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} = {};
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 => [ '=', { -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, undef);
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, $default_scalar_to) = @_;
529 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
530 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
531 return undef unless defined($expr);
532 if (ref($expr) eq 'HASH') {
533 if (keys %$expr > 1) {
537 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
541 return undef unless keys %$expr;
542 return $self->_expand_expr_hashpair(%$expr, $logic);
544 if (ref($expr) eq 'ARRAY') {
545 my $logic = lc($logic || $self->{logic});
546 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
549 (ref($_) eq 'ARRAY' and @$_)
550 or (ref($_) eq 'HASH' and %$_)
556 while (my ($el) = splice @expr, 0, 1) {
557 puke "Supplying an empty left hand side argument is not supported in array-pairs"
558 unless defined($el) and length($el);
559 my $elref = ref($el);
561 local $Expand_Depth = 0;
562 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
563 } elsif ($elref eq 'ARRAY') {
564 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
565 } elsif (my $l = is_literal_value($el)) {
566 push @res, { -literal => $l };
567 } elsif ($elref eq 'HASH') {
568 local $Expand_Depth = 0;
569 push @res, grep defined, $self->_expand_expr($el) if %$el;
574 return { -op => [ $logic, @res ] };
576 if (my $literal = is_literal_value($expr)) {
577 return +{ -literal => $literal };
579 if (!ref($expr) or Scalar::Util::blessed($expr)) {
580 if (my $d = $Default_Scalar_To) {
581 return $self->_expand_expr({ $d => $expr });
583 if (my $m = our $Cur_Col_Meta) {
584 return +{ -bind => [ $m, $expr ] };
586 return +{ -bind => [ undef, $expr ] };
591 sub _expand_expr_hashpair {
592 my ($self, $k, $v, $logic) = @_;
593 unless (defined($k) and length($k)) {
594 if (defined($k) and my $literal = is_literal_value($v)) {
595 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
596 return { -literal => $literal };
598 puke "Supplying an empty left hand side argument is not supported";
601 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
602 if ($k =~ s/ [_\s]? \d+ $//x ) {
603 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
604 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
607 # DBIx::Class requires a nest warning to be emitted once but the private
608 # method it overrode to do so no longer exists
609 if ($self->{is_dbic_sqlmaker}) {
610 unless (our $Nest_Warned) {
612 "-nest in search conditions is deprecated, you most probably wanted:\n"
613 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
618 return $self->_expand_expr($v);
622 return $self->_expand_expr($v);
624 puke "-bool => undef not supported" unless defined($v);
625 return { -ident => $v };
628 return { -op => [ 'not', $self->_expand_expr($v) ] };
630 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
633 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
636 if (my ($logic) = $k =~ /^-(and|or)$/i) {
637 if (ref($v) eq 'HASH') {
638 return $self->_expand_expr($v, $logic);
640 if (ref($v) eq 'ARRAY') {
641 return $self->_expand_expr($v, $logic);
646 $op =~ s/^-// if length($op) > 1;
648 # top level special ops are illegal in general
649 # note that, arguably, if it makes no sense at top level, it also
650 # makes no sense on the other side of an = sign or similar but DBIC
651 # gets disappointingly upset if I disallow it
653 (our $Expand_Depth) == 1
654 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
656 puke "Illegal use of top-level '-$op'"
658 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
659 return { -op => [ $op, $v ] };
662 if ($k eq '-value') {
663 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
665 if (my $custom = $self->{expand_unary}{$k}) {
666 return $self->$custom($v);
668 if ($self->{render}{$k}) {
674 and (keys %$v)[0] =~ /^-/
676 my ($func) = $k =~ /^-(.*)$/;
677 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
678 return +{ -op => [ $func, $self->_expand_expr($v) ] };
680 return +{ -func => [ $func, $self->_expand_expr($v) ] };
682 if (!ref($v) or is_literal_value($v)) {
683 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
690 and exists $v->{-value}
691 and not defined $v->{-value}
694 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
696 if (!ref($v) or Scalar::Util::blessed($v)) {
697 my $d = our $Default_Scalar_To;
702 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
706 if (ref($v) eq 'HASH') {
710 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
714 return undef unless keys %$v;
718 $self->_assert_pass_injection_guard($vk);
719 if ($vk =~ s/ [_\s]? \d+ $//x ) {
720 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
721 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
723 if ($vk =~ /^(?:not[ _])?between$/) {
724 local our $Cur_Col_Meta = $k;
725 my @rhs = map $self->_expand_expr($_),
726 ref($vv) eq 'ARRAY' ? @$vv : $vv;
728 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
730 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
732 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
735 join(' ', split '_', $vk),
740 if ($vk =~ /^(?:not[ _])?in$/) {
741 if (my $literal = is_literal_value($vv)) {
742 my ($sql, @bind) = @$literal;
743 my $opened_sql = $self->_open_outer_paren($sql);
745 $vk, { -ident => $k },
746 [ { -literal => [ $opened_sql, @bind ] } ]
750 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
751 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
752 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
753 . 'will emit the logically correct SQL instead of raising this exception)'
755 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
757 my @rhs = map $self->_expand_expr($_),
758 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
759 map { defined($_) ? $_: puke($undef_err) }
760 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
761 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
764 join(' ', split '_', $vk),
769 if ($vk eq 'ident') {
770 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
771 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
779 if ($vk eq 'value') {
780 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
784 { -bind => [ $k, $vv ] }
787 if ($vk =~ /^is(?:[ _]not)?$/) {
788 puke "$vk can only take undef as argument"
792 and exists($vv->{-value})
793 and !defined($vv->{-value})
796 return +{ -op => [ $vk.' null', { -ident => $k } ] };
798 if ($vk =~ /^(and|or)$/) {
799 if (ref($vv) eq 'HASH') {
802 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
807 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
808 return { -op => [ $vk, { -ident => $k }, $vv ] };
810 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
814 { -op => [ $vk, $vv ] }
817 if (ref($vv) eq 'ARRAY') {
818 my ($logic, @values) = (
819 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
824 $vk =~ $self->{inequality_op}
825 or join(' ', split '_', $vk) =~ $self->{not_like_op}
827 if (lc($logic) eq '-or' and @values > 1) {
828 my $op = uc join ' ', split '_', $vk;
829 belch "A multi-element arrayref as an argument to the inequality op '$op' "
830 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
831 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
836 # try to DWIM on equality operators
837 my $op = join ' ', split '_', $vk;
839 $op =~ $self->{equality_op} ? $self->sqlfalse
840 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
841 : $op =~ $self->{inequality_op} ? $self->sqltrue
842 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
843 : puke "operator '$op' applied on an empty array (field '$k')";
847 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
855 and exists $vv->{-value}
856 and not defined $vv->{-value}
859 my $op = join ' ', split '_', $vk;
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', { -ident => $k } ] };
869 local our $Cur_Col_Meta = $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, $where, $logic) = @_;
908 # Special case: top level simple string treated as literal
910 my $where_exp = (ref($where)
911 ? $self->_expand_expr($where, $logic)
912 : { -literal => [ $where ] });
914 # dispatch expanded expression
916 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
917 # DBIx::Class used to call _recurse_where in scalar context
918 # something else might too...
920 return ($sql, @bind);
923 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
929 my ($self, $ident) = @_;
931 return $self->_convert($self->_quote($ident));
934 my %unop_postfix = map +($_ => 1),
935 'is null', 'is not null',
943 my ($self, $args) = @_;
944 my ($left, $low, $high) = @$args;
945 my ($rhsql, @rhbind) = do {
947 puke "Single arg to between must be a literal"
948 unless $low->{-literal};
951 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
952 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
953 @{$l}[1..$#$l], @{$h}[1..$#$h])
956 my ($lhsql, @lhbind) = $self->render_aqt($left);
958 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
962 }), 'between', 'not between'),
966 my ($self, $args) = @_;
967 my ($lhs, $rhs) = @$args;
970 my ($sql, @bind) = $self->render_aqt($_);
971 push @in_bind, @bind;
974 my ($lhsql, @lbind) = $self->render_aqt($lhs);
976 $lhsql.' '.$self->_sqlcase($op).' ( '
987 my ($op, @args) = @$v;
988 $op =~ s/^-// if length($op) > 1;
990 if (my $h = $special{$op}) {
991 return $self->$h(\@args);
993 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
994 if ($us and @args > 1) {
995 puke "Special op '${op}' requires first value to be identifier"
996 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
997 local our $Expand_Depth = 1;
998 return $self->${\($us->{handler})}($k, $op, $args[1]);
1000 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1001 return $self->${\($us->{handler})}($op, $args[0]);
1003 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1004 if (@args == 1 and $op !~ /^(and|or)$/) {
1005 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1006 my $op_sql = $self->_sqlcase($final_op);
1008 $unop_postfix{lc($final_op)}
1009 ? "${expr_sql} ${op_sql}"
1010 : "${op_sql} ${expr_sql}"
1012 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1014 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1015 return '' unless @parts;
1016 my $is_andor = !!($op =~ /^(and|or)$/);
1017 return @{$parts[0]} if $is_andor and @parts == 1;
1018 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1019 ' '.$self->_sqlcase($final_op).' ',
1024 map @{$_}[1..$#$_], @parts
1031 my ($self, $list) = @_;
1032 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
1033 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1037 my ($self, $rest) = @_;
1038 my ($func, @args) = @$rest;
1042 push @arg_sql, shift @x;
1044 } map [ $self->render_aqt($_) ], @args;
1045 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1049 my ($self, $bind) = @_;
1050 return ($self->_convert('?'), $self->_bindtype(@$bind));
1053 sub _render_literal {
1054 my ($self, $literal) = @_;
1055 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1059 # Some databases (SQLite) treat col IN (1, 2) different from
1060 # col IN ( (1, 2) ). Use this to strip all outer parens while
1061 # adding them back in the corresponding method
1062 sub _open_outer_paren {
1063 my ($self, $sql) = @_;
1065 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1067 # there are closing parens inside, need the heavy duty machinery
1068 # to reevaluate the extraction starting from $sql (full reevaluation)
1069 if ($inner =~ /\)/) {
1070 require Text::Balanced;
1072 my (undef, $remainder) = do {
1073 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1075 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1078 # the entire expression needs to be a balanced bracketed thing
1079 # (after an extract no remainder sans trailing space)
1080 last if defined $remainder and $remainder =~ /\S/;
1090 #======================================================================
1092 #======================================================================
1094 sub _expand_order_by {
1095 my ($self, $arg) = @_;
1097 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1099 my $expander = sub {
1100 my ($self, $dir, $expr) = @_;
1101 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1102 foreach my $arg (@to_expand) {
1106 and grep /^-(asc|desc)$/, keys %$arg
1108 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1111 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1112 map $self->expand_expr($_, -ident),
1113 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1114 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1117 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1118 sub { shift->$expander(asc => @_) },
1119 sub { shift->$expander(desc => @_) },
1122 return $self->$expander(undef, $arg);
1126 my ($self, $arg) = @_;
1128 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1130 my ($sql, @bind) = $self->render_aqt($expanded);
1132 return '' unless length($sql);
1134 my $final_sql = $self->_sqlcase(' order by ').$sql;
1136 return wantarray ? ($final_sql, @bind) : $final_sql;
1139 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1141 sub _order_by_chunks {
1142 my ($self, $arg) = @_;
1144 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1146 return $self->_chunkify_order_by($expanded);
1149 sub _chunkify_order_by {
1150 my ($self, $expanded) = @_;
1152 return grep length, $self->render_aqt($expanded)
1153 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1156 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1157 return map $self->_chunkify_order_by($_), @$l;
1159 return [ $self->render_aqt($_) ];
1163 #======================================================================
1164 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1165 #======================================================================
1171 $self->_expand_maybe_list_expr($from, undef, -ident)
1176 #======================================================================
1178 #======================================================================
1180 sub _expand_maybe_list_expr {
1181 my ($self, $expr, $logic, $default) = @_;
1183 if (ref($expr) eq 'ARRAY') {
1185 map $self->expand_expr($_, $default), @$expr
1192 return $self->expand_expr($e, $default);
1195 # highly optimized, as it's called way too often
1197 # my ($self, $label) = @_;
1199 return '' unless defined $_[1];
1200 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1201 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1203 unless ($_[0]->{quote_char}) {
1204 if (ref($_[1]) eq 'ARRAY') {
1205 return join($_[0]->{name_sep}||'.', @{$_[1]});
1207 $_[0]->_assert_pass_injection_guard($_[1]);
1212 my $qref = ref $_[0]->{quote_char};
1214 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1215 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1216 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1218 my $esc = $_[0]->{escape_char} || $r;
1220 # parts containing * are naturally unquoted
1222 $_[0]->{name_sep}||'',
1226 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1228 (ref($_[1]) eq 'ARRAY'
1232 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1240 # Conversion, if applicable
1242 #my ($self, $arg) = @_;
1243 if ($_[0]->{convert_where}) {
1244 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1251 #my ($self, $col, @vals) = @_;
1252 # called often - tighten code
1253 return $_[0]->{bindtype} eq 'columns'
1254 ? map {[$_[1], $_]} @_[2 .. $#_]
1259 # Dies if any element of @bind is not in [colname => value] format
1260 # if bindtype is 'columns'.
1261 sub _assert_bindval_matches_bindtype {
1262 # my ($self, @bind) = @_;
1264 if ($self->{bindtype} eq 'columns') {
1266 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1267 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1273 sub _join_sql_clauses {
1274 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1276 if (@$clauses_aref > 1) {
1277 my $join = " " . $self->_sqlcase($logic) . " ";
1278 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1279 return ($sql, @$bind_aref);
1281 elsif (@$clauses_aref) {
1282 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1285 return (); # if no SQL, ignore @$bind_aref
1290 # Fix SQL case, if so requested
1292 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1293 # don't touch the argument ... crooked logic, but let's not change it!
1294 return $_[0]->{case} ? $_[1] : uc($_[1]);
1298 #======================================================================
1299 # DISPATCHING FROM REFKIND
1300 #======================================================================
1303 my ($self, $data) = @_;
1305 return 'UNDEF' unless defined $data;
1307 # blessed objects are treated like scalars
1308 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1310 return 'SCALAR' unless $ref;
1313 while ($ref eq 'REF') {
1315 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1319 return ($ref||'SCALAR') . ('REF' x $n_steps);
1323 my ($self, $data) = @_;
1324 my @try = ($self->_refkind($data));
1325 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1326 push @try, 'FALLBACK';
1330 sub _METHOD_FOR_refkind {
1331 my ($self, $meth_prefix, $data) = @_;
1334 for (@{$self->_try_refkind($data)}) {
1335 $method = $self->can($meth_prefix."_".$_)
1339 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1343 sub _SWITCH_refkind {
1344 my ($self, $data, $dispatch_table) = @_;
1347 for (@{$self->_try_refkind($data)}) {
1348 $coderef = $dispatch_table->{$_}
1352 puke "no dispatch entry for ".$self->_refkind($data)
1361 #======================================================================
1362 # VALUES, GENERATE, AUTOLOAD
1363 #======================================================================
1365 # LDNOTE: original code from nwiger, didn't touch code in that section
1366 # I feel the AUTOLOAD stuff should not be the default, it should
1367 # only be activated on explicit demand by user.
1371 my $data = shift || return;
1372 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1373 unless ref $data eq 'HASH';
1376 foreach my $k (sort keys %$data) {
1377 my $v = $data->{$k};
1378 $self->_SWITCH_refkind($v, {
1380 if ($self->{array_datatypes}) { # array datatype
1381 push @all_bind, $self->_bindtype($k, $v);
1383 else { # literal SQL with bind
1384 my ($sql, @bind) = @$v;
1385 $self->_assert_bindval_matches_bindtype(@bind);
1386 push @all_bind, @bind;
1389 ARRAYREFREF => sub { # literal SQL with bind
1390 my ($sql, @bind) = @${$v};
1391 $self->_assert_bindval_matches_bindtype(@bind);
1392 push @all_bind, @bind;
1394 SCALARREF => sub { # literal SQL without bind
1396 SCALAR_or_UNDEF => sub {
1397 push @all_bind, $self->_bindtype($k, $v);
1408 my(@sql, @sqlq, @sqlv);
1412 if ($ref eq 'HASH') {
1413 for my $k (sort keys %$_) {
1416 my $label = $self->_quote($k);
1417 if ($r eq 'ARRAY') {
1418 # literal SQL with bind
1419 my ($sql, @bind) = @$v;
1420 $self->_assert_bindval_matches_bindtype(@bind);
1421 push @sqlq, "$label = $sql";
1423 } elsif ($r eq 'SCALAR') {
1424 # literal SQL without bind
1425 push @sqlq, "$label = $$v";
1427 push @sqlq, "$label = ?";
1428 push @sqlv, $self->_bindtype($k, $v);
1431 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1432 } elsif ($ref eq 'ARRAY') {
1433 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1436 if ($r eq 'ARRAY') { # literal SQL with bind
1437 my ($sql, @bind) = @$v;
1438 $self->_assert_bindval_matches_bindtype(@bind);
1441 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1442 # embedded literal SQL
1449 push @sql, '(' . join(', ', @sqlq) . ')';
1450 } elsif ($ref eq 'SCALAR') {
1454 # strings get case twiddled
1455 push @sql, $self->_sqlcase($_);
1459 my $sql = join ' ', @sql;
1461 # this is pretty tricky
1462 # if ask for an array, return ($stmt, @bind)
1463 # otherwise, s/?/shift @sqlv/ to put it inline
1465 return ($sql, @sqlv);
1467 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1468 ref $d ? $d->[1] : $d/e;
1477 # This allows us to check for a local, then _form, attr
1479 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1480 return $self->generate($name, @_);
1491 SQL::Abstract - Generate SQL from Perl data structures
1497 my $sql = SQL::Abstract->new;
1499 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1501 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1503 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1505 my($stmt, @bind) = $sql->delete($table, \%where);
1507 # Then, use these in your DBI statements
1508 my $sth = $dbh->prepare($stmt);
1509 $sth->execute(@bind);
1511 # Just generate the WHERE clause
1512 my($stmt, @bind) = $sql->where(\%where, $order);
1514 # Return values in the same order, for hashed queries
1515 # See PERFORMANCE section for more details
1516 my @bind = $sql->values(\%fieldvals);
1520 This module was inspired by the excellent L<DBIx::Abstract>.
1521 However, in using that module I found that what I really wanted
1522 to do was generate SQL, but still retain complete control over my
1523 statement handles and use the DBI interface. So, I set out to
1524 create an abstract SQL generation module.
1526 While based on the concepts used by L<DBIx::Abstract>, there are
1527 several important differences, especially when it comes to WHERE
1528 clauses. I have modified the concepts used to make the SQL easier
1529 to generate from Perl data structures and, IMO, more intuitive.
1530 The underlying idea is for this module to do what you mean, based
1531 on the data structures you provide it. The big advantage is that
1532 you don't have to modify your code every time your data changes,
1533 as this module figures it out.
1535 To begin with, an SQL INSERT is as easy as just specifying a hash
1536 of C<key=value> pairs:
1539 name => 'Jimbo Bobson',
1540 phone => '123-456-7890',
1541 address => '42 Sister Lane',
1542 city => 'St. Louis',
1543 state => 'Louisiana',
1546 The SQL can then be generated with this:
1548 my($stmt, @bind) = $sql->insert('people', \%data);
1550 Which would give you something like this:
1552 $stmt = "INSERT INTO people
1553 (address, city, name, phone, state)
1554 VALUES (?, ?, ?, ?, ?)";
1555 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1556 '123-456-7890', 'Louisiana');
1558 These are then used directly in your DBI code:
1560 my $sth = $dbh->prepare($stmt);
1561 $sth->execute(@bind);
1563 =head2 Inserting and Updating Arrays
1565 If your database has array types (like for example Postgres),
1566 activate the special option C<< array_datatypes => 1 >>
1567 when creating the C<SQL::Abstract> object.
1568 Then you may use an arrayref to insert and update database array types:
1570 my $sql = SQL::Abstract->new(array_datatypes => 1);
1572 planets => [qw/Mercury Venus Earth Mars/]
1575 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1579 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1581 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1584 =head2 Inserting and Updating SQL
1586 In order to apply SQL functions to elements of your C<%data> you may
1587 specify a reference to an arrayref for the given hash value. For example,
1588 if you need to execute the Oracle C<to_date> function on a value, you can
1589 say something like this:
1593 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1596 The first value in the array is the actual SQL. Any other values are
1597 optional and would be included in the bind values array. This gives
1600 my($stmt, @bind) = $sql->insert('people', \%data);
1602 $stmt = "INSERT INTO people (name, date_entered)
1603 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1604 @bind = ('Bill', '03/02/2003');
1606 An UPDATE is just as easy, all you change is the name of the function:
1608 my($stmt, @bind) = $sql->update('people', \%data);
1610 Notice that your C<%data> isn't touched; the module will generate
1611 the appropriately quirky SQL for you automatically. Usually you'll
1612 want to specify a WHERE clause for your UPDATE, though, which is
1613 where handling C<%where> hashes comes in handy...
1615 =head2 Complex where statements
1617 This module can generate pretty complicated WHERE statements
1618 easily. For example, simple C<key=value> pairs are taken to mean
1619 equality, and if you want to see if a field is within a set
1620 of values, you can use an arrayref. Let's say we wanted to
1621 SELECT some data based on this criteria:
1624 requestor => 'inna',
1625 worker => ['nwiger', 'rcwe', 'sfz'],
1626 status => { '!=', 'completed' }
1629 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1631 The above would give you something like this:
1633 $stmt = "SELECT * FROM tickets WHERE
1634 ( requestor = ? ) AND ( status != ? )
1635 AND ( worker = ? OR worker = ? OR worker = ? )";
1636 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1638 Which you could then use in DBI code like so:
1640 my $sth = $dbh->prepare($stmt);
1641 $sth->execute(@bind);
1647 The methods are simple. There's one for every major SQL operation,
1648 and a constructor you use first. The arguments are specified in a
1649 similar order for each method (table, then fields, then a where
1650 clause) to try and simplify things.
1652 =head2 new(option => 'value')
1654 The C<new()> function takes a list of options and values, and returns
1655 a new B<SQL::Abstract> object which can then be used to generate SQL
1656 through the methods below. The options accepted are:
1662 If set to 'lower', then SQL will be generated in all lowercase. By
1663 default SQL is generated in "textbook" case meaning something like:
1665 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1667 Any setting other than 'lower' is ignored.
1671 This determines what the default comparison operator is. By default
1672 it is C<=>, meaning that a hash like this:
1674 %where = (name => 'nwiger', email => 'nate@wiger.org');
1676 Will generate SQL like this:
1678 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1680 However, you may want loose comparisons by default, so if you set
1681 C<cmp> to C<like> you would get SQL such as:
1683 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1685 You can also override the comparison on an individual basis - see
1686 the huge section on L</"WHERE CLAUSES"> at the bottom.
1688 =item sqltrue, sqlfalse
1690 Expressions for inserting boolean values within SQL statements.
1691 By default these are C<1=1> and C<1=0>. They are used
1692 by the special operators C<-in> and C<-not_in> for generating
1693 correct SQL even when the argument is an empty array (see below).
1697 This determines the default logical operator for multiple WHERE
1698 statements in arrays or hashes. If absent, the default logic is "or"
1699 for arrays, and "and" for hashes. This means that a WHERE
1703 event_date => {'>=', '2/13/99'},
1704 event_date => {'<=', '4/24/03'},
1707 will generate SQL like this:
1709 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1711 This is probably not what you want given this query, though (look
1712 at the dates). To change the "OR" to an "AND", simply specify:
1714 my $sql = SQL::Abstract->new(logic => 'and');
1716 Which will change the above C<WHERE> to:
1718 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1720 The logic can also be changed locally by inserting
1721 a modifier in front of an arrayref:
1723 @where = (-and => [event_date => {'>=', '2/13/99'},
1724 event_date => {'<=', '4/24/03'} ]);
1726 See the L</"WHERE CLAUSES"> section for explanations.
1730 This will automatically convert comparisons using the specified SQL
1731 function for both column and value. This is mostly used with an argument
1732 of C<upper> or C<lower>, so that the SQL will have the effect of
1733 case-insensitive "searches". For example, this:
1735 $sql = SQL::Abstract->new(convert => 'upper');
1736 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1738 Will turn out the following SQL:
1740 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1742 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1743 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1744 not validate this option; it will just pass through what you specify verbatim).
1748 This is a kludge because many databases suck. For example, you can't
1749 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1750 Instead, you have to use C<bind_param()>:
1752 $sth->bind_param(1, 'reg data');
1753 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1755 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1756 which loses track of which field each slot refers to. Fear not.
1758 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1759 Currently, you can specify either C<normal> (default) or C<columns>. If you
1760 specify C<columns>, you will get an array that looks like this:
1762 my $sql = SQL::Abstract->new(bindtype => 'columns');
1763 my($stmt, @bind) = $sql->insert(...);
1766 [ 'column1', 'value1' ],
1767 [ 'column2', 'value2' ],
1768 [ 'column3', 'value3' ],
1771 You can then iterate through this manually, using DBI's C<bind_param()>.
1773 $sth->prepare($stmt);
1776 my($col, $data) = @$_;
1777 if ($col eq 'details' || $col eq 'comments') {
1778 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1779 } elsif ($col eq 'image') {
1780 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1782 $sth->bind_param($i, $data);
1786 $sth->execute; # execute without @bind now
1788 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1789 Basically, the advantage is still that you don't have to care which fields
1790 are or are not included. You could wrap that above C<for> loop in a simple
1791 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1792 get a layer of abstraction over manual SQL specification.
1794 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1795 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1796 will expect the bind values in this format.
1800 This is the character that a table or column name will be quoted
1801 with. By default this is an empty string, but you could set it to
1802 the character C<`>, to generate SQL like this:
1804 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1806 Alternatively, you can supply an array ref of two items, the first being the left
1807 hand quote character, and the second the right hand quote character. For
1808 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1809 that generates SQL like this:
1811 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1813 Quoting is useful if you have tables or columns names that are reserved
1814 words in your database's SQL dialect.
1818 This is the character that will be used to escape L</quote_char>s appearing
1819 in an identifier before it has been quoted.
1821 The parameter default in case of a single L</quote_char> character is the quote
1824 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1825 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1826 of the B<opening (left)> L</quote_char> within the identifier are currently left
1827 untouched. The default for opening-closing-style quotes may change in future
1828 versions, thus you are B<strongly encouraged> to specify the escape character
1833 This is the character that separates a table and column name. It is
1834 necessary to specify this when the C<quote_char> option is selected,
1835 so that tables and column names can be individually quoted like this:
1837 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1839 =item injection_guard
1841 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1842 column name specified in a query structure. This is a safety mechanism to avoid
1843 injection attacks when mishandling user input e.g.:
1845 my %condition_as_column_value_pairs = get_values_from_user();
1846 $sqla->select( ... , \%condition_as_column_value_pairs );
1848 If the expression matches an exception is thrown. Note that literal SQL
1849 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1851 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1853 =item array_datatypes
1855 When this option is true, arrayrefs in INSERT or UPDATE are
1856 interpreted as array datatypes and are passed directly
1858 When this option is false, arrayrefs are interpreted
1859 as literal SQL, just like refs to arrayrefs
1860 (but this behavior is for backwards compatibility; when writing
1861 new queries, use the "reference to arrayref" syntax
1867 Takes a reference to a list of "special operators"
1868 to extend the syntax understood by L<SQL::Abstract>.
1869 See section L</"SPECIAL OPERATORS"> for details.
1873 Takes a reference to a list of "unary operators"
1874 to extend the syntax understood by L<SQL::Abstract>.
1875 See section L</"UNARY OPERATORS"> for details.
1881 =head2 insert($table, \@values || \%fieldvals, \%options)
1883 This is the simplest function. You simply give it a table name
1884 and either an arrayref of values or hashref of field/value pairs.
1885 It returns an SQL INSERT statement and a list of bind values.
1886 See the sections on L</"Inserting and Updating Arrays"> and
1887 L</"Inserting and Updating SQL"> for information on how to insert
1888 with those data types.
1890 The optional C<\%options> hash reference may contain additional
1891 options to generate the insert SQL. Currently supported options
1898 Takes either a scalar of raw SQL fields, or an array reference of
1899 field names, and adds on an SQL C<RETURNING> statement at the end.
1900 This allows you to return data generated by the insert statement
1901 (such as row IDs) without performing another C<SELECT> statement.
1902 Note, however, this is not part of the SQL standard and may not
1903 be supported by all database engines.
1907 =head2 update($table, \%fieldvals, \%where, \%options)
1909 This takes a table, hashref of field/value pairs, and an optional
1910 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1912 See the sections on L</"Inserting and Updating Arrays"> and
1913 L</"Inserting and Updating SQL"> for information on how to insert
1914 with those data types.
1916 The optional C<\%options> hash reference may contain additional
1917 options to generate the update SQL. Currently supported options
1924 See the C<returning> option to
1925 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1929 =head2 select($source, $fields, $where, $order)
1931 This returns a SQL SELECT statement and associated list of bind values, as
1932 specified by the arguments:
1938 Specification of the 'FROM' part of the statement.
1939 The argument can be either a plain scalar (interpreted as a table
1940 name, will be quoted), or an arrayref (interpreted as a list
1941 of table names, joined by commas, quoted), or a scalarref
1942 (literal SQL, not quoted).
1946 Specification of the list of fields to retrieve from
1948 The argument can be either an arrayref (interpreted as a list
1949 of field names, will be joined by commas and quoted), or a
1950 plain scalar (literal SQL, not quoted).
1951 Please observe that this API is not as flexible as that of
1952 the first argument C<$source>, for backwards compatibility reasons.
1956 Optional argument to specify the WHERE part of the query.
1957 The argument is most often a hashref, but can also be
1958 an arrayref or plain scalar --
1959 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1963 Optional argument to specify the ORDER BY part of the query.
1964 The argument can be a scalar, a hashref or an arrayref
1965 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1971 =head2 delete($table, \%where, \%options)
1973 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1974 It returns an SQL DELETE statement and list of bind values.
1976 The optional C<\%options> hash reference may contain additional
1977 options to generate the delete SQL. Currently supported options
1984 See the C<returning> option to
1985 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1989 =head2 where(\%where, $order)
1991 This is used to generate just the WHERE clause. For example,
1992 if you have an arbitrary data structure and know what the
1993 rest of your SQL is going to look like, but want an easy way
1994 to produce a WHERE clause, use this. It returns an SQL WHERE
1995 clause and list of bind values.
1998 =head2 values(\%data)
2000 This just returns the values from the hash C<%data>, in the same
2001 order that would be returned from any of the other above queries.
2002 Using this allows you to markedly speed up your queries if you
2003 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2005 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2007 Warning: This is an experimental method and subject to change.
2009 This returns arbitrarily generated SQL. It's a really basic shortcut.
2010 It will return two different things, depending on return context:
2012 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2013 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2015 These would return the following:
2017 # First calling form
2018 $stmt = "CREATE TABLE test (?, ?)";
2019 @bind = (field1, field2);
2021 # Second calling form
2022 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2024 Depending on what you're trying to do, it's up to you to choose the correct
2025 format. In this example, the second form is what you would want.
2029 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2033 ALTER SESSION SET nls_date_format = 'MM/YY'
2035 You get the idea. Strings get their case twiddled, but everything
2036 else remains verbatim.
2038 =head1 EXPORTABLE FUNCTIONS
2040 =head2 is_plain_value
2042 Determines if the supplied argument is a plain value as understood by this
2047 =item * The value is C<undef>
2049 =item * The value is a non-reference
2051 =item * The value is an object with stringification overloading
2053 =item * The value is of the form C<< { -value => $anything } >>
2057 On failure returns C<undef>, on success returns a B<scalar> reference
2058 to the original supplied argument.
2064 The stringification overloading detection is rather advanced: it takes
2065 into consideration not only the presence of a C<""> overload, but if that
2066 fails also checks for enabled
2067 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2068 on either C<0+> or C<bool>.
2070 Unfortunately testing in the field indicates that this
2071 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2072 but only when very large numbers of stringifying objects are involved.
2073 At the time of writing ( Sep 2014 ) there is no clear explanation of
2074 the direct cause, nor is there a manageably small test case that reliably
2075 reproduces the problem.
2077 If you encounter any of the following exceptions in B<random places within
2078 your application stack> - this module may be to blame:
2080 Operation "ne": no method found,
2081 left argument in overloaded package <something>,
2082 right argument in overloaded package <something>
2086 Stub found while resolving method "???" overloading """" in package <something>
2088 If you fall victim to the above - please attempt to reduce the problem
2089 to something that could be sent to the L<SQL::Abstract developers
2090 |DBIx::Class/GETTING HELP/SUPPORT>
2091 (either publicly or privately). As a workaround in the meantime you can
2092 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2093 value, which will most likely eliminate your problem (at the expense of
2094 not being able to properly detect exotic forms of stringification).
2096 This notice and environment variable will be removed in a future version,
2097 as soon as the underlying problem is found and a reliable workaround is
2102 =head2 is_literal_value
2104 Determines if the supplied argument is a literal value as understood by this
2109 =item * C<\$sql_string>
2111 =item * C<\[ $sql_string, @bind_values ]>
2115 On failure returns C<undef>, on success returns an B<array> reference
2116 containing the unpacked version of the supplied literal SQL and bind values.
2118 =head1 WHERE CLAUSES
2122 This module uses a variation on the idea from L<DBIx::Abstract>. It
2123 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2124 module is that things in arrays are OR'ed, and things in hashes
2127 The easiest way to explain is to show lots of examples. After
2128 each C<%where> hash shown, it is assumed you used:
2130 my($stmt, @bind) = $sql->where(\%where);
2132 However, note that the C<%where> hash can be used directly in any
2133 of the other functions as well, as described above.
2135 =head2 Key-value pairs
2137 So, let's get started. To begin, a simple hash:
2141 status => 'completed'
2144 Is converted to SQL C<key = val> statements:
2146 $stmt = "WHERE user = ? AND status = ?";
2147 @bind = ('nwiger', 'completed');
2149 One common thing I end up doing is having a list of values that
2150 a field can be in. To do this, simply specify a list inside of
2155 status => ['assigned', 'in-progress', 'pending'];
2158 This simple code will create the following:
2160 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2161 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2163 A field associated to an empty arrayref will be considered a
2164 logical false and will generate 0=1.
2166 =head2 Tests for NULL values
2168 If the value part is C<undef> then this is converted to SQL <IS NULL>
2177 $stmt = "WHERE user = ? AND status IS NULL";
2180 To test if a column IS NOT NULL:
2184 status => { '!=', undef },
2187 =head2 Specific comparison operators
2189 If you want to specify a different type of operator for your comparison,
2190 you can use a hashref for a given column:
2194 status => { '!=', 'completed' }
2197 Which would generate:
2199 $stmt = "WHERE user = ? AND status != ?";
2200 @bind = ('nwiger', 'completed');
2202 To test against multiple values, just enclose the values in an arrayref:
2204 status => { '=', ['assigned', 'in-progress', 'pending'] };
2206 Which would give you:
2208 "WHERE status = ? OR status = ? OR status = ?"
2211 The hashref can also contain multiple pairs, in which case it is expanded
2212 into an C<AND> of its elements:
2216 status => { '!=', 'completed', -not_like => 'pending%' }
2219 # Or more dynamically, like from a form
2220 $where{user} = 'nwiger';
2221 $where{status}{'!='} = 'completed';
2222 $where{status}{'-not_like'} = 'pending%';
2224 # Both generate this
2225 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2226 @bind = ('nwiger', 'completed', 'pending%');
2229 To get an OR instead, you can combine it with the arrayref idea:
2233 priority => [ { '=', 2 }, { '>', 5 } ]
2236 Which would generate:
2238 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2239 @bind = ('2', '5', 'nwiger');
2241 If you want to include literal SQL (with or without bind values), just use a
2242 scalar reference or reference to an arrayref as the value:
2245 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2246 date_expires => { '<' => \"now()" }
2249 Which would generate:
2251 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2252 @bind = ('11/26/2008');
2255 =head2 Logic and nesting operators
2257 In the example above,
2258 there is a subtle trap if you want to say something like
2259 this (notice the C<AND>):
2261 WHERE priority != ? AND priority != ?
2263 Because, in Perl you I<can't> do this:
2265 priority => { '!=' => 2, '!=' => 1 }
2267 As the second C<!=> key will obliterate the first. The solution
2268 is to use the special C<-modifier> form inside an arrayref:
2270 priority => [ -and => {'!=', 2},
2274 Normally, these would be joined by C<OR>, but the modifier tells it
2275 to use C<AND> instead. (Hint: You can use this in conjunction with the
2276 C<logic> option to C<new()> in order to change the way your queries
2277 work by default.) B<Important:> Note that the C<-modifier> goes
2278 B<INSIDE> the arrayref, as an extra first element. This will
2279 B<NOT> do what you think it might:
2281 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2283 Here is a quick list of equivalencies, since there is some overlap:
2286 status => {'!=', 'completed', 'not like', 'pending%' }
2287 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2290 status => {'=', ['assigned', 'in-progress']}
2291 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2292 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2296 =head2 Special operators: IN, BETWEEN, etc.
2298 You can also use the hashref format to compare a list of fields using the
2299 C<IN> comparison operator, by specifying the list as an arrayref:
2302 status => 'completed',
2303 reportid => { -in => [567, 2335, 2] }
2306 Which would generate:
2308 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2309 @bind = ('completed', '567', '2335', '2');
2311 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2314 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2315 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2316 'sqltrue' (by default: C<1=1>).
2318 In addition to the array you can supply a chunk of literal sql or
2319 literal sql with bind:
2322 customer => { -in => \[
2323 'SELECT cust_id FROM cust WHERE balance > ?',
2326 status => { -in => \'SELECT status_codes FROM states' },
2332 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2333 AND status IN ( SELECT status_codes FROM states )
2337 Finally, if the argument to C<-in> is not a reference, it will be
2338 treated as a single-element array.
2340 Another pair of operators is C<-between> and C<-not_between>,
2341 used with an arrayref of two values:
2345 completion_date => {
2346 -not_between => ['2002-10-01', '2003-02-06']
2352 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2354 Just like with C<-in> all plausible combinations of literal SQL
2358 start0 => { -between => [ 1, 2 ] },
2359 start1 => { -between => \["? AND ?", 1, 2] },
2360 start2 => { -between => \"lower(x) AND upper(y)" },
2361 start3 => { -between => [
2363 \["upper(?)", 'stuff' ],
2370 ( start0 BETWEEN ? AND ? )
2371 AND ( start1 BETWEEN ? AND ? )
2372 AND ( start2 BETWEEN lower(x) AND upper(y) )
2373 AND ( start3 BETWEEN lower(x) AND upper(?) )
2375 @bind = (1, 2, 1, 2, 'stuff');
2378 These are the two builtin "special operators"; but the
2379 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2381 =head2 Unary operators: bool
2383 If you wish to test against boolean columns or functions within your
2384 database you can use the C<-bool> and C<-not_bool> operators. For
2385 example to test the column C<is_user> being true and the column
2386 C<is_enabled> being false you would use:-
2390 -not_bool => 'is_enabled',
2395 WHERE is_user AND NOT is_enabled
2397 If a more complex combination is required, testing more conditions,
2398 then you should use the and/or operators:-
2403 -not_bool => { two=> { -rlike => 'bar' } },
2404 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2415 (NOT ( three = ? OR three > ? ))
2418 =head2 Nested conditions, -and/-or prefixes
2420 So far, we've seen how multiple conditions are joined with a top-level
2421 C<AND>. We can change this by putting the different conditions we want in
2422 hashes and then putting those hashes in an array. For example:
2427 status => { -like => ['pending%', 'dispatched'] },
2431 status => 'unassigned',
2435 This data structure would create the following:
2437 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2438 OR ( user = ? AND status = ? ) )";
2439 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2442 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2443 to change the logic inside:
2449 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2450 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2457 $stmt = "WHERE ( user = ?
2458 AND ( ( workhrs > ? AND geo = ? )
2459 OR ( workhrs < ? OR geo = ? ) ) )";
2460 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2462 =head3 Algebraic inconsistency, for historical reasons
2464 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2465 operator goes C<outside> of the nested structure; whereas when connecting
2466 several constraints on one column, the C<-and> operator goes
2467 C<inside> the arrayref. Here is an example combining both features:
2470 -and => [a => 1, b => 2],
2471 -or => [c => 3, d => 4],
2472 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2477 WHERE ( ( ( a = ? AND b = ? )
2478 OR ( c = ? OR d = ? )
2479 OR ( e LIKE ? AND e LIKE ? ) ) )
2481 This difference in syntax is unfortunate but must be preserved for
2482 historical reasons. So be careful: the two examples below would
2483 seem algebraically equivalent, but they are not
2486 { -like => 'foo%' },
2487 { -like => '%bar' },
2489 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2492 { col => { -like => 'foo%' } },
2493 { col => { -like => '%bar' } },
2495 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2498 =head2 Literal SQL and value type operators
2500 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2501 side" is a column name and the "right side" is a value (normally rendered as
2502 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2503 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2504 alter this behavior. There are several ways of doing so.
2508 This is a virtual operator that signals the string to its right side is an
2509 identifier (a column name) and not a value. For example to compare two
2510 columns you would write:
2513 priority => { '<', 2 },
2514 requestor => { -ident => 'submitter' },
2519 $stmt = "WHERE priority < ? AND requestor = submitter";
2522 If you are maintaining legacy code you may see a different construct as
2523 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2528 This is a virtual operator that signals that the construct to its right side
2529 is a value to be passed to DBI. This is for example necessary when you want
2530 to write a where clause against an array (for RDBMS that support such
2531 datatypes). For example:
2534 array => { -value => [1, 2, 3] }
2539 $stmt = 'WHERE array = ?';
2540 @bind = ([1, 2, 3]);
2542 Note that if you were to simply say:
2548 the result would probably not be what you wanted:
2550 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2555 Finally, sometimes only literal SQL will do. To include a random snippet
2556 of SQL verbatim, you specify it as a scalar reference. Consider this only
2557 as a last resort. Usually there is a better way. For example:
2560 priority => { '<', 2 },
2561 requestor => { -in => \'(SELECT name FROM hitmen)' },
2566 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2569 Note that in this example, you only get one bind parameter back, since
2570 the verbatim SQL is passed as part of the statement.
2574 Never use untrusted input as a literal SQL argument - this is a massive
2575 security risk (there is no way to check literal snippets for SQL
2576 injections and other nastyness). If you need to deal with untrusted input
2577 use literal SQL with placeholders as described next.
2579 =head3 Literal SQL with placeholders and bind values (subqueries)
2581 If the literal SQL to be inserted has placeholders and bind values,
2582 use a reference to an arrayref (yes this is a double reference --
2583 not so common, but perfectly legal Perl). For example, to find a date
2584 in Postgres you can use something like this:
2587 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2592 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2595 Note that you must pass the bind values in the same format as they are returned
2596 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2597 to C<columns>, you must provide the bind values in the
2598 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2599 scalar value; most commonly the column name, but you can use any scalar value
2600 (including references and blessed references), L<SQL::Abstract> will simply
2601 pass it through intact. So if C<bindtype> is set to C<columns> the above
2602 example will look like:
2605 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2608 Literal SQL is especially useful for nesting parenthesized clauses in the
2609 main SQL query. Here is a first example:
2611 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2615 bar => \["IN ($sub_stmt)" => @sub_bind],
2620 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2621 WHERE c2 < ? AND c3 LIKE ?))";
2622 @bind = (1234, 100, "foo%");
2624 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2625 are expressed in the same way. Of course the C<$sub_stmt> and
2626 its associated bind values can be generated through a former call
2629 my ($sub_stmt, @sub_bind)
2630 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2631 c3 => {-like => "foo%"}});
2634 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2637 In the examples above, the subquery was used as an operator on a column;
2638 but the same principle also applies for a clause within the main C<%where>
2639 hash, like an EXISTS subquery:
2641 my ($sub_stmt, @sub_bind)
2642 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2643 my %where = ( -and => [
2645 \["EXISTS ($sub_stmt)" => @sub_bind],
2650 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2651 WHERE c1 = ? AND c2 > t0.c0))";
2655 Observe that the condition on C<c2> in the subquery refers to
2656 column C<t0.c0> of the main query: this is I<not> a bind
2657 value, so we have to express it through a scalar ref.
2658 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2659 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2660 what we wanted here.
2662 Finally, here is an example where a subquery is used
2663 for expressing unary negation:
2665 my ($sub_stmt, @sub_bind)
2666 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2667 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2669 lname => {like => '%son%'},
2670 \["NOT ($sub_stmt)" => @sub_bind],
2675 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2676 @bind = ('%son%', 10, 20)
2678 =head3 Deprecated usage of Literal SQL
2680 Below are some examples of archaic use of literal SQL. It is shown only as
2681 reference for those who deal with legacy code. Each example has a much
2682 better, cleaner and safer alternative that users should opt for in new code.
2688 my %where = ( requestor => \'IS NOT NULL' )
2690 $stmt = "WHERE requestor IS NOT NULL"
2692 This used to be the way of generating NULL comparisons, before the handling
2693 of C<undef> got formalized. For new code please use the superior syntax as
2694 described in L</Tests for NULL values>.
2698 my %where = ( requestor => \'= submitter' )
2700 $stmt = "WHERE requestor = submitter"
2702 This used to be the only way to compare columns. Use the superior L</-ident>
2703 method for all new code. For example an identifier declared in such a way
2704 will be properly quoted if L</quote_char> is properly set, while the legacy
2705 form will remain as supplied.
2709 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2711 $stmt = "WHERE completed > ? AND is_ready"
2712 @bind = ('2012-12-21')
2714 Using an empty string literal used to be the only way to express a boolean.
2715 For all new code please use the much more readable
2716 L<-bool|/Unary operators: bool> operator.
2722 These pages could go on for a while, since the nesting of the data
2723 structures this module can handle are pretty much unlimited (the
2724 module implements the C<WHERE> expansion as a recursive function
2725 internally). Your best bet is to "play around" with the module a
2726 little to see how the data structures behave, and choose the best
2727 format for your data based on that.
2729 And of course, all the values above will probably be replaced with
2730 variables gotten from forms or the command line. After all, if you
2731 knew everything ahead of time, you wouldn't have to worry about
2732 dynamically-generating SQL and could just hardwire it into your
2735 =head1 ORDER BY CLAUSES
2737 Some functions take an order by clause. This can either be a scalar (just a
2738 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2739 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2742 Given | Will Generate
2743 ---------------------------------------------------------------
2745 'colA' | ORDER BY colA
2747 [qw/colA colB/] | ORDER BY colA, colB
2749 {-asc => 'colA'} | ORDER BY colA ASC
2751 {-desc => 'colB'} | ORDER BY colB DESC
2753 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2755 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2757 \'colA DESC' | ORDER BY colA DESC
2759 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2760 | /* ...with $x bound to ? */
2763 { -asc => 'colA' }, | colA ASC,
2764 { -desc => [qw/colB/] }, | colB DESC,
2765 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2766 \'colE DESC', | colE DESC,
2767 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2768 ] | /* ...with $x bound to ? */
2769 ===============================================================
2773 =head1 SPECIAL OPERATORS
2775 my $sqlmaker = SQL::Abstract->new(special_ops => [
2779 my ($self, $field, $op, $arg) = @_;
2785 handler => 'method_name',
2789 A "special operator" is a SQL syntactic clause that can be
2790 applied to a field, instead of a usual binary operator.
2793 WHERE field IN (?, ?, ?)
2794 WHERE field BETWEEN ? AND ?
2795 WHERE MATCH(field) AGAINST (?, ?)
2797 Special operators IN and BETWEEN are fairly standard and therefore
2798 are builtin within C<SQL::Abstract> (as the overridable methods
2799 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2800 like the MATCH .. AGAINST example above which is specific to MySQL,
2801 you can write your own operator handlers - supply a C<special_ops>
2802 argument to the C<new> method. That argument takes an arrayref of
2803 operator definitions; each operator definition is a hashref with two
2810 the regular expression to match the operator
2814 Either a coderef or a plain scalar method name. In both cases
2815 the expected return is C<< ($sql, @bind) >>.
2817 When supplied with a method name, it is simply called on the
2818 L<SQL::Abstract> object as:
2820 $self->$method_name($field, $op, $arg)
2824 $field is the LHS of the operator
2825 $op is the part that matched the handler regex
2828 When supplied with a coderef, it is called as:
2830 $coderef->($self, $field, $op, $arg)
2835 For example, here is an implementation
2836 of the MATCH .. AGAINST syntax for MySQL
2838 my $sqlmaker = SQL::Abstract->new(special_ops => [
2840 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2841 {regex => qr/^match$/i,
2843 my ($self, $field, $op, $arg) = @_;
2844 $arg = [$arg] if not ref $arg;
2845 my $label = $self->_quote($field);
2846 my ($placeholder) = $self->_convert('?');
2847 my $placeholders = join ", ", (($placeholder) x @$arg);
2848 my $sql = $self->_sqlcase('match') . " ($label) "
2849 . $self->_sqlcase('against') . " ($placeholders) ";
2850 my @bind = $self->_bindtype($field, @$arg);
2851 return ($sql, @bind);
2858 =head1 UNARY OPERATORS
2860 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2864 my ($self, $op, $arg) = @_;
2870 handler => 'method_name',
2874 A "unary operator" is a SQL syntactic clause that can be
2875 applied to a field - the operator goes before the field
2877 You can write your own operator handlers - supply a C<unary_ops>
2878 argument to the C<new> method. That argument takes an arrayref of
2879 operator definitions; each operator definition is a hashref with two
2886 the regular expression to match the operator
2890 Either a coderef or a plain scalar method name. In both cases
2891 the expected return is C<< $sql >>.
2893 When supplied with a method name, it is simply called on the
2894 L<SQL::Abstract> object as:
2896 $self->$method_name($op, $arg)
2900 $op is the part that matched the handler regex
2901 $arg is the RHS or argument of the operator
2903 When supplied with a coderef, it is called as:
2905 $coderef->($self, $op, $arg)
2913 Thanks to some benchmarking by Mark Stosberg, it turns out that
2914 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2915 I must admit this wasn't an intentional design issue, but it's a
2916 byproduct of the fact that you get to control your C<DBI> handles
2919 To maximize performance, use a code snippet like the following:
2921 # prepare a statement handle using the first row
2922 # and then reuse it for the rest of the rows
2924 for my $href (@array_of_hashrefs) {
2925 $stmt ||= $sql->insert('table', $href);
2926 $sth ||= $dbh->prepare($stmt);
2927 $sth->execute($sql->values($href));
2930 The reason this works is because the keys in your C<$href> are sorted
2931 internally by B<SQL::Abstract>. Thus, as long as your data retains
2932 the same structure, you only have to generate the SQL the first time
2933 around. On subsequent queries, simply use the C<values> function provided
2934 by this module to return your values in the correct order.
2936 However this depends on the values having the same type - if, for
2937 example, the values of a where clause may either have values
2938 (resulting in sql of the form C<column = ?> with a single bind
2939 value), or alternatively the values might be C<undef> (resulting in
2940 sql of the form C<column IS NULL> with no bind value) then the
2941 caching technique suggested will not work.
2945 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2946 really like this part (I do, at least). Building up a complex query
2947 can be as simple as the following:
2954 use CGI::FormBuilder;
2957 my $form = CGI::FormBuilder->new(...);
2958 my $sql = SQL::Abstract->new;
2960 if ($form->submitted) {
2961 my $field = $form->field;
2962 my $id = delete $field->{id};
2963 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2966 Of course, you would still have to connect using C<DBI> to run the
2967 query, but the point is that if you make your form look like your
2968 table, the actual query script can be extremely simplistic.
2970 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2971 a fast interface to returning and formatting data. I frequently
2972 use these three modules together to write complex database query
2973 apps in under 50 lines.
2975 =head1 HOW TO CONTRIBUTE
2977 Contributions are always welcome, in all usable forms (we especially
2978 welcome documentation improvements). The delivery methods include git-
2979 or unified-diff formatted patches, GitHub pull requests, or plain bug
2980 reports either via RT or the Mailing list. Contributors are generally
2981 granted full access to the official repository after their first several
2982 patches pass successful review.
2984 This project is maintained in a git repository. The code and related tools are
2985 accessible at the following locations:
2989 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2991 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2993 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2995 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3001 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3002 Great care has been taken to preserve the I<published> behavior
3003 documented in previous versions in the 1.* family; however,
3004 some features that were previously undocumented, or behaved
3005 differently from the documentation, had to be changed in order
3006 to clarify the semantics. Hence, client code that was relying
3007 on some dark areas of C<SQL::Abstract> v1.*
3008 B<might behave differently> in v1.50.
3010 The main changes are:
3016 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3020 support for the { operator => \"..." } construct (to embed literal SQL)
3024 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3028 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3032 defensive programming: check arguments
3036 fixed bug with global logic, which was previously implemented
3037 through global variables yielding side-effects. Prior versions would
3038 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3039 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3040 Now this is interpreted
3041 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3046 fixed semantics of _bindtype on array args
3050 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3051 we just avoid shifting arrays within that tree.
3055 dropped the C<_modlogic> function
3059 =head1 ACKNOWLEDGEMENTS
3061 There are a number of individuals that have really helped out with
3062 this module. Unfortunately, most of them submitted bugs via CPAN
3063 so I have no idea who they are! But the people I do know are:
3065 Ash Berlin (order_by hash term support)
3066 Matt Trout (DBIx::Class support)
3067 Mark Stosberg (benchmarking)
3068 Chas Owens (initial "IN" operator support)
3069 Philip Collins (per-field SQL functions)
3070 Eric Kolve (hashref "AND" support)
3071 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3072 Dan Kubb (support for "quote_char" and "name_sep")
3073 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3074 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3075 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3076 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3077 Oliver Charles (support for "RETURNING" after "INSERT")
3083 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3087 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3089 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3091 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3092 While not an official support venue, C<DBIx::Class> makes heavy use of
3093 C<SQL::Abstract>, and as such list members there are very familiar with
3094 how to create queries.
3098 This module is free software; you may copy this under the same
3099 terms as perl itself (either the GNU General Public License or
3100 the Artistic License)