1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
188 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
192 $opt{expand_unary} = {};
195 -ident => '_expand_ident',
196 -value => '_expand_value',
197 -not => sub { +{ -op => [ 'not', $_[0]->_expand_expr($_[2]) ] } },
199 my ($self, undef, $v) = @_;
201 return $self->_expand_expr($v);
203 puke "-bool => undef not supported" unless defined($v);
204 return $self->_expand_ident(-ident => $v);
208 return bless \%opt, $class;
211 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
212 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
214 sub _assert_pass_injection_guard {
215 if ($_[1] =~ $_[0]->{injection_guard}) {
216 my $class = ref $_[0];
217 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
218 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
219 . "{injection_guard} attribute to ${class}->new()"
224 #======================================================================
226 #======================================================================
230 my $table = $self->_table(shift);
231 my $data = shift || return;
234 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
235 my ($sql, @bind) = $self->$method($data);
236 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
238 if ($options->{returning}) {
239 my ($s, @b) = $self->_insert_returning($options);
244 return wantarray ? ($sql, @bind) : $sql;
247 # So that subclasses can override INSERT ... RETURNING separately from
248 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
249 sub _insert_returning { shift->_returning(@_) }
252 my ($self, $options) = @_;
254 my $f = $options->{returning};
256 my ($sql, @bind) = $self->render_aqt(
257 $self->_expand_maybe_list_expr($f, undef, -ident)
260 ? $self->_sqlcase(' returning ') . $sql
261 : ($self->_sqlcase(' returning ').$sql, @bind);
264 sub _insert_HASHREF { # explicit list of fields and then values
265 my ($self, $data) = @_;
267 my @fields = sort keys %$data;
269 my ($sql, @bind) = $self->_insert_values($data);
272 $_ = $self->_quote($_) foreach @fields;
273 $sql = "( ".join(", ", @fields).") ".$sql;
275 return ($sql, @bind);
278 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
279 my ($self, $data) = @_;
281 # no names (arrayref) so can't generate bindtype
282 $self->{bindtype} ne 'columns'
283 or belch "can't do 'columns' bindtype when called with arrayref";
285 my (@values, @all_bind);
286 foreach my $value (@$data) {
287 my ($values, @bind) = $self->_insert_value(undef, $value);
288 push @values, $values;
289 push @all_bind, @bind;
291 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
292 return ($sql, @all_bind);
295 sub _insert_ARRAYREFREF { # literal SQL with bind
296 my ($self, $data) = @_;
298 my ($sql, @bind) = @${$data};
299 $self->_assert_bindval_matches_bindtype(@bind);
301 return ($sql, @bind);
305 sub _insert_SCALARREF { # literal SQL without bind
306 my ($self, $data) = @_;
312 my ($self, $data) = @_;
314 my (@values, @all_bind);
315 foreach my $column (sort keys %$data) {
316 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
317 push @values, $values;
318 push @all_bind, @bind;
320 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
321 return ($sql, @all_bind);
325 my ($self, $column, $v) = @_;
327 return $self->render_aqt(
328 $self->_expand_insert_value($column, $v)
332 sub _expand_insert_value {
333 my ($self, $column, $v) = @_;
335 if (ref($v) eq 'ARRAY') {
336 if ($self->{array_datatypes}) {
337 return +{ -bind => [ $column, $v ] };
339 my ($sql, @bind) = @$v;
340 $self->_assert_bindval_matches_bindtype(@bind);
341 return +{ -literal => $v };
343 if (ref($v) eq 'HASH') {
344 if (grep !/^-/, keys %$v) {
345 belch "HASH ref as bind value in insert is not supported";
346 return +{ -bind => [ $column, $v ] };
350 return +{ -bind => [ $column, undef ] };
352 local our $Cur_Col_Meta = $column;
353 return $self->expand_expr($v);
358 #======================================================================
360 #======================================================================
365 my $table = $self->_table(shift);
366 my $data = shift || return;
370 # first build the 'SET' part of the sql statement
371 puke "Unsupported data type specified to \$sql->update"
372 unless ref $data eq 'HASH';
374 my ($sql, @all_bind) = $self->_update_set_values($data);
375 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
379 my($where_sql, @where_bind) = $self->where($where);
381 push @all_bind, @where_bind;
384 if ($options->{returning}) {
385 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
386 $sql .= $returning_sql;
387 push @all_bind, @returning_bind;
390 return wantarray ? ($sql, @all_bind) : $sql;
393 sub _update_set_values {
394 my ($self, $data) = @_;
396 return $self->render_aqt(
397 $self->_expand_update_set_values($data),
401 sub _expand_update_set_values {
402 my ($self, $data) = @_;
403 $self->_expand_maybe_list_expr( [
406 $set = { -bind => $_ } unless defined $set;
407 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
413 ? ($self->{array_datatypes}
414 ? [ $k, +{ -bind => [ $k, $v ] } ]
415 : [ $k, +{ -literal => $v } ])
417 local our $Cur_Col_Meta = $k;
418 [ $k, $self->_expand_expr($v) ]
425 # So that subclasses can override UPDATE ... RETURNING separately from
427 sub _update_returning { shift->_returning(@_) }
431 #======================================================================
433 #======================================================================
438 my $table = $self->_table(shift);
439 my $fields = shift || '*';
443 my ($fields_sql, @bind) = $self->_select_fields($fields);
445 my ($where_sql, @where_bind) = $self->where($where, $order);
446 push @bind, @where_bind;
448 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
449 $self->_sqlcase('from'), $table)
452 return wantarray ? ($sql, @bind) : $sql;
456 my ($self, $fields) = @_;
457 return $fields unless ref($fields);
458 return $self->render_aqt(
459 $self->_expand_maybe_list_expr($fields, undef, '-ident')
463 #======================================================================
465 #======================================================================
470 my $table = $self->_table(shift);
474 my($where_sql, @bind) = $self->where($where);
475 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
477 if ($options->{returning}) {
478 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
479 $sql .= $returning_sql;
480 push @bind, @returning_bind;
483 return wantarray ? ($sql, @bind) : $sql;
486 # So that subclasses can override DELETE ... RETURNING separately from
488 sub _delete_returning { shift->_returning(@_) }
492 #======================================================================
494 #======================================================================
498 # Finally, a separate routine just to handle WHERE clauses
500 my ($self, $where, $order) = @_;
502 local $self->{convert_where} = $self->{convert};
505 my ($sql, @bind) = defined($where)
506 ? $self->_recurse_where($where)
508 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
512 my ($order_sql, @order_bind) = $self->_order_by($order);
514 push @bind, @order_bind;
517 return wantarray ? ($sql, @bind) : $sql;
521 my ($self, $expr, $default_scalar_to) = @_;
522 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
523 $self->_expand_expr($expr);
527 my ($self, $aqt) = @_;
528 my ($k, $v, @rest) = %$aqt;
530 if (my $meth = $self->{render}{$k}) {
531 return $self->$meth($v);
533 die "notreached: $k";
537 my ($self, $expr) = @_;
538 $self->render_aqt($self->expand_expr($expr));
542 my ($self, $expr, $logic) = @_;
543 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
544 return undef unless defined($expr);
545 if (ref($expr) eq 'HASH') {
546 return undef unless my $kc = keys %$expr;
551 map $self->_expand_expr({ $_ => $expr->{$_} }, $logic),
555 my ($key, $value) = %$expr;
556 if (my $exp = $self->{expand}{$key}) {
557 return $self->$exp($key, $value);
559 return $self->_expand_expr_hashpair($key, $value, $logic);
561 if (ref($expr) eq 'ARRAY') {
562 my $logic = lc($logic || $self->{logic});
563 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
566 (ref($_) eq 'ARRAY' and @$_)
567 or (ref($_) eq 'HASH' and %$_)
573 while (my ($el) = splice @expr, 0, 1) {
574 puke "Supplying an empty left hand side argument is not supported in array-pairs"
575 unless defined($el) and length($el);
576 my $elref = ref($el);
578 local $Expand_Depth = 0;
579 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
580 } elsif ($elref eq 'ARRAY') {
581 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
582 } elsif (my $l = is_literal_value($el)) {
583 push @res, { -literal => $l };
584 } elsif ($elref eq 'HASH') {
585 local $Expand_Depth = 0;
586 push @res, grep defined, $self->_expand_expr($el) if %$el;
592 # return $res[0] if @res == 1;
593 return { -op => [ $logic, @res ] };
595 if (my $literal = is_literal_value($expr)) {
596 return +{ -literal => $literal };
598 if (!ref($expr) or Scalar::Util::blessed($expr)) {
599 if (my $d = our $Default_Scalar_To) {
600 return $self->_expand_expr({ $d => $expr });
602 if (my $m = our $Cur_Col_Meta) {
603 return +{ -bind => [ $m, $expr ] };
605 return +{ -bind => [ undef, $expr ] };
610 sub _expand_expr_hashpair {
611 my ($self, $k, $v, $logic) = @_;
612 unless (defined($k) and length($k)) {
613 if (defined($k) and my $literal = is_literal_value($v)) {
614 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
615 return { -literal => $literal };
617 puke "Supplying an empty left hand side argument is not supported";
620 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
621 if ($k =~ s/ [_\s]? \d+ $//x ) {
622 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
623 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
626 # DBIx::Class requires a nest warning to be emitted once but the private
627 # method it overrode to do so no longer exists
628 if ($self->{is_dbic_sqlmaker}) {
629 unless (our $Nest_Warned) {
631 "-nest in search conditions is deprecated, you most probably wanted:\n"
632 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
637 return $self->_expand_expr($v);
639 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
642 $self->_expand_expr({ "-${rest}", $v }, $logic)
645 if (my ($logic) = $k =~ /^-(and|or)$/i) {
646 if (ref($v) eq 'HASH') {
647 return $self->_expand_expr($v, $logic);
649 if (ref($v) eq 'ARRAY') {
650 return $self->_expand_expr($v, $logic);
655 $op =~ s/^-// if length($op) > 1;
657 # top level special ops are illegal in general
658 # note that, arguably, if it makes no sense at top level, it also
659 # makes no sense on the other side of an = sign or similar but DBIC
660 # gets disappointingly upset if I disallow it
662 (our $Expand_Depth) == 1
663 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
665 puke "Illegal use of top-level '-$op'"
667 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
668 return { -op => [ $op, $v ] };
671 if (my $custom = $self->{expand_unary}{$k}) {
672 return $self->$custom($v);
674 if ($self->{render}{$k}) {
680 and (keys %$v)[0] =~ /^-/
682 my ($func) = $k =~ /^-(.*)$/;
683 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
684 return +{ -op => [ $func, $self->_expand_expr($v) ] };
686 return +{ -func => [ $func, $self->_expand_expr($v) ] };
688 if (!ref($v) or is_literal_value($v)) {
689 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
696 and exists $v->{-value}
697 and not defined $v->{-value}
700 return $self->_expand_expr({ $k => { $self->{cmp} => undef } });
702 if (!ref($v) or Scalar::Util::blessed($v)) {
703 my $d = our $Default_Scalar_To;
707 $self->_expand_ident(-ident => $k),
709 ? $self->_expand_expr($d => $v)
710 : { -bind => [ $k, $v ] }
715 if (ref($v) eq 'HASH') {
719 map $self->_expand_expr({ $k => { $_ => $v->{$_} } }),
723 return undef unless keys %$v;
725 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
726 $self->_assert_pass_injection_guard($op);
727 if ($op =~ s/ [_\s]? \d+ $//x ) {
728 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
729 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
731 if ($op =~ /^(?:not )?between$/) {
732 local our $Cur_Col_Meta = $k;
733 my @rhs = map $self->_expand_expr($_),
734 ref($vv) eq 'ARRAY' ? @$vv : $vv;
736 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
738 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
740 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
744 $self->_expand_ident(-ident => $k),
748 if ($op =~ /^(?:not )?in$/) {
749 if (my $literal = is_literal_value($vv)) {
750 my ($sql, @bind) = @$literal;
751 my $opened_sql = $self->_open_outer_paren($sql);
753 $op, $self->_expand_ident(-ident => $k),
754 [ { -literal => [ $opened_sql, @bind ] } ]
758 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
759 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
760 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
761 . 'will emit the logically correct SQL instead of raising this exception)'
763 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
765 my @rhs = map $self->_expand_expr($_),
766 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
767 map { defined($_) ? $_: puke($undef_err) }
768 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
769 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
773 $self->_expand_ident(-ident => $k),
777 if ($op eq 'ident') {
778 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
779 puke "-$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
783 $self->_expand_ident(-ident => $k),
784 $self->_expand_ident(-ident => $vv),
787 if ($op eq 'value') {
788 return $self->_expand_expr({ $k, undef }) unless defined($vv);
791 $self->_expand_ident(-ident => $k),
792 { -bind => [ $k, $vv ] }
795 if ($op =~ /^is(?: not)?$/) {
796 puke "$op can only take undef as argument"
800 and exists($vv->{-value})
801 and !defined($vv->{-value})
803 return +{ -op => [ $op.' null', $self->_expand_ident(-ident => $k) ] };
805 if ($op =~ /^(and|or)$/) {
806 if (ref($vv) eq 'HASH') {
809 map $self->_expand_expr({ $k, { $_ => $vv->{$_} } }),
814 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
815 return { -op => [ $op, $self->_expand_ident(-ident => $k), $vv ] };
817 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
820 $self->_expand_ident(-ident => $k),
821 { -op => [ $op, $vv ] }
824 if (ref($vv) eq 'ARRAY') {
825 my ($logic, @values) = (
826 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
831 $op =~ $self->{inequality_op}
832 or $op =~ $self->{not_like_op}
834 if (lc($logic) eq '-or' and @values > 1) {
835 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
836 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
837 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
842 # try to DWIM on equality operators
844 $op =~ $self->{equality_op} ? $self->sqlfalse
845 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
846 : $op =~ $self->{inequality_op} ? $self->sqltrue
847 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
848 : puke "operator '$op' applied on an empty array (field '$k')";
852 map $self->_expand_expr({ $k => { $vk => $_ } }),
860 and exists $vv->{-value}
861 and not defined $vv->{-value}
865 $op =~ /^not$/i ? 'is not' # legacy
866 : $op =~ $self->{equality_op} ? 'is'
867 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
868 : $op =~ $self->{inequality_op} ? 'is not'
869 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
870 : puke "unexpected operator '$op' with undef operand";
871 return +{ -op => [ $is.' null', $self->_expand_ident(-ident => $k) ] };
873 local our $Cur_Col_Meta = $k;
876 $self->_expand_ident(-ident => $k),
877 $self->_expand_expr($vv)
880 if (ref($v) eq 'ARRAY') {
881 return $self->sqlfalse unless @$v;
882 $self->_debug("ARRAY($k) means distribute over elements");
884 $v->[0] =~ /^-((?:and|or))$/i
885 ? ($v = [ @{$v}[1..$#$v] ], $1)
886 : ($self->{logic} || 'or')
890 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
893 if (my $literal = is_literal_value($v)) {
895 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
898 my ($sql, @bind) = @$literal;
899 if ($self->{bindtype} eq 'columns') {
901 $self->_assert_bindval_matches_bindtype($_);
904 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
910 my ($self, undef, $body) = @_;
911 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
912 ref($body) ? @$body : $body;
913 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
914 unless ($self->{quote_char}) {
915 $self->_assert_pass_injection_guard($_) for @parts;
917 return +{ -ident => \@parts };
921 +{ -bind => [ our $Cur_Col_Meta, $_[2] ] };
925 my ($self, $where, $logic) = @_;
927 # Special case: top level simple string treated as literal
929 my $where_exp = (ref($where)
930 ? $self->_expand_expr($where, $logic)
931 : { -literal => [ $where ] });
933 # dispatch expanded expression
935 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
936 # DBIx::Class used to call _recurse_where in scalar context
937 # something else might too...
939 return ($sql, @bind);
942 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
948 my ($self, $ident) = @_;
950 return $self->_convert($self->_quote($ident));
953 my %unop_postfix = map +($_ => 1),
954 'is null', 'is not null',
962 my ($self, $args) = @_;
963 my ($left, $low, $high) = @$args;
964 my ($rhsql, @rhbind) = do {
966 puke "Single arg to between must be a literal"
967 unless $low->{-literal};
970 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
971 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
972 @{$l}[1..$#$l], @{$h}[1..$#$h])
975 my ($lhsql, @lhbind) = $self->render_aqt($left);
977 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
981 }), 'between', 'not between'),
985 my ($self, $args) = @_;
986 my ($lhs, $rhs) = @$args;
989 my ($sql, @bind) = $self->render_aqt($_);
990 push @in_bind, @bind;
993 my ($lhsql, @lbind) = $self->render_aqt($lhs);
995 $lhsql.' '.$self->_sqlcase($op).' ( '
1001 }), 'in', 'not in'),
1005 my ($self, $v) = @_;
1006 my ($op, @args) = @$v;
1007 $op =~ s/^-// if length($op) > 1;
1009 if (my $h = $special{$op}) {
1010 return $self->$h(\@args);
1012 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1013 if ($us and @args > 1) {
1014 puke "Special op '${op}' requires first value to be identifier"
1015 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1016 my $k = join(($self->{name_sep}||'.'), @$ident);
1017 local our $Expand_Depth = 1;
1018 return $self->${\($us->{handler})}($k, $op, $args[1]);
1020 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1021 return $self->${\($us->{handler})}($op, $args[0]);
1023 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1024 if (@args == 1 and $op !~ /^(and|or)$/) {
1025 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1026 my $op_sql = $self->_sqlcase($final_op);
1028 $unop_postfix{lc($final_op)}
1029 ? "${expr_sql} ${op_sql}"
1030 : "${op_sql} ${expr_sql}"
1032 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1034 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1035 return '' unless @parts;
1036 my $is_andor = !!($op =~ /^(and|or)$/);
1037 return @{$parts[0]} if $is_andor and @parts == 1;
1038 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1039 ' '.$self->_sqlcase($final_op).' ',
1044 map @{$_}[1..$#$_], @parts
1051 my ($self, $list) = @_;
1052 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
1053 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1057 my ($self, $rest) = @_;
1058 my ($func, @args) = @$rest;
1062 push @arg_sql, shift @x;
1064 } map [ $self->render_aqt($_) ], @args;
1065 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1069 my ($self, $bind) = @_;
1070 return ($self->_convert('?'), $self->_bindtype(@$bind));
1073 sub _render_literal {
1074 my ($self, $literal) = @_;
1075 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1079 # Some databases (SQLite) treat col IN (1, 2) different from
1080 # col IN ( (1, 2) ). Use this to strip all outer parens while
1081 # adding them back in the corresponding method
1082 sub _open_outer_paren {
1083 my ($self, $sql) = @_;
1085 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1087 # there are closing parens inside, need the heavy duty machinery
1088 # to reevaluate the extraction starting from $sql (full reevaluation)
1089 if ($inner =~ /\)/) {
1090 require Text::Balanced;
1092 my (undef, $remainder) = do {
1093 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1095 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1098 # the entire expression needs to be a balanced bracketed thing
1099 # (after an extract no remainder sans trailing space)
1100 last if defined $remainder and $remainder =~ /\S/;
1110 #======================================================================
1112 #======================================================================
1114 sub _expand_order_by {
1115 my ($self, $arg) = @_;
1117 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1119 my $expander = sub {
1120 my ($self, $dir, $expr) = @_;
1121 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1122 foreach my $arg (@to_expand) {
1126 and grep /^-(asc|desc)$/, keys %$arg
1128 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1131 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1132 map $self->expand_expr($_, -ident),
1133 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1134 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1137 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1138 sub { shift->$expander(asc => @_) },
1139 sub { shift->$expander(desc => @_) },
1142 return $self->$expander(undef, $arg);
1146 my ($self, $arg) = @_;
1148 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1150 my ($sql, @bind) = $self->render_aqt($expanded);
1152 return '' unless length($sql);
1154 my $final_sql = $self->_sqlcase(' order by ').$sql;
1156 return wantarray ? ($final_sql, @bind) : $final_sql;
1159 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1161 sub _order_by_chunks {
1162 my ($self, $arg) = @_;
1164 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1166 return $self->_chunkify_order_by($expanded);
1169 sub _chunkify_order_by {
1170 my ($self, $expanded) = @_;
1172 return grep length, $self->render_aqt($expanded)
1173 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1176 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1177 return map $self->_chunkify_order_by($_), @$l;
1179 return [ $self->render_aqt($_) ];
1183 #======================================================================
1184 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1185 #======================================================================
1191 $self->_expand_maybe_list_expr($from, undef, -ident)
1196 #======================================================================
1198 #======================================================================
1200 sub _expand_maybe_list_expr {
1201 my ($self, $expr, $logic, $default) = @_;
1203 if (ref($expr) eq 'ARRAY') {
1205 map $self->expand_expr($_, $default), @$expr
1212 return $self->expand_expr($e, $default);
1215 # highly optimized, as it's called way too often
1217 # my ($self, $label) = @_;
1219 return '' unless defined $_[1];
1220 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1221 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1223 unless ($_[0]->{quote_char}) {
1224 if (ref($_[1]) eq 'ARRAY') {
1225 return join($_[0]->{name_sep}||'.', @{$_[1]});
1227 $_[0]->_assert_pass_injection_guard($_[1]);
1232 my $qref = ref $_[0]->{quote_char};
1234 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1235 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1236 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1238 my $esc = $_[0]->{escape_char} || $r;
1240 # parts containing * are naturally unquoted
1242 $_[0]->{name_sep}||'',
1246 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1248 (ref($_[1]) eq 'ARRAY'
1252 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1260 # Conversion, if applicable
1262 #my ($self, $arg) = @_;
1263 if ($_[0]->{convert_where}) {
1264 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1271 #my ($self, $col, @vals) = @_;
1272 # called often - tighten code
1273 return $_[0]->{bindtype} eq 'columns'
1274 ? map {[$_[1], $_]} @_[2 .. $#_]
1279 # Dies if any element of @bind is not in [colname => value] format
1280 # if bindtype is 'columns'.
1281 sub _assert_bindval_matches_bindtype {
1282 # my ($self, @bind) = @_;
1284 if ($self->{bindtype} eq 'columns') {
1286 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1287 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1293 sub _join_sql_clauses {
1294 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1296 if (@$clauses_aref > 1) {
1297 my $join = " " . $self->_sqlcase($logic) . " ";
1298 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1299 return ($sql, @$bind_aref);
1301 elsif (@$clauses_aref) {
1302 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1305 return (); # if no SQL, ignore @$bind_aref
1310 # Fix SQL case, if so requested
1312 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1313 # don't touch the argument ... crooked logic, but let's not change it!
1314 return $_[0]->{case} ? $_[1] : uc($_[1]);
1318 #======================================================================
1319 # DISPATCHING FROM REFKIND
1320 #======================================================================
1323 my ($self, $data) = @_;
1325 return 'UNDEF' unless defined $data;
1327 # blessed objects are treated like scalars
1328 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1330 return 'SCALAR' unless $ref;
1333 while ($ref eq 'REF') {
1335 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1339 return ($ref||'SCALAR') . ('REF' x $n_steps);
1343 my ($self, $data) = @_;
1344 my @try = ($self->_refkind($data));
1345 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1346 push @try, 'FALLBACK';
1350 sub _METHOD_FOR_refkind {
1351 my ($self, $meth_prefix, $data) = @_;
1354 for (@{$self->_try_refkind($data)}) {
1355 $method = $self->can($meth_prefix."_".$_)
1359 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1363 sub _SWITCH_refkind {
1364 my ($self, $data, $dispatch_table) = @_;
1367 for (@{$self->_try_refkind($data)}) {
1368 $coderef = $dispatch_table->{$_}
1372 puke "no dispatch entry for ".$self->_refkind($data)
1381 #======================================================================
1382 # VALUES, GENERATE, AUTOLOAD
1383 #======================================================================
1385 # LDNOTE: original code from nwiger, didn't touch code in that section
1386 # I feel the AUTOLOAD stuff should not be the default, it should
1387 # only be activated on explicit demand by user.
1391 my $data = shift || return;
1392 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1393 unless ref $data eq 'HASH';
1396 foreach my $k (sort keys %$data) {
1397 my $v = $data->{$k};
1398 $self->_SWITCH_refkind($v, {
1400 if ($self->{array_datatypes}) { # array datatype
1401 push @all_bind, $self->_bindtype($k, $v);
1403 else { # literal SQL with bind
1404 my ($sql, @bind) = @$v;
1405 $self->_assert_bindval_matches_bindtype(@bind);
1406 push @all_bind, @bind;
1409 ARRAYREFREF => sub { # literal SQL with bind
1410 my ($sql, @bind) = @${$v};
1411 $self->_assert_bindval_matches_bindtype(@bind);
1412 push @all_bind, @bind;
1414 SCALARREF => sub { # literal SQL without bind
1416 SCALAR_or_UNDEF => sub {
1417 push @all_bind, $self->_bindtype($k, $v);
1428 my(@sql, @sqlq, @sqlv);
1432 if ($ref eq 'HASH') {
1433 for my $k (sort keys %$_) {
1436 my $label = $self->_quote($k);
1437 if ($r eq 'ARRAY') {
1438 # literal SQL with bind
1439 my ($sql, @bind) = @$v;
1440 $self->_assert_bindval_matches_bindtype(@bind);
1441 push @sqlq, "$label = $sql";
1443 } elsif ($r eq 'SCALAR') {
1444 # literal SQL without bind
1445 push @sqlq, "$label = $$v";
1447 push @sqlq, "$label = ?";
1448 push @sqlv, $self->_bindtype($k, $v);
1451 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1452 } elsif ($ref eq 'ARRAY') {
1453 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1456 if ($r eq 'ARRAY') { # literal SQL with bind
1457 my ($sql, @bind) = @$v;
1458 $self->_assert_bindval_matches_bindtype(@bind);
1461 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1462 # embedded literal SQL
1469 push @sql, '(' . join(', ', @sqlq) . ')';
1470 } elsif ($ref eq 'SCALAR') {
1474 # strings get case twiddled
1475 push @sql, $self->_sqlcase($_);
1479 my $sql = join ' ', @sql;
1481 # this is pretty tricky
1482 # if ask for an array, return ($stmt, @bind)
1483 # otherwise, s/?/shift @sqlv/ to put it inline
1485 return ($sql, @sqlv);
1487 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1488 ref $d ? $d->[1] : $d/e;
1497 # This allows us to check for a local, then _form, attr
1499 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1500 return $self->generate($name, @_);
1511 SQL::Abstract - Generate SQL from Perl data structures
1517 my $sql = SQL::Abstract->new;
1519 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1521 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1523 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1525 my($stmt, @bind) = $sql->delete($table, \%where);
1527 # Then, use these in your DBI statements
1528 my $sth = $dbh->prepare($stmt);
1529 $sth->execute(@bind);
1531 # Just generate the WHERE clause
1532 my($stmt, @bind) = $sql->where(\%where, $order);
1534 # Return values in the same order, for hashed queries
1535 # See PERFORMANCE section for more details
1536 my @bind = $sql->values(\%fieldvals);
1540 This module was inspired by the excellent L<DBIx::Abstract>.
1541 However, in using that module I found that what I really wanted
1542 to do was generate SQL, but still retain complete control over my
1543 statement handles and use the DBI interface. So, I set out to
1544 create an abstract SQL generation module.
1546 While based on the concepts used by L<DBIx::Abstract>, there are
1547 several important differences, especially when it comes to WHERE
1548 clauses. I have modified the concepts used to make the SQL easier
1549 to generate from Perl data structures and, IMO, more intuitive.
1550 The underlying idea is for this module to do what you mean, based
1551 on the data structures you provide it. The big advantage is that
1552 you don't have to modify your code every time your data changes,
1553 as this module figures it out.
1555 To begin with, an SQL INSERT is as easy as just specifying a hash
1556 of C<key=value> pairs:
1559 name => 'Jimbo Bobson',
1560 phone => '123-456-7890',
1561 address => '42 Sister Lane',
1562 city => 'St. Louis',
1563 state => 'Louisiana',
1566 The SQL can then be generated with this:
1568 my($stmt, @bind) = $sql->insert('people', \%data);
1570 Which would give you something like this:
1572 $stmt = "INSERT INTO people
1573 (address, city, name, phone, state)
1574 VALUES (?, ?, ?, ?, ?)";
1575 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1576 '123-456-7890', 'Louisiana');
1578 These are then used directly in your DBI code:
1580 my $sth = $dbh->prepare($stmt);
1581 $sth->execute(@bind);
1583 =head2 Inserting and Updating Arrays
1585 If your database has array types (like for example Postgres),
1586 activate the special option C<< array_datatypes => 1 >>
1587 when creating the C<SQL::Abstract> object.
1588 Then you may use an arrayref to insert and update database array types:
1590 my $sql = SQL::Abstract->new(array_datatypes => 1);
1592 planets => [qw/Mercury Venus Earth Mars/]
1595 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1599 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1601 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1604 =head2 Inserting and Updating SQL
1606 In order to apply SQL functions to elements of your C<%data> you may
1607 specify a reference to an arrayref for the given hash value. For example,
1608 if you need to execute the Oracle C<to_date> function on a value, you can
1609 say something like this:
1613 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1616 The first value in the array is the actual SQL. Any other values are
1617 optional and would be included in the bind values array. This gives
1620 my($stmt, @bind) = $sql->insert('people', \%data);
1622 $stmt = "INSERT INTO people (name, date_entered)
1623 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1624 @bind = ('Bill', '03/02/2003');
1626 An UPDATE is just as easy, all you change is the name of the function:
1628 my($stmt, @bind) = $sql->update('people', \%data);
1630 Notice that your C<%data> isn't touched; the module will generate
1631 the appropriately quirky SQL for you automatically. Usually you'll
1632 want to specify a WHERE clause for your UPDATE, though, which is
1633 where handling C<%where> hashes comes in handy...
1635 =head2 Complex where statements
1637 This module can generate pretty complicated WHERE statements
1638 easily. For example, simple C<key=value> pairs are taken to mean
1639 equality, and if you want to see if a field is within a set
1640 of values, you can use an arrayref. Let's say we wanted to
1641 SELECT some data based on this criteria:
1644 requestor => 'inna',
1645 worker => ['nwiger', 'rcwe', 'sfz'],
1646 status => { '!=', 'completed' }
1649 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1651 The above would give you something like this:
1653 $stmt = "SELECT * FROM tickets WHERE
1654 ( requestor = ? ) AND ( status != ? )
1655 AND ( worker = ? OR worker = ? OR worker = ? )";
1656 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1658 Which you could then use in DBI code like so:
1660 my $sth = $dbh->prepare($stmt);
1661 $sth->execute(@bind);
1667 The methods are simple. There's one for every major SQL operation,
1668 and a constructor you use first. The arguments are specified in a
1669 similar order for each method (table, then fields, then a where
1670 clause) to try and simplify things.
1672 =head2 new(option => 'value')
1674 The C<new()> function takes a list of options and values, and returns
1675 a new B<SQL::Abstract> object which can then be used to generate SQL
1676 through the methods below. The options accepted are:
1682 If set to 'lower', then SQL will be generated in all lowercase. By
1683 default SQL is generated in "textbook" case meaning something like:
1685 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1687 Any setting other than 'lower' is ignored.
1691 This determines what the default comparison operator is. By default
1692 it is C<=>, meaning that a hash like this:
1694 %where = (name => 'nwiger', email => 'nate@wiger.org');
1696 Will generate SQL like this:
1698 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1700 However, you may want loose comparisons by default, so if you set
1701 C<cmp> to C<like> you would get SQL such as:
1703 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1705 You can also override the comparison on an individual basis - see
1706 the huge section on L</"WHERE CLAUSES"> at the bottom.
1708 =item sqltrue, sqlfalse
1710 Expressions for inserting boolean values within SQL statements.
1711 By default these are C<1=1> and C<1=0>. They are used
1712 by the special operators C<-in> and C<-not_in> for generating
1713 correct SQL even when the argument is an empty array (see below).
1717 This determines the default logical operator for multiple WHERE
1718 statements in arrays or hashes. If absent, the default logic is "or"
1719 for arrays, and "and" for hashes. This means that a WHERE
1723 event_date => {'>=', '2/13/99'},
1724 event_date => {'<=', '4/24/03'},
1727 will generate SQL like this:
1729 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1731 This is probably not what you want given this query, though (look
1732 at the dates). To change the "OR" to an "AND", simply specify:
1734 my $sql = SQL::Abstract->new(logic => 'and');
1736 Which will change the above C<WHERE> to:
1738 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1740 The logic can also be changed locally by inserting
1741 a modifier in front of an arrayref:
1743 @where = (-and => [event_date => {'>=', '2/13/99'},
1744 event_date => {'<=', '4/24/03'} ]);
1746 See the L</"WHERE CLAUSES"> section for explanations.
1750 This will automatically convert comparisons using the specified SQL
1751 function for both column and value. This is mostly used with an argument
1752 of C<upper> or C<lower>, so that the SQL will have the effect of
1753 case-insensitive "searches". For example, this:
1755 $sql = SQL::Abstract->new(convert => 'upper');
1756 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1758 Will turn out the following SQL:
1760 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1762 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1763 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1764 not validate this option; it will just pass through what you specify verbatim).
1768 This is a kludge because many databases suck. For example, you can't
1769 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1770 Instead, you have to use C<bind_param()>:
1772 $sth->bind_param(1, 'reg data');
1773 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1775 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1776 which loses track of which field each slot refers to. Fear not.
1778 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1779 Currently, you can specify either C<normal> (default) or C<columns>. If you
1780 specify C<columns>, you will get an array that looks like this:
1782 my $sql = SQL::Abstract->new(bindtype => 'columns');
1783 my($stmt, @bind) = $sql->insert(...);
1786 [ 'column1', 'value1' ],
1787 [ 'column2', 'value2' ],
1788 [ 'column3', 'value3' ],
1791 You can then iterate through this manually, using DBI's C<bind_param()>.
1793 $sth->prepare($stmt);
1796 my($col, $data) = @$_;
1797 if ($col eq 'details' || $col eq 'comments') {
1798 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1799 } elsif ($col eq 'image') {
1800 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1802 $sth->bind_param($i, $data);
1806 $sth->execute; # execute without @bind now
1808 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1809 Basically, the advantage is still that you don't have to care which fields
1810 are or are not included. You could wrap that above C<for> loop in a simple
1811 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1812 get a layer of abstraction over manual SQL specification.
1814 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1815 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1816 will expect the bind values in this format.
1820 This is the character that a table or column name will be quoted
1821 with. By default this is an empty string, but you could set it to
1822 the character C<`>, to generate SQL like this:
1824 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1826 Alternatively, you can supply an array ref of two items, the first being the left
1827 hand quote character, and the second the right hand quote character. For
1828 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1829 that generates SQL like this:
1831 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1833 Quoting is useful if you have tables or columns names that are reserved
1834 words in your database's SQL dialect.
1838 This is the character that will be used to escape L</quote_char>s appearing
1839 in an identifier before it has been quoted.
1841 The parameter default in case of a single L</quote_char> character is the quote
1844 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1845 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1846 of the B<opening (left)> L</quote_char> within the identifier are currently left
1847 untouched. The default for opening-closing-style quotes may change in future
1848 versions, thus you are B<strongly encouraged> to specify the escape character
1853 This is the character that separates a table and column name. It is
1854 necessary to specify this when the C<quote_char> option is selected,
1855 so that tables and column names can be individually quoted like this:
1857 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1859 =item injection_guard
1861 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1862 column name specified in a query structure. This is a safety mechanism to avoid
1863 injection attacks when mishandling user input e.g.:
1865 my %condition_as_column_value_pairs = get_values_from_user();
1866 $sqla->select( ... , \%condition_as_column_value_pairs );
1868 If the expression matches an exception is thrown. Note that literal SQL
1869 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1871 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1873 =item array_datatypes
1875 When this option is true, arrayrefs in INSERT or UPDATE are
1876 interpreted as array datatypes and are passed directly
1878 When this option is false, arrayrefs are interpreted
1879 as literal SQL, just like refs to arrayrefs
1880 (but this behavior is for backwards compatibility; when writing
1881 new queries, use the "reference to arrayref" syntax
1887 Takes a reference to a list of "special operators"
1888 to extend the syntax understood by L<SQL::Abstract>.
1889 See section L</"SPECIAL OPERATORS"> for details.
1893 Takes a reference to a list of "unary operators"
1894 to extend the syntax understood by L<SQL::Abstract>.
1895 See section L</"UNARY OPERATORS"> for details.
1901 =head2 insert($table, \@values || \%fieldvals, \%options)
1903 This is the simplest function. You simply give it a table name
1904 and either an arrayref of values or hashref of field/value pairs.
1905 It returns an SQL INSERT statement and a list of bind values.
1906 See the sections on L</"Inserting and Updating Arrays"> and
1907 L</"Inserting and Updating SQL"> for information on how to insert
1908 with those data types.
1910 The optional C<\%options> hash reference may contain additional
1911 options to generate the insert SQL. Currently supported options
1918 Takes either a scalar of raw SQL fields, or an array reference of
1919 field names, and adds on an SQL C<RETURNING> statement at the end.
1920 This allows you to return data generated by the insert statement
1921 (such as row IDs) without performing another C<SELECT> statement.
1922 Note, however, this is not part of the SQL standard and may not
1923 be supported by all database engines.
1927 =head2 update($table, \%fieldvals, \%where, \%options)
1929 This takes a table, hashref of field/value pairs, and an optional
1930 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1932 See the sections on L</"Inserting and Updating Arrays"> and
1933 L</"Inserting and Updating SQL"> for information on how to insert
1934 with those data types.
1936 The optional C<\%options> hash reference may contain additional
1937 options to generate the update SQL. Currently supported options
1944 See the C<returning> option to
1945 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1949 =head2 select($source, $fields, $where, $order)
1951 This returns a SQL SELECT statement and associated list of bind values, as
1952 specified by the arguments:
1958 Specification of the 'FROM' part of the statement.
1959 The argument can be either a plain scalar (interpreted as a table
1960 name, will be quoted), or an arrayref (interpreted as a list
1961 of table names, joined by commas, quoted), or a scalarref
1962 (literal SQL, not quoted).
1966 Specification of the list of fields to retrieve from
1968 The argument can be either an arrayref (interpreted as a list
1969 of field names, will be joined by commas and quoted), or a
1970 plain scalar (literal SQL, not quoted).
1971 Please observe that this API is not as flexible as that of
1972 the first argument C<$source>, for backwards compatibility reasons.
1976 Optional argument to specify the WHERE part of the query.
1977 The argument is most often a hashref, but can also be
1978 an arrayref or plain scalar --
1979 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1983 Optional argument to specify the ORDER BY part of the query.
1984 The argument can be a scalar, a hashref or an arrayref
1985 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1991 =head2 delete($table, \%where, \%options)
1993 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1994 It returns an SQL DELETE statement and list of bind values.
1996 The optional C<\%options> hash reference may contain additional
1997 options to generate the delete SQL. Currently supported options
2004 See the C<returning> option to
2005 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2009 =head2 where(\%where, $order)
2011 This is used to generate just the WHERE clause. For example,
2012 if you have an arbitrary data structure and know what the
2013 rest of your SQL is going to look like, but want an easy way
2014 to produce a WHERE clause, use this. It returns an SQL WHERE
2015 clause and list of bind values.
2018 =head2 values(\%data)
2020 This just returns the values from the hash C<%data>, in the same
2021 order that would be returned from any of the other above queries.
2022 Using this allows you to markedly speed up your queries if you
2023 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2025 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2027 Warning: This is an experimental method and subject to change.
2029 This returns arbitrarily generated SQL. It's a really basic shortcut.
2030 It will return two different things, depending on return context:
2032 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2033 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2035 These would return the following:
2037 # First calling form
2038 $stmt = "CREATE TABLE test (?, ?)";
2039 @bind = (field1, field2);
2041 # Second calling form
2042 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2044 Depending on what you're trying to do, it's up to you to choose the correct
2045 format. In this example, the second form is what you would want.
2049 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2053 ALTER SESSION SET nls_date_format = 'MM/YY'
2055 You get the idea. Strings get their case twiddled, but everything
2056 else remains verbatim.
2058 =head1 EXPORTABLE FUNCTIONS
2060 =head2 is_plain_value
2062 Determines if the supplied argument is a plain value as understood by this
2067 =item * The value is C<undef>
2069 =item * The value is a non-reference
2071 =item * The value is an object with stringification overloading
2073 =item * The value is of the form C<< { -value => $anything } >>
2077 On failure returns C<undef>, on success returns a B<scalar> reference
2078 to the original supplied argument.
2084 The stringification overloading detection is rather advanced: it takes
2085 into consideration not only the presence of a C<""> overload, but if that
2086 fails also checks for enabled
2087 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2088 on either C<0+> or C<bool>.
2090 Unfortunately testing in the field indicates that this
2091 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2092 but only when very large numbers of stringifying objects are involved.
2093 At the time of writing ( Sep 2014 ) there is no clear explanation of
2094 the direct cause, nor is there a manageably small test case that reliably
2095 reproduces the problem.
2097 If you encounter any of the following exceptions in B<random places within
2098 your application stack> - this module may be to blame:
2100 Operation "ne": no method found,
2101 left argument in overloaded package <something>,
2102 right argument in overloaded package <something>
2106 Stub found while resolving method "???" overloading """" in package <something>
2108 If you fall victim to the above - please attempt to reduce the problem
2109 to something that could be sent to the L<SQL::Abstract developers
2110 |DBIx::Class/GETTING HELP/SUPPORT>
2111 (either publicly or privately). As a workaround in the meantime you can
2112 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2113 value, which will most likely eliminate your problem (at the expense of
2114 not being able to properly detect exotic forms of stringification).
2116 This notice and environment variable will be removed in a future version,
2117 as soon as the underlying problem is found and a reliable workaround is
2122 =head2 is_literal_value
2124 Determines if the supplied argument is a literal value as understood by this
2129 =item * C<\$sql_string>
2131 =item * C<\[ $sql_string, @bind_values ]>
2135 On failure returns C<undef>, on success returns an B<array> reference
2136 containing the unpacked version of the supplied literal SQL and bind values.
2138 =head1 WHERE CLAUSES
2142 This module uses a variation on the idea from L<DBIx::Abstract>. It
2143 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2144 module is that things in arrays are OR'ed, and things in hashes
2147 The easiest way to explain is to show lots of examples. After
2148 each C<%where> hash shown, it is assumed you used:
2150 my($stmt, @bind) = $sql->where(\%where);
2152 However, note that the C<%where> hash can be used directly in any
2153 of the other functions as well, as described above.
2155 =head2 Key-value pairs
2157 So, let's get started. To begin, a simple hash:
2161 status => 'completed'
2164 Is converted to SQL C<key = val> statements:
2166 $stmt = "WHERE user = ? AND status = ?";
2167 @bind = ('nwiger', 'completed');
2169 One common thing I end up doing is having a list of values that
2170 a field can be in. To do this, simply specify a list inside of
2175 status => ['assigned', 'in-progress', 'pending'];
2178 This simple code will create the following:
2180 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2181 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2183 A field associated to an empty arrayref will be considered a
2184 logical false and will generate 0=1.
2186 =head2 Tests for NULL values
2188 If the value part is C<undef> then this is converted to SQL <IS NULL>
2197 $stmt = "WHERE user = ? AND status IS NULL";
2200 To test if a column IS NOT NULL:
2204 status => { '!=', undef },
2207 =head2 Specific comparison operators
2209 If you want to specify a different type of operator for your comparison,
2210 you can use a hashref for a given column:
2214 status => { '!=', 'completed' }
2217 Which would generate:
2219 $stmt = "WHERE user = ? AND status != ?";
2220 @bind = ('nwiger', 'completed');
2222 To test against multiple values, just enclose the values in an arrayref:
2224 status => { '=', ['assigned', 'in-progress', 'pending'] };
2226 Which would give you:
2228 "WHERE status = ? OR status = ? OR status = ?"
2231 The hashref can also contain multiple pairs, in which case it is expanded
2232 into an C<AND> of its elements:
2236 status => { '!=', 'completed', -not_like => 'pending%' }
2239 # Or more dynamically, like from a form
2240 $where{user} = 'nwiger';
2241 $where{status}{'!='} = 'completed';
2242 $where{status}{'-not_like'} = 'pending%';
2244 # Both generate this
2245 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2246 @bind = ('nwiger', 'completed', 'pending%');
2249 To get an OR instead, you can combine it with the arrayref idea:
2253 priority => [ { '=', 2 }, { '>', 5 } ]
2256 Which would generate:
2258 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2259 @bind = ('2', '5', 'nwiger');
2261 If you want to include literal SQL (with or without bind values), just use a
2262 scalar reference or reference to an arrayref as the value:
2265 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2266 date_expires => { '<' => \"now()" }
2269 Which would generate:
2271 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2272 @bind = ('11/26/2008');
2275 =head2 Logic and nesting operators
2277 In the example above,
2278 there is a subtle trap if you want to say something like
2279 this (notice the C<AND>):
2281 WHERE priority != ? AND priority != ?
2283 Because, in Perl you I<can't> do this:
2285 priority => { '!=' => 2, '!=' => 1 }
2287 As the second C<!=> key will obliterate the first. The solution
2288 is to use the special C<-modifier> form inside an arrayref:
2290 priority => [ -and => {'!=', 2},
2294 Normally, these would be joined by C<OR>, but the modifier tells it
2295 to use C<AND> instead. (Hint: You can use this in conjunction with the
2296 C<logic> option to C<new()> in order to change the way your queries
2297 work by default.) B<Important:> Note that the C<-modifier> goes
2298 B<INSIDE> the arrayref, as an extra first element. This will
2299 B<NOT> do what you think it might:
2301 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2303 Here is a quick list of equivalencies, since there is some overlap:
2306 status => {'!=', 'completed', 'not like', 'pending%' }
2307 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2310 status => {'=', ['assigned', 'in-progress']}
2311 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2312 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2316 =head2 Special operators: IN, BETWEEN, etc.
2318 You can also use the hashref format to compare a list of fields using the
2319 C<IN> comparison operator, by specifying the list as an arrayref:
2322 status => 'completed',
2323 reportid => { -in => [567, 2335, 2] }
2326 Which would generate:
2328 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2329 @bind = ('completed', '567', '2335', '2');
2331 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2334 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2335 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2336 'sqltrue' (by default: C<1=1>).
2338 In addition to the array you can supply a chunk of literal sql or
2339 literal sql with bind:
2342 customer => { -in => \[
2343 'SELECT cust_id FROM cust WHERE balance > ?',
2346 status => { -in => \'SELECT status_codes FROM states' },
2352 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2353 AND status IN ( SELECT status_codes FROM states )
2357 Finally, if the argument to C<-in> is not a reference, it will be
2358 treated as a single-element array.
2360 Another pair of operators is C<-between> and C<-not_between>,
2361 used with an arrayref of two values:
2365 completion_date => {
2366 -not_between => ['2002-10-01', '2003-02-06']
2372 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2374 Just like with C<-in> all plausible combinations of literal SQL
2378 start0 => { -between => [ 1, 2 ] },
2379 start1 => { -between => \["? AND ?", 1, 2] },
2380 start2 => { -between => \"lower(x) AND upper(y)" },
2381 start3 => { -between => [
2383 \["upper(?)", 'stuff' ],
2390 ( start0 BETWEEN ? AND ? )
2391 AND ( start1 BETWEEN ? AND ? )
2392 AND ( start2 BETWEEN lower(x) AND upper(y) )
2393 AND ( start3 BETWEEN lower(x) AND upper(?) )
2395 @bind = (1, 2, 1, 2, 'stuff');
2398 These are the two builtin "special operators"; but the
2399 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2401 =head2 Unary operators: bool
2403 If you wish to test against boolean columns or functions within your
2404 database you can use the C<-bool> and C<-not_bool> operators. For
2405 example to test the column C<is_user> being true and the column
2406 C<is_enabled> being false you would use:-
2410 -not_bool => 'is_enabled',
2415 WHERE is_user AND NOT is_enabled
2417 If a more complex combination is required, testing more conditions,
2418 then you should use the and/or operators:-
2423 -not_bool => { two=> { -rlike => 'bar' } },
2424 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2435 (NOT ( three = ? OR three > ? ))
2438 =head2 Nested conditions, -and/-or prefixes
2440 So far, we've seen how multiple conditions are joined with a top-level
2441 C<AND>. We can change this by putting the different conditions we want in
2442 hashes and then putting those hashes in an array. For example:
2447 status => { -like => ['pending%', 'dispatched'] },
2451 status => 'unassigned',
2455 This data structure would create the following:
2457 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2458 OR ( user = ? AND status = ? ) )";
2459 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2462 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2463 to change the logic inside:
2469 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2470 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2477 $stmt = "WHERE ( user = ?
2478 AND ( ( workhrs > ? AND geo = ? )
2479 OR ( workhrs < ? OR geo = ? ) ) )";
2480 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2482 =head3 Algebraic inconsistency, for historical reasons
2484 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2485 operator goes C<outside> of the nested structure; whereas when connecting
2486 several constraints on one column, the C<-and> operator goes
2487 C<inside> the arrayref. Here is an example combining both features:
2490 -and => [a => 1, b => 2],
2491 -or => [c => 3, d => 4],
2492 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2497 WHERE ( ( ( a = ? AND b = ? )
2498 OR ( c = ? OR d = ? )
2499 OR ( e LIKE ? AND e LIKE ? ) ) )
2501 This difference in syntax is unfortunate but must be preserved for
2502 historical reasons. So be careful: the two examples below would
2503 seem algebraically equivalent, but they are not
2506 { -like => 'foo%' },
2507 { -like => '%bar' },
2509 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2512 { col => { -like => 'foo%' } },
2513 { col => { -like => '%bar' } },
2515 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2518 =head2 Literal SQL and value type operators
2520 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2521 side" is a column name and the "right side" is a value (normally rendered as
2522 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2523 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2524 alter this behavior. There are several ways of doing so.
2528 This is a virtual operator that signals the string to its right side is an
2529 identifier (a column name) and not a value. For example to compare two
2530 columns you would write:
2533 priority => { '<', 2 },
2534 requestor => { -ident => 'submitter' },
2539 $stmt = "WHERE priority < ? AND requestor = submitter";
2542 If you are maintaining legacy code you may see a different construct as
2543 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2548 This is a virtual operator that signals that the construct to its right side
2549 is a value to be passed to DBI. This is for example necessary when you want
2550 to write a where clause against an array (for RDBMS that support such
2551 datatypes). For example:
2554 array => { -value => [1, 2, 3] }
2559 $stmt = 'WHERE array = ?';
2560 @bind = ([1, 2, 3]);
2562 Note that if you were to simply say:
2568 the result would probably not be what you wanted:
2570 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2575 Finally, sometimes only literal SQL will do. To include a random snippet
2576 of SQL verbatim, you specify it as a scalar reference. Consider this only
2577 as a last resort. Usually there is a better way. For example:
2580 priority => { '<', 2 },
2581 requestor => { -in => \'(SELECT name FROM hitmen)' },
2586 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2589 Note that in this example, you only get one bind parameter back, since
2590 the verbatim SQL is passed as part of the statement.
2594 Never use untrusted input as a literal SQL argument - this is a massive
2595 security risk (there is no way to check literal snippets for SQL
2596 injections and other nastyness). If you need to deal with untrusted input
2597 use literal SQL with placeholders as described next.
2599 =head3 Literal SQL with placeholders and bind values (subqueries)
2601 If the literal SQL to be inserted has placeholders and bind values,
2602 use a reference to an arrayref (yes this is a double reference --
2603 not so common, but perfectly legal Perl). For example, to find a date
2604 in Postgres you can use something like this:
2607 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2612 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2615 Note that you must pass the bind values in the same format as they are returned
2616 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2617 to C<columns>, you must provide the bind values in the
2618 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2619 scalar value; most commonly the column name, but you can use any scalar value
2620 (including references and blessed references), L<SQL::Abstract> will simply
2621 pass it through intact. So if C<bindtype> is set to C<columns> the above
2622 example will look like:
2625 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2628 Literal SQL is especially useful for nesting parenthesized clauses in the
2629 main SQL query. Here is a first example:
2631 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2635 bar => \["IN ($sub_stmt)" => @sub_bind],
2640 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2641 WHERE c2 < ? AND c3 LIKE ?))";
2642 @bind = (1234, 100, "foo%");
2644 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2645 are expressed in the same way. Of course the C<$sub_stmt> and
2646 its associated bind values can be generated through a former call
2649 my ($sub_stmt, @sub_bind)
2650 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2651 c3 => {-like => "foo%"}});
2654 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2657 In the examples above, the subquery was used as an operator on a column;
2658 but the same principle also applies for a clause within the main C<%where>
2659 hash, like an EXISTS subquery:
2661 my ($sub_stmt, @sub_bind)
2662 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2663 my %where = ( -and => [
2665 \["EXISTS ($sub_stmt)" => @sub_bind],
2670 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2671 WHERE c1 = ? AND c2 > t0.c0))";
2675 Observe that the condition on C<c2> in the subquery refers to
2676 column C<t0.c0> of the main query: this is I<not> a bind
2677 value, so we have to express it through a scalar ref.
2678 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2679 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2680 what we wanted here.
2682 Finally, here is an example where a subquery is used
2683 for expressing unary negation:
2685 my ($sub_stmt, @sub_bind)
2686 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2687 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2689 lname => {like => '%son%'},
2690 \["NOT ($sub_stmt)" => @sub_bind],
2695 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2696 @bind = ('%son%', 10, 20)
2698 =head3 Deprecated usage of Literal SQL
2700 Below are some examples of archaic use of literal SQL. It is shown only as
2701 reference for those who deal with legacy code. Each example has a much
2702 better, cleaner and safer alternative that users should opt for in new code.
2708 my %where = ( requestor => \'IS NOT NULL' )
2710 $stmt = "WHERE requestor IS NOT NULL"
2712 This used to be the way of generating NULL comparisons, before the handling
2713 of C<undef> got formalized. For new code please use the superior syntax as
2714 described in L</Tests for NULL values>.
2718 my %where = ( requestor => \'= submitter' )
2720 $stmt = "WHERE requestor = submitter"
2722 This used to be the only way to compare columns. Use the superior L</-ident>
2723 method for all new code. For example an identifier declared in such a way
2724 will be properly quoted if L</quote_char> is properly set, while the legacy
2725 form will remain as supplied.
2729 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2731 $stmt = "WHERE completed > ? AND is_ready"
2732 @bind = ('2012-12-21')
2734 Using an empty string literal used to be the only way to express a boolean.
2735 For all new code please use the much more readable
2736 L<-bool|/Unary operators: bool> operator.
2742 These pages could go on for a while, since the nesting of the data
2743 structures this module can handle are pretty much unlimited (the
2744 module implements the C<WHERE> expansion as a recursive function
2745 internally). Your best bet is to "play around" with the module a
2746 little to see how the data structures behave, and choose the best
2747 format for your data based on that.
2749 And of course, all the values above will probably be replaced with
2750 variables gotten from forms or the command line. After all, if you
2751 knew everything ahead of time, you wouldn't have to worry about
2752 dynamically-generating SQL and could just hardwire it into your
2755 =head1 ORDER BY CLAUSES
2757 Some functions take an order by clause. This can either be a scalar (just a
2758 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2759 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2762 Given | Will Generate
2763 ---------------------------------------------------------------
2765 'colA' | ORDER BY colA
2767 [qw/colA colB/] | ORDER BY colA, colB
2769 {-asc => 'colA'} | ORDER BY colA ASC
2771 {-desc => 'colB'} | ORDER BY colB DESC
2773 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2775 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2777 \'colA DESC' | ORDER BY colA DESC
2779 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2780 | /* ...with $x bound to ? */
2783 { -asc => 'colA' }, | colA ASC,
2784 { -desc => [qw/colB/] }, | colB DESC,
2785 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2786 \'colE DESC', | colE DESC,
2787 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2788 ] | /* ...with $x bound to ? */
2789 ===============================================================
2793 =head1 SPECIAL OPERATORS
2795 my $sqlmaker = SQL::Abstract->new(special_ops => [
2799 my ($self, $field, $op, $arg) = @_;
2805 handler => 'method_name',
2809 A "special operator" is a SQL syntactic clause that can be
2810 applied to a field, instead of a usual binary operator.
2813 WHERE field IN (?, ?, ?)
2814 WHERE field BETWEEN ? AND ?
2815 WHERE MATCH(field) AGAINST (?, ?)
2817 Special operators IN and BETWEEN are fairly standard and therefore
2818 are builtin within C<SQL::Abstract> (as the overridable methods
2819 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2820 like the MATCH .. AGAINST example above which is specific to MySQL,
2821 you can write your own operator handlers - supply a C<special_ops>
2822 argument to the C<new> method. That argument takes an arrayref of
2823 operator definitions; each operator definition is a hashref with two
2830 the regular expression to match the operator
2834 Either a coderef or a plain scalar method name. In both cases
2835 the expected return is C<< ($sql, @bind) >>.
2837 When supplied with a method name, it is simply called on the
2838 L<SQL::Abstract> object as:
2840 $self->$method_name($field, $op, $arg)
2844 $field is the LHS of the operator
2845 $op is the part that matched the handler regex
2848 When supplied with a coderef, it is called as:
2850 $coderef->($self, $field, $op, $arg)
2855 For example, here is an implementation
2856 of the MATCH .. AGAINST syntax for MySQL
2858 my $sqlmaker = SQL::Abstract->new(special_ops => [
2860 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2861 {regex => qr/^match$/i,
2863 my ($self, $field, $op, $arg) = @_;
2864 $arg = [$arg] if not ref $arg;
2865 my $label = $self->_quote($field);
2866 my ($placeholder) = $self->_convert('?');
2867 my $placeholders = join ", ", (($placeholder) x @$arg);
2868 my $sql = $self->_sqlcase('match') . " ($label) "
2869 . $self->_sqlcase('against') . " ($placeholders) ";
2870 my @bind = $self->_bindtype($field, @$arg);
2871 return ($sql, @bind);
2878 =head1 UNARY OPERATORS
2880 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2884 my ($self, $op, $arg) = @_;
2890 handler => 'method_name',
2894 A "unary operator" is a SQL syntactic clause that can be
2895 applied to a field - the operator goes before the field
2897 You can write your own operator handlers - supply a C<unary_ops>
2898 argument to the C<new> method. That argument takes an arrayref of
2899 operator definitions; each operator definition is a hashref with two
2906 the regular expression to match the operator
2910 Either a coderef or a plain scalar method name. In both cases
2911 the expected return is C<< $sql >>.
2913 When supplied with a method name, it is simply called on the
2914 L<SQL::Abstract> object as:
2916 $self->$method_name($op, $arg)
2920 $op is the part that matched the handler regex
2921 $arg is the RHS or argument of the operator
2923 When supplied with a coderef, it is called as:
2925 $coderef->($self, $op, $arg)
2933 Thanks to some benchmarking by Mark Stosberg, it turns out that
2934 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2935 I must admit this wasn't an intentional design issue, but it's a
2936 byproduct of the fact that you get to control your C<DBI> handles
2939 To maximize performance, use a code snippet like the following:
2941 # prepare a statement handle using the first row
2942 # and then reuse it for the rest of the rows
2944 for my $href (@array_of_hashrefs) {
2945 $stmt ||= $sql->insert('table', $href);
2946 $sth ||= $dbh->prepare($stmt);
2947 $sth->execute($sql->values($href));
2950 The reason this works is because the keys in your C<$href> are sorted
2951 internally by B<SQL::Abstract>. Thus, as long as your data retains
2952 the same structure, you only have to generate the SQL the first time
2953 around. On subsequent queries, simply use the C<values> function provided
2954 by this module to return your values in the correct order.
2956 However this depends on the values having the same type - if, for
2957 example, the values of a where clause may either have values
2958 (resulting in sql of the form C<column = ?> with a single bind
2959 value), or alternatively the values might be C<undef> (resulting in
2960 sql of the form C<column IS NULL> with no bind value) then the
2961 caching technique suggested will not work.
2965 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2966 really like this part (I do, at least). Building up a complex query
2967 can be as simple as the following:
2974 use CGI::FormBuilder;
2977 my $form = CGI::FormBuilder->new(...);
2978 my $sql = SQL::Abstract->new;
2980 if ($form->submitted) {
2981 my $field = $form->field;
2982 my $id = delete $field->{id};
2983 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2986 Of course, you would still have to connect using C<DBI> to run the
2987 query, but the point is that if you make your form look like your
2988 table, the actual query script can be extremely simplistic.
2990 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2991 a fast interface to returning and formatting data. I frequently
2992 use these three modules together to write complex database query
2993 apps in under 50 lines.
2995 =head1 HOW TO CONTRIBUTE
2997 Contributions are always welcome, in all usable forms (we especially
2998 welcome documentation improvements). The delivery methods include git-
2999 or unified-diff formatted patches, GitHub pull requests, or plain bug
3000 reports either via RT or the Mailing list. Contributors are generally
3001 granted full access to the official repository after their first several
3002 patches pass successful review.
3004 This project is maintained in a git repository. The code and related tools are
3005 accessible at the following locations:
3009 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3011 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3013 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3015 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3021 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3022 Great care has been taken to preserve the I<published> behavior
3023 documented in previous versions in the 1.* family; however,
3024 some features that were previously undocumented, or behaved
3025 differently from the documentation, had to be changed in order
3026 to clarify the semantics. Hence, client code that was relying
3027 on some dark areas of C<SQL::Abstract> v1.*
3028 B<might behave differently> in v1.50.
3030 The main changes are:
3036 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3040 support for the { operator => \"..." } construct (to embed literal SQL)
3044 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3048 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3052 defensive programming: check arguments
3056 fixed bug with global logic, which was previously implemented
3057 through global variables yielding side-effects. Prior versions would
3058 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3059 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3060 Now this is interpreted
3061 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3066 fixed semantics of _bindtype on array args
3070 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3071 we just avoid shifting arrays within that tree.
3075 dropped the C<_modlogic> function
3079 =head1 ACKNOWLEDGEMENTS
3081 There are a number of individuals that have really helped out with
3082 this module. Unfortunately, most of them submitted bugs via CPAN
3083 so I have no idea who they are! But the people I do know are:
3085 Ash Berlin (order_by hash term support)
3086 Matt Trout (DBIx::Class support)
3087 Mark Stosberg (benchmarking)
3088 Chas Owens (initial "IN" operator support)
3089 Philip Collins (per-field SQL functions)
3090 Eric Kolve (hashref "AND" support)
3091 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3092 Dan Kubb (support for "quote_char" and "name_sep")
3093 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3094 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3095 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3096 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3097 Oliver Charles (support for "RETURNING" after "INSERT")
3103 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3107 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3109 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3111 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3112 While not an official support venue, C<DBIx::Class> makes heavy use of
3113 C<SQL::Abstract>, and as such list members there are very familiar with
3114 how to create queries.
3118 This module is free software; you may copy this under the same
3119 terms as perl itself (either the GNU General Public License or
3120 the Artistic License)