1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
164 $opt{unary_ops} ||= [];
166 # rudimentary sanity-check for user supplied bits treated as functions/operators
167 # If a purported function matches this regular expression, an exception is thrown.
168 # Literal SQL is *NOT* subject to this check, only functions (and column names
169 # when quoting is not in effect)
172 # need to guard against ()'s in column names too, but this will break tons of
173 # hacks... ideas anyone?
174 $opt{injection_guard} ||= qr/
180 $opt{node_types} = +{
181 map +("-$_" => '_render_'.$_),
182 qw(op func value bind ident literal)
185 $opt{expand_unary} = {};
187 return bless \%opt, $class;
190 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
191 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
193 sub _assert_pass_injection_guard {
194 if ($_[1] =~ $_[0]->{injection_guard}) {
195 my $class = ref $_[0];
196 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
197 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
198 . "{injection_guard} attribute to ${class}->new()"
203 #======================================================================
205 #======================================================================
209 my $table = $self->_table(shift);
210 my $data = shift || return;
213 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
214 my ($sql, @bind) = $self->$method($data);
215 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
217 if ($options->{returning}) {
218 my ($s, @b) = $self->_insert_returning($options);
223 return wantarray ? ($sql, @bind) : $sql;
226 # So that subclasses can override INSERT ... RETURNING separately from
227 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
228 sub _insert_returning { shift->_returning(@_) }
231 my ($self, $options) = @_;
233 my $f = $options->{returning};
235 my ($sql, @bind) = $self->_render_expr(
236 $self->_expand_maybe_list_expr($f, undef, -ident)
239 ? $self->_sqlcase(' returning ') . $sql
240 : ($self->_sqlcase(' returning ').$sql, @bind);
243 sub _insert_HASHREF { # explicit list of fields and then values
244 my ($self, $data) = @_;
246 my @fields = sort keys %$data;
248 my ($sql, @bind) = $self->_insert_values($data);
251 $_ = $self->_quote($_) foreach @fields;
252 $sql = "( ".join(", ", @fields).") ".$sql;
254 return ($sql, @bind);
257 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
258 my ($self, $data) = @_;
260 # no names (arrayref) so can't generate bindtype
261 $self->{bindtype} ne 'columns'
262 or belch "can't do 'columns' bindtype when called with arrayref";
264 my (@values, @all_bind);
265 foreach my $value (@$data) {
266 my ($values, @bind) = $self->_insert_value(undef, $value);
267 push @values, $values;
268 push @all_bind, @bind;
270 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
271 return ($sql, @all_bind);
274 sub _insert_ARRAYREFREF { # literal SQL with bind
275 my ($self, $data) = @_;
277 my ($sql, @bind) = @${$data};
278 $self->_assert_bindval_matches_bindtype(@bind);
280 return ($sql, @bind);
284 sub _insert_SCALARREF { # literal SQL without bind
285 my ($self, $data) = @_;
291 my ($self, $data) = @_;
293 my (@values, @all_bind);
294 foreach my $column (sort keys %$data) {
295 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
296 push @values, $values;
297 push @all_bind, @bind;
299 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
300 return ($sql, @all_bind);
304 my ($self, $column, $v) = @_;
306 return $self->_render_expr(
307 $self->_expand_insert_value($column, $v)
311 sub _expand_insert_value {
312 my ($self, $column, $v) = @_;
314 if (ref($v) eq 'ARRAY') {
315 if ($self->{array_datatypes}) {
316 return +{ -bind => [ $column, $v ] };
318 my ($sql, @bind) = @$v;
319 $self->_assert_bindval_matches_bindtype(@bind);
320 return +{ -literal => $v };
322 if (ref($v) eq 'HASH') {
323 if (grep !/^-/, keys %$v) {
324 belch "HASH ref as bind value in insert is not supported";
325 return +{ -bind => [ $column, $v ] };
329 return +{ -bind => [ $column, undef ] };
331 local our $Cur_Col_Meta = $column;
332 return $self->_expand_expr($v);
337 #======================================================================
339 #======================================================================
344 my $table = $self->_table(shift);
345 my $data = shift || return;
349 # first build the 'SET' part of the sql statement
350 puke "Unsupported data type specified to \$sql->update"
351 unless ref $data eq 'HASH';
353 my ($sql, @all_bind) = $self->_update_set_values($data);
354 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
358 my($where_sql, @where_bind) = $self->where($where);
360 push @all_bind, @where_bind;
363 if ($options->{returning}) {
364 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
365 $sql .= $returning_sql;
366 push @all_bind, @returning_bind;
369 return wantarray ? ($sql, @all_bind) : $sql;
372 sub _update_set_values {
373 my ($self, $data) = @_;
375 return $self->_render_expr(
376 $self->_expand_update_set_values($data),
380 sub _expand_update_set_values {
381 my ($self, $data) = @_;
382 $self->_expand_maybe_list_expr( [
385 $set = { -bind => $_ } unless defined $set;
386 +{ -op => [ '=', { -ident => $k }, $set ] };
392 ? ($self->{array_datatypes}
393 ? [ $k, +{ -bind => [ $k, $v ] } ]
394 : [ $k, +{ -literal => $v } ])
396 local our $Cur_Col_Meta = $k;
397 [ $k, $self->_expand_expr($v) ]
404 # So that subclasses can override UPDATE ... RETURNING separately from
406 sub _update_returning { shift->_returning(@_) }
410 #======================================================================
412 #======================================================================
417 my $table = $self->_table(shift);
418 my $fields = shift || '*';
422 my ($fields_sql, @bind) = $self->_select_fields($fields);
424 my ($where_sql, @where_bind) = $self->where($where, $order);
425 push @bind, @where_bind;
427 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
428 $self->_sqlcase('from'), $table)
431 return wantarray ? ($sql, @bind) : $sql;
435 my ($self, $fields) = @_;
436 return $fields unless ref($fields);
437 return $self->_render_expr(
438 $self->_expand_maybe_list_expr($fields, undef, '-ident')
442 #======================================================================
444 #======================================================================
449 my $table = $self->_table(shift);
453 my($where_sql, @bind) = $self->where($where);
454 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
456 if ($options->{returning}) {
457 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
458 $sql .= $returning_sql;
459 push @bind, @returning_bind;
462 return wantarray ? ($sql, @bind) : $sql;
465 # So that subclasses can override DELETE ... RETURNING separately from
467 sub _delete_returning { shift->_returning(@_) }
471 #======================================================================
473 #======================================================================
477 # Finally, a separate routine just to handle WHERE clauses
479 my ($self, $where, $order) = @_;
481 local $self->{convert_where} = $self->{convert};
484 my ($sql, @bind) = defined($where)
485 ? $self->_recurse_where($where)
487 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
491 my ($order_sql, @order_bind) = $self->_order_by($order);
493 push @bind, @order_bind;
496 return wantarray ? ($sql, @bind) : $sql;
500 my ($self, $expr, $logic, $default_scalar_to) = @_;
501 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
502 return undef unless defined($expr);
503 if (ref($expr) eq 'HASH') {
504 if (keys %$expr > 1) {
508 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
512 return unless %$expr;
513 return $self->_expand_expr_hashpair(%$expr, $logic);
515 if (ref($expr) eq 'ARRAY') {
516 my $logic = lc($logic || $self->{logic});
517 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
523 while (my ($el) = splice @expr, 0, 1) {
524 puke "Supplying an empty left hand side argument is not supported in array-pairs"
525 unless defined($el) and length($el);
526 my $elref = ref($el);
528 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
529 } elsif ($elref eq 'ARRAY') {
530 push(@res, $self->_expand_expr($el)) if @$el;
531 } elsif (my $l = is_literal_value($el)) {
532 push @res, { -literal => $l };
533 } elsif ($elref eq 'HASH') {
534 push @res, $self->_expand_expr($el);
539 return { -op => [ $logic, @res ] };
541 if (my $literal = is_literal_value($expr)) {
542 return +{ -literal => $literal };
544 if (!ref($expr) or Scalar::Util::blessed($expr)) {
545 if (my $d = $Default_Scalar_To) {
546 return +{ $d => $expr };
548 if (my $m = our $Cur_Col_Meta) {
549 return +{ -bind => [ $m, $expr ] };
551 return +{ -value => $expr };
556 sub _expand_expr_hashpair {
557 my ($self, $k, $v, $logic) = @_;
558 unless (defined($k) and length($k)) {
559 if (defined($k) and my $literal = is_literal_value($v)) {
560 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
561 return { -literal => $literal };
563 puke "Supplying an empty left hand side argument is not supported";
566 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
567 if ($k =~ s/ [_\s]? \d+ $//x ) {
568 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
569 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
572 return $self->_expand_expr($v);
576 return $self->_expand_expr($v);
578 puke "-bool => undef not supported" unless defined($v);
579 return { -ident => $v };
582 return { -op => [ 'not', $self->_expand_expr($v) ] };
584 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
587 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
590 if (my ($logic) = $k =~ /^-(and|or)$/i) {
591 if (ref($v) eq 'HASH') {
592 return $self->_expand_expr($v, $logic);
594 if (ref($v) eq 'ARRAY') {
595 return $self->_expand_expr($v, $logic);
600 $op =~ s/^-// if length($op) > 1;
602 # top level special ops are illegal in general
603 puke "Illegal use of top-level '-$op'"
604 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
605 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
606 return { -op => [ $op, $v ] };
609 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
610 return +{ -bind => [ $m, $v ] };
612 if (my $custom = $self->{expand_unary}{$k}) {
613 return $self->$custom($v);
615 if ($self->{node_types}{$k}) {
621 and (keys %$v)[0] =~ /^-/
623 my ($func) = $k =~ /^-(.*)$/;
624 return +{ -func => [ $func, $self->_expand_expr($v) ] };
626 if (!ref($v) or is_literal_value($v)) {
627 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
634 and exists $v->{-value}
635 and not defined $v->{-value}
638 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
640 if (!ref($v) or Scalar::Util::blessed($v)) {
641 my $d = our $Default_Scalar_To;
646 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
650 if (ref($v) eq 'HASH') {
654 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
661 $self->_assert_pass_injection_guard($vk);
662 if ($vk =~ s/ [_\s]? \d+ $//x ) {
663 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
664 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
666 if ($vk =~ /^(?:not[ _])?between$/) {
667 local our $Cur_Col_Meta = $k;
668 my @rhs = map $self->_expand_expr($_),
669 ref($vv) eq 'ARRAY' ? @$vv : $vv;
671 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
673 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
675 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
678 join(' ', split '_', $vk),
683 if ($vk =~ /^(?:not[ _])?in$/) {
684 if (my $literal = is_literal_value($vv)) {
685 my ($sql, @bind) = @$literal;
686 my $opened_sql = $self->_open_outer_paren($sql);
688 $vk, { -ident => $k },
689 [ { -literal => [ $opened_sql, @bind ] } ]
693 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
694 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
695 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
696 . 'will emit the logically correct SQL instead of raising this exception)'
698 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
700 my @rhs = map $self->_expand_expr($_),
701 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
702 map { defined($_) ? $_: puke($undef_err) }
703 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
704 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
707 join(' ', split '_', $vk),
712 if ($vk eq 'ident') {
713 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
714 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
722 if ($vk eq 'value') {
723 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
727 { -bind => [ $k, $vv ] }
730 if ($vk =~ /^is(?:[ _]not)?$/) {
731 puke "$vk can only take undef as argument"
735 and exists($vv->{-value})
736 and !defined($vv->{-value})
739 return +{ -op => [ $vk.' null', { -ident => $k } ] };
741 if ($vk =~ /^(and|or)$/) {
742 if (ref($vv) eq 'HASH') {
745 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
750 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
751 return { -op => [ $vk, { -ident => $k }, $vv ] };
753 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
757 { -op => [ $vk, $vv ] }
760 if (ref($vv) eq 'ARRAY') {
761 my ($logic, @values) = (
762 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
767 $vk =~ $self->{inequality_op}
768 or join(' ', split '_', $vk) =~ $self->{not_like_op}
770 if (lc($logic) eq '-or' and @values > 1) {
771 my $op = uc join ' ', split '_', $vk;
772 belch "A multi-element arrayref as an argument to the inequality op '$op' "
773 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
774 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
779 # try to DWIM on equality operators
780 my $op = join ' ', split '_', $vk;
782 $op =~ $self->{equality_op} ? $self->sqlfalse
783 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
784 : $op =~ $self->{inequality_op} ? $self->sqltrue
785 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
786 : puke "operator '$op' applied on an empty array (field '$k')";
790 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
798 and exists $vv->{-value}
799 and not defined $vv->{-value}
802 my $op = join ' ', split '_', $vk;
804 $op =~ /^not$/i ? 'is not' # legacy
805 : $op =~ $self->{equality_op} ? 'is'
806 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
807 : $op =~ $self->{inequality_op} ? 'is not'
808 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
809 : puke "unexpected operator '$op' with undef operand";
810 return +{ -op => [ $is.' null', { -ident => $k } ] };
812 local our $Cur_Col_Meta = $k;
816 $self->_expand_expr($vv)
819 if (ref($v) eq 'ARRAY') {
820 return $self->sqlfalse unless @$v;
821 $self->_debug("ARRAY($k) means distribute over elements");
823 $v->[0] =~ /^-((?:and|or))$/i
824 ? ($v = [ @{$v}[1..$#$v] ], $1)
825 : ($self->{logic} || 'or')
829 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
832 if (my $literal = is_literal_value($v)) {
834 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
837 my ($sql, @bind) = @$literal;
838 if ($self->{bindtype} eq 'columns') {
840 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
841 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
845 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
851 my ($self, $expr) = @_;
852 my ($k, $v, @rest) = %$expr;
854 if (my $meth = $self->{node_types}{$k}) {
855 return $self->$meth($v);
857 die "notreached: $k";
861 my ($self, $where, $logic) = @_;
863 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
865 my $where_exp = $self->_expand_expr($where, $logic);
867 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
869 # dispatch on appropriate method according to refkind of $where
870 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
872 # my ($sql, @bind) = $self->$method($where_exp, $logic);
874 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
876 # DBIx::Class used to call _recurse_where in scalar context
877 # something else might too...
879 return ($sql, @bind);
882 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
888 my ($self, $ident) = @_;
890 return $self->_convert($self->_quote($ident));
894 my ($self, $value) = @_;
896 return ($self->_convert('?'), $self->_bindtype(undef, $value));
899 my %unop_postfix = map +($_ => 1),
900 'is null', 'is not null',
908 my ($self, $args) = @_;
909 my ($left, $low, $high) = @$args;
910 my ($rhsql, @rhbind) = do {
912 puke "Single arg to between must be a literal"
913 unless $low->{-literal};
916 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
917 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
918 @{$l}[1..$#$l], @{$h}[1..$#$h])
921 my ($lhsql, @lhbind) = $self->_render_expr($left);
923 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
927 }), 'between', 'not between'),
931 my ($self, $args) = @_;
932 my ($lhs, $rhs) = @$args;
935 my ($sql, @bind) = $self->_render_expr($_);
936 push @in_bind, @bind;
939 my ($lhsql, @lbind) = $self->_render_expr($lhs);
941 $lhsql.' '.$self->_sqlcase($op).' ( '
952 my ($op, @args) = @$v;
953 $op =~ s/^-// if length($op) > 1;
955 if (my $h = $special{$op}) {
956 return $self->$h(\@args);
958 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
959 puke "Special op '${op}' requires first value to be identifier"
960 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
961 return $self->${\($us->{handler})}($k, $op, $args[1]);
963 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
964 return $self->${\($us->{handler})}($op, $args[0]);
966 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
967 if (@args == 1 and $op !~ /^(and|or)$/) {
968 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
969 my $op_sql = $self->_sqlcase($final_op);
971 $unop_postfix{lc($final_op)}
972 ? "${expr_sql} ${op_sql}"
973 : "${op_sql} ${expr_sql}"
975 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
977 my @parts = map [ $self->_render_expr($_) ], @args;
978 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
979 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
984 map @{$_}[1..$#$_], @parts
991 my ($self, $rest) = @_;
992 my ($func, @args) = @$rest;
996 push @arg_sql, shift @x;
998 } map [ $self->_render_expr($_) ], @args;
999 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1003 my ($self, $bind) = @_;
1004 return ($self->_convert('?'), $self->_bindtype(@$bind));
1007 sub _render_literal {
1008 my ($self, $literal) = @_;
1009 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1013 # Some databases (SQLite) treat col IN (1, 2) different from
1014 # col IN ( (1, 2) ). Use this to strip all outer parens while
1015 # adding them back in the corresponding method
1016 sub _open_outer_paren {
1017 my ($self, $sql) = @_;
1019 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1021 # there are closing parens inside, need the heavy duty machinery
1022 # to reevaluate the extraction starting from $sql (full reevaluation)
1023 if ($inner =~ /\)/) {
1024 require Text::Balanced;
1026 my (undef, $remainder) = do {
1027 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1029 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1032 # the entire expression needs to be a balanced bracketed thing
1033 # (after an extract no remainder sans trailing space)
1034 last if defined $remainder and $remainder =~ /\S/;
1044 #======================================================================
1046 #======================================================================
1049 my ($self, $arg) = @_;
1051 return '' unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1053 my $expander = sub {
1054 my ($self, $dir, $expr) = @_;
1055 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1056 foreach my $arg (@to_expand) {
1060 and grep /^-(asc|desc)$/, keys %$arg
1062 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1065 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1066 map $self->_expand_expr($_, undef, -ident), @to_expand;
1067 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1070 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1071 sub { shift->$expander(asc => @_) },
1072 sub { shift->$expander(desc => @_) },
1075 my $expanded = $self->$expander(undef, $arg);
1077 my ($sql, @bind) = $self->_render_expr($expanded);
1079 my $final_sql = $self->_sqlcase(' order by ').$sql;
1081 return wantarray ? ($final_sql, @bind) : $final_sql;
1084 #======================================================================
1085 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1086 #======================================================================
1091 ($self->_render_expr(
1092 $self->_expand_maybe_list_expr($from, undef, -ident)
1097 #======================================================================
1099 #======================================================================
1101 sub _expand_maybe_list_expr {
1102 my ($self, $expr, $logic, $default) = @_;
1104 if (ref($expr) eq 'ARRAY') {
1106 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1113 return $self->_expand_expr($e, $logic, $default);
1116 # highly optimized, as it's called way too often
1118 # my ($self, $label) = @_;
1120 return '' unless defined $_[1];
1121 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1122 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1124 unless ($_[0]->{quote_char}) {
1125 if (ref($_[1]) eq 'ARRAY') {
1126 return join($_[0]->{name_sep}||'.', @{$_[1]});
1128 $_[0]->_assert_pass_injection_guard($_[1]);
1133 my $qref = ref $_[0]->{quote_char};
1135 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1136 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1137 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1139 my $esc = $_[0]->{escape_char} || $r;
1141 # parts containing * are naturally unquoted
1143 $_[0]->{name_sep}||'',
1147 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1149 (ref($_[1]) eq 'ARRAY'
1153 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1161 # Conversion, if applicable
1163 #my ($self, $arg) = @_;
1164 if ($_[0]->{convert_where}) {
1165 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1172 #my ($self, $col, @vals) = @_;
1173 # called often - tighten code
1174 return $_[0]->{bindtype} eq 'columns'
1175 ? map {[$_[1], $_]} @_[2 .. $#_]
1180 # Dies if any element of @bind is not in [colname => value] format
1181 # if bindtype is 'columns'.
1182 sub _assert_bindval_matches_bindtype {
1183 # my ($self, @bind) = @_;
1185 if ($self->{bindtype} eq 'columns') {
1187 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1188 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1194 sub _join_sql_clauses {
1195 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1197 if (@$clauses_aref > 1) {
1198 my $join = " " . $self->_sqlcase($logic) . " ";
1199 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1200 return ($sql, @$bind_aref);
1202 elsif (@$clauses_aref) {
1203 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1206 return (); # if no SQL, ignore @$bind_aref
1211 # Fix SQL case, if so requested
1213 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1214 # don't touch the argument ... crooked logic, but let's not change it!
1215 return $_[0]->{case} ? $_[1] : uc($_[1]);
1219 #======================================================================
1220 # DISPATCHING FROM REFKIND
1221 #======================================================================
1224 my ($self, $data) = @_;
1226 return 'UNDEF' unless defined $data;
1228 # blessed objects are treated like scalars
1229 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1231 return 'SCALAR' unless $ref;
1234 while ($ref eq 'REF') {
1236 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1240 return ($ref||'SCALAR') . ('REF' x $n_steps);
1244 my ($self, $data) = @_;
1245 my @try = ($self->_refkind($data));
1246 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1247 push @try, 'FALLBACK';
1251 sub _METHOD_FOR_refkind {
1252 my ($self, $meth_prefix, $data) = @_;
1255 for (@{$self->_try_refkind($data)}) {
1256 $method = $self->can($meth_prefix."_".$_)
1260 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1264 sub _SWITCH_refkind {
1265 my ($self, $data, $dispatch_table) = @_;
1268 for (@{$self->_try_refkind($data)}) {
1269 $coderef = $dispatch_table->{$_}
1273 puke "no dispatch entry for ".$self->_refkind($data)
1282 #======================================================================
1283 # VALUES, GENERATE, AUTOLOAD
1284 #======================================================================
1286 # LDNOTE: original code from nwiger, didn't touch code in that section
1287 # I feel the AUTOLOAD stuff should not be the default, it should
1288 # only be activated on explicit demand by user.
1292 my $data = shift || return;
1293 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1294 unless ref $data eq 'HASH';
1297 foreach my $k (sort keys %$data) {
1298 my $v = $data->{$k};
1299 $self->_SWITCH_refkind($v, {
1301 if ($self->{array_datatypes}) { # array datatype
1302 push @all_bind, $self->_bindtype($k, $v);
1304 else { # literal SQL with bind
1305 my ($sql, @bind) = @$v;
1306 $self->_assert_bindval_matches_bindtype(@bind);
1307 push @all_bind, @bind;
1310 ARRAYREFREF => sub { # literal SQL with bind
1311 my ($sql, @bind) = @${$v};
1312 $self->_assert_bindval_matches_bindtype(@bind);
1313 push @all_bind, @bind;
1315 SCALARREF => sub { # literal SQL without bind
1317 SCALAR_or_UNDEF => sub {
1318 push @all_bind, $self->_bindtype($k, $v);
1329 my(@sql, @sqlq, @sqlv);
1333 if ($ref eq 'HASH') {
1334 for my $k (sort keys %$_) {
1337 my $label = $self->_quote($k);
1338 if ($r eq 'ARRAY') {
1339 # literal SQL with bind
1340 my ($sql, @bind) = @$v;
1341 $self->_assert_bindval_matches_bindtype(@bind);
1342 push @sqlq, "$label = $sql";
1344 } elsif ($r eq 'SCALAR') {
1345 # literal SQL without bind
1346 push @sqlq, "$label = $$v";
1348 push @sqlq, "$label = ?";
1349 push @sqlv, $self->_bindtype($k, $v);
1352 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1353 } elsif ($ref eq 'ARRAY') {
1354 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1357 if ($r eq 'ARRAY') { # literal SQL with bind
1358 my ($sql, @bind) = @$v;
1359 $self->_assert_bindval_matches_bindtype(@bind);
1362 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1363 # embedded literal SQL
1370 push @sql, '(' . join(', ', @sqlq) . ')';
1371 } elsif ($ref eq 'SCALAR') {
1375 # strings get case twiddled
1376 push @sql, $self->_sqlcase($_);
1380 my $sql = join ' ', @sql;
1382 # this is pretty tricky
1383 # if ask for an array, return ($stmt, @bind)
1384 # otherwise, s/?/shift @sqlv/ to put it inline
1386 return ($sql, @sqlv);
1388 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1389 ref $d ? $d->[1] : $d/e;
1398 # This allows us to check for a local, then _form, attr
1400 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1401 return $self->generate($name, @_);
1412 SQL::Abstract - Generate SQL from Perl data structures
1418 my $sql = SQL::Abstract->new;
1420 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1422 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1424 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1426 my($stmt, @bind) = $sql->delete($table, \%where);
1428 # Then, use these in your DBI statements
1429 my $sth = $dbh->prepare($stmt);
1430 $sth->execute(@bind);
1432 # Just generate the WHERE clause
1433 my($stmt, @bind) = $sql->where(\%where, $order);
1435 # Return values in the same order, for hashed queries
1436 # See PERFORMANCE section for more details
1437 my @bind = $sql->values(\%fieldvals);
1441 This module was inspired by the excellent L<DBIx::Abstract>.
1442 However, in using that module I found that what I really wanted
1443 to do was generate SQL, but still retain complete control over my
1444 statement handles and use the DBI interface. So, I set out to
1445 create an abstract SQL generation module.
1447 While based on the concepts used by L<DBIx::Abstract>, there are
1448 several important differences, especially when it comes to WHERE
1449 clauses. I have modified the concepts used to make the SQL easier
1450 to generate from Perl data structures and, IMO, more intuitive.
1451 The underlying idea is for this module to do what you mean, based
1452 on the data structures you provide it. The big advantage is that
1453 you don't have to modify your code every time your data changes,
1454 as this module figures it out.
1456 To begin with, an SQL INSERT is as easy as just specifying a hash
1457 of C<key=value> pairs:
1460 name => 'Jimbo Bobson',
1461 phone => '123-456-7890',
1462 address => '42 Sister Lane',
1463 city => 'St. Louis',
1464 state => 'Louisiana',
1467 The SQL can then be generated with this:
1469 my($stmt, @bind) = $sql->insert('people', \%data);
1471 Which would give you something like this:
1473 $stmt = "INSERT INTO people
1474 (address, city, name, phone, state)
1475 VALUES (?, ?, ?, ?, ?)";
1476 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1477 '123-456-7890', 'Louisiana');
1479 These are then used directly in your DBI code:
1481 my $sth = $dbh->prepare($stmt);
1482 $sth->execute(@bind);
1484 =head2 Inserting and Updating Arrays
1486 If your database has array types (like for example Postgres),
1487 activate the special option C<< array_datatypes => 1 >>
1488 when creating the C<SQL::Abstract> object.
1489 Then you may use an arrayref to insert and update database array types:
1491 my $sql = SQL::Abstract->new(array_datatypes => 1);
1493 planets => [qw/Mercury Venus Earth Mars/]
1496 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1500 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1502 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1505 =head2 Inserting and Updating SQL
1507 In order to apply SQL functions to elements of your C<%data> you may
1508 specify a reference to an arrayref for the given hash value. For example,
1509 if you need to execute the Oracle C<to_date> function on a value, you can
1510 say something like this:
1514 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1517 The first value in the array is the actual SQL. Any other values are
1518 optional and would be included in the bind values array. This gives
1521 my($stmt, @bind) = $sql->insert('people', \%data);
1523 $stmt = "INSERT INTO people (name, date_entered)
1524 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1525 @bind = ('Bill', '03/02/2003');
1527 An UPDATE is just as easy, all you change is the name of the function:
1529 my($stmt, @bind) = $sql->update('people', \%data);
1531 Notice that your C<%data> isn't touched; the module will generate
1532 the appropriately quirky SQL for you automatically. Usually you'll
1533 want to specify a WHERE clause for your UPDATE, though, which is
1534 where handling C<%where> hashes comes in handy...
1536 =head2 Complex where statements
1538 This module can generate pretty complicated WHERE statements
1539 easily. For example, simple C<key=value> pairs are taken to mean
1540 equality, and if you want to see if a field is within a set
1541 of values, you can use an arrayref. Let's say we wanted to
1542 SELECT some data based on this criteria:
1545 requestor => 'inna',
1546 worker => ['nwiger', 'rcwe', 'sfz'],
1547 status => { '!=', 'completed' }
1550 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1552 The above would give you something like this:
1554 $stmt = "SELECT * FROM tickets WHERE
1555 ( requestor = ? ) AND ( status != ? )
1556 AND ( worker = ? OR worker = ? OR worker = ? )";
1557 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1559 Which you could then use in DBI code like so:
1561 my $sth = $dbh->prepare($stmt);
1562 $sth->execute(@bind);
1568 The methods are simple. There's one for every major SQL operation,
1569 and a constructor you use first. The arguments are specified in a
1570 similar order for each method (table, then fields, then a where
1571 clause) to try and simplify things.
1573 =head2 new(option => 'value')
1575 The C<new()> function takes a list of options and values, and returns
1576 a new B<SQL::Abstract> object which can then be used to generate SQL
1577 through the methods below. The options accepted are:
1583 If set to 'lower', then SQL will be generated in all lowercase. By
1584 default SQL is generated in "textbook" case meaning something like:
1586 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1588 Any setting other than 'lower' is ignored.
1592 This determines what the default comparison operator is. By default
1593 it is C<=>, meaning that a hash like this:
1595 %where = (name => 'nwiger', email => 'nate@wiger.org');
1597 Will generate SQL like this:
1599 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1601 However, you may want loose comparisons by default, so if you set
1602 C<cmp> to C<like> you would get SQL such as:
1604 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1606 You can also override the comparison on an individual basis - see
1607 the huge section on L</"WHERE CLAUSES"> at the bottom.
1609 =item sqltrue, sqlfalse
1611 Expressions for inserting boolean values within SQL statements.
1612 By default these are C<1=1> and C<1=0>. They are used
1613 by the special operators C<-in> and C<-not_in> for generating
1614 correct SQL even when the argument is an empty array (see below).
1618 This determines the default logical operator for multiple WHERE
1619 statements in arrays or hashes. If absent, the default logic is "or"
1620 for arrays, and "and" for hashes. This means that a WHERE
1624 event_date => {'>=', '2/13/99'},
1625 event_date => {'<=', '4/24/03'},
1628 will generate SQL like this:
1630 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1632 This is probably not what you want given this query, though (look
1633 at the dates). To change the "OR" to an "AND", simply specify:
1635 my $sql = SQL::Abstract->new(logic => 'and');
1637 Which will change the above C<WHERE> to:
1639 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1641 The logic can also be changed locally by inserting
1642 a modifier in front of an arrayref:
1644 @where = (-and => [event_date => {'>=', '2/13/99'},
1645 event_date => {'<=', '4/24/03'} ]);
1647 See the L</"WHERE CLAUSES"> section for explanations.
1651 This will automatically convert comparisons using the specified SQL
1652 function for both column and value. This is mostly used with an argument
1653 of C<upper> or C<lower>, so that the SQL will have the effect of
1654 case-insensitive "searches". For example, this:
1656 $sql = SQL::Abstract->new(convert => 'upper');
1657 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1659 Will turn out the following SQL:
1661 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1663 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1664 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1665 not validate this option; it will just pass through what you specify verbatim).
1669 This is a kludge because many databases suck. For example, you can't
1670 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1671 Instead, you have to use C<bind_param()>:
1673 $sth->bind_param(1, 'reg data');
1674 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1676 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1677 which loses track of which field each slot refers to. Fear not.
1679 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1680 Currently, you can specify either C<normal> (default) or C<columns>. If you
1681 specify C<columns>, you will get an array that looks like this:
1683 my $sql = SQL::Abstract->new(bindtype => 'columns');
1684 my($stmt, @bind) = $sql->insert(...);
1687 [ 'column1', 'value1' ],
1688 [ 'column2', 'value2' ],
1689 [ 'column3', 'value3' ],
1692 You can then iterate through this manually, using DBI's C<bind_param()>.
1694 $sth->prepare($stmt);
1697 my($col, $data) = @$_;
1698 if ($col eq 'details' || $col eq 'comments') {
1699 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1700 } elsif ($col eq 'image') {
1701 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1703 $sth->bind_param($i, $data);
1707 $sth->execute; # execute without @bind now
1709 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1710 Basically, the advantage is still that you don't have to care which fields
1711 are or are not included. You could wrap that above C<for> loop in a simple
1712 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1713 get a layer of abstraction over manual SQL specification.
1715 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1716 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1717 will expect the bind values in this format.
1721 This is the character that a table or column name will be quoted
1722 with. By default this is an empty string, but you could set it to
1723 the character C<`>, to generate SQL like this:
1725 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1727 Alternatively, you can supply an array ref of two items, the first being the left
1728 hand quote character, and the second the right hand quote character. For
1729 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1730 that generates SQL like this:
1732 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1734 Quoting is useful if you have tables or columns names that are reserved
1735 words in your database's SQL dialect.
1739 This is the character that will be used to escape L</quote_char>s appearing
1740 in an identifier before it has been quoted.
1742 The parameter default in case of a single L</quote_char> character is the quote
1745 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1746 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1747 of the B<opening (left)> L</quote_char> within the identifier are currently left
1748 untouched. The default for opening-closing-style quotes may change in future
1749 versions, thus you are B<strongly encouraged> to specify the escape character
1754 This is the character that separates a table and column name. It is
1755 necessary to specify this when the C<quote_char> option is selected,
1756 so that tables and column names can be individually quoted like this:
1758 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1760 =item injection_guard
1762 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1763 column name specified in a query structure. This is a safety mechanism to avoid
1764 injection attacks when mishandling user input e.g.:
1766 my %condition_as_column_value_pairs = get_values_from_user();
1767 $sqla->select( ... , \%condition_as_column_value_pairs );
1769 If the expression matches an exception is thrown. Note that literal SQL
1770 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1772 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1774 =item array_datatypes
1776 When this option is true, arrayrefs in INSERT or UPDATE are
1777 interpreted as array datatypes and are passed directly
1779 When this option is false, arrayrefs are interpreted
1780 as literal SQL, just like refs to arrayrefs
1781 (but this behavior is for backwards compatibility; when writing
1782 new queries, use the "reference to arrayref" syntax
1788 Takes a reference to a list of "special operators"
1789 to extend the syntax understood by L<SQL::Abstract>.
1790 See section L</"SPECIAL OPERATORS"> for details.
1794 Takes a reference to a list of "unary operators"
1795 to extend the syntax understood by L<SQL::Abstract>.
1796 See section L</"UNARY OPERATORS"> for details.
1802 =head2 insert($table, \@values || \%fieldvals, \%options)
1804 This is the simplest function. You simply give it a table name
1805 and either an arrayref of values or hashref of field/value pairs.
1806 It returns an SQL INSERT statement and a list of bind values.
1807 See the sections on L</"Inserting and Updating Arrays"> and
1808 L</"Inserting and Updating SQL"> for information on how to insert
1809 with those data types.
1811 The optional C<\%options> hash reference may contain additional
1812 options to generate the insert SQL. Currently supported options
1819 Takes either a scalar of raw SQL fields, or an array reference of
1820 field names, and adds on an SQL C<RETURNING> statement at the end.
1821 This allows you to return data generated by the insert statement
1822 (such as row IDs) without performing another C<SELECT> statement.
1823 Note, however, this is not part of the SQL standard and may not
1824 be supported by all database engines.
1828 =head2 update($table, \%fieldvals, \%where, \%options)
1830 This takes a table, hashref of field/value pairs, and an optional
1831 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1833 See the sections on L</"Inserting and Updating Arrays"> and
1834 L</"Inserting and Updating SQL"> for information on how to insert
1835 with those data types.
1837 The optional C<\%options> hash reference may contain additional
1838 options to generate the update SQL. Currently supported options
1845 See the C<returning> option to
1846 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1850 =head2 select($source, $fields, $where, $order)
1852 This returns a SQL SELECT statement and associated list of bind values, as
1853 specified by the arguments:
1859 Specification of the 'FROM' part of the statement.
1860 The argument can be either a plain scalar (interpreted as a table
1861 name, will be quoted), or an arrayref (interpreted as a list
1862 of table names, joined by commas, quoted), or a scalarref
1863 (literal SQL, not quoted).
1867 Specification of the list of fields to retrieve from
1869 The argument can be either an arrayref (interpreted as a list
1870 of field names, will be joined by commas and quoted), or a
1871 plain scalar (literal SQL, not quoted).
1872 Please observe that this API is not as flexible as that of
1873 the first argument C<$source>, for backwards compatibility reasons.
1877 Optional argument to specify the WHERE part of the query.
1878 The argument is most often a hashref, but can also be
1879 an arrayref or plain scalar --
1880 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1884 Optional argument to specify the ORDER BY part of the query.
1885 The argument can be a scalar, a hashref or an arrayref
1886 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1892 =head2 delete($table, \%where, \%options)
1894 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1895 It returns an SQL DELETE statement and list of bind values.
1897 The optional C<\%options> hash reference may contain additional
1898 options to generate the delete SQL. Currently supported options
1905 See the C<returning> option to
1906 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1910 =head2 where(\%where, $order)
1912 This is used to generate just the WHERE clause. For example,
1913 if you have an arbitrary data structure and know what the
1914 rest of your SQL is going to look like, but want an easy way
1915 to produce a WHERE clause, use this. It returns an SQL WHERE
1916 clause and list of bind values.
1919 =head2 values(\%data)
1921 This just returns the values from the hash C<%data>, in the same
1922 order that would be returned from any of the other above queries.
1923 Using this allows you to markedly speed up your queries if you
1924 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1926 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1928 Warning: This is an experimental method and subject to change.
1930 This returns arbitrarily generated SQL. It's a really basic shortcut.
1931 It will return two different things, depending on return context:
1933 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1934 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1936 These would return the following:
1938 # First calling form
1939 $stmt = "CREATE TABLE test (?, ?)";
1940 @bind = (field1, field2);
1942 # Second calling form
1943 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1945 Depending on what you're trying to do, it's up to you to choose the correct
1946 format. In this example, the second form is what you would want.
1950 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1954 ALTER SESSION SET nls_date_format = 'MM/YY'
1956 You get the idea. Strings get their case twiddled, but everything
1957 else remains verbatim.
1959 =head1 EXPORTABLE FUNCTIONS
1961 =head2 is_plain_value
1963 Determines if the supplied argument is a plain value as understood by this
1968 =item * The value is C<undef>
1970 =item * The value is a non-reference
1972 =item * The value is an object with stringification overloading
1974 =item * The value is of the form C<< { -value => $anything } >>
1978 On failure returns C<undef>, on success returns a B<scalar> reference
1979 to the original supplied argument.
1985 The stringification overloading detection is rather advanced: it takes
1986 into consideration not only the presence of a C<""> overload, but if that
1987 fails also checks for enabled
1988 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1989 on either C<0+> or C<bool>.
1991 Unfortunately testing in the field indicates that this
1992 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1993 but only when very large numbers of stringifying objects are involved.
1994 At the time of writing ( Sep 2014 ) there is no clear explanation of
1995 the direct cause, nor is there a manageably small test case that reliably
1996 reproduces the problem.
1998 If you encounter any of the following exceptions in B<random places within
1999 your application stack> - this module may be to blame:
2001 Operation "ne": no method found,
2002 left argument in overloaded package <something>,
2003 right argument in overloaded package <something>
2007 Stub found while resolving method "???" overloading """" in package <something>
2009 If you fall victim to the above - please attempt to reduce the problem
2010 to something that could be sent to the L<SQL::Abstract developers
2011 |DBIx::Class/GETTING HELP/SUPPORT>
2012 (either publicly or privately). As a workaround in the meantime you can
2013 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2014 value, which will most likely eliminate your problem (at the expense of
2015 not being able to properly detect exotic forms of stringification).
2017 This notice and environment variable will be removed in a future version,
2018 as soon as the underlying problem is found and a reliable workaround is
2023 =head2 is_literal_value
2025 Determines if the supplied argument is a literal value as understood by this
2030 =item * C<\$sql_string>
2032 =item * C<\[ $sql_string, @bind_values ]>
2036 On failure returns C<undef>, on success returns an B<array> reference
2037 containing the unpacked version of the supplied literal SQL and bind values.
2039 =head1 WHERE CLAUSES
2043 This module uses a variation on the idea from L<DBIx::Abstract>. It
2044 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2045 module is that things in arrays are OR'ed, and things in hashes
2048 The easiest way to explain is to show lots of examples. After
2049 each C<%where> hash shown, it is assumed you used:
2051 my($stmt, @bind) = $sql->where(\%where);
2053 However, note that the C<%where> hash can be used directly in any
2054 of the other functions as well, as described above.
2056 =head2 Key-value pairs
2058 So, let's get started. To begin, a simple hash:
2062 status => 'completed'
2065 Is converted to SQL C<key = val> statements:
2067 $stmt = "WHERE user = ? AND status = ?";
2068 @bind = ('nwiger', 'completed');
2070 One common thing I end up doing is having a list of values that
2071 a field can be in. To do this, simply specify a list inside of
2076 status => ['assigned', 'in-progress', 'pending'];
2079 This simple code will create the following:
2081 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2082 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2084 A field associated to an empty arrayref will be considered a
2085 logical false and will generate 0=1.
2087 =head2 Tests for NULL values
2089 If the value part is C<undef> then this is converted to SQL <IS NULL>
2098 $stmt = "WHERE user = ? AND status IS NULL";
2101 To test if a column IS NOT NULL:
2105 status => { '!=', undef },
2108 =head2 Specific comparison operators
2110 If you want to specify a different type of operator for your comparison,
2111 you can use a hashref for a given column:
2115 status => { '!=', 'completed' }
2118 Which would generate:
2120 $stmt = "WHERE user = ? AND status != ?";
2121 @bind = ('nwiger', 'completed');
2123 To test against multiple values, just enclose the values in an arrayref:
2125 status => { '=', ['assigned', 'in-progress', 'pending'] };
2127 Which would give you:
2129 "WHERE status = ? OR status = ? OR status = ?"
2132 The hashref can also contain multiple pairs, in which case it is expanded
2133 into an C<AND> of its elements:
2137 status => { '!=', 'completed', -not_like => 'pending%' }
2140 # Or more dynamically, like from a form
2141 $where{user} = 'nwiger';
2142 $where{status}{'!='} = 'completed';
2143 $where{status}{'-not_like'} = 'pending%';
2145 # Both generate this
2146 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2147 @bind = ('nwiger', 'completed', 'pending%');
2150 To get an OR instead, you can combine it with the arrayref idea:
2154 priority => [ { '=', 2 }, { '>', 5 } ]
2157 Which would generate:
2159 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2160 @bind = ('2', '5', 'nwiger');
2162 If you want to include literal SQL (with or without bind values), just use a
2163 scalar reference or reference to an arrayref as the value:
2166 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2167 date_expires => { '<' => \"now()" }
2170 Which would generate:
2172 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2173 @bind = ('11/26/2008');
2176 =head2 Logic and nesting operators
2178 In the example above,
2179 there is a subtle trap if you want to say something like
2180 this (notice the C<AND>):
2182 WHERE priority != ? AND priority != ?
2184 Because, in Perl you I<can't> do this:
2186 priority => { '!=' => 2, '!=' => 1 }
2188 As the second C<!=> key will obliterate the first. The solution
2189 is to use the special C<-modifier> form inside an arrayref:
2191 priority => [ -and => {'!=', 2},
2195 Normally, these would be joined by C<OR>, but the modifier tells it
2196 to use C<AND> instead. (Hint: You can use this in conjunction with the
2197 C<logic> option to C<new()> in order to change the way your queries
2198 work by default.) B<Important:> Note that the C<-modifier> goes
2199 B<INSIDE> the arrayref, as an extra first element. This will
2200 B<NOT> do what you think it might:
2202 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2204 Here is a quick list of equivalencies, since there is some overlap:
2207 status => {'!=', 'completed', 'not like', 'pending%' }
2208 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2211 status => {'=', ['assigned', 'in-progress']}
2212 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2213 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2217 =head2 Special operators: IN, BETWEEN, etc.
2219 You can also use the hashref format to compare a list of fields using the
2220 C<IN> comparison operator, by specifying the list as an arrayref:
2223 status => 'completed',
2224 reportid => { -in => [567, 2335, 2] }
2227 Which would generate:
2229 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2230 @bind = ('completed', '567', '2335', '2');
2232 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2235 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2236 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2237 'sqltrue' (by default: C<1=1>).
2239 In addition to the array you can supply a chunk of literal sql or
2240 literal sql with bind:
2243 customer => { -in => \[
2244 'SELECT cust_id FROM cust WHERE balance > ?',
2247 status => { -in => \'SELECT status_codes FROM states' },
2253 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2254 AND status IN ( SELECT status_codes FROM states )
2258 Finally, if the argument to C<-in> is not a reference, it will be
2259 treated as a single-element array.
2261 Another pair of operators is C<-between> and C<-not_between>,
2262 used with an arrayref of two values:
2266 completion_date => {
2267 -not_between => ['2002-10-01', '2003-02-06']
2273 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2275 Just like with C<-in> all plausible combinations of literal SQL
2279 start0 => { -between => [ 1, 2 ] },
2280 start1 => { -between => \["? AND ?", 1, 2] },
2281 start2 => { -between => \"lower(x) AND upper(y)" },
2282 start3 => { -between => [
2284 \["upper(?)", 'stuff' ],
2291 ( start0 BETWEEN ? AND ? )
2292 AND ( start1 BETWEEN ? AND ? )
2293 AND ( start2 BETWEEN lower(x) AND upper(y) )
2294 AND ( start3 BETWEEN lower(x) AND upper(?) )
2296 @bind = (1, 2, 1, 2, 'stuff');
2299 These are the two builtin "special operators"; but the
2300 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2302 =head2 Unary operators: bool
2304 If you wish to test against boolean columns or functions within your
2305 database you can use the C<-bool> and C<-not_bool> operators. For
2306 example to test the column C<is_user> being true and the column
2307 C<is_enabled> being false you would use:-
2311 -not_bool => 'is_enabled',
2316 WHERE is_user AND NOT is_enabled
2318 If a more complex combination is required, testing more conditions,
2319 then you should use the and/or operators:-
2324 -not_bool => { two=> { -rlike => 'bar' } },
2325 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2336 (NOT ( three = ? OR three > ? ))
2339 =head2 Nested conditions, -and/-or prefixes
2341 So far, we've seen how multiple conditions are joined with a top-level
2342 C<AND>. We can change this by putting the different conditions we want in
2343 hashes and then putting those hashes in an array. For example:
2348 status => { -like => ['pending%', 'dispatched'] },
2352 status => 'unassigned',
2356 This data structure would create the following:
2358 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2359 OR ( user = ? AND status = ? ) )";
2360 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2363 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2364 to change the logic inside:
2370 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2371 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2378 $stmt = "WHERE ( user = ?
2379 AND ( ( workhrs > ? AND geo = ? )
2380 OR ( workhrs < ? OR geo = ? ) ) )";
2381 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2383 =head3 Algebraic inconsistency, for historical reasons
2385 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2386 operator goes C<outside> of the nested structure; whereas when connecting
2387 several constraints on one column, the C<-and> operator goes
2388 C<inside> the arrayref. Here is an example combining both features:
2391 -and => [a => 1, b => 2],
2392 -or => [c => 3, d => 4],
2393 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2398 WHERE ( ( ( a = ? AND b = ? )
2399 OR ( c = ? OR d = ? )
2400 OR ( e LIKE ? AND e LIKE ? ) ) )
2402 This difference in syntax is unfortunate but must be preserved for
2403 historical reasons. So be careful: the two examples below would
2404 seem algebraically equivalent, but they are not
2407 { -like => 'foo%' },
2408 { -like => '%bar' },
2410 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2413 { col => { -like => 'foo%' } },
2414 { col => { -like => '%bar' } },
2416 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2419 =head2 Literal SQL and value type operators
2421 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2422 side" is a column name and the "right side" is a value (normally rendered as
2423 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2424 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2425 alter this behavior. There are several ways of doing so.
2429 This is a virtual operator that signals the string to its right side is an
2430 identifier (a column name) and not a value. For example to compare two
2431 columns you would write:
2434 priority => { '<', 2 },
2435 requestor => { -ident => 'submitter' },
2440 $stmt = "WHERE priority < ? AND requestor = submitter";
2443 If you are maintaining legacy code you may see a different construct as
2444 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2449 This is a virtual operator that signals that the construct to its right side
2450 is a value to be passed to DBI. This is for example necessary when you want
2451 to write a where clause against an array (for RDBMS that support such
2452 datatypes). For example:
2455 array => { -value => [1, 2, 3] }
2460 $stmt = 'WHERE array = ?';
2461 @bind = ([1, 2, 3]);
2463 Note that if you were to simply say:
2469 the result would probably not be what you wanted:
2471 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2476 Finally, sometimes only literal SQL will do. To include a random snippet
2477 of SQL verbatim, you specify it as a scalar reference. Consider this only
2478 as a last resort. Usually there is a better way. For example:
2481 priority => { '<', 2 },
2482 requestor => { -in => \'(SELECT name FROM hitmen)' },
2487 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2490 Note that in this example, you only get one bind parameter back, since
2491 the verbatim SQL is passed as part of the statement.
2495 Never use untrusted input as a literal SQL argument - this is a massive
2496 security risk (there is no way to check literal snippets for SQL
2497 injections and other nastyness). If you need to deal with untrusted input
2498 use literal SQL with placeholders as described next.
2500 =head3 Literal SQL with placeholders and bind values (subqueries)
2502 If the literal SQL to be inserted has placeholders and bind values,
2503 use a reference to an arrayref (yes this is a double reference --
2504 not so common, but perfectly legal Perl). For example, to find a date
2505 in Postgres you can use something like this:
2508 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2513 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2516 Note that you must pass the bind values in the same format as they are returned
2517 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2518 to C<columns>, you must provide the bind values in the
2519 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2520 scalar value; most commonly the column name, but you can use any scalar value
2521 (including references and blessed references), L<SQL::Abstract> will simply
2522 pass it through intact. So if C<bindtype> is set to C<columns> the above
2523 example will look like:
2526 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2529 Literal SQL is especially useful for nesting parenthesized clauses in the
2530 main SQL query. Here is a first example:
2532 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2536 bar => \["IN ($sub_stmt)" => @sub_bind],
2541 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2542 WHERE c2 < ? AND c3 LIKE ?))";
2543 @bind = (1234, 100, "foo%");
2545 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2546 are expressed in the same way. Of course the C<$sub_stmt> and
2547 its associated bind values can be generated through a former call
2550 my ($sub_stmt, @sub_bind)
2551 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2552 c3 => {-like => "foo%"}});
2555 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2558 In the examples above, the subquery was used as an operator on a column;
2559 but the same principle also applies for a clause within the main C<%where>
2560 hash, like an EXISTS subquery:
2562 my ($sub_stmt, @sub_bind)
2563 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2564 my %where = ( -and => [
2566 \["EXISTS ($sub_stmt)" => @sub_bind],
2571 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2572 WHERE c1 = ? AND c2 > t0.c0))";
2576 Observe that the condition on C<c2> in the subquery refers to
2577 column C<t0.c0> of the main query: this is I<not> a bind
2578 value, so we have to express it through a scalar ref.
2579 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2580 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2581 what we wanted here.
2583 Finally, here is an example where a subquery is used
2584 for expressing unary negation:
2586 my ($sub_stmt, @sub_bind)
2587 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2588 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2590 lname => {like => '%son%'},
2591 \["NOT ($sub_stmt)" => @sub_bind],
2596 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2597 @bind = ('%son%', 10, 20)
2599 =head3 Deprecated usage of Literal SQL
2601 Below are some examples of archaic use of literal SQL. It is shown only as
2602 reference for those who deal with legacy code. Each example has a much
2603 better, cleaner and safer alternative that users should opt for in new code.
2609 my %where = ( requestor => \'IS NOT NULL' )
2611 $stmt = "WHERE requestor IS NOT NULL"
2613 This used to be the way of generating NULL comparisons, before the handling
2614 of C<undef> got formalized. For new code please use the superior syntax as
2615 described in L</Tests for NULL values>.
2619 my %where = ( requestor => \'= submitter' )
2621 $stmt = "WHERE requestor = submitter"
2623 This used to be the only way to compare columns. Use the superior L</-ident>
2624 method for all new code. For example an identifier declared in such a way
2625 will be properly quoted if L</quote_char> is properly set, while the legacy
2626 form will remain as supplied.
2630 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2632 $stmt = "WHERE completed > ? AND is_ready"
2633 @bind = ('2012-12-21')
2635 Using an empty string literal used to be the only way to express a boolean.
2636 For all new code please use the much more readable
2637 L<-bool|/Unary operators: bool> operator.
2643 These pages could go on for a while, since the nesting of the data
2644 structures this module can handle are pretty much unlimited (the
2645 module implements the C<WHERE> expansion as a recursive function
2646 internally). Your best bet is to "play around" with the module a
2647 little to see how the data structures behave, and choose the best
2648 format for your data based on that.
2650 And of course, all the values above will probably be replaced with
2651 variables gotten from forms or the command line. After all, if you
2652 knew everything ahead of time, you wouldn't have to worry about
2653 dynamically-generating SQL and could just hardwire it into your
2656 =head1 ORDER BY CLAUSES
2658 Some functions take an order by clause. This can either be a scalar (just a
2659 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2660 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2663 Given | Will Generate
2664 ---------------------------------------------------------------
2666 'colA' | ORDER BY colA
2668 [qw/colA colB/] | ORDER BY colA, colB
2670 {-asc => 'colA'} | ORDER BY colA ASC
2672 {-desc => 'colB'} | ORDER BY colB DESC
2674 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2676 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2678 \'colA DESC' | ORDER BY colA DESC
2680 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2681 | /* ...with $x bound to ? */
2684 { -asc => 'colA' }, | colA ASC,
2685 { -desc => [qw/colB/] }, | colB DESC,
2686 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2687 \'colE DESC', | colE DESC,
2688 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2689 ] | /* ...with $x bound to ? */
2690 ===============================================================
2694 =head1 SPECIAL OPERATORS
2696 my $sqlmaker = SQL::Abstract->new(special_ops => [
2700 my ($self, $field, $op, $arg) = @_;
2706 handler => 'method_name',
2710 A "special operator" is a SQL syntactic clause that can be
2711 applied to a field, instead of a usual binary operator.
2714 WHERE field IN (?, ?, ?)
2715 WHERE field BETWEEN ? AND ?
2716 WHERE MATCH(field) AGAINST (?, ?)
2718 Special operators IN and BETWEEN are fairly standard and therefore
2719 are builtin within C<SQL::Abstract> (as the overridable methods
2720 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2721 like the MATCH .. AGAINST example above which is specific to MySQL,
2722 you can write your own operator handlers - supply a C<special_ops>
2723 argument to the C<new> method. That argument takes an arrayref of
2724 operator definitions; each operator definition is a hashref with two
2731 the regular expression to match the operator
2735 Either a coderef or a plain scalar method name. In both cases
2736 the expected return is C<< ($sql, @bind) >>.
2738 When supplied with a method name, it is simply called on the
2739 L<SQL::Abstract> object as:
2741 $self->$method_name($field, $op, $arg)
2745 $field is the LHS of the operator
2746 $op is the part that matched the handler regex
2749 When supplied with a coderef, it is called as:
2751 $coderef->($self, $field, $op, $arg)
2756 For example, here is an implementation
2757 of the MATCH .. AGAINST syntax for MySQL
2759 my $sqlmaker = SQL::Abstract->new(special_ops => [
2761 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2762 {regex => qr/^match$/i,
2764 my ($self, $field, $op, $arg) = @_;
2765 $arg = [$arg] if not ref $arg;
2766 my $label = $self->_quote($field);
2767 my ($placeholder) = $self->_convert('?');
2768 my $placeholders = join ", ", (($placeholder) x @$arg);
2769 my $sql = $self->_sqlcase('match') . " ($label) "
2770 . $self->_sqlcase('against') . " ($placeholders) ";
2771 my @bind = $self->_bindtype($field, @$arg);
2772 return ($sql, @bind);
2779 =head1 UNARY OPERATORS
2781 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2785 my ($self, $op, $arg) = @_;
2791 handler => 'method_name',
2795 A "unary operator" is a SQL syntactic clause that can be
2796 applied to a field - the operator goes before the field
2798 You can write your own operator handlers - supply a C<unary_ops>
2799 argument to the C<new> method. That argument takes an arrayref of
2800 operator definitions; each operator definition is a hashref with two
2807 the regular expression to match the operator
2811 Either a coderef or a plain scalar method name. In both cases
2812 the expected return is C<< $sql >>.
2814 When supplied with a method name, it is simply called on the
2815 L<SQL::Abstract> object as:
2817 $self->$method_name($op, $arg)
2821 $op is the part that matched the handler regex
2822 $arg is the RHS or argument of the operator
2824 When supplied with a coderef, it is called as:
2826 $coderef->($self, $op, $arg)
2834 Thanks to some benchmarking by Mark Stosberg, it turns out that
2835 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2836 I must admit this wasn't an intentional design issue, but it's a
2837 byproduct of the fact that you get to control your C<DBI> handles
2840 To maximize performance, use a code snippet like the following:
2842 # prepare a statement handle using the first row
2843 # and then reuse it for the rest of the rows
2845 for my $href (@array_of_hashrefs) {
2846 $stmt ||= $sql->insert('table', $href);
2847 $sth ||= $dbh->prepare($stmt);
2848 $sth->execute($sql->values($href));
2851 The reason this works is because the keys in your C<$href> are sorted
2852 internally by B<SQL::Abstract>. Thus, as long as your data retains
2853 the same structure, you only have to generate the SQL the first time
2854 around. On subsequent queries, simply use the C<values> function provided
2855 by this module to return your values in the correct order.
2857 However this depends on the values having the same type - if, for
2858 example, the values of a where clause may either have values
2859 (resulting in sql of the form C<column = ?> with a single bind
2860 value), or alternatively the values might be C<undef> (resulting in
2861 sql of the form C<column IS NULL> with no bind value) then the
2862 caching technique suggested will not work.
2866 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2867 really like this part (I do, at least). Building up a complex query
2868 can be as simple as the following:
2875 use CGI::FormBuilder;
2878 my $form = CGI::FormBuilder->new(...);
2879 my $sql = SQL::Abstract->new;
2881 if ($form->submitted) {
2882 my $field = $form->field;
2883 my $id = delete $field->{id};
2884 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2887 Of course, you would still have to connect using C<DBI> to run the
2888 query, but the point is that if you make your form look like your
2889 table, the actual query script can be extremely simplistic.
2891 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2892 a fast interface to returning and formatting data. I frequently
2893 use these three modules together to write complex database query
2894 apps in under 50 lines.
2896 =head1 HOW TO CONTRIBUTE
2898 Contributions are always welcome, in all usable forms (we especially
2899 welcome documentation improvements). The delivery methods include git-
2900 or unified-diff formatted patches, GitHub pull requests, or plain bug
2901 reports either via RT or the Mailing list. Contributors are generally
2902 granted full access to the official repository after their first several
2903 patches pass successful review.
2905 This project is maintained in a git repository. The code and related tools are
2906 accessible at the following locations:
2910 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2912 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2914 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2916 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2922 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2923 Great care has been taken to preserve the I<published> behavior
2924 documented in previous versions in the 1.* family; however,
2925 some features that were previously undocumented, or behaved
2926 differently from the documentation, had to be changed in order
2927 to clarify the semantics. Hence, client code that was relying
2928 on some dark areas of C<SQL::Abstract> v1.*
2929 B<might behave differently> in v1.50.
2931 The main changes are:
2937 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2941 support for the { operator => \"..." } construct (to embed literal SQL)
2945 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2949 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2953 defensive programming: check arguments
2957 fixed bug with global logic, which was previously implemented
2958 through global variables yielding side-effects. Prior versions would
2959 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2960 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2961 Now this is interpreted
2962 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2967 fixed semantics of _bindtype on array args
2971 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2972 we just avoid shifting arrays within that tree.
2976 dropped the C<_modlogic> function
2980 =head1 ACKNOWLEDGEMENTS
2982 There are a number of individuals that have really helped out with
2983 this module. Unfortunately, most of them submitted bugs via CPAN
2984 so I have no idea who they are! But the people I do know are:
2986 Ash Berlin (order_by hash term support)
2987 Matt Trout (DBIx::Class support)
2988 Mark Stosberg (benchmarking)
2989 Chas Owens (initial "IN" operator support)
2990 Philip Collins (per-field SQL functions)
2991 Eric Kolve (hashref "AND" support)
2992 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2993 Dan Kubb (support for "quote_char" and "name_sep")
2994 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2995 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2996 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2997 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2998 Oliver Charles (support for "RETURNING" after "INSERT")
3004 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3008 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3010 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3012 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3013 While not an official support venue, C<DBIx::Class> makes heavy use of
3014 C<SQL::Abstract>, and as such list members there are very familiar with
3015 how to create queries.
3019 This module is free software; you may copy this under the same
3020 terms as perl itself (either the GNU General Public License or
3021 the Artistic License)