1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.87';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
188 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
192 $opt{expand_unary} = {};
194 return bless \%opt, $class;
197 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
198 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
200 sub _assert_pass_injection_guard {
201 if ($_[1] =~ $_[0]->{injection_guard}) {
202 my $class = ref $_[0];
203 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
204 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
205 . "{injection_guard} attribute to ${class}->new()"
210 #======================================================================
212 #======================================================================
216 my $table = $self->_table(shift);
217 my $data = shift || return;
220 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
221 my ($sql, @bind) = $self->$method($data);
222 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
224 if ($options->{returning}) {
225 my ($s, @b) = $self->_insert_returning($options);
230 return wantarray ? ($sql, @bind) : $sql;
233 # So that subclasses can override INSERT ... RETURNING separately from
234 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
235 sub _insert_returning { shift->_returning(@_) }
238 my ($self, $options) = @_;
240 my $f = $options->{returning};
242 my ($sql, @bind) = $self->render_aqt(
243 $self->_expand_maybe_list_expr($f, undef, -ident)
246 ? $self->_sqlcase(' returning ') . $sql
247 : ($self->_sqlcase(' returning ').$sql, @bind);
250 sub _insert_HASHREF { # explicit list of fields and then values
251 my ($self, $data) = @_;
253 my @fields = sort keys %$data;
255 my ($sql, @bind) = $self->_insert_values($data);
258 $_ = $self->_quote($_) foreach @fields;
259 $sql = "( ".join(", ", @fields).") ".$sql;
261 return ($sql, @bind);
264 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
265 my ($self, $data) = @_;
267 # no names (arrayref) so can't generate bindtype
268 $self->{bindtype} ne 'columns'
269 or belch "can't do 'columns' bindtype when called with arrayref";
271 my (@values, @all_bind);
272 foreach my $value (@$data) {
273 my ($values, @bind) = $self->_insert_value(undef, $value);
274 push @values, $values;
275 push @all_bind, @bind;
277 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
278 return ($sql, @all_bind);
281 sub _insert_ARRAYREFREF { # literal SQL with bind
282 my ($self, $data) = @_;
284 my ($sql, @bind) = @${$data};
285 $self->_assert_bindval_matches_bindtype(@bind);
287 return ($sql, @bind);
291 sub _insert_SCALARREF { # literal SQL without bind
292 my ($self, $data) = @_;
298 my ($self, $data) = @_;
300 my (@values, @all_bind);
301 foreach my $column (sort keys %$data) {
302 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
303 push @values, $values;
304 push @all_bind, @bind;
306 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
307 return ($sql, @all_bind);
311 my ($self, $column, $v) = @_;
313 return $self->render_aqt(
314 $self->_expand_insert_value($column, $v)
318 sub _expand_insert_value {
319 my ($self, $column, $v) = @_;
321 if (ref($v) eq 'ARRAY') {
322 if ($self->{array_datatypes}) {
323 return +{ -bind => [ $column, $v ] };
325 my ($sql, @bind) = @$v;
326 $self->_assert_bindval_matches_bindtype(@bind);
327 return +{ -literal => $v };
329 if (ref($v) eq 'HASH') {
330 if (grep !/^-/, keys %$v) {
331 belch "HASH ref as bind value in insert is not supported";
332 return +{ -bind => [ $column, $v ] };
336 return +{ -bind => [ $column, undef ] };
338 local our $Cur_Col_Meta = $column;
339 return $self->expand_expr($v);
344 #======================================================================
346 #======================================================================
351 my $table = $self->_table(shift);
352 my $data = shift || return;
356 # first build the 'SET' part of the sql statement
357 puke "Unsupported data type specified to \$sql->update"
358 unless ref $data eq 'HASH';
360 my ($sql, @all_bind) = $self->_update_set_values($data);
361 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
365 my($where_sql, @where_bind) = $self->where($where);
367 push @all_bind, @where_bind;
370 if ($options->{returning}) {
371 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
372 $sql .= $returning_sql;
373 push @all_bind, @returning_bind;
376 return wantarray ? ($sql, @all_bind) : $sql;
379 sub _update_set_values {
380 my ($self, $data) = @_;
382 return $self->render_aqt(
383 $self->_expand_update_set_values($data),
387 sub _expand_update_set_values {
388 my ($self, $data) = @_;
389 $self->_expand_maybe_list_expr( [
392 $set = { -bind => $_ } unless defined $set;
393 +{ -op => [ '=', { -ident => $k }, $set ] };
399 ? ($self->{array_datatypes}
400 ? [ $k, +{ -bind => [ $k, $v ] } ]
401 : [ $k, +{ -literal => $v } ])
403 local our $Cur_Col_Meta = $k;
404 [ $k, $self->_expand_expr($v) ]
411 # So that subclasses can override UPDATE ... RETURNING separately from
413 sub _update_returning { shift->_returning(@_) }
417 #======================================================================
419 #======================================================================
424 my $table = $self->_table(shift);
425 my $fields = shift || '*';
429 my ($fields_sql, @bind) = $self->_select_fields($fields);
431 my ($where_sql, @where_bind) = $self->where($where, $order);
432 push @bind, @where_bind;
434 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
435 $self->_sqlcase('from'), $table)
438 return wantarray ? ($sql, @bind) : $sql;
442 my ($self, $fields) = @_;
443 return $fields unless ref($fields);
444 return $self->render_aqt(
445 $self->_expand_maybe_list_expr($fields, undef, '-ident')
449 #======================================================================
451 #======================================================================
456 my $table = $self->_table(shift);
460 my($where_sql, @bind) = $self->where($where);
461 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
463 if ($options->{returning}) {
464 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
465 $sql .= $returning_sql;
466 push @bind, @returning_bind;
469 return wantarray ? ($sql, @bind) : $sql;
472 # So that subclasses can override DELETE ... RETURNING separately from
474 sub _delete_returning { shift->_returning(@_) }
478 #======================================================================
480 #======================================================================
484 # Finally, a separate routine just to handle WHERE clauses
486 my ($self, $where, $order) = @_;
488 local $self->{convert_where} = $self->{convert};
491 my ($sql, @bind) = defined($where)
492 ? $self->_recurse_where($where)
494 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
498 my ($order_sql, @order_bind) = $self->_order_by($order);
500 push @bind, @order_bind;
503 return wantarray ? ($sql, @bind) : $sql;
507 my ($self, $expr, $default_scalar_to) = @_;
508 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
509 $self->_expand_expr($expr, undef);
513 my ($self, $aqt) = @_;
514 my ($k, $v, @rest) = %$aqt;
516 if (my $meth = $self->{render}{$k}) {
517 return $self->$meth($v);
519 die "notreached: $k";
523 my ($self, $expr, $logic, $default_scalar_to) = @_;
524 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
525 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
526 return undef unless defined($expr);
527 if (ref($expr) eq 'HASH') {
528 if (keys %$expr > 1) {
532 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
536 return undef unless keys %$expr;
537 return $self->_expand_expr_hashpair(%$expr, $logic);
539 if (ref($expr) eq 'ARRAY') {
540 my $logic = lc($logic || $self->{logic});
541 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
544 (ref($_) eq 'ARRAY' and @$_)
545 or (ref($_) eq 'HASH' and %$_)
551 while (my ($el) = splice @expr, 0, 1) {
552 puke "Supplying an empty left hand side argument is not supported in array-pairs"
553 unless defined($el) and length($el);
554 my $elref = ref($el);
556 local $Expand_Depth = 0;
557 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
558 } elsif ($elref eq 'ARRAY') {
559 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
560 } elsif (my $l = is_literal_value($el)) {
561 push @res, { -literal => $l };
562 } elsif ($elref eq 'HASH') {
563 local $Expand_Depth = 0;
564 push @res, grep defined, $self->_expand_expr($el) if %$el;
569 return { -op => [ $logic, @res ] };
571 if (my $literal = is_literal_value($expr)) {
572 return +{ -literal => $literal };
574 if (!ref($expr) or Scalar::Util::blessed($expr)) {
575 if (my $d = $Default_Scalar_To) {
576 return $self->_expand_expr({ $d => $expr });
578 if (my $m = our $Cur_Col_Meta) {
579 return +{ -bind => [ $m, $expr ] };
581 return +{ -bind => [ undef, $expr ] };
586 sub _expand_expr_hashpair {
587 my ($self, $k, $v, $logic) = @_;
588 unless (defined($k) and length($k)) {
589 if (defined($k) and my $literal = is_literal_value($v)) {
590 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
591 return { -literal => $literal };
593 puke "Supplying an empty left hand side argument is not supported";
596 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
597 if ($k =~ s/ [_\s]? \d+ $//x ) {
598 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
599 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
602 # DBIx::Class requires a nest warning to be emitted once but the private
603 # method it overrode to do so no longer exists
604 if ($self->{is_dbic_sqlmaker}) {
605 unless (our $Nest_Warned) {
607 "-nest in search conditions is deprecated, you most probably wanted:\n"
608 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
613 return $self->_expand_expr($v);
617 return $self->_expand_expr($v);
619 puke "-bool => undef not supported" unless defined($v);
620 return { -ident => $v };
623 return { -op => [ 'not', $self->_expand_expr($v) ] };
625 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
628 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
631 if (my ($logic) = $k =~ /^-(and|or)$/i) {
632 if (ref($v) eq 'HASH') {
633 return $self->_expand_expr($v, $logic);
635 if (ref($v) eq 'ARRAY') {
636 return $self->_expand_expr($v, $logic);
641 $op =~ s/^-// if length($op) > 1;
643 # top level special ops are illegal in general
644 # note that, arguably, if it makes no sense at top level, it also
645 # makes no sense on the other side of an = sign or similar but DBIC
646 # gets disappointingly upset if I disallow it
648 (our $Expand_Depth) == 1
649 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
651 puke "Illegal use of top-level '-$op'"
653 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
654 return { -op => [ $op, $v ] };
657 if ($k eq '-value') {
658 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
660 if (my $custom = $self->{expand_unary}{$k}) {
661 return $self->$custom($v);
663 if ($self->{render}{$k}) {
669 and (keys %$v)[0] =~ /^-/
671 my ($func) = $k =~ /^-(.*)$/;
672 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
673 return +{ -op => [ $func, $self->_expand_expr($v) ] };
675 return +{ -func => [ $func, $self->_expand_expr($v) ] };
677 if (!ref($v) or is_literal_value($v)) {
678 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
685 and exists $v->{-value}
686 and not defined $v->{-value}
689 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
691 if (!ref($v) or Scalar::Util::blessed($v)) {
692 my $d = our $Default_Scalar_To;
697 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
701 if (ref($v) eq 'HASH') {
705 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
709 return undef unless keys %$v;
713 $self->_assert_pass_injection_guard($vk);
714 if ($vk =~ s/ [_\s]? \d+ $//x ) {
715 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
716 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
718 if ($vk =~ /^(?:not[ _])?between$/) {
719 local our $Cur_Col_Meta = $k;
720 my @rhs = map $self->_expand_expr($_),
721 ref($vv) eq 'ARRAY' ? @$vv : $vv;
723 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
725 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
727 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
730 join(' ', split '_', $vk),
735 if ($vk =~ /^(?:not[ _])?in$/) {
736 if (my $literal = is_literal_value($vv)) {
737 my ($sql, @bind) = @$literal;
738 my $opened_sql = $self->_open_outer_paren($sql);
740 $vk, { -ident => $k },
741 [ { -literal => [ $opened_sql, @bind ] } ]
745 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
746 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
747 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
748 . 'will emit the logically correct SQL instead of raising this exception)'
750 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
752 my @rhs = map $self->_expand_expr($_),
753 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
754 map { defined($_) ? $_: puke($undef_err) }
755 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
756 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
759 join(' ', split '_', $vk),
764 if ($vk eq 'ident') {
765 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
766 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
774 if ($vk eq 'value') {
775 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
779 { -bind => [ $k, $vv ] }
782 if ($vk =~ /^is(?:[ _]not)?$/) {
783 puke "$vk can only take undef as argument"
787 and exists($vv->{-value})
788 and !defined($vv->{-value})
791 return +{ -op => [ $vk.' null', { -ident => $k } ] };
793 if ($vk =~ /^(and|or)$/) {
794 if (ref($vv) eq 'HASH') {
797 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
802 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
803 return { -op => [ $vk, { -ident => $k }, $vv ] };
805 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
809 { -op => [ $vk, $vv ] }
812 if (ref($vv) eq 'ARRAY') {
813 my ($logic, @values) = (
814 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
819 $vk =~ $self->{inequality_op}
820 or join(' ', split '_', $vk) =~ $self->{not_like_op}
822 if (lc($logic) eq '-or' and @values > 1) {
823 my $op = uc join ' ', split '_', $vk;
824 belch "A multi-element arrayref as an argument to the inequality op '$op' "
825 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
826 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
831 # try to DWIM on equality operators
832 my $op = join ' ', split '_', $vk;
834 $op =~ $self->{equality_op} ? $self->sqlfalse
835 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
836 : $op =~ $self->{inequality_op} ? $self->sqltrue
837 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
838 : puke "operator '$op' applied on an empty array (field '$k')";
842 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
850 and exists $vv->{-value}
851 and not defined $vv->{-value}
854 my $op = join ' ', split '_', $vk;
856 $op =~ /^not$/i ? 'is not' # legacy
857 : $op =~ $self->{equality_op} ? 'is'
858 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
859 : $op =~ $self->{inequality_op} ? 'is not'
860 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
861 : puke "unexpected operator '$op' with undef operand";
862 return +{ -op => [ $is.' null', { -ident => $k } ] };
864 local our $Cur_Col_Meta = $k;
868 $self->_expand_expr($vv)
871 if (ref($v) eq 'ARRAY') {
872 return $self->sqlfalse unless @$v;
873 $self->_debug("ARRAY($k) means distribute over elements");
875 $v->[0] =~ /^-((?:and|or))$/i
876 ? ($v = [ @{$v}[1..$#$v] ], $1)
877 : ($self->{logic} || 'or')
881 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
884 if (my $literal = is_literal_value($v)) {
886 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
889 my ($sql, @bind) = @$literal;
890 if ($self->{bindtype} eq 'columns') {
892 $self->_assert_bindval_matches_bindtype($_);
895 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
901 my ($self, $where, $logic) = @_;
903 # Special case: top level simple string treated as literal
905 my $where_exp = (ref($where)
906 ? $self->_expand_expr($where, $logic)
907 : { -literal => [ $where ] });
909 # dispatch expanded expression
911 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
912 # DBIx::Class used to call _recurse_where in scalar context
913 # something else might too...
915 return ($sql, @bind);
918 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
924 my ($self, $ident) = @_;
926 return $self->_convert($self->_quote($ident));
929 my %unop_postfix = map +($_ => 1),
930 'is null', 'is not null',
938 my ($self, $args) = @_;
939 my ($left, $low, $high) = @$args;
940 my ($rhsql, @rhbind) = do {
942 puke "Single arg to between must be a literal"
943 unless $low->{-literal};
946 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
947 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
948 @{$l}[1..$#$l], @{$h}[1..$#$h])
951 my ($lhsql, @lhbind) = $self->render_aqt($left);
953 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
957 }), 'between', 'not between'),
961 my ($self, $args) = @_;
962 my ($lhs, $rhs) = @$args;
965 my ($sql, @bind) = $self->render_aqt($_);
966 push @in_bind, @bind;
969 my ($lhsql, @lbind) = $self->render_aqt($lhs);
971 $lhsql.' '.$self->_sqlcase($op).' ( '
982 my ($op, @args) = @$v;
983 $op =~ s/^-// if length($op) > 1;
985 if (my $h = $special{$op}) {
986 return $self->$h(\@args);
988 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
989 if ($us and @args > 1) {
990 puke "Special op '${op}' requires first value to be identifier"
991 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
992 local our $Expand_Depth = 1;
993 return $self->${\($us->{handler})}($k, $op, $args[1]);
995 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
996 return $self->${\($us->{handler})}($op, $args[0]);
998 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
999 if (@args == 1 and $op !~ /^(and|or)$/) {
1000 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1001 my $op_sql = $self->_sqlcase($final_op);
1003 $unop_postfix{lc($final_op)}
1004 ? "${expr_sql} ${op_sql}"
1005 : "${op_sql} ${expr_sql}"
1007 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1009 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1010 return '' unless @parts;
1011 my $is_andor = !!($op =~ /^(and|or)$/);
1012 return @{$parts[0]} if $is_andor and @parts == 1;
1013 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1014 ' '.$self->_sqlcase($final_op).' ',
1019 map @{$_}[1..$#$_], @parts
1026 my ($self, $list) = @_;
1027 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
1028 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1032 my ($self, $rest) = @_;
1033 my ($func, @args) = @$rest;
1037 push @arg_sql, shift @x;
1039 } map [ $self->render_aqt($_) ], @args;
1040 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1044 my ($self, $bind) = @_;
1045 return ($self->_convert('?'), $self->_bindtype(@$bind));
1048 sub _render_literal {
1049 my ($self, $literal) = @_;
1050 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1054 # Some databases (SQLite) treat col IN (1, 2) different from
1055 # col IN ( (1, 2) ). Use this to strip all outer parens while
1056 # adding them back in the corresponding method
1057 sub _open_outer_paren {
1058 my ($self, $sql) = @_;
1060 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1062 # there are closing parens inside, need the heavy duty machinery
1063 # to reevaluate the extraction starting from $sql (full reevaluation)
1064 if ($inner =~ /\)/) {
1065 require Text::Balanced;
1067 my (undef, $remainder) = do {
1068 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1070 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1073 # the entire expression needs to be a balanced bracketed thing
1074 # (after an extract no remainder sans trailing space)
1075 last if defined $remainder and $remainder =~ /\S/;
1085 #======================================================================
1087 #======================================================================
1089 sub _expand_order_by {
1090 my ($self, $arg) = @_;
1092 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1094 my $expander = sub {
1095 my ($self, $dir, $expr) = @_;
1096 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1097 foreach my $arg (@to_expand) {
1101 and grep /^-(asc|desc)$/, keys %$arg
1103 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1106 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1107 map $self->expand_expr($_, -ident),
1108 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1109 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1112 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1113 sub { shift->$expander(asc => @_) },
1114 sub { shift->$expander(desc => @_) },
1117 return $self->$expander(undef, $arg);
1121 my ($self, $arg) = @_;
1123 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1125 my ($sql, @bind) = $self->render_aqt($expanded);
1127 return '' unless length($sql);
1129 my $final_sql = $self->_sqlcase(' order by ').$sql;
1131 return wantarray ? ($final_sql, @bind) : $final_sql;
1134 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1136 sub _order_by_chunks {
1137 my ($self, $arg) = @_;
1139 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1141 return $self->_chunkify_order_by($expanded);
1144 sub _chunkify_order_by {
1145 my ($self, $expanded) = @_;
1147 return grep length, $self->render_aqt($expanded)
1148 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1151 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1152 return map $self->_chunkify_order_by($_), @$l;
1154 return [ $self->render_aqt($_) ];
1158 #======================================================================
1159 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1160 #======================================================================
1166 $self->_expand_maybe_list_expr($from, undef, -ident)
1171 #======================================================================
1173 #======================================================================
1175 sub _expand_maybe_list_expr {
1176 my ($self, $expr, $logic, $default) = @_;
1178 if (ref($expr) eq 'ARRAY') {
1180 map $self->_expand_expr($_, $logic, $default), @$expr
1187 return $self->_expand_expr($e, $logic, $default);
1190 # highly optimized, as it's called way too often
1192 # my ($self, $label) = @_;
1194 return '' unless defined $_[1];
1195 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1196 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1198 unless ($_[0]->{quote_char}) {
1199 if (ref($_[1]) eq 'ARRAY') {
1200 return join($_[0]->{name_sep}||'.', @{$_[1]});
1202 $_[0]->_assert_pass_injection_guard($_[1]);
1207 my $qref = ref $_[0]->{quote_char};
1209 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1210 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1211 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1213 my $esc = $_[0]->{escape_char} || $r;
1215 # parts containing * are naturally unquoted
1217 $_[0]->{name_sep}||'',
1221 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1223 (ref($_[1]) eq 'ARRAY'
1227 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1235 # Conversion, if applicable
1237 #my ($self, $arg) = @_;
1238 if ($_[0]->{convert_where}) {
1239 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1246 #my ($self, $col, @vals) = @_;
1247 # called often - tighten code
1248 return $_[0]->{bindtype} eq 'columns'
1249 ? map {[$_[1], $_]} @_[2 .. $#_]
1254 # Dies if any element of @bind is not in [colname => value] format
1255 # if bindtype is 'columns'.
1256 sub _assert_bindval_matches_bindtype {
1257 # my ($self, @bind) = @_;
1259 if ($self->{bindtype} eq 'columns') {
1261 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1262 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1268 sub _join_sql_clauses {
1269 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1271 if (@$clauses_aref > 1) {
1272 my $join = " " . $self->_sqlcase($logic) . " ";
1273 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1274 return ($sql, @$bind_aref);
1276 elsif (@$clauses_aref) {
1277 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1280 return (); # if no SQL, ignore @$bind_aref
1285 # Fix SQL case, if so requested
1287 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1288 # don't touch the argument ... crooked logic, but let's not change it!
1289 return $_[0]->{case} ? $_[1] : uc($_[1]);
1293 #======================================================================
1294 # DISPATCHING FROM REFKIND
1295 #======================================================================
1298 my ($self, $data) = @_;
1300 return 'UNDEF' unless defined $data;
1302 # blessed objects are treated like scalars
1303 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1305 return 'SCALAR' unless $ref;
1308 while ($ref eq 'REF') {
1310 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1314 return ($ref||'SCALAR') . ('REF' x $n_steps);
1318 my ($self, $data) = @_;
1319 my @try = ($self->_refkind($data));
1320 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1321 push @try, 'FALLBACK';
1325 sub _METHOD_FOR_refkind {
1326 my ($self, $meth_prefix, $data) = @_;
1329 for (@{$self->_try_refkind($data)}) {
1330 $method = $self->can($meth_prefix."_".$_)
1334 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1338 sub _SWITCH_refkind {
1339 my ($self, $data, $dispatch_table) = @_;
1342 for (@{$self->_try_refkind($data)}) {
1343 $coderef = $dispatch_table->{$_}
1347 puke "no dispatch entry for ".$self->_refkind($data)
1356 #======================================================================
1357 # VALUES, GENERATE, AUTOLOAD
1358 #======================================================================
1360 # LDNOTE: original code from nwiger, didn't touch code in that section
1361 # I feel the AUTOLOAD stuff should not be the default, it should
1362 # only be activated on explicit demand by user.
1366 my $data = shift || return;
1367 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1368 unless ref $data eq 'HASH';
1371 foreach my $k (sort keys %$data) {
1372 my $v = $data->{$k};
1373 $self->_SWITCH_refkind($v, {
1375 if ($self->{array_datatypes}) { # array datatype
1376 push @all_bind, $self->_bindtype($k, $v);
1378 else { # literal SQL with bind
1379 my ($sql, @bind) = @$v;
1380 $self->_assert_bindval_matches_bindtype(@bind);
1381 push @all_bind, @bind;
1384 ARRAYREFREF => sub { # literal SQL with bind
1385 my ($sql, @bind) = @${$v};
1386 $self->_assert_bindval_matches_bindtype(@bind);
1387 push @all_bind, @bind;
1389 SCALARREF => sub { # literal SQL without bind
1391 SCALAR_or_UNDEF => sub {
1392 push @all_bind, $self->_bindtype($k, $v);
1403 my(@sql, @sqlq, @sqlv);
1407 if ($ref eq 'HASH') {
1408 for my $k (sort keys %$_) {
1411 my $label = $self->_quote($k);
1412 if ($r eq 'ARRAY') {
1413 # literal SQL with bind
1414 my ($sql, @bind) = @$v;
1415 $self->_assert_bindval_matches_bindtype(@bind);
1416 push @sqlq, "$label = $sql";
1418 } elsif ($r eq 'SCALAR') {
1419 # literal SQL without bind
1420 push @sqlq, "$label = $$v";
1422 push @sqlq, "$label = ?";
1423 push @sqlv, $self->_bindtype($k, $v);
1426 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1427 } elsif ($ref eq 'ARRAY') {
1428 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1431 if ($r eq 'ARRAY') { # literal SQL with bind
1432 my ($sql, @bind) = @$v;
1433 $self->_assert_bindval_matches_bindtype(@bind);
1436 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1437 # embedded literal SQL
1444 push @sql, '(' . join(', ', @sqlq) . ')';
1445 } elsif ($ref eq 'SCALAR') {
1449 # strings get case twiddled
1450 push @sql, $self->_sqlcase($_);
1454 my $sql = join ' ', @sql;
1456 # this is pretty tricky
1457 # if ask for an array, return ($stmt, @bind)
1458 # otherwise, s/?/shift @sqlv/ to put it inline
1460 return ($sql, @sqlv);
1462 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1463 ref $d ? $d->[1] : $d/e;
1472 # This allows us to check for a local, then _form, attr
1474 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1475 return $self->generate($name, @_);
1486 SQL::Abstract - Generate SQL from Perl data structures
1492 my $sql = SQL::Abstract->new;
1494 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1496 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1498 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1500 my($stmt, @bind) = $sql->delete($table, \%where);
1502 # Then, use these in your DBI statements
1503 my $sth = $dbh->prepare($stmt);
1504 $sth->execute(@bind);
1506 # Just generate the WHERE clause
1507 my($stmt, @bind) = $sql->where(\%where, $order);
1509 # Return values in the same order, for hashed queries
1510 # See PERFORMANCE section for more details
1511 my @bind = $sql->values(\%fieldvals);
1515 This module was inspired by the excellent L<DBIx::Abstract>.
1516 However, in using that module I found that what I really wanted
1517 to do was generate SQL, but still retain complete control over my
1518 statement handles and use the DBI interface. So, I set out to
1519 create an abstract SQL generation module.
1521 While based on the concepts used by L<DBIx::Abstract>, there are
1522 several important differences, especially when it comes to WHERE
1523 clauses. I have modified the concepts used to make the SQL easier
1524 to generate from Perl data structures and, IMO, more intuitive.
1525 The underlying idea is for this module to do what you mean, based
1526 on the data structures you provide it. The big advantage is that
1527 you don't have to modify your code every time your data changes,
1528 as this module figures it out.
1530 To begin with, an SQL INSERT is as easy as just specifying a hash
1531 of C<key=value> pairs:
1534 name => 'Jimbo Bobson',
1535 phone => '123-456-7890',
1536 address => '42 Sister Lane',
1537 city => 'St. Louis',
1538 state => 'Louisiana',
1541 The SQL can then be generated with this:
1543 my($stmt, @bind) = $sql->insert('people', \%data);
1545 Which would give you something like this:
1547 $stmt = "INSERT INTO people
1548 (address, city, name, phone, state)
1549 VALUES (?, ?, ?, ?, ?)";
1550 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1551 '123-456-7890', 'Louisiana');
1553 These are then used directly in your DBI code:
1555 my $sth = $dbh->prepare($stmt);
1556 $sth->execute(@bind);
1558 =head2 Inserting and Updating Arrays
1560 If your database has array types (like for example Postgres),
1561 activate the special option C<< array_datatypes => 1 >>
1562 when creating the C<SQL::Abstract> object.
1563 Then you may use an arrayref to insert and update database array types:
1565 my $sql = SQL::Abstract->new(array_datatypes => 1);
1567 planets => [qw/Mercury Venus Earth Mars/]
1570 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1574 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1576 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1579 =head2 Inserting and Updating SQL
1581 In order to apply SQL functions to elements of your C<%data> you may
1582 specify a reference to an arrayref for the given hash value. For example,
1583 if you need to execute the Oracle C<to_date> function on a value, you can
1584 say something like this:
1588 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1591 The first value in the array is the actual SQL. Any other values are
1592 optional and would be included in the bind values array. This gives
1595 my($stmt, @bind) = $sql->insert('people', \%data);
1597 $stmt = "INSERT INTO people (name, date_entered)
1598 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1599 @bind = ('Bill', '03/02/2003');
1601 An UPDATE is just as easy, all you change is the name of the function:
1603 my($stmt, @bind) = $sql->update('people', \%data);
1605 Notice that your C<%data> isn't touched; the module will generate
1606 the appropriately quirky SQL for you automatically. Usually you'll
1607 want to specify a WHERE clause for your UPDATE, though, which is
1608 where handling C<%where> hashes comes in handy...
1610 =head2 Complex where statements
1612 This module can generate pretty complicated WHERE statements
1613 easily. For example, simple C<key=value> pairs are taken to mean
1614 equality, and if you want to see if a field is within a set
1615 of values, you can use an arrayref. Let's say we wanted to
1616 SELECT some data based on this criteria:
1619 requestor => 'inna',
1620 worker => ['nwiger', 'rcwe', 'sfz'],
1621 status => { '!=', 'completed' }
1624 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1626 The above would give you something like this:
1628 $stmt = "SELECT * FROM tickets WHERE
1629 ( requestor = ? ) AND ( status != ? )
1630 AND ( worker = ? OR worker = ? OR worker = ? )";
1631 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1633 Which you could then use in DBI code like so:
1635 my $sth = $dbh->prepare($stmt);
1636 $sth->execute(@bind);
1642 The methods are simple. There's one for every major SQL operation,
1643 and a constructor you use first. The arguments are specified in a
1644 similar order for each method (table, then fields, then a where
1645 clause) to try and simplify things.
1647 =head2 new(option => 'value')
1649 The C<new()> function takes a list of options and values, and returns
1650 a new B<SQL::Abstract> object which can then be used to generate SQL
1651 through the methods below. The options accepted are:
1657 If set to 'lower', then SQL will be generated in all lowercase. By
1658 default SQL is generated in "textbook" case meaning something like:
1660 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1662 Any setting other than 'lower' is ignored.
1666 This determines what the default comparison operator is. By default
1667 it is C<=>, meaning that a hash like this:
1669 %where = (name => 'nwiger', email => 'nate@wiger.org');
1671 Will generate SQL like this:
1673 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1675 However, you may want loose comparisons by default, so if you set
1676 C<cmp> to C<like> you would get SQL such as:
1678 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1680 You can also override the comparison on an individual basis - see
1681 the huge section on L</"WHERE CLAUSES"> at the bottom.
1683 =item sqltrue, sqlfalse
1685 Expressions for inserting boolean values within SQL statements.
1686 By default these are C<1=1> and C<1=0>. They are used
1687 by the special operators C<-in> and C<-not_in> for generating
1688 correct SQL even when the argument is an empty array (see below).
1692 This determines the default logical operator for multiple WHERE
1693 statements in arrays or hashes. If absent, the default logic is "or"
1694 for arrays, and "and" for hashes. This means that a WHERE
1698 event_date => {'>=', '2/13/99'},
1699 event_date => {'<=', '4/24/03'},
1702 will generate SQL like this:
1704 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1706 This is probably not what you want given this query, though (look
1707 at the dates). To change the "OR" to an "AND", simply specify:
1709 my $sql = SQL::Abstract->new(logic => 'and');
1711 Which will change the above C<WHERE> to:
1713 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1715 The logic can also be changed locally by inserting
1716 a modifier in front of an arrayref:
1718 @where = (-and => [event_date => {'>=', '2/13/99'},
1719 event_date => {'<=', '4/24/03'} ]);
1721 See the L</"WHERE CLAUSES"> section for explanations.
1725 This will automatically convert comparisons using the specified SQL
1726 function for both column and value. This is mostly used with an argument
1727 of C<upper> or C<lower>, so that the SQL will have the effect of
1728 case-insensitive "searches". For example, this:
1730 $sql = SQL::Abstract->new(convert => 'upper');
1731 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1733 Will turn out the following SQL:
1735 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1737 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1738 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1739 not validate this option; it will just pass through what you specify verbatim).
1743 This is a kludge because many databases suck. For example, you can't
1744 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1745 Instead, you have to use C<bind_param()>:
1747 $sth->bind_param(1, 'reg data');
1748 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1750 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1751 which loses track of which field each slot refers to. Fear not.
1753 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1754 Currently, you can specify either C<normal> (default) or C<columns>. If you
1755 specify C<columns>, you will get an array that looks like this:
1757 my $sql = SQL::Abstract->new(bindtype => 'columns');
1758 my($stmt, @bind) = $sql->insert(...);
1761 [ 'column1', 'value1' ],
1762 [ 'column2', 'value2' ],
1763 [ 'column3', 'value3' ],
1766 You can then iterate through this manually, using DBI's C<bind_param()>.
1768 $sth->prepare($stmt);
1771 my($col, $data) = @$_;
1772 if ($col eq 'details' || $col eq 'comments') {
1773 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1774 } elsif ($col eq 'image') {
1775 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1777 $sth->bind_param($i, $data);
1781 $sth->execute; # execute without @bind now
1783 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1784 Basically, the advantage is still that you don't have to care which fields
1785 are or are not included. You could wrap that above C<for> loop in a simple
1786 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1787 get a layer of abstraction over manual SQL specification.
1789 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1790 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1791 will expect the bind values in this format.
1795 This is the character that a table or column name will be quoted
1796 with. By default this is an empty string, but you could set it to
1797 the character C<`>, to generate SQL like this:
1799 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1801 Alternatively, you can supply an array ref of two items, the first being the left
1802 hand quote character, and the second the right hand quote character. For
1803 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1804 that generates SQL like this:
1806 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1808 Quoting is useful if you have tables or columns names that are reserved
1809 words in your database's SQL dialect.
1813 This is the character that will be used to escape L</quote_char>s appearing
1814 in an identifier before it has been quoted.
1816 The parameter default in case of a single L</quote_char> character is the quote
1819 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1820 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1821 of the B<opening (left)> L</quote_char> within the identifier are currently left
1822 untouched. The default for opening-closing-style quotes may change in future
1823 versions, thus you are B<strongly encouraged> to specify the escape character
1828 This is the character that separates a table and column name. It is
1829 necessary to specify this when the C<quote_char> option is selected,
1830 so that tables and column names can be individually quoted like this:
1832 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1834 =item injection_guard
1836 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1837 column name specified in a query structure. This is a safety mechanism to avoid
1838 injection attacks when mishandling user input e.g.:
1840 my %condition_as_column_value_pairs = get_values_from_user();
1841 $sqla->select( ... , \%condition_as_column_value_pairs );
1843 If the expression matches an exception is thrown. Note that literal SQL
1844 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1846 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1848 =item array_datatypes
1850 When this option is true, arrayrefs in INSERT or UPDATE are
1851 interpreted as array datatypes and are passed directly
1853 When this option is false, arrayrefs are interpreted
1854 as literal SQL, just like refs to arrayrefs
1855 (but this behavior is for backwards compatibility; when writing
1856 new queries, use the "reference to arrayref" syntax
1862 Takes a reference to a list of "special operators"
1863 to extend the syntax understood by L<SQL::Abstract>.
1864 See section L</"SPECIAL OPERATORS"> for details.
1868 Takes a reference to a list of "unary operators"
1869 to extend the syntax understood by L<SQL::Abstract>.
1870 See section L</"UNARY OPERATORS"> for details.
1876 =head2 insert($table, \@values || \%fieldvals, \%options)
1878 This is the simplest function. You simply give it a table name
1879 and either an arrayref of values or hashref of field/value pairs.
1880 It returns an SQL INSERT statement and a list of bind values.
1881 See the sections on L</"Inserting and Updating Arrays"> and
1882 L</"Inserting and Updating SQL"> for information on how to insert
1883 with those data types.
1885 The optional C<\%options> hash reference may contain additional
1886 options to generate the insert SQL. Currently supported options
1893 Takes either a scalar of raw SQL fields, or an array reference of
1894 field names, and adds on an SQL C<RETURNING> statement at the end.
1895 This allows you to return data generated by the insert statement
1896 (such as row IDs) without performing another C<SELECT> statement.
1897 Note, however, this is not part of the SQL standard and may not
1898 be supported by all database engines.
1902 =head2 update($table, \%fieldvals, \%where, \%options)
1904 This takes a table, hashref of field/value pairs, and an optional
1905 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1907 See the sections on L</"Inserting and Updating Arrays"> and
1908 L</"Inserting and Updating SQL"> for information on how to insert
1909 with those data types.
1911 The optional C<\%options> hash reference may contain additional
1912 options to generate the update SQL. Currently supported options
1919 See the C<returning> option to
1920 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1924 =head2 select($source, $fields, $where, $order)
1926 This returns a SQL SELECT statement and associated list of bind values, as
1927 specified by the arguments:
1933 Specification of the 'FROM' part of the statement.
1934 The argument can be either a plain scalar (interpreted as a table
1935 name, will be quoted), or an arrayref (interpreted as a list
1936 of table names, joined by commas, quoted), or a scalarref
1937 (literal SQL, not quoted).
1941 Specification of the list of fields to retrieve from
1943 The argument can be either an arrayref (interpreted as a list
1944 of field names, will be joined by commas and quoted), or a
1945 plain scalar (literal SQL, not quoted).
1946 Please observe that this API is not as flexible as that of
1947 the first argument C<$source>, for backwards compatibility reasons.
1951 Optional argument to specify the WHERE part of the query.
1952 The argument is most often a hashref, but can also be
1953 an arrayref or plain scalar --
1954 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1958 Optional argument to specify the ORDER BY part of the query.
1959 The argument can be a scalar, a hashref or an arrayref
1960 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1966 =head2 delete($table, \%where, \%options)
1968 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1969 It returns an SQL DELETE statement and list of bind values.
1971 The optional C<\%options> hash reference may contain additional
1972 options to generate the delete SQL. Currently supported options
1979 See the C<returning> option to
1980 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1984 =head2 where(\%where, $order)
1986 This is used to generate just the WHERE clause. For example,
1987 if you have an arbitrary data structure and know what the
1988 rest of your SQL is going to look like, but want an easy way
1989 to produce a WHERE clause, use this. It returns an SQL WHERE
1990 clause and list of bind values.
1993 =head2 values(\%data)
1995 This just returns the values from the hash C<%data>, in the same
1996 order that would be returned from any of the other above queries.
1997 Using this allows you to markedly speed up your queries if you
1998 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2000 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2002 Warning: This is an experimental method and subject to change.
2004 This returns arbitrarily generated SQL. It's a really basic shortcut.
2005 It will return two different things, depending on return context:
2007 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2008 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2010 These would return the following:
2012 # First calling form
2013 $stmt = "CREATE TABLE test (?, ?)";
2014 @bind = (field1, field2);
2016 # Second calling form
2017 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2019 Depending on what you're trying to do, it's up to you to choose the correct
2020 format. In this example, the second form is what you would want.
2024 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2028 ALTER SESSION SET nls_date_format = 'MM/YY'
2030 You get the idea. Strings get their case twiddled, but everything
2031 else remains verbatim.
2033 =head1 EXPORTABLE FUNCTIONS
2035 =head2 is_plain_value
2037 Determines if the supplied argument is a plain value as understood by this
2042 =item * The value is C<undef>
2044 =item * The value is a non-reference
2046 =item * The value is an object with stringification overloading
2048 =item * The value is of the form C<< { -value => $anything } >>
2052 On failure returns C<undef>, on success returns a B<scalar> reference
2053 to the original supplied argument.
2059 The stringification overloading detection is rather advanced: it takes
2060 into consideration not only the presence of a C<""> overload, but if that
2061 fails also checks for enabled
2062 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2063 on either C<0+> or C<bool>.
2065 Unfortunately testing in the field indicates that this
2066 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2067 but only when very large numbers of stringifying objects are involved.
2068 At the time of writing ( Sep 2014 ) there is no clear explanation of
2069 the direct cause, nor is there a manageably small test case that reliably
2070 reproduces the problem.
2072 If you encounter any of the following exceptions in B<random places within
2073 your application stack> - this module may be to blame:
2075 Operation "ne": no method found,
2076 left argument in overloaded package <something>,
2077 right argument in overloaded package <something>
2081 Stub found while resolving method "???" overloading """" in package <something>
2083 If you fall victim to the above - please attempt to reduce the problem
2084 to something that could be sent to the L<SQL::Abstract developers
2085 |DBIx::Class/GETTING HELP/SUPPORT>
2086 (either publicly or privately). As a workaround in the meantime you can
2087 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2088 value, which will most likely eliminate your problem (at the expense of
2089 not being able to properly detect exotic forms of stringification).
2091 This notice and environment variable will be removed in a future version,
2092 as soon as the underlying problem is found and a reliable workaround is
2097 =head2 is_literal_value
2099 Determines if the supplied argument is a literal value as understood by this
2104 =item * C<\$sql_string>
2106 =item * C<\[ $sql_string, @bind_values ]>
2110 On failure returns C<undef>, on success returns an B<array> reference
2111 containing the unpacked version of the supplied literal SQL and bind values.
2113 =head1 WHERE CLAUSES
2117 This module uses a variation on the idea from L<DBIx::Abstract>. It
2118 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2119 module is that things in arrays are OR'ed, and things in hashes
2122 The easiest way to explain is to show lots of examples. After
2123 each C<%where> hash shown, it is assumed you used:
2125 my($stmt, @bind) = $sql->where(\%where);
2127 However, note that the C<%where> hash can be used directly in any
2128 of the other functions as well, as described above.
2130 =head2 Key-value pairs
2132 So, let's get started. To begin, a simple hash:
2136 status => 'completed'
2139 Is converted to SQL C<key = val> statements:
2141 $stmt = "WHERE user = ? AND status = ?";
2142 @bind = ('nwiger', 'completed');
2144 One common thing I end up doing is having a list of values that
2145 a field can be in. To do this, simply specify a list inside of
2150 status => ['assigned', 'in-progress', 'pending'];
2153 This simple code will create the following:
2155 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2156 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2158 A field associated to an empty arrayref will be considered a
2159 logical false and will generate 0=1.
2161 =head2 Tests for NULL values
2163 If the value part is C<undef> then this is converted to SQL <IS NULL>
2172 $stmt = "WHERE user = ? AND status IS NULL";
2175 To test if a column IS NOT NULL:
2179 status => { '!=', undef },
2182 =head2 Specific comparison operators
2184 If you want to specify a different type of operator for your comparison,
2185 you can use a hashref for a given column:
2189 status => { '!=', 'completed' }
2192 Which would generate:
2194 $stmt = "WHERE user = ? AND status != ?";
2195 @bind = ('nwiger', 'completed');
2197 To test against multiple values, just enclose the values in an arrayref:
2199 status => { '=', ['assigned', 'in-progress', 'pending'] };
2201 Which would give you:
2203 "WHERE status = ? OR status = ? OR status = ?"
2206 The hashref can also contain multiple pairs, in which case it is expanded
2207 into an C<AND> of its elements:
2211 status => { '!=', 'completed', -not_like => 'pending%' }
2214 # Or more dynamically, like from a form
2215 $where{user} = 'nwiger';
2216 $where{status}{'!='} = 'completed';
2217 $where{status}{'-not_like'} = 'pending%';
2219 # Both generate this
2220 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2221 @bind = ('nwiger', 'completed', 'pending%');
2224 To get an OR instead, you can combine it with the arrayref idea:
2228 priority => [ { '=', 2 }, { '>', 5 } ]
2231 Which would generate:
2233 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2234 @bind = ('2', '5', 'nwiger');
2236 If you want to include literal SQL (with or without bind values), just use a
2237 scalar reference or reference to an arrayref as the value:
2240 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2241 date_expires => { '<' => \"now()" }
2244 Which would generate:
2246 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2247 @bind = ('11/26/2008');
2250 =head2 Logic and nesting operators
2252 In the example above,
2253 there is a subtle trap if you want to say something like
2254 this (notice the C<AND>):
2256 WHERE priority != ? AND priority != ?
2258 Because, in Perl you I<can't> do this:
2260 priority => { '!=' => 2, '!=' => 1 }
2262 As the second C<!=> key will obliterate the first. The solution
2263 is to use the special C<-modifier> form inside an arrayref:
2265 priority => [ -and => {'!=', 2},
2269 Normally, these would be joined by C<OR>, but the modifier tells it
2270 to use C<AND> instead. (Hint: You can use this in conjunction with the
2271 C<logic> option to C<new()> in order to change the way your queries
2272 work by default.) B<Important:> Note that the C<-modifier> goes
2273 B<INSIDE> the arrayref, as an extra first element. This will
2274 B<NOT> do what you think it might:
2276 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2278 Here is a quick list of equivalencies, since there is some overlap:
2281 status => {'!=', 'completed', 'not like', 'pending%' }
2282 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2285 status => {'=', ['assigned', 'in-progress']}
2286 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2287 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2291 =head2 Special operators: IN, BETWEEN, etc.
2293 You can also use the hashref format to compare a list of fields using the
2294 C<IN> comparison operator, by specifying the list as an arrayref:
2297 status => 'completed',
2298 reportid => { -in => [567, 2335, 2] }
2301 Which would generate:
2303 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2304 @bind = ('completed', '567', '2335', '2');
2306 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2309 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2310 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2311 'sqltrue' (by default: C<1=1>).
2313 In addition to the array you can supply a chunk of literal sql or
2314 literal sql with bind:
2317 customer => { -in => \[
2318 'SELECT cust_id FROM cust WHERE balance > ?',
2321 status => { -in => \'SELECT status_codes FROM states' },
2327 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2328 AND status IN ( SELECT status_codes FROM states )
2332 Finally, if the argument to C<-in> is not a reference, it will be
2333 treated as a single-element array.
2335 Another pair of operators is C<-between> and C<-not_between>,
2336 used with an arrayref of two values:
2340 completion_date => {
2341 -not_between => ['2002-10-01', '2003-02-06']
2347 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2349 Just like with C<-in> all plausible combinations of literal SQL
2353 start0 => { -between => [ 1, 2 ] },
2354 start1 => { -between => \["? AND ?", 1, 2] },
2355 start2 => { -between => \"lower(x) AND upper(y)" },
2356 start3 => { -between => [
2358 \["upper(?)", 'stuff' ],
2365 ( start0 BETWEEN ? AND ? )
2366 AND ( start1 BETWEEN ? AND ? )
2367 AND ( start2 BETWEEN lower(x) AND upper(y) )
2368 AND ( start3 BETWEEN lower(x) AND upper(?) )
2370 @bind = (1, 2, 1, 2, 'stuff');
2373 These are the two builtin "special operators"; but the
2374 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2376 =head2 Unary operators: bool
2378 If you wish to test against boolean columns or functions within your
2379 database you can use the C<-bool> and C<-not_bool> operators. For
2380 example to test the column C<is_user> being true and the column
2381 C<is_enabled> being false you would use:-
2385 -not_bool => 'is_enabled',
2390 WHERE is_user AND NOT is_enabled
2392 If a more complex combination is required, testing more conditions,
2393 then you should use the and/or operators:-
2398 -not_bool => { two=> { -rlike => 'bar' } },
2399 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2410 (NOT ( three = ? OR three > ? ))
2413 =head2 Nested conditions, -and/-or prefixes
2415 So far, we've seen how multiple conditions are joined with a top-level
2416 C<AND>. We can change this by putting the different conditions we want in
2417 hashes and then putting those hashes in an array. For example:
2422 status => { -like => ['pending%', 'dispatched'] },
2426 status => 'unassigned',
2430 This data structure would create the following:
2432 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2433 OR ( user = ? AND status = ? ) )";
2434 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2437 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2438 to change the logic inside:
2444 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2445 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2452 $stmt = "WHERE ( user = ?
2453 AND ( ( workhrs > ? AND geo = ? )
2454 OR ( workhrs < ? OR geo = ? ) ) )";
2455 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2457 =head3 Algebraic inconsistency, for historical reasons
2459 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2460 operator goes C<outside> of the nested structure; whereas when connecting
2461 several constraints on one column, the C<-and> operator goes
2462 C<inside> the arrayref. Here is an example combining both features:
2465 -and => [a => 1, b => 2],
2466 -or => [c => 3, d => 4],
2467 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2472 WHERE ( ( ( a = ? AND b = ? )
2473 OR ( c = ? OR d = ? )
2474 OR ( e LIKE ? AND e LIKE ? ) ) )
2476 This difference in syntax is unfortunate but must be preserved for
2477 historical reasons. So be careful: the two examples below would
2478 seem algebraically equivalent, but they are not
2481 { -like => 'foo%' },
2482 { -like => '%bar' },
2484 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2487 { col => { -like => 'foo%' } },
2488 { col => { -like => '%bar' } },
2490 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2493 =head2 Literal SQL and value type operators
2495 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2496 side" is a column name and the "right side" is a value (normally rendered as
2497 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2498 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2499 alter this behavior. There are several ways of doing so.
2503 This is a virtual operator that signals the string to its right side is an
2504 identifier (a column name) and not a value. For example to compare two
2505 columns you would write:
2508 priority => { '<', 2 },
2509 requestor => { -ident => 'submitter' },
2514 $stmt = "WHERE priority < ? AND requestor = submitter";
2517 If you are maintaining legacy code you may see a different construct as
2518 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2523 This is a virtual operator that signals that the construct to its right side
2524 is a value to be passed to DBI. This is for example necessary when you want
2525 to write a where clause against an array (for RDBMS that support such
2526 datatypes). For example:
2529 array => { -value => [1, 2, 3] }
2534 $stmt = 'WHERE array = ?';
2535 @bind = ([1, 2, 3]);
2537 Note that if you were to simply say:
2543 the result would probably not be what you wanted:
2545 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2550 Finally, sometimes only literal SQL will do. To include a random snippet
2551 of SQL verbatim, you specify it as a scalar reference. Consider this only
2552 as a last resort. Usually there is a better way. For example:
2555 priority => { '<', 2 },
2556 requestor => { -in => \'(SELECT name FROM hitmen)' },
2561 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2564 Note that in this example, you only get one bind parameter back, since
2565 the verbatim SQL is passed as part of the statement.
2569 Never use untrusted input as a literal SQL argument - this is a massive
2570 security risk (there is no way to check literal snippets for SQL
2571 injections and other nastyness). If you need to deal with untrusted input
2572 use literal SQL with placeholders as described next.
2574 =head3 Literal SQL with placeholders and bind values (subqueries)
2576 If the literal SQL to be inserted has placeholders and bind values,
2577 use a reference to an arrayref (yes this is a double reference --
2578 not so common, but perfectly legal Perl). For example, to find a date
2579 in Postgres you can use something like this:
2582 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2587 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2590 Note that you must pass the bind values in the same format as they are returned
2591 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2592 to C<columns>, you must provide the bind values in the
2593 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2594 scalar value; most commonly the column name, but you can use any scalar value
2595 (including references and blessed references), L<SQL::Abstract> will simply
2596 pass it through intact. So if C<bindtype> is set to C<columns> the above
2597 example will look like:
2600 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2603 Literal SQL is especially useful for nesting parenthesized clauses in the
2604 main SQL query. Here is a first example:
2606 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2610 bar => \["IN ($sub_stmt)" => @sub_bind],
2615 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2616 WHERE c2 < ? AND c3 LIKE ?))";
2617 @bind = (1234, 100, "foo%");
2619 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2620 are expressed in the same way. Of course the C<$sub_stmt> and
2621 its associated bind values can be generated through a former call
2624 my ($sub_stmt, @sub_bind)
2625 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2626 c3 => {-like => "foo%"}});
2629 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2632 In the examples above, the subquery was used as an operator on a column;
2633 but the same principle also applies for a clause within the main C<%where>
2634 hash, like an EXISTS subquery:
2636 my ($sub_stmt, @sub_bind)
2637 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2638 my %where = ( -and => [
2640 \["EXISTS ($sub_stmt)" => @sub_bind],
2645 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2646 WHERE c1 = ? AND c2 > t0.c0))";
2650 Observe that the condition on C<c2> in the subquery refers to
2651 column C<t0.c0> of the main query: this is I<not> a bind
2652 value, so we have to express it through a scalar ref.
2653 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2654 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2655 what we wanted here.
2657 Finally, here is an example where a subquery is used
2658 for expressing unary negation:
2660 my ($sub_stmt, @sub_bind)
2661 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2662 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2664 lname => {like => '%son%'},
2665 \["NOT ($sub_stmt)" => @sub_bind],
2670 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2671 @bind = ('%son%', 10, 20)
2673 =head3 Deprecated usage of Literal SQL
2675 Below are some examples of archaic use of literal SQL. It is shown only as
2676 reference for those who deal with legacy code. Each example has a much
2677 better, cleaner and safer alternative that users should opt for in new code.
2683 my %where = ( requestor => \'IS NOT NULL' )
2685 $stmt = "WHERE requestor IS NOT NULL"
2687 This used to be the way of generating NULL comparisons, before the handling
2688 of C<undef> got formalized. For new code please use the superior syntax as
2689 described in L</Tests for NULL values>.
2693 my %where = ( requestor => \'= submitter' )
2695 $stmt = "WHERE requestor = submitter"
2697 This used to be the only way to compare columns. Use the superior L</-ident>
2698 method for all new code. For example an identifier declared in such a way
2699 will be properly quoted if L</quote_char> is properly set, while the legacy
2700 form will remain as supplied.
2704 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2706 $stmt = "WHERE completed > ? AND is_ready"
2707 @bind = ('2012-12-21')
2709 Using an empty string literal used to be the only way to express a boolean.
2710 For all new code please use the much more readable
2711 L<-bool|/Unary operators: bool> operator.
2717 These pages could go on for a while, since the nesting of the data
2718 structures this module can handle are pretty much unlimited (the
2719 module implements the C<WHERE> expansion as a recursive function
2720 internally). Your best bet is to "play around" with the module a
2721 little to see how the data structures behave, and choose the best
2722 format for your data based on that.
2724 And of course, all the values above will probably be replaced with
2725 variables gotten from forms or the command line. After all, if you
2726 knew everything ahead of time, you wouldn't have to worry about
2727 dynamically-generating SQL and could just hardwire it into your
2730 =head1 ORDER BY CLAUSES
2732 Some functions take an order by clause. This can either be a scalar (just a
2733 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2734 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2737 Given | Will Generate
2738 ---------------------------------------------------------------
2740 'colA' | ORDER BY colA
2742 [qw/colA colB/] | ORDER BY colA, colB
2744 {-asc => 'colA'} | ORDER BY colA ASC
2746 {-desc => 'colB'} | ORDER BY colB DESC
2748 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2750 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2752 \'colA DESC' | ORDER BY colA DESC
2754 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2755 | /* ...with $x bound to ? */
2758 { -asc => 'colA' }, | colA ASC,
2759 { -desc => [qw/colB/] }, | colB DESC,
2760 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2761 \'colE DESC', | colE DESC,
2762 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2763 ] | /* ...with $x bound to ? */
2764 ===============================================================
2768 =head1 SPECIAL OPERATORS
2770 my $sqlmaker = SQL::Abstract->new(special_ops => [
2774 my ($self, $field, $op, $arg) = @_;
2780 handler => 'method_name',
2784 A "special operator" is a SQL syntactic clause that can be
2785 applied to a field, instead of a usual binary operator.
2788 WHERE field IN (?, ?, ?)
2789 WHERE field BETWEEN ? AND ?
2790 WHERE MATCH(field) AGAINST (?, ?)
2792 Special operators IN and BETWEEN are fairly standard and therefore
2793 are builtin within C<SQL::Abstract> (as the overridable methods
2794 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2795 like the MATCH .. AGAINST example above which is specific to MySQL,
2796 you can write your own operator handlers - supply a C<special_ops>
2797 argument to the C<new> method. That argument takes an arrayref of
2798 operator definitions; each operator definition is a hashref with two
2805 the regular expression to match the operator
2809 Either a coderef or a plain scalar method name. In both cases
2810 the expected return is C<< ($sql, @bind) >>.
2812 When supplied with a method name, it is simply called on the
2813 L<SQL::Abstract> object as:
2815 $self->$method_name($field, $op, $arg)
2819 $field is the LHS of the operator
2820 $op is the part that matched the handler regex
2823 When supplied with a coderef, it is called as:
2825 $coderef->($self, $field, $op, $arg)
2830 For example, here is an implementation
2831 of the MATCH .. AGAINST syntax for MySQL
2833 my $sqlmaker = SQL::Abstract->new(special_ops => [
2835 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2836 {regex => qr/^match$/i,
2838 my ($self, $field, $op, $arg) = @_;
2839 $arg = [$arg] if not ref $arg;
2840 my $label = $self->_quote($field);
2841 my ($placeholder) = $self->_convert('?');
2842 my $placeholders = join ", ", (($placeholder) x @$arg);
2843 my $sql = $self->_sqlcase('match') . " ($label) "
2844 . $self->_sqlcase('against') . " ($placeholders) ";
2845 my @bind = $self->_bindtype($field, @$arg);
2846 return ($sql, @bind);
2853 =head1 UNARY OPERATORS
2855 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2859 my ($self, $op, $arg) = @_;
2865 handler => 'method_name',
2869 A "unary operator" is a SQL syntactic clause that can be
2870 applied to a field - the operator goes before the field
2872 You can write your own operator handlers - supply a C<unary_ops>
2873 argument to the C<new> method. That argument takes an arrayref of
2874 operator definitions; each operator definition is a hashref with two
2881 the regular expression to match the operator
2885 Either a coderef or a plain scalar method name. In both cases
2886 the expected return is C<< $sql >>.
2888 When supplied with a method name, it is simply called on the
2889 L<SQL::Abstract> object as:
2891 $self->$method_name($op, $arg)
2895 $op is the part that matched the handler regex
2896 $arg is the RHS or argument of the operator
2898 When supplied with a coderef, it is called as:
2900 $coderef->($self, $op, $arg)
2908 Thanks to some benchmarking by Mark Stosberg, it turns out that
2909 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2910 I must admit this wasn't an intentional design issue, but it's a
2911 byproduct of the fact that you get to control your C<DBI> handles
2914 To maximize performance, use a code snippet like the following:
2916 # prepare a statement handle using the first row
2917 # and then reuse it for the rest of the rows
2919 for my $href (@array_of_hashrefs) {
2920 $stmt ||= $sql->insert('table', $href);
2921 $sth ||= $dbh->prepare($stmt);
2922 $sth->execute($sql->values($href));
2925 The reason this works is because the keys in your C<$href> are sorted
2926 internally by B<SQL::Abstract>. Thus, as long as your data retains
2927 the same structure, you only have to generate the SQL the first time
2928 around. On subsequent queries, simply use the C<values> function provided
2929 by this module to return your values in the correct order.
2931 However this depends on the values having the same type - if, for
2932 example, the values of a where clause may either have values
2933 (resulting in sql of the form C<column = ?> with a single bind
2934 value), or alternatively the values might be C<undef> (resulting in
2935 sql of the form C<column IS NULL> with no bind value) then the
2936 caching technique suggested will not work.
2940 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2941 really like this part (I do, at least). Building up a complex query
2942 can be as simple as the following:
2949 use CGI::FormBuilder;
2952 my $form = CGI::FormBuilder->new(...);
2953 my $sql = SQL::Abstract->new;
2955 if ($form->submitted) {
2956 my $field = $form->field;
2957 my $id = delete $field->{id};
2958 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2961 Of course, you would still have to connect using C<DBI> to run the
2962 query, but the point is that if you make your form look like your
2963 table, the actual query script can be extremely simplistic.
2965 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2966 a fast interface to returning and formatting data. I frequently
2967 use these three modules together to write complex database query
2968 apps in under 50 lines.
2970 =head1 HOW TO CONTRIBUTE
2972 Contributions are always welcome, in all usable forms (we especially
2973 welcome documentation improvements). The delivery methods include git-
2974 or unified-diff formatted patches, GitHub pull requests, or plain bug
2975 reports either via RT or the Mailing list. Contributors are generally
2976 granted full access to the official repository after their first several
2977 patches pass successful review.
2979 This project is maintained in a git repository. The code and related tools are
2980 accessible at the following locations:
2984 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2986 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2988 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2990 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2996 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2997 Great care has been taken to preserve the I<published> behavior
2998 documented in previous versions in the 1.* family; however,
2999 some features that were previously undocumented, or behaved
3000 differently from the documentation, had to be changed in order
3001 to clarify the semantics. Hence, client code that was relying
3002 on some dark areas of C<SQL::Abstract> v1.*
3003 B<might behave differently> in v1.50.
3005 The main changes are:
3011 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3015 support for the { operator => \"..." } construct (to embed literal SQL)
3019 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3023 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3027 defensive programming: check arguments
3031 fixed bug with global logic, which was previously implemented
3032 through global variables yielding side-effects. Prior versions would
3033 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3034 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3035 Now this is interpreted
3036 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3041 fixed semantics of _bindtype on array args
3045 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3046 we just avoid shifting arrays within that tree.
3050 dropped the C<_modlogic> function
3054 =head1 ACKNOWLEDGEMENTS
3056 There are a number of individuals that have really helped out with
3057 this module. Unfortunately, most of them submitted bugs via CPAN
3058 so I have no idea who they are! But the people I do know are:
3060 Ash Berlin (order_by hash term support)
3061 Matt Trout (DBIx::Class support)
3062 Mark Stosberg (benchmarking)
3063 Chas Owens (initial "IN" operator support)
3064 Philip Collins (per-field SQL functions)
3065 Eric Kolve (hashref "AND" support)
3066 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3067 Dan Kubb (support for "quote_char" and "name_sep")
3068 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3069 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3070 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3071 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3072 Oliver Charles (support for "RETURNING" after "INSERT")
3078 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3082 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3084 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3086 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3087 While not an official support venue, C<DBIx::Class> makes heavy use of
3088 C<SQL::Abstract>, and as such list members there are very familiar with
3089 how to create queries.
3093 This module is free software; you may copy this under the same
3094 terms as perl itself (either the GNU General Public License or
3095 the Artistic License)