are expressed in the same way. Of course the C<$sub_stmt> and
2638 its associated bind values can be generated through a former call
2641 my ($sub_stmt, @sub_bind)
2642 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2643 c3 => {-like => "foo%"}});
2646 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2649 In the examples above, the subquery was used as an operator on a column;
2650 but the same principle also applies for a clause within the main C<%where>
2651 hash, like an EXISTS subquery:
2653 my ($sub_stmt, @sub_bind)
2654 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2655 my %where = ( -and => [
2657 \["EXISTS ($sub_stmt)" => @sub_bind],
2662 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2663 WHERE c1 = ? AND c2 > t0.c0))";
2667 Observe that the condition on C<c2> in the subquery refers to
2668 column C<t0.c0> of the main query: this is I<not> a bind
2669 value, so we have to express it through a scalar ref.
2670 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2671 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2672 what we wanted here.
2674 Finally, here is an example where a subquery is used
2675 for expressing unary negation:
2677 my ($sub_stmt, @sub_bind)
2678 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2679 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2681 lname => {like => '%son%'},
2682 \["NOT ($sub_stmt)" => @sub_bind],
2687 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2688 @bind = ('%son%', 10, 20)
2690 =head3 Deprecated usage of Literal SQL
2692 Below are some examples of archaic use of literal SQL. It is shown only as
2693 reference for those who deal with legacy code. Each example has a much
2694 better, cleaner and safer alternative that users should opt for in new code.
2700 my %where = ( requestor => \'IS NOT NULL' )
2702 $stmt = "WHERE requestor IS NOT NULL"
2704 This used to be the way of generating NULL comparisons, before the handling
2705 of C<undef> got formalized. For new code please use the superior syntax as
2706 described in L</Tests for NULL values>.
2710 my %where = ( requestor => \'= submitter' )
2712 $stmt = "WHERE requestor = submitter"
2714 This used to be the only way to compare columns. Use the superior L</-ident>
2715 method for all new code. For example an identifier declared in such a way
2716 will be properly quoted if L</quote_char> is properly set, while the legacy
2717 form will remain as supplied.
2721 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2723 $stmt = "WHERE completed > ? AND is_ready"
2724 @bind = ('2012-12-21')
2726 Using an empty string literal used to be the only way to express a boolean.
2727 For all new code please use the much more readable
2728 L<-bool|/Unary operators: bool> operator.
2734 These pages could go on for a while, since the nesting of the data
2735 structures this module can handle are pretty much unlimited (the
2736 module implements the C<WHERE> expansion as a recursive function
2737 internally). Your best bet is to "play around" with the module a
2738 little to see how the data structures behave, and choose the best
2739 format for your data based on that.
2741 And of course, all the values above will probably be replaced with
2742 variables gotten from forms or the command line. After all, if you
2743 knew everything ahead of time, you wouldn't have to worry about
2744 dynamically-generating SQL and could just hardwire it into your
2747 =head1 ORDER BY CLAUSES
2749 Some functions take an order by clause. This can either be a scalar (just a
2750 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2751 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2754 Given | Will Generate
2755 ---------------------------------------------------------------
2757 'colA' | ORDER BY colA
2759 [qw/colA colB/] | ORDER BY colA, colB
2761 {-asc => 'colA'} | ORDER BY colA ASC
2763 {-desc => 'colB'} | ORDER BY colB DESC
2765 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2767 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2769 \'colA DESC' | ORDER BY colA DESC
2771 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2772 | /* ...with $x bound to ? */
2775 { -asc => 'colA' }, | colA ASC,
2776 { -desc => [qw/colB/] }, | colB DESC,
2777 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2778 \'colE DESC', | colE DESC,
2779 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2780 ] | /* ...with $x bound to ? */
2781 ===============================================================
2785 =head1 SPECIAL OPERATORS
2787 my $sqlmaker = SQL::Abstract->new(special_ops => [
2791 my ($self, $field, $op, $arg) = @_;
2797 handler => 'method_name',
2801 A "special operator" is a SQL syntactic clause that can be
2802 applied to a field, instead of a usual binary operator.
2805 WHERE field IN (?, ?, ?)
2806 WHERE field BETWEEN ? AND ?
2807 WHERE MATCH(field) AGAINST (?, ?)
2809 Special operators IN and BETWEEN are fairly standard and therefore
2810 are builtin within C<SQL::Abstract> (as the overridable methods
2811 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2812 like the MATCH .. AGAINST example above which is specific to MySQL,
2813 you can write your own operator handlers - supply a C<special_ops>
2814 argument to the C<new> method. That argument takes an arrayref of
2815 operator definitions; each operator definition is a hashref with two
2822 the regular expression to match the operator
2826 Either a coderef or a plain scalar method name. In both cases
2827 the expected return is C<< ($sql, @bind) >>.
2829 When supplied with a method name, it is simply called on the
2830 L<SQL::Abstract> object as:
2832 $self->$method_name($field, $op, $arg)
2836 $field is the LHS of the operator
2837 $op is the part that matched the handler regex
2840 When supplied with a coderef, it is called as:
2842 $coderef->($self, $field, $op, $arg)
2847 For example, here is an implementation
2848 of the MATCH .. AGAINST syntax for MySQL
2850 my $sqlmaker = SQL::Abstract->new(special_ops => [
2852 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2853 {regex => qr/^match$/i,
2855 my ($self, $field, $op, $arg) = @_;
2856 $arg = [$arg] if not ref $arg;
2857 my $label = $self->_quote($field);
2858 my ($placeholder) = $self->_convert('?');
2859 my $placeholders = join ", ", (($placeholder) x @$arg);
2860 my $sql = $self->_sqlcase('match') . " ($label) "
2861 . $self->_sqlcase('against') . " ($placeholders) ";
2862 my @bind = $self->_bindtype($field, @$arg);
2863 return ($sql, @bind);
2870 =head1 UNARY OPERATORS
2872 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2876 my ($self, $op, $arg) = @_;
2882 handler => 'method_name',
2886 A "unary operator" is a SQL syntactic clause that can be
2887 applied to a field - the operator goes before the field
2889 You can write your own operator handlers - supply a C<unary_ops>
2890 argument to the C<new> method. That argument takes an arrayref of
2891 operator definitions; each operator definition is a hashref with two
2898 the regular expression to match the operator
2902 Either a coderef or a plain scalar method name. In both cases
2903 the expected return is C<< $sql >>.
2905 When supplied with a method name, it is simply called on the
2906 L<SQL::Abstract> object as:
2908 $self->$method_name($op, $arg)
2912 $op is the part that matched the handler regex
2913 $arg is the RHS or argument of the operator
2915 When supplied with a coderef, it is called as:
2917 $coderef->($self, $op, $arg)
2925 Thanks to some benchmarking by Mark Stosberg, it turns out that
2926 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2927 I must admit this wasn't an intentional design issue, but it's a
2928 byproduct of the fact that you get to control your C<DBI> handles
2931 To maximize performance, use a code snippet like the following:
2933 # prepare a statement handle using the first row
2934 # and then reuse it for the rest of the rows
2936 for my $href (@array_of_hashrefs) {
2937 $stmt ||= $sql->insert('table', $href);
2938 $sth ||= $dbh->prepare($stmt);
2939 $sth->execute($sql->values($href));
2942 The reason this works is because the keys in your C<$href> are sorted
2943 internally by B<SQL::Abstract>. Thus, as long as your data retains
2944 the same structure, you only have to generate the SQL the first time
2945 around. On subsequent queries, simply use the C<values> function provided
2946 by this module to return your values in the correct order.
2948 However this depends on the values having the same type - if, for
2949 example, the values of a where clause may either have values
2950 (resulting in sql of the form C<column = ?> with a single bind
2951 value), or alternatively the values might be C<undef> (resulting in
2952 sql of the form C<column IS NULL> with no bind value) then the
2953 caching technique suggested will not work.
2957 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2958 really like this part (I do, at least). Building up a complex query
2959 can be as simple as the following:
2966 use CGI::FormBuilder;
2969 my $form = CGI::FormBuilder->new(...);
2970 my $sql = SQL::Abstract->new;
2972 if ($form->submitted) {
2973 my $field = $form->field;
2974 my $id = delete $field->{id};
2975 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2978 Of course, you would still have to connect using C<DBI> to run the
2979 query, but the point is that if you make your form look like your
2980 table, the actual query script can be extremely simplistic.
2982 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2983 a fast interface to returning and formatting data. I frequently
2984 use these three modules together to write complex database query
2985 apps in under 50 lines.
2987 =head1 HOW TO CONTRIBUTE
2989 Contributions are always welcome, in all usable forms (we especially
2990 welcome documentation improvements). The delivery methods include git-
2991 or unified-diff formatted patches, GitHub pull requests, or plain bug
2992 reports either via RT or the Mailing list. Contributors are generally
2993 granted full access to the official repository after their first several
2994 patches pass successful review.
2996 This project is maintained in a git repository. The code and related tools are
2997 accessible at the following locations:
3001 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3003 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3005 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3007 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3013 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3014 Great care has been taken to preserve the I<published> behavior
3015 documented in previous versions in the 1.* family; however,
3016 some features that were previously undocumented, or behaved
3017 differently from the documentation, had to be changed in order
3018 to clarify the semantics. Hence, client code that was relying
3019 on some dark areas of C<SQL::Abstract> v1.*
3020 B<might behave differently> in v1.50.
3022 The main changes are:
3028 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3032 support for the { operator => \"..." } construct (to embed literal SQL)
3036 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3040 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3044 defensive programming: check arguments
3048 fixed bug with global logic, which was previously implemented
3049 through global variables yielding side-effects. Prior versions would
3050 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3051 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3052 Now this is interpreted
3053 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3058 fixed semantics of _bindtype on array args
3062 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3063 we just avoid shifting arrays within that tree.
3067 dropped the C<_modlogic> function
3071 =head1 ACKNOWLEDGEMENTS
3073 There are a number of individuals that have really helped out with
3074 this module. Unfortunately, most of them submitted bugs via CPAN
3075 so I have no idea who they are! But the people I do know are:
3077 Ash Berlin (order_by hash term support)
3078 Matt Trout (DBIx::Class support)
3079 Mark Stosberg (benchmarking)
3080 Chas Owens (initial "IN" operator support)
3081 Philip Collins (per-field SQL functions)
3082 Eric Kolve (hashref "AND" support)
3083 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3084 Dan Kubb (support for "quote_char" and "name_sep")
3085 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3086 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3087 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3088 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3089 Oliver Charles (support for "RETURNING" after "INSERT")
3095 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3099 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3101 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3103 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3104 While not an official support venue, C<DBIx::Class> makes heavy use of
3105 C<SQL::Abstract>, and as such list members there are very familiar with
3106 how to create queries.
3110 This module is free software; you may copy this under the same
3111 terms as perl itself (either the GNU General Public License or
3112 the Artistic License)