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/
187 $opt{node_types} = +{
188 map +("-$_" => '_render_'.$_),
189 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_expr(
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_expr(
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_expr(
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_expr(
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, $logic, $default_scalar_to) = @_;
508 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
509 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
510 return undef unless defined($expr);
511 if (ref($expr) eq 'HASH') {
512 if (keys %$expr > 1) {
516 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
520 return undef unless keys %$expr;
521 return $self->_expand_expr_hashpair(%$expr, $logic);
523 if (ref($expr) eq 'ARRAY') {
524 my $logic = lc($logic || $self->{logic});
525 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
528 (ref($_) eq 'ARRAY' and @$_)
529 or (ref($_) eq 'HASH' and %$_)
535 while (my ($el) = splice @expr, 0, 1) {
536 puke "Supplying an empty left hand side argument is not supported in array-pairs"
537 unless defined($el) and length($el);
538 my $elref = ref($el);
540 local $Expand_Depth = 0;
541 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
542 } elsif ($elref eq 'ARRAY') {
543 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
544 } elsif (my $l = is_literal_value($el)) {
545 push @res, { -literal => $l };
546 } elsif ($elref eq 'HASH') {
547 local $Expand_Depth = 0;
548 push @res, grep defined, $self->_expand_expr($el) if %$el;
553 return { -op => [ $logic, @res ] };
555 if (my $literal = is_literal_value($expr)) {
556 return +{ -literal => $literal };
558 if (!ref($expr) or Scalar::Util::blessed($expr)) {
559 if (my $d = $Default_Scalar_To) {
560 return $self->_expand_expr({ $d => $expr });
562 if (my $m = our $Cur_Col_Meta) {
563 return +{ -bind => [ $m, $expr ] };
565 return +{ -bind => [ undef, $expr ] };
570 sub _expand_expr_hashpair {
571 my ($self, $k, $v, $logic) = @_;
572 unless (defined($k) and length($k)) {
573 if (defined($k) and my $literal = is_literal_value($v)) {
574 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
575 return { -literal => $literal };
577 puke "Supplying an empty left hand side argument is not supported";
580 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
581 if ($k =~ s/ [_\s]? \d+ $//x ) {
582 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
583 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
586 # DBIx::Class requires a nest warning to be emitted once but the private
587 # method it overrode to do so no longer exists
588 if ($self->{is_dbic_sqlmaker}) {
589 unless (our $Nest_Warned) {
591 "-nest in search conditions is deprecated, you most probably wanted:\n"
592 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
597 return $self->_expand_expr($v);
601 return $self->_expand_expr($v);
603 puke "-bool => undef not supported" unless defined($v);
604 return { -ident => $v };
607 return { -op => [ 'not', $self->_expand_expr($v) ] };
609 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
612 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
615 if (my ($logic) = $k =~ /^-(and|or)$/i) {
616 if (ref($v) eq 'HASH') {
617 return $self->_expand_expr($v, $logic);
619 if (ref($v) eq 'ARRAY') {
620 return $self->_expand_expr($v, $logic);
625 $op =~ s/^-// if length($op) > 1;
627 # top level special ops are illegal in general
628 # note that, arguably, if it makes no sense at top level, it also
629 # makes no sense on the other side of an = sign or similar but DBIC
630 # gets disappointingly upset if I disallow it
632 (our $Expand_Depth) == 1
633 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
635 puke "Illegal use of top-level '-$op'"
637 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
638 return { -op => [ $op, $v ] };
641 if ($k eq '-value') {
642 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
644 if (my $custom = $self->{expand_unary}{$k}) {
645 return $self->$custom($v);
647 if ($self->{node_types}{$k}) {
653 and (keys %$v)[0] =~ /^-/
655 my ($func) = $k =~ /^-(.*)$/;
656 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
657 return +{ -op => [ $func, $self->_expand_expr($v) ] };
659 return +{ -func => [ $func, $self->_expand_expr($v) ] };
661 if (!ref($v) or is_literal_value($v)) {
662 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
669 and exists $v->{-value}
670 and not defined $v->{-value}
673 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
675 if (!ref($v) or Scalar::Util::blessed($v)) {
676 my $d = our $Default_Scalar_To;
681 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
685 if (ref($v) eq 'HASH') {
689 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
693 return undef unless keys %$v;
697 $self->_assert_pass_injection_guard($vk);
698 if ($vk =~ s/ [_\s]? \d+ $//x ) {
699 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
700 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
702 if ($vk =~ /^(?:not[ _])?between$/) {
703 local our $Cur_Col_Meta = $k;
704 my @rhs = map $self->_expand_expr($_),
705 ref($vv) eq 'ARRAY' ? @$vv : $vv;
707 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
709 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
711 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
714 join(' ', split '_', $vk),
719 if ($vk =~ /^(?:not[ _])?in$/) {
720 if (my $literal = is_literal_value($vv)) {
721 my ($sql, @bind) = @$literal;
722 my $opened_sql = $self->_open_outer_paren($sql);
724 $vk, { -ident => $k },
725 [ { -literal => [ $opened_sql, @bind ] } ]
729 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
730 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
731 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
732 . 'will emit the logically correct SQL instead of raising this exception)'
734 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
736 my @rhs = map $self->_expand_expr($_),
737 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
738 map { defined($_) ? $_: puke($undef_err) }
739 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
740 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
743 join(' ', split '_', $vk),
748 if ($vk eq 'ident') {
749 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
750 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
758 if ($vk eq 'value') {
759 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
763 { -bind => [ $k, $vv ] }
766 if ($vk =~ /^is(?:[ _]not)?$/) {
767 puke "$vk can only take undef as argument"
771 and exists($vv->{-value})
772 and !defined($vv->{-value})
775 return +{ -op => [ $vk.' null', { -ident => $k } ] };
777 if ($vk =~ /^(and|or)$/) {
778 if (ref($vv) eq 'HASH') {
781 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
786 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
787 return { -op => [ $vk, { -ident => $k }, $vv ] };
789 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
793 { -op => [ $vk, $vv ] }
796 if (ref($vv) eq 'ARRAY') {
797 my ($logic, @values) = (
798 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
803 $vk =~ $self->{inequality_op}
804 or join(' ', split '_', $vk) =~ $self->{not_like_op}
806 if (lc($logic) eq '-or' and @values > 1) {
807 my $op = uc join ' ', split '_', $vk;
808 belch "A multi-element arrayref as an argument to the inequality op '$op' "
809 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
810 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
815 # try to DWIM on equality operators
816 my $op = join ' ', split '_', $vk;
818 $op =~ $self->{equality_op} ? $self->sqlfalse
819 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
820 : $op =~ $self->{inequality_op} ? $self->sqltrue
821 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
822 : puke "operator '$op' applied on an empty array (field '$k')";
826 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
834 and exists $vv->{-value}
835 and not defined $vv->{-value}
838 my $op = join ' ', split '_', $vk;
840 $op =~ /^not$/i ? 'is not' # legacy
841 : $op =~ $self->{equality_op} ? 'is'
842 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
843 : $op =~ $self->{inequality_op} ? 'is not'
844 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
845 : puke "unexpected operator '$op' with undef operand";
846 return +{ -op => [ $is.' null', { -ident => $k } ] };
848 local our $Cur_Col_Meta = $k;
852 $self->_expand_expr($vv)
855 if (ref($v) eq 'ARRAY') {
856 return $self->sqlfalse unless @$v;
857 $self->_debug("ARRAY($k) means distribute over elements");
859 $v->[0] =~ /^-((?:and|or))$/i
860 ? ($v = [ @{$v}[1..$#$v] ], $1)
861 : ($self->{logic} || 'or')
865 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
868 if (my $literal = is_literal_value($v)) {
870 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
873 my ($sql, @bind) = @$literal;
874 if ($self->{bindtype} eq 'columns') {
876 $self->_assert_bindval_matches_bindtype($_);
879 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
885 my ($self, $expr) = @_;
886 my ($k, $v, @rest) = %$expr;
888 if (my $meth = $self->{node_types}{$k}) {
889 return $self->$meth($v);
891 die "notreached: $k";
895 my ($self, $where, $logic) = @_;
897 # Special case: top level simple string treated as literal
899 my $where_exp = (ref($where)
900 ? $self->_expand_expr($where, $logic)
901 : { -literal => [ $where ] });
903 # dispatch expanded expression
905 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
906 # DBIx::Class used to call _recurse_where in scalar context
907 # something else might too...
909 return ($sql, @bind);
912 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
918 my ($self, $ident) = @_;
920 return $self->_convert($self->_quote($ident));
923 my %unop_postfix = map +($_ => 1),
924 'is null', 'is not null',
932 my ($self, $args) = @_;
933 my ($left, $low, $high) = @$args;
934 my ($rhsql, @rhbind) = do {
936 puke "Single arg to between must be a literal"
937 unless $low->{-literal};
940 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
941 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
942 @{$l}[1..$#$l], @{$h}[1..$#$h])
945 my ($lhsql, @lhbind) = $self->_render_expr($left);
947 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
951 }), 'between', 'not between'),
955 my ($self, $args) = @_;
956 my ($lhs, $rhs) = @$args;
959 my ($sql, @bind) = $self->_render_expr($_);
960 push @in_bind, @bind;
963 my ($lhsql, @lbind) = $self->_render_expr($lhs);
965 $lhsql.' '.$self->_sqlcase($op).' ( '
976 my ($op, @args) = @$v;
977 $op =~ s/^-// if length($op) > 1;
979 if (my $h = $special{$op}) {
980 return $self->$h(\@args);
982 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
983 if ($us and @args > 1) {
984 puke "Special op '${op}' requires first value to be identifier"
985 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
986 local our $Expand_Depth = 1;
987 return $self->${\($us->{handler})}($k, $op, $args[1]);
989 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
990 return $self->${\($us->{handler})}($op, $args[0]);
992 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
993 if (@args == 1 and $op !~ /^(and|or)$/) {
994 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
995 my $op_sql = $self->_sqlcase($final_op);
997 $unop_postfix{lc($final_op)}
998 ? "${expr_sql} ${op_sql}"
999 : "${op_sql} ${expr_sql}"
1001 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1003 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @args;
1004 return '' unless @parts;
1005 my $is_andor = !!($op =~ /^(and|or)$/);
1006 return @{$parts[0]} if $is_andor and @parts == 1;
1007 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1008 ' '.$self->_sqlcase($final_op).' ',
1013 map @{$_}[1..$#$_], @parts
1020 my ($self, $list) = @_;
1021 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @$list;
1022 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1026 my ($self, $rest) = @_;
1027 my ($func, @args) = @$rest;
1031 push @arg_sql, shift @x;
1033 } map [ $self->_render_expr($_) ], @args;
1034 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1038 my ($self, $bind) = @_;
1039 return ($self->_convert('?'), $self->_bindtype(@$bind));
1042 sub _render_literal {
1043 my ($self, $literal) = @_;
1044 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1048 # Some databases (SQLite) treat col IN (1, 2) different from
1049 # col IN ( (1, 2) ). Use this to strip all outer parens while
1050 # adding them back in the corresponding method
1051 sub _open_outer_paren {
1052 my ($self, $sql) = @_;
1054 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1056 # there are closing parens inside, need the heavy duty machinery
1057 # to reevaluate the extraction starting from $sql (full reevaluation)
1058 if ($inner =~ /\)/) {
1059 require Text::Balanced;
1061 my (undef, $remainder) = do {
1062 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1064 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1067 # the entire expression needs to be a balanced bracketed thing
1068 # (after an extract no remainder sans trailing space)
1069 last if defined $remainder and $remainder =~ /\S/;
1079 #======================================================================
1081 #======================================================================
1083 sub _expand_order_by {
1084 my ($self, $arg) = @_;
1086 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1088 my $expander = sub {
1089 my ($self, $dir, $expr) = @_;
1090 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1091 foreach my $arg (@to_expand) {
1095 and grep /^-(asc|desc)$/, keys %$arg
1097 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1100 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1101 map $self->_expand_expr($_, undef, -ident),
1102 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1103 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1106 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1107 sub { shift->$expander(asc => @_) },
1108 sub { shift->$expander(desc => @_) },
1111 return $self->$expander(undef, $arg);
1115 my ($self, $arg) = @_;
1117 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1119 my ($sql, @bind) = $self->_render_expr($expanded);
1121 return '' unless length($sql);
1123 my $final_sql = $self->_sqlcase(' order by ').$sql;
1125 return wantarray ? ($final_sql, @bind) : $final_sql;
1128 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1130 sub _order_by_chunks {
1131 my ($self, $arg) = @_;
1133 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1135 return $self->_chunkify_order_by($expanded);
1138 sub _chunkify_order_by {
1139 my ($self, $expanded) = @_;
1141 return grep length, $self->_render_expr($expanded)
1142 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1145 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1146 return map $self->_chunkify_order_by($_), @$l;
1148 return [ $self->_render_expr($_) ];
1152 #======================================================================
1153 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1154 #======================================================================
1159 ($self->_render_expr(
1160 $self->_expand_maybe_list_expr($from, undef, -ident)
1165 #======================================================================
1167 #======================================================================
1169 sub _expand_maybe_list_expr {
1170 my ($self, $expr, $logic, $default) = @_;
1172 if (ref($expr) eq 'ARRAY') {
1174 map $self->_expand_expr($_, $logic, $default), @$expr
1181 return $self->_expand_expr($e, $logic, $default);
1184 # highly optimized, as it's called way too often
1186 # my ($self, $label) = @_;
1188 return '' unless defined $_[1];
1189 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1190 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1192 unless ($_[0]->{quote_char}) {
1193 if (ref($_[1]) eq 'ARRAY') {
1194 return join($_[0]->{name_sep}||'.', @{$_[1]});
1196 $_[0]->_assert_pass_injection_guard($_[1]);
1201 my $qref = ref $_[0]->{quote_char};
1203 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1204 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1205 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1207 my $esc = $_[0]->{escape_char} || $r;
1209 # parts containing * are naturally unquoted
1211 $_[0]->{name_sep}||'',
1215 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1217 (ref($_[1]) eq 'ARRAY'
1221 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1229 # Conversion, if applicable
1231 #my ($self, $arg) = @_;
1232 if ($_[0]->{convert_where}) {
1233 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1240 #my ($self, $col, @vals) = @_;
1241 # called often - tighten code
1242 return $_[0]->{bindtype} eq 'columns'
1243 ? map {[$_[1], $_]} @_[2 .. $#_]
1248 # Dies if any element of @bind is not in [colname => value] format
1249 # if bindtype is 'columns'.
1250 sub _assert_bindval_matches_bindtype {
1251 # my ($self, @bind) = @_;
1253 if ($self->{bindtype} eq 'columns') {
1255 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1256 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1262 sub _join_sql_clauses {
1263 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1265 if (@$clauses_aref > 1) {
1266 my $join = " " . $self->_sqlcase($logic) . " ";
1267 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1268 return ($sql, @$bind_aref);
1270 elsif (@$clauses_aref) {
1271 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1274 return (); # if no SQL, ignore @$bind_aref
1279 # Fix SQL case, if so requested
1281 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1282 # don't touch the argument ... crooked logic, but let's not change it!
1283 return $_[0]->{case} ? $_[1] : uc($_[1]);
1287 #======================================================================
1288 # DISPATCHING FROM REFKIND
1289 #======================================================================
1292 my ($self, $data) = @_;
1294 return 'UNDEF' unless defined $data;
1296 # blessed objects are treated like scalars
1297 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1299 return 'SCALAR' unless $ref;
1302 while ($ref eq 'REF') {
1304 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1308 return ($ref||'SCALAR') . ('REF' x $n_steps);
1312 my ($self, $data) = @_;
1313 my @try = ($self->_refkind($data));
1314 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1315 push @try, 'FALLBACK';
1319 sub _METHOD_FOR_refkind {
1320 my ($self, $meth_prefix, $data) = @_;
1323 for (@{$self->_try_refkind($data)}) {
1324 $method = $self->can($meth_prefix."_".$_)
1328 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1332 sub _SWITCH_refkind {
1333 my ($self, $data, $dispatch_table) = @_;
1336 for (@{$self->_try_refkind($data)}) {
1337 $coderef = $dispatch_table->{$_}
1341 puke "no dispatch entry for ".$self->_refkind($data)
1350 #======================================================================
1351 # VALUES, GENERATE, AUTOLOAD
1352 #======================================================================
1354 # LDNOTE: original code from nwiger, didn't touch code in that section
1355 # I feel the AUTOLOAD stuff should not be the default, it should
1356 # only be activated on explicit demand by user.
1360 my $data = shift || return;
1361 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1362 unless ref $data eq 'HASH';
1365 foreach my $k (sort keys %$data) {
1366 my $v = $data->{$k};
1367 $self->_SWITCH_refkind($v, {
1369 if ($self->{array_datatypes}) { # array datatype
1370 push @all_bind, $self->_bindtype($k, $v);
1372 else { # literal SQL with bind
1373 my ($sql, @bind) = @$v;
1374 $self->_assert_bindval_matches_bindtype(@bind);
1375 push @all_bind, @bind;
1378 ARRAYREFREF => sub { # literal SQL with bind
1379 my ($sql, @bind) = @${$v};
1380 $self->_assert_bindval_matches_bindtype(@bind);
1381 push @all_bind, @bind;
1383 SCALARREF => sub { # literal SQL without bind
1385 SCALAR_or_UNDEF => sub {
1386 push @all_bind, $self->_bindtype($k, $v);
1397 my(@sql, @sqlq, @sqlv);
1401 if ($ref eq 'HASH') {
1402 for my $k (sort keys %$_) {
1405 my $label = $self->_quote($k);
1406 if ($r eq 'ARRAY') {
1407 # literal SQL with bind
1408 my ($sql, @bind) = @$v;
1409 $self->_assert_bindval_matches_bindtype(@bind);
1410 push @sqlq, "$label = $sql";
1412 } elsif ($r eq 'SCALAR') {
1413 # literal SQL without bind
1414 push @sqlq, "$label = $$v";
1416 push @sqlq, "$label = ?";
1417 push @sqlv, $self->_bindtype($k, $v);
1420 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1421 } elsif ($ref eq 'ARRAY') {
1422 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1425 if ($r eq 'ARRAY') { # literal SQL with bind
1426 my ($sql, @bind) = @$v;
1427 $self->_assert_bindval_matches_bindtype(@bind);
1430 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1431 # embedded literal SQL
1438 push @sql, '(' . join(', ', @sqlq) . ')';
1439 } elsif ($ref eq 'SCALAR') {
1443 # strings get case twiddled
1444 push @sql, $self->_sqlcase($_);
1448 my $sql = join ' ', @sql;
1450 # this is pretty tricky
1451 # if ask for an array, return ($stmt, @bind)
1452 # otherwise, s/?/shift @sqlv/ to put it inline
1454 return ($sql, @sqlv);
1456 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1457 ref $d ? $d->[1] : $d/e;
1466 # This allows us to check for a local, then _form, attr
1468 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1469 return $self->generate($name, @_);
1480 SQL::Abstract - Generate SQL from Perl data structures
1486 my $sql = SQL::Abstract->new;
1488 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1490 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1492 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1494 my($stmt, @bind) = $sql->delete($table, \%where);
1496 # Then, use these in your DBI statements
1497 my $sth = $dbh->prepare($stmt);
1498 $sth->execute(@bind);
1500 # Just generate the WHERE clause
1501 my($stmt, @bind) = $sql->where(\%where, $order);
1503 # Return values in the same order, for hashed queries
1504 # See PERFORMANCE section for more details
1505 my @bind = $sql->values(\%fieldvals);
1509 This module was inspired by the excellent L<DBIx::Abstract>.
1510 However, in using that module I found that what I really wanted
1511 to do was generate SQL, but still retain complete control over my
1512 statement handles and use the DBI interface. So, I set out to
1513 create an abstract SQL generation module.
1515 While based on the concepts used by L<DBIx::Abstract>, there are
1516 several important differences, especially when it comes to WHERE
1517 clauses. I have modified the concepts used to make the SQL easier
1518 to generate from Perl data structures and, IMO, more intuitive.
1519 The underlying idea is for this module to do what you mean, based
1520 on the data structures you provide it. The big advantage is that
1521 you don't have to modify your code every time your data changes,
1522 as this module figures it out.
1524 To begin with, an SQL INSERT is as easy as just specifying a hash
1525 of C<key=value> pairs:
1528 name => 'Jimbo Bobson',
1529 phone => '123-456-7890',
1530 address => '42 Sister Lane',
1531 city => 'St. Louis',
1532 state => 'Louisiana',
1535 The SQL can then be generated with this:
1537 my($stmt, @bind) = $sql->insert('people', \%data);
1539 Which would give you something like this:
1541 $stmt = "INSERT INTO people
1542 (address, city, name, phone, state)
1543 VALUES (?, ?, ?, ?, ?)";
1544 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1545 '123-456-7890', 'Louisiana');
1547 These are then used directly in your DBI code:
1549 my $sth = $dbh->prepare($stmt);
1550 $sth->execute(@bind);
1552 =head2 Inserting and Updating Arrays
1554 If your database has array types (like for example Postgres),
1555 activate the special option C<< array_datatypes => 1 >>
1556 when creating the C<SQL::Abstract> object.
1557 Then you may use an arrayref to insert and update database array types:
1559 my $sql = SQL::Abstract->new(array_datatypes => 1);
1561 planets => [qw/Mercury Venus Earth Mars/]
1564 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1568 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1570 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1573 =head2 Inserting and Updating SQL
1575 In order to apply SQL functions to elements of your C<%data> you may
1576 specify a reference to an arrayref for the given hash value. For example,
1577 if you need to execute the Oracle C<to_date> function on a value, you can
1578 say something like this:
1582 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1585 The first value in the array is the actual SQL. Any other values are
1586 optional and would be included in the bind values array. This gives
1589 my($stmt, @bind) = $sql->insert('people', \%data);
1591 $stmt = "INSERT INTO people (name, date_entered)
1592 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1593 @bind = ('Bill', '03/02/2003');
1595 An UPDATE is just as easy, all you change is the name of the function:
1597 my($stmt, @bind) = $sql->update('people', \%data);
1599 Notice that your C<%data> isn't touched; the module will generate
1600 the appropriately quirky SQL for you automatically. Usually you'll
1601 want to specify a WHERE clause for your UPDATE, though, which is
1602 where handling C<%where> hashes comes in handy...
1604 =head2 Complex where statements
1606 This module can generate pretty complicated WHERE statements
1607 easily. For example, simple C<key=value> pairs are taken to mean
1608 equality, and if you want to see if a field is within a set
1609 of values, you can use an arrayref. Let's say we wanted to
1610 SELECT some data based on this criteria:
1613 requestor => 'inna',
1614 worker => ['nwiger', 'rcwe', 'sfz'],
1615 status => { '!=', 'completed' }
1618 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1620 The above would give you something like this:
1622 $stmt = "SELECT * FROM tickets WHERE
1623 ( requestor = ? ) AND ( status != ? )
1624 AND ( worker = ? OR worker = ? OR worker = ? )";
1625 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1627 Which you could then use in DBI code like so:
1629 my $sth = $dbh->prepare($stmt);
1630 $sth->execute(@bind);
1636 The methods are simple. There's one for every major SQL operation,
1637 and a constructor you use first. The arguments are specified in a
1638 similar order for each method (table, then fields, then a where
1639 clause) to try and simplify things.
1641 =head2 new(option => 'value')
1643 The C<new()> function takes a list of options and values, and returns
1644 a new B<SQL::Abstract> object which can then be used to generate SQL
1645 through the methods below. The options accepted are:
1651 If set to 'lower', then SQL will be generated in all lowercase. By
1652 default SQL is generated in "textbook" case meaning something like:
1654 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1656 Any setting other than 'lower' is ignored.
1660 This determines what the default comparison operator is. By default
1661 it is C<=>, meaning that a hash like this:
1663 %where = (name => 'nwiger', email => 'nate@wiger.org');
1665 Will generate SQL like this:
1667 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1669 However, you may want loose comparisons by default, so if you set
1670 C<cmp> to C<like> you would get SQL such as:
1672 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1674 You can also override the comparison on an individual basis - see
1675 the huge section on L</"WHERE CLAUSES"> at the bottom.
1677 =item sqltrue, sqlfalse
1679 Expressions for inserting boolean values within SQL statements.
1680 By default these are C<1=1> and C<1=0>. They are used
1681 by the special operators C<-in> and C<-not_in> for generating
1682 correct SQL even when the argument is an empty array (see below).
1686 This determines the default logical operator for multiple WHERE
1687 statements in arrays or hashes. If absent, the default logic is "or"
1688 for arrays, and "and" for hashes. This means that a WHERE
1692 event_date => {'>=', '2/13/99'},
1693 event_date => {'<=', '4/24/03'},
1696 will generate SQL like this:
1698 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1700 This is probably not what you want given this query, though (look
1701 at the dates). To change the "OR" to an "AND", simply specify:
1703 my $sql = SQL::Abstract->new(logic => 'and');
1705 Which will change the above C<WHERE> to:
1707 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1709 The logic can also be changed locally by inserting
1710 a modifier in front of an arrayref:
1712 @where = (-and => [event_date => {'>=', '2/13/99'},
1713 event_date => {'<=', '4/24/03'} ]);
1715 See the L</"WHERE CLAUSES"> section for explanations.
1719 This will automatically convert comparisons using the specified SQL
1720 function for both column and value. This is mostly used with an argument
1721 of C<upper> or C<lower>, so that the SQL will have the effect of
1722 case-insensitive "searches". For example, this:
1724 $sql = SQL::Abstract->new(convert => 'upper');
1725 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1727 Will turn out the following SQL:
1729 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1731 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1732 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1733 not validate this option; it will just pass through what you specify verbatim).
1737 This is a kludge because many databases suck. For example, you can't
1738 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1739 Instead, you have to use C<bind_param()>:
1741 $sth->bind_param(1, 'reg data');
1742 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1744 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1745 which loses track of which field each slot refers to. Fear not.
1747 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1748 Currently, you can specify either C<normal> (default) or C<columns>. If you
1749 specify C<columns>, you will get an array that looks like this:
1751 my $sql = SQL::Abstract->new(bindtype => 'columns');
1752 my($stmt, @bind) = $sql->insert(...);
1755 [ 'column1', 'value1' ],
1756 [ 'column2', 'value2' ],
1757 [ 'column3', 'value3' ],
1760 You can then iterate through this manually, using DBI's C<bind_param()>.
1762 $sth->prepare($stmt);
1765 my($col, $data) = @$_;
1766 if ($col eq 'details' || $col eq 'comments') {
1767 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1768 } elsif ($col eq 'image') {
1769 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1771 $sth->bind_param($i, $data);
1775 $sth->execute; # execute without @bind now
1777 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1778 Basically, the advantage is still that you don't have to care which fields
1779 are or are not included. You could wrap that above C<for> loop in a simple
1780 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1781 get a layer of abstraction over manual SQL specification.
1783 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1784 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1785 will expect the bind values in this format.
1789 This is the character that a table or column name will be quoted
1790 with. By default this is an empty string, but you could set it to
1791 the character C<`>, to generate SQL like this:
1793 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1795 Alternatively, you can supply an array ref of two items, the first being the left
1796 hand quote character, and the second the right hand quote character. For
1797 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1798 that generates SQL like this:
1800 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1802 Quoting is useful if you have tables or columns names that are reserved
1803 words in your database's SQL dialect.
1807 This is the character that will be used to escape L</quote_char>s appearing
1808 in an identifier before it has been quoted.
1810 The parameter default in case of a single L</quote_char> character is the quote
1813 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1814 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1815 of the B<opening (left)> L</quote_char> within the identifier are currently left
1816 untouched. The default for opening-closing-style quotes may change in future
1817 versions, thus you are B<strongly encouraged> to specify the escape character
1822 This is the character that separates a table and column name. It is
1823 necessary to specify this when the C<quote_char> option is selected,
1824 so that tables and column names can be individually quoted like this:
1826 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1828 =item injection_guard
1830 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1831 column name specified in a query structure. This is a safety mechanism to avoid
1832 injection attacks when mishandling user input e.g.:
1834 my %condition_as_column_value_pairs = get_values_from_user();
1835 $sqla->select( ... , \%condition_as_column_value_pairs );
1837 If the expression matches an exception is thrown. Note that literal SQL
1838 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1840 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1842 =item array_datatypes
1844 When this option is true, arrayrefs in INSERT or UPDATE are
1845 interpreted as array datatypes and are passed directly
1847 When this option is false, arrayrefs are interpreted
1848 as literal SQL, just like refs to arrayrefs
1849 (but this behavior is for backwards compatibility; when writing
1850 new queries, use the "reference to arrayref" syntax
1856 Takes a reference to a list of "special operators"
1857 to extend the syntax understood by L<SQL::Abstract>.
1858 See section L</"SPECIAL OPERATORS"> for details.
1862 Takes a reference to a list of "unary operators"
1863 to extend the syntax understood by L<SQL::Abstract>.
1864 See section L</"UNARY OPERATORS"> for details.
1870 =head2 insert($table, \@values || \%fieldvals, \%options)
1872 This is the simplest function. You simply give it a table name
1873 and either an arrayref of values or hashref of field/value pairs.
1874 It returns an SQL INSERT statement and a list of bind values.
1875 See the sections on L</"Inserting and Updating Arrays"> and
1876 L</"Inserting and Updating SQL"> for information on how to insert
1877 with those data types.
1879 The optional C<\%options> hash reference may contain additional
1880 options to generate the insert SQL. Currently supported options
1887 Takes either a scalar of raw SQL fields, or an array reference of
1888 field names, and adds on an SQL C<RETURNING> statement at the end.
1889 This allows you to return data generated by the insert statement
1890 (such as row IDs) without performing another C<SELECT> statement.
1891 Note, however, this is not part of the SQL standard and may not
1892 be supported by all database engines.
1896 =head2 update($table, \%fieldvals, \%where, \%options)
1898 This takes a table, hashref of field/value pairs, and an optional
1899 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1901 See the sections on L</"Inserting and Updating Arrays"> and
1902 L</"Inserting and Updating SQL"> for information on how to insert
1903 with those data types.
1905 The optional C<\%options> hash reference may contain additional
1906 options to generate the update SQL. Currently supported options
1913 See the C<returning> option to
1914 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1918 =head2 select($source, $fields, $where, $order)
1920 This returns a SQL SELECT statement and associated list of bind values, as
1921 specified by the arguments:
1927 Specification of the 'FROM' part of the statement.
1928 The argument can be either a plain scalar (interpreted as a table
1929 name, will be quoted), or an arrayref (interpreted as a list
1930 of table names, joined by commas, quoted), or a scalarref
1931 (literal SQL, not quoted).
1935 Specification of the list of fields to retrieve from
1937 The argument can be either an arrayref (interpreted as a list
1938 of field names, will be joined by commas and quoted), or a
1939 plain scalar (literal SQL, not quoted).
1940 Please observe that this API is not as flexible as that of
1941 the first argument C<$source>, for backwards compatibility reasons.
1945 Optional argument to specify the WHERE part of the query.
1946 The argument is most often a hashref, but can also be
1947 an arrayref or plain scalar --
1948 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1952 Optional argument to specify the ORDER BY part of the query.
1953 The argument can be a scalar, a hashref or an arrayref
1954 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1960 =head2 delete($table, \%where, \%options)
1962 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1963 It returns an SQL DELETE statement and list of bind values.
1965 The optional C<\%options> hash reference may contain additional
1966 options to generate the delete SQL. Currently supported options
1973 See the C<returning> option to
1974 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1978 =head2 where(\%where, $order)
1980 This is used to generate just the WHERE clause. For example,
1981 if you have an arbitrary data structure and know what the
1982 rest of your SQL is going to look like, but want an easy way
1983 to produce a WHERE clause, use this. It returns an SQL WHERE
1984 clause and list of bind values.
1987 =head2 values(\%data)
1989 This just returns the values from the hash C<%data>, in the same
1990 order that would be returned from any of the other above queries.
1991 Using this allows you to markedly speed up your queries if you
1992 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1994 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1996 Warning: This is an experimental method and subject to change.
1998 This returns arbitrarily generated SQL. It's a really basic shortcut.
1999 It will return two different things, depending on return context:
2001 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2002 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2004 These would return the following:
2006 # First calling form
2007 $stmt = "CREATE TABLE test (?, ?)";
2008 @bind = (field1, field2);
2010 # Second calling form
2011 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2013 Depending on what you're trying to do, it's up to you to choose the correct
2014 format. In this example, the second form is what you would want.
2018 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2022 ALTER SESSION SET nls_date_format = 'MM/YY'
2024 You get the idea. Strings get their case twiddled, but everything
2025 else remains verbatim.
2027 =head1 EXPORTABLE FUNCTIONS
2029 =head2 is_plain_value
2031 Determines if the supplied argument is a plain value as understood by this
2036 =item * The value is C<undef>
2038 =item * The value is a non-reference
2040 =item * The value is an object with stringification overloading
2042 =item * The value is of the form C<< { -value => $anything } >>
2046 On failure returns C<undef>, on success returns a B<scalar> reference
2047 to the original supplied argument.
2053 The stringification overloading detection is rather advanced: it takes
2054 into consideration not only the presence of a C<""> overload, but if that
2055 fails also checks for enabled
2056 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2057 on either C<0+> or C<bool>.
2059 Unfortunately testing in the field indicates that this
2060 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2061 but only when very large numbers of stringifying objects are involved.
2062 At the time of writing ( Sep 2014 ) there is no clear explanation of
2063 the direct cause, nor is there a manageably small test case that reliably
2064 reproduces the problem.
2066 If you encounter any of the following exceptions in B<random places within
2067 your application stack> - this module may be to blame:
2069 Operation "ne": no method found,
2070 left argument in overloaded package <something>,
2071 right argument in overloaded package <something>
2075 Stub found while resolving method "???" overloading """" in package <something>
2077 If you fall victim to the above - please attempt to reduce the problem
2078 to something that could be sent to the L<SQL::Abstract developers
2079 |DBIx::Class/GETTING HELP/SUPPORT>
2080 (either publicly or privately). As a workaround in the meantime you can
2081 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2082 value, which will most likely eliminate your problem (at the expense of
2083 not being able to properly detect exotic forms of stringification).
2085 This notice and environment variable will be removed in a future version,
2086 as soon as the underlying problem is found and a reliable workaround is
2091 =head2 is_literal_value
2093 Determines if the supplied argument is a literal value as understood by this
2098 =item * C<\$sql_string>
2100 =item * C<\[ $sql_string, @bind_values ]>
2104 On failure returns C<undef>, on success returns an B<array> reference
2105 containing the unpacked version of the supplied literal SQL and bind values.
2107 =head1 WHERE CLAUSES
2111 This module uses a variation on the idea from L<DBIx::Abstract>. It
2112 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2113 module is that things in arrays are OR'ed, and things in hashes
2116 The easiest way to explain is to show lots of examples. After
2117 each C<%where> hash shown, it is assumed you used:
2119 my($stmt, @bind) = $sql->where(\%where);
2121 However, note that the C<%where> hash can be used directly in any
2122 of the other functions as well, as described above.
2124 =head2 Key-value pairs
2126 So, let's get started. To begin, a simple hash:
2130 status => 'completed'
2133 Is converted to SQL C<key = val> statements:
2135 $stmt = "WHERE user = ? AND status = ?";
2136 @bind = ('nwiger', 'completed');
2138 One common thing I end up doing is having a list of values that
2139 a field can be in. To do this, simply specify a list inside of
2144 status => ['assigned', 'in-progress', 'pending'];
2147 This simple code will create the following:
2149 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2150 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2152 A field associated to an empty arrayref will be considered a
2153 logical false and will generate 0=1.
2155 =head2 Tests for NULL values
2157 If the value part is C<undef> then this is converted to SQL <IS NULL>
2166 $stmt = "WHERE user = ? AND status IS NULL";
2169 To test if a column IS NOT NULL:
2173 status => { '!=', undef },
2176 =head2 Specific comparison operators
2178 If you want to specify a different type of operator for your comparison,
2179 you can use a hashref for a given column:
2183 status => { '!=', 'completed' }
2186 Which would generate:
2188 $stmt = "WHERE user = ? AND status != ?";
2189 @bind = ('nwiger', 'completed');
2191 To test against multiple values, just enclose the values in an arrayref:
2193 status => { '=', ['assigned', 'in-progress', 'pending'] };
2195 Which would give you:
2197 "WHERE status = ? OR status = ? OR status = ?"
2200 The hashref can also contain multiple pairs, in which case it is expanded
2201 into an C<AND> of its elements:
2205 status => { '!=', 'completed', -not_like => 'pending%' }
2208 # Or more dynamically, like from a form
2209 $where{user} = 'nwiger';
2210 $where{status}{'!='} = 'completed';
2211 $where{status}{'-not_like'} = 'pending%';
2213 # Both generate this
2214 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2215 @bind = ('nwiger', 'completed', 'pending%');
2218 To get an OR instead, you can combine it with the arrayref idea:
2222 priority => [ { '=', 2 }, { '>', 5 } ]
2225 Which would generate:
2227 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2228 @bind = ('2', '5', 'nwiger');
2230 If you want to include literal SQL (with or without bind values), just use a
2231 scalar reference or reference to an arrayref as the value:
2234 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2235 date_expires => { '<' => \"now()" }
2238 Which would generate:
2240 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2241 @bind = ('11/26/2008');
2244 =head2 Logic and nesting operators
2246 In the example above,
2247 there is a subtle trap if you want to say something like
2248 this (notice the C<AND>):
2250 WHERE priority != ? AND priority != ?
2252 Because, in Perl you I<can't> do this:
2254 priority => { '!=' => 2, '!=' => 1 }
2256 As the second C<!=> key will obliterate the first. The solution
2257 is to use the special C<-modifier> form inside an arrayref:
2259 priority => [ -and => {'!=', 2},
2263 Normally, these would be joined by C<OR>, but the modifier tells it
2264 to use C<AND> instead. (Hint: You can use this in conjunction with the
2265 C<logic> option to C<new()> in order to change the way your queries
2266 work by default.) B<Important:> Note that the C<-modifier> goes
2267 B<INSIDE> the arrayref, as an extra first element. This will
2268 B<NOT> do what you think it might:
2270 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2272 Here is a quick list of equivalencies, since there is some overlap:
2275 status => {'!=', 'completed', 'not like', 'pending%' }
2276 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2279 status => {'=', ['assigned', 'in-progress']}
2280 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2281 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2285 =head2 Special operators: IN, BETWEEN, etc.
2287 You can also use the hashref format to compare a list of fields using the
2288 C<IN> comparison operator, by specifying the list as an arrayref:
2291 status => 'completed',
2292 reportid => { -in => [567, 2335, 2] }
2295 Which would generate:
2297 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2298 @bind = ('completed', '567', '2335', '2');
2300 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2303 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2304 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2305 'sqltrue' (by default: C<1=1>).
2307 In addition to the array you can supply a chunk of literal sql or
2308 literal sql with bind:
2311 customer => { -in => \[
2312 'SELECT cust_id FROM cust WHERE balance > ?',
2315 status => { -in => \'SELECT status_codes FROM states' },
2321 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2322 AND status IN ( SELECT status_codes FROM states )
2326 Finally, if the argument to C<-in> is not a reference, it will be
2327 treated as a single-element array.
2329 Another pair of operators is C<-between> and C<-not_between>,
2330 used with an arrayref of two values:
2334 completion_date => {
2335 -not_between => ['2002-10-01', '2003-02-06']
2341 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2343 Just like with C<-in> all plausible combinations of literal SQL
2347 start0 => { -between => [ 1, 2 ] },
2348 start1 => { -between => \["? AND ?", 1, 2] },
2349 start2 => { -between => \"lower(x) AND upper(y)" },
2350 start3 => { -between => [
2352 \["upper(?)", 'stuff' ],
2359 ( start0 BETWEEN ? AND ? )
2360 AND ( start1 BETWEEN ? AND ? )
2361 AND ( start2 BETWEEN lower(x) AND upper(y) )
2362 AND ( start3 BETWEEN lower(x) AND upper(?) )
2364 @bind = (1, 2, 1, 2, 'stuff');
2367 These are the two builtin "special operators"; but the
2368 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2370 =head2 Unary operators: bool
2372 If you wish to test against boolean columns or functions within your
2373 database you can use the C<-bool> and C<-not_bool> operators. For
2374 example to test the column C<is_user> being true and the column
2375 C<is_enabled> being false you would use:-
2379 -not_bool => 'is_enabled',
2384 WHERE is_user AND NOT is_enabled
2386 If a more complex combination is required, testing more conditions,
2387 then you should use the and/or operators:-
2392 -not_bool => { two=> { -rlike => 'bar' } },
2393 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2404 (NOT ( three = ? OR three > ? ))
2407 =head2 Nested conditions, -and/-or prefixes
2409 So far, we've seen how multiple conditions are joined with a top-level
2410 C<AND>. We can change this by putting the different conditions we want in
2411 hashes and then putting those hashes in an array. For example:
2416 status => { -like => ['pending%', 'dispatched'] },
2420 status => 'unassigned',
2424 This data structure would create the following:
2426 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2427 OR ( user = ? AND status = ? ) )";
2428 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2431 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2432 to change the logic inside:
2438 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2439 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2446 $stmt = "WHERE ( user = ?
2447 AND ( ( workhrs > ? AND geo = ? )
2448 OR ( workhrs < ? OR geo = ? ) ) )";
2449 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2451 =head3 Algebraic inconsistency, for historical reasons
2453 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2454 operator goes C<outside> of the nested structure; whereas when connecting
2455 several constraints on one column, the C<-and> operator goes
2456 C<inside> the arrayref. Here is an example combining both features:
2459 -and => [a => 1, b => 2],
2460 -or => [c => 3, d => 4],
2461 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2466 WHERE ( ( ( a = ? AND b = ? )
2467 OR ( c = ? OR d = ? )
2468 OR ( e LIKE ? AND e LIKE ? ) ) )
2470 This difference in syntax is unfortunate but must be preserved for
2471 historical reasons. So be careful: the two examples below would
2472 seem algebraically equivalent, but they are not
2475 { -like => 'foo%' },
2476 { -like => '%bar' },
2478 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2481 { col => { -like => 'foo%' } },
2482 { col => { -like => '%bar' } },
2484 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2487 =head2 Literal SQL and value type operators
2489 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2490 side" is a column name and the "right side" is a value (normally rendered as
2491 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2492 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2493 alter this behavior. There are several ways of doing so.
2497 This is a virtual operator that signals the string to its right side is an
2498 identifier (a column name) and not a value. For example to compare two
2499 columns you would write:
2502 priority => { '<', 2 },
2503 requestor => { -ident => 'submitter' },
2508 $stmt = "WHERE priority < ? AND requestor = submitter";
2511 If you are maintaining legacy code you may see a different construct as
2512 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2517 This is a virtual operator that signals that the construct to its right side
2518 is a value to be passed to DBI. This is for example necessary when you want
2519 to write a where clause against an array (for RDBMS that support such
2520 datatypes). For example:
2523 array => { -value => [1, 2, 3] }
2528 $stmt = 'WHERE array = ?';
2529 @bind = ([1, 2, 3]);
2531 Note that if you were to simply say:
2537 the result would probably not be what you wanted:
2539 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2544 Finally, sometimes only literal SQL will do. To include a random snippet
2545 of SQL verbatim, you specify it as a scalar reference. Consider this only
2546 as a last resort. Usually there is a better way. For example:
2549 priority => { '<', 2 },
2550 requestor => { -in => \'(SELECT name FROM hitmen)' },
2555 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2558 Note that in this example, you only get one bind parameter back, since
2559 the verbatim SQL is passed as part of the statement.
2563 Never use untrusted input as a literal SQL argument - this is a massive
2564 security risk (there is no way to check literal snippets for SQL
2565 injections and other nastyness). If you need to deal with untrusted input
2566 use literal SQL with placeholders as described next.
2568 =head3 Literal SQL with placeholders and bind values (subqueries)
2570 If the literal SQL to be inserted has placeholders and bind values,
2571 use a reference to an arrayref (yes this is a double reference --
2572 not so common, but perfectly legal Perl). For example, to find a date
2573 in Postgres you can use something like this:
2576 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2581 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2584 Note that you must pass the bind values in the same format as they are returned
2585 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2586 to C<columns>, you must provide the bind values in the
2587 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2588 scalar value; most commonly the column name, but you can use any scalar value
2589 (including references and blessed references), L<SQL::Abstract> will simply
2590 pass it through intact. So if C<bindtype> is set to C<columns> the above
2591 example will look like:
2594 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2597 Literal SQL is especially useful for nesting parenthesized clauses in the
2598 main SQL query. Here is a first example:
2600 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2604 bar => \["IN ($sub_stmt)" => @sub_bind],
2609 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2610 WHERE c2 < ? AND c3 LIKE ?))";
2611 @bind = (1234, 100, "foo%");
2613 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2614 are expressed in the same way. Of course the C<$sub_stmt> and
2615 its associated bind values can be generated through a former call
2618 my ($sub_stmt, @sub_bind)
2619 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2620 c3 => {-like => "foo%"}});
2623 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2626 In the examples above, the subquery was used as an operator on a column;
2627 but the same principle also applies for a clause within the main C<%where>
2628 hash, like an EXISTS subquery:
2630 my ($sub_stmt, @sub_bind)
2631 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2632 my %where = ( -and => [
2634 \["EXISTS ($sub_stmt)" => @sub_bind],
2639 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2640 WHERE c1 = ? AND c2 > t0.c0))";
2644 Observe that the condition on C<c2> in the subquery refers to
2645 column C<t0.c0> of the main query: this is I<not> a bind
2646 value, so we have to express it through a scalar ref.
2647 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2648 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2649 what we wanted here.
2651 Finally, here is an example where a subquery is used
2652 for expressing unary negation:
2654 my ($sub_stmt, @sub_bind)
2655 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2656 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2658 lname => {like => '%son%'},
2659 \["NOT ($sub_stmt)" => @sub_bind],
2664 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2665 @bind = ('%son%', 10, 20)
2667 =head3 Deprecated usage of Literal SQL
2669 Below are some examples of archaic use of literal SQL. It is shown only as
2670 reference for those who deal with legacy code. Each example has a much
2671 better, cleaner and safer alternative that users should opt for in new code.
2677 my %where = ( requestor => \'IS NOT NULL' )
2679 $stmt = "WHERE requestor IS NOT NULL"
2681 This used to be the way of generating NULL comparisons, before the handling
2682 of C<undef> got formalized. For new code please use the superior syntax as
2683 described in L</Tests for NULL values>.
2687 my %where = ( requestor => \'= submitter' )
2689 $stmt = "WHERE requestor = submitter"
2691 This used to be the only way to compare columns. Use the superior L</-ident>
2692 method for all new code. For example an identifier declared in such a way
2693 will be properly quoted if L</quote_char> is properly set, while the legacy
2694 form will remain as supplied.
2698 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2700 $stmt = "WHERE completed > ? AND is_ready"
2701 @bind = ('2012-12-21')
2703 Using an empty string literal used to be the only way to express a boolean.
2704 For all new code please use the much more readable
2705 L<-bool|/Unary operators: bool> operator.
2711 These pages could go on for a while, since the nesting of the data
2712 structures this module can handle are pretty much unlimited (the
2713 module implements the C<WHERE> expansion as a recursive function
2714 internally). Your best bet is to "play around" with the module a
2715 little to see how the data structures behave, and choose the best
2716 format for your data based on that.
2718 And of course, all the values above will probably be replaced with
2719 variables gotten from forms or the command line. After all, if you
2720 knew everything ahead of time, you wouldn't have to worry about
2721 dynamically-generating SQL and could just hardwire it into your
2724 =head1 ORDER BY CLAUSES
2726 Some functions take an order by clause. This can either be a scalar (just a
2727 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2728 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2731 Given | Will Generate
2732 ---------------------------------------------------------------
2734 'colA' | ORDER BY colA
2736 [qw/colA colB/] | ORDER BY colA, colB
2738 {-asc => 'colA'} | ORDER BY colA ASC
2740 {-desc => 'colB'} | ORDER BY colB DESC
2742 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2744 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2746 \'colA DESC' | ORDER BY colA DESC
2748 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2749 | /* ...with $x bound to ? */
2752 { -asc => 'colA' }, | colA ASC,
2753 { -desc => [qw/colB/] }, | colB DESC,
2754 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2755 \'colE DESC', | colE DESC,
2756 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2757 ] | /* ...with $x bound to ? */
2758 ===============================================================
2762 =head1 SPECIAL OPERATORS
2764 my $sqlmaker = SQL::Abstract->new(special_ops => [
2768 my ($self, $field, $op, $arg) = @_;
2774 handler => 'method_name',
2778 A "special operator" is a SQL syntactic clause that can be
2779 applied to a field, instead of a usual binary operator.
2782 WHERE field IN (?, ?, ?)
2783 WHERE field BETWEEN ? AND ?
2784 WHERE MATCH(field) AGAINST (?, ?)
2786 Special operators IN and BETWEEN are fairly standard and therefore
2787 are builtin within C<SQL::Abstract> (as the overridable methods
2788 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2789 like the MATCH .. AGAINST example above which is specific to MySQL,
2790 you can write your own operator handlers - supply a C<special_ops>
2791 argument to the C<new> method. That argument takes an arrayref of
2792 operator definitions; each operator definition is a hashref with two
2799 the regular expression to match the operator
2803 Either a coderef or a plain scalar method name. In both cases
2804 the expected return is C<< ($sql, @bind) >>.
2806 When supplied with a method name, it is simply called on the
2807 L<SQL::Abstract> object as:
2809 $self->$method_name($field, $op, $arg)
2813 $field is the LHS of the operator
2814 $op is the part that matched the handler regex
2817 When supplied with a coderef, it is called as:
2819 $coderef->($self, $field, $op, $arg)
2824 For example, here is an implementation
2825 of the MATCH .. AGAINST syntax for MySQL
2827 my $sqlmaker = SQL::Abstract->new(special_ops => [
2829 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2830 {regex => qr/^match$/i,
2832 my ($self, $field, $op, $arg) = @_;
2833 $arg = [$arg] if not ref $arg;
2834 my $label = $self->_quote($field);
2835 my ($placeholder) = $self->_convert('?');
2836 my $placeholders = join ", ", (($placeholder) x @$arg);
2837 my $sql = $self->_sqlcase('match') . " ($label) "
2838 . $self->_sqlcase('against') . " ($placeholders) ";
2839 my @bind = $self->_bindtype($field, @$arg);
2840 return ($sql, @bind);
2847 =head1 UNARY OPERATORS
2849 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2853 my ($self, $op, $arg) = @_;
2859 handler => 'method_name',
2863 A "unary operator" is a SQL syntactic clause that can be
2864 applied to a field - the operator goes before the field
2866 You can write your own operator handlers - supply a C<unary_ops>
2867 argument to the C<new> method. That argument takes an arrayref of
2868 operator definitions; each operator definition is a hashref with two
2875 the regular expression to match the operator
2879 Either a coderef or a plain scalar method name. In both cases
2880 the expected return is C<< $sql >>.
2882 When supplied with a method name, it is simply called on the
2883 L<SQL::Abstract> object as:
2885 $self->$method_name($op, $arg)
2889 $op is the part that matched the handler regex
2890 $arg is the RHS or argument of the operator
2892 When supplied with a coderef, it is called as:
2894 $coderef->($self, $op, $arg)
2902 Thanks to some benchmarking by Mark Stosberg, it turns out that
2903 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2904 I must admit this wasn't an intentional design issue, but it's a
2905 byproduct of the fact that you get to control your C<DBI> handles
2908 To maximize performance, use a code snippet like the following:
2910 # prepare a statement handle using the first row
2911 # and then reuse it for the rest of the rows
2913 for my $href (@array_of_hashrefs) {
2914 $stmt ||= $sql->insert('table', $href);
2915 $sth ||= $dbh->prepare($stmt);
2916 $sth->execute($sql->values($href));
2919 The reason this works is because the keys in your C<$href> are sorted
2920 internally by B<SQL::Abstract>. Thus, as long as your data retains
2921 the same structure, you only have to generate the SQL the first time
2922 around. On subsequent queries, simply use the C<values> function provided
2923 by this module to return your values in the correct order.
2925 However this depends on the values having the same type - if, for
2926 example, the values of a where clause may either have values
2927 (resulting in sql of the form C<column = ?> with a single bind
2928 value), or alternatively the values might be C<undef> (resulting in
2929 sql of the form C<column IS NULL> with no bind value) then the
2930 caching technique suggested will not work.
2934 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2935 really like this part (I do, at least). Building up a complex query
2936 can be as simple as the following:
2943 use CGI::FormBuilder;
2946 my $form = CGI::FormBuilder->new(...);
2947 my $sql = SQL::Abstract->new;
2949 if ($form->submitted) {
2950 my $field = $form->field;
2951 my $id = delete $field->{id};
2952 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2955 Of course, you would still have to connect using C<DBI> to run the
2956 query, but the point is that if you make your form look like your
2957 table, the actual query script can be extremely simplistic.
2959 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2960 a fast interface to returning and formatting data. I frequently
2961 use these three modules together to write complex database query
2962 apps in under 50 lines.
2964 =head1 HOW TO CONTRIBUTE
2966 Contributions are always welcome, in all usable forms (we especially
2967 welcome documentation improvements). The delivery methods include git-
2968 or unified-diff formatted patches, GitHub pull requests, or plain bug
2969 reports either via RT or the Mailing list. Contributors are generally
2970 granted full access to the official repository after their first several
2971 patches pass successful review.
2973 This project is maintained in a git repository. The code and related tools are
2974 accessible at the following locations:
2978 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2980 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2982 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2984 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2990 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2991 Great care has been taken to preserve the I<published> behavior
2992 documented in previous versions in the 1.* family; however,
2993 some features that were previously undocumented, or behaved
2994 differently from the documentation, had to be changed in order
2995 to clarify the semantics. Hence, client code that was relying
2996 on some dark areas of C<SQL::Abstract> v1.*
2997 B<might behave differently> in v1.50.
2999 The main changes are:
3005 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3009 support for the { operator => \"..." } construct (to embed literal SQL)
3013 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3017 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3021 defensive programming: check arguments
3025 fixed bug with global logic, which was previously implemented
3026 through global variables yielding side-effects. Prior versions would
3027 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3028 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3029 Now this is interpreted
3030 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3035 fixed semantics of _bindtype on array args
3039 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3040 we just avoid shifting arrays within that tree.
3044 dropped the C<_modlogic> function
3048 =head1 ACKNOWLEDGEMENTS
3050 There are a number of individuals that have really helped out with
3051 this module. Unfortunately, most of them submitted bugs via CPAN
3052 so I have no idea who they are! But the people I do know are:
3054 Ash Berlin (order_by hash term support)
3055 Matt Trout (DBIx::Class support)
3056 Mark Stosberg (benchmarking)
3057 Chas Owens (initial "IN" operator support)
3058 Philip Collins (per-field SQL functions)
3059 Eric Kolve (hashref "AND" support)
3060 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3061 Dan Kubb (support for "quote_char" and "name_sep")
3062 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3063 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3064 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3065 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3066 Oliver Charles (support for "RETURNING" after "INSERT")
3072 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3076 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3078 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3080 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3081 While not an official support venue, C<DBIx::Class> makes heavy use of
3082 C<SQL::Abstract>, and as such list members there are very familiar with
3083 how to create queries.
3087 This module is free software; you may copy this under the same
3088 terms as perl itself (either the GNU General Public License or
3089 the Artistic License)