1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class =~ /^DBIx::Class::SQLMaker/) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
170 $opt{unary_ops} ||= [];
172 # rudimentary sanity-check for user supplied bits treated as functions/operators
173 # If a purported function matches this regular expression, an exception is thrown.
174 # Literal SQL is *NOT* subject to this check, only functions (and column names
175 # when quoting is not in effect)
178 # need to guard against ()'s in column names too, but this will break tons of
179 # hacks... ideas anyone?
180 $opt{injection_guard} ||= qr/
186 $opt{node_types} = +{
187 map +("-$_" => '_render_'.$_),
188 qw(op func value bind ident literal)
191 $opt{expand_unary} = {};
193 return bless \%opt, $class;
196 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
197 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
199 sub _assert_pass_injection_guard {
200 if ($_[1] =~ $_[0]->{injection_guard}) {
201 my $class = ref $_[0];
202 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
203 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
204 . "{injection_guard} attribute to ${class}->new()"
209 #======================================================================
211 #======================================================================
215 my $table = $self->_table(shift);
216 my $data = shift || return;
219 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
220 my ($sql, @bind) = $self->$method($data);
221 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
223 if ($options->{returning}) {
224 my ($s, @b) = $self->_insert_returning($options);
229 return wantarray ? ($sql, @bind) : $sql;
232 # So that subclasses can override INSERT ... RETURNING separately from
233 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
234 sub _insert_returning { shift->_returning(@_) }
237 my ($self, $options) = @_;
239 my $f = $options->{returning};
241 my ($sql, @bind) = $self->_render_expr(
242 $self->_expand_maybe_list_expr($f, undef, -ident)
245 ? $self->_sqlcase(' returning ') . $sql
246 : ($self->_sqlcase(' returning ').$sql, @bind);
249 sub _insert_HASHREF { # explicit list of fields and then values
250 my ($self, $data) = @_;
252 my @fields = sort keys %$data;
254 my ($sql, @bind) = $self->_insert_values($data);
257 $_ = $self->_quote($_) foreach @fields;
258 $sql = "( ".join(", ", @fields).") ".$sql;
260 return ($sql, @bind);
263 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
264 my ($self, $data) = @_;
266 # no names (arrayref) so can't generate bindtype
267 $self->{bindtype} ne 'columns'
268 or belch "can't do 'columns' bindtype when called with arrayref";
270 my (@values, @all_bind);
271 foreach my $value (@$data) {
272 my ($values, @bind) = $self->_insert_value(undef, $value);
273 push @values, $values;
274 push @all_bind, @bind;
276 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
277 return ($sql, @all_bind);
280 sub _insert_ARRAYREFREF { # literal SQL with bind
281 my ($self, $data) = @_;
283 my ($sql, @bind) = @${$data};
284 $self->_assert_bindval_matches_bindtype(@bind);
286 return ($sql, @bind);
290 sub _insert_SCALARREF { # literal SQL without bind
291 my ($self, $data) = @_;
297 my ($self, $data) = @_;
299 my (@values, @all_bind);
300 foreach my $column (sort keys %$data) {
301 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
302 push @values, $values;
303 push @all_bind, @bind;
305 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
306 return ($sql, @all_bind);
310 my ($self, $column, $v) = @_;
312 return $self->_render_expr(
313 $self->_expand_insert_value($column, $v)
317 sub _expand_insert_value {
318 my ($self, $column, $v) = @_;
320 if (ref($v) eq 'ARRAY') {
321 if ($self->{array_datatypes}) {
322 return +{ -bind => [ $column, $v ] };
324 my ($sql, @bind) = @$v;
325 $self->_assert_bindval_matches_bindtype(@bind);
326 return +{ -literal => $v };
328 if (ref($v) eq 'HASH') {
329 if (grep !/^-/, keys %$v) {
330 belch "HASH ref as bind value in insert is not supported";
331 return +{ -bind => [ $column, $v ] };
335 return +{ -bind => [ $column, undef ] };
337 local our $Cur_Col_Meta = $column;
338 return $self->_expand_expr($v);
343 #======================================================================
345 #======================================================================
350 my $table = $self->_table(shift);
351 my $data = shift || return;
355 # first build the 'SET' part of the sql statement
356 puke "Unsupported data type specified to \$sql->update"
357 unless ref $data eq 'HASH';
359 my ($sql, @all_bind) = $self->_update_set_values($data);
360 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
364 my($where_sql, @where_bind) = $self->where($where);
366 push @all_bind, @where_bind;
369 if ($options->{returning}) {
370 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
371 $sql .= $returning_sql;
372 push @all_bind, @returning_bind;
375 return wantarray ? ($sql, @all_bind) : $sql;
378 sub _update_set_values {
379 my ($self, $data) = @_;
381 return $self->_render_expr(
382 $self->_expand_update_set_values($data),
386 sub _expand_update_set_values {
387 my ($self, $data) = @_;
388 $self->_expand_maybe_list_expr( [
391 $set = { -bind => $_ } unless defined $set;
392 +{ -op => [ '=', { -ident => $k }, $set ] };
398 ? ($self->{array_datatypes}
399 ? [ $k, +{ -bind => [ $k, $v ] } ]
400 : [ $k, +{ -literal => $v } ])
402 local our $Cur_Col_Meta = $k;
403 [ $k, $self->_expand_expr($v) ]
410 # So that subclasses can override UPDATE ... RETURNING separately from
412 sub _update_returning { shift->_returning(@_) }
416 #======================================================================
418 #======================================================================
423 my $table = $self->_table(shift);
424 my $fields = shift || '*';
428 my ($fields_sql, @bind) = $self->_select_fields($fields);
430 my ($where_sql, @where_bind) = $self->where($where, $order);
431 push @bind, @where_bind;
433 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
434 $self->_sqlcase('from'), $table)
437 return wantarray ? ($sql, @bind) : $sql;
441 my ($self, $fields) = @_;
442 return $fields unless ref($fields);
443 return $self->_render_expr(
444 $self->_expand_maybe_list_expr($fields, undef, '-ident')
448 #======================================================================
450 #======================================================================
455 my $table = $self->_table(shift);
459 my($where_sql, @bind) = $self->where($where);
460 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
462 if ($options->{returning}) {
463 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
464 $sql .= $returning_sql;
465 push @bind, @returning_bind;
468 return wantarray ? ($sql, @bind) : $sql;
471 # So that subclasses can override DELETE ... RETURNING separately from
473 sub _delete_returning { shift->_returning(@_) }
477 #======================================================================
479 #======================================================================
483 # Finally, a separate routine just to handle WHERE clauses
485 my ($self, $where, $order) = @_;
487 local $self->{convert_where} = $self->{convert};
490 my ($sql, @bind) = defined($where)
491 ? $self->_recurse_where($where)
493 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
497 my ($order_sql, @order_bind) = $self->_order_by($order);
499 push @bind, @order_bind;
502 return wantarray ? ($sql, @bind) : $sql;
506 my ($self, $expr, $logic, $default_scalar_to) = @_;
507 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
508 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
509 return undef unless defined($expr);
510 if (ref($expr) eq 'HASH') {
511 if (keys %$expr > 1) {
515 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
519 return { -literal => [ '' ] } unless keys %$expr;
520 return $self->_expand_expr_hashpair(%$expr, $logic);
522 if (ref($expr) eq 'ARRAY') {
523 my $logic = lc($logic || $self->{logic});
524 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
528 (ref($_) eq 'ARRAY' and @$_)
529 or (ref($_) eq 'HASH' and %$_)
535 while (my ($el) = splice @expr, 0, 1) {
536 puke "Supplying an empty left hand side argument is not supported in array-pairs"
537 unless defined($el) and length($el);
538 my $elref = ref($el);
540 local $Expand_Depth = 0;
541 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
542 } elsif ($elref eq 'ARRAY') {
543 push(@res, $self->_expand_expr($el)) if @$el;
544 } elsif (my $l = is_literal_value($el)) {
545 push @res, { -literal => $l };
546 } elsif ($elref eq 'HASH') {
547 local $Expand_Depth = 0;
548 push @res, $self->_expand_expr($el) if %$el;
553 return { -op => [ $logic, @res ] };
555 if (my $literal = is_literal_value($expr)) {
556 return +{ -literal => $literal };
558 if (!ref($expr) or Scalar::Util::blessed($expr)) {
559 if (my $d = $Default_Scalar_To) {
560 return +{ $d => $expr };
562 if (my $m = our $Cur_Col_Meta) {
563 return +{ -bind => [ $m, $expr ] };
565 return +{ -value => $expr };
572 sub _expand_expr_hashpair {
573 my ($self, $k, $v, $logic) = @_;
574 unless (defined($k) and length($k)) {
575 if (defined($k) and my $literal = is_literal_value($v)) {
576 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
577 return { -literal => $literal };
579 puke "Supplying an empty left hand side argument is not supported";
582 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
583 if ($k =~ s/ [_\s]? \d+ $//x ) {
584 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
585 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
588 # DBIx::Class requires a nest warning to be emitted once but the private
589 # method it overrode to do so no longer exists
590 if (ref($self) =~ /^DBIx::Class::SQLMaker/) {
591 unless ($Nest_Warned) {
593 "-nest in search conditions is deprecated, you most probably wanted:\n"
594 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
599 return $self->_expand_expr($v);
603 return $self->_expand_expr($v);
605 puke "-bool => undef not supported" unless defined($v);
606 return { -ident => $v };
609 return { -op => [ 'not', $self->_expand_expr($v) ] };
611 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
614 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
617 if (my ($logic) = $k =~ /^-(and|or)$/i) {
618 if (ref($v) eq 'HASH') {
619 return $self->_expand_expr($v, $logic);
621 if (ref($v) eq 'ARRAY') {
622 return $self->_expand_expr($v, $logic);
627 $op =~ s/^-// if length($op) > 1;
629 # top level special ops are illegal in general
630 # note that, arguably, if it makes no sense at top level, it also
631 # makes no sense on the other side of an = sign or similar but DBIC
632 # gets disappointingly upset if I disallow it
634 (our $Expand_Depth) == 1
635 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
637 puke "Illegal use of top-level '-$op'"
639 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
640 return { -op => [ $op, $v ] };
643 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
644 return +{ -bind => [ $m, $v ] };
646 if (my $custom = $self->{expand_unary}{$k}) {
647 return $self->$custom($v);
649 if ($self->{node_types}{$k}) {
655 and (keys %$v)[0] =~ /^-/
657 my ($func) = $k =~ /^-(.*)$/;
658 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
659 return +{ -op => [ $func, $self->_expand_expr($v) ] };
661 return +{ -func => [ $func, $self->_expand_expr($v) ] };
663 if (!ref($v) or is_literal_value($v)) {
664 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
671 and exists $v->{-value}
672 and not defined $v->{-value}
675 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
677 if (!ref($v) or Scalar::Util::blessed($v)) {
678 my $d = our $Default_Scalar_To;
683 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
687 if (ref($v) eq 'HASH') {
691 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
695 return { -literal => [ '' ] } unless keys %$v;
699 $self->_assert_pass_injection_guard($vk);
700 if ($vk =~ s/ [_\s]? \d+ $//x ) {
701 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
702 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
704 if ($vk =~ /^(?:not[ _])?between$/) {
705 local our $Cur_Col_Meta = $k;
706 my @rhs = map $self->_expand_expr($_),
707 ref($vv) eq 'ARRAY' ? @$vv : $vv;
709 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
711 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
713 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
716 join(' ', split '_', $vk),
721 if ($vk =~ /^(?:not[ _])?in$/) {
722 if (my $literal = is_literal_value($vv)) {
723 my ($sql, @bind) = @$literal;
724 my $opened_sql = $self->_open_outer_paren($sql);
726 $vk, { -ident => $k },
727 [ { -literal => [ $opened_sql, @bind ] } ]
731 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
732 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
733 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
734 . 'will emit the logically correct SQL instead of raising this exception)'
736 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
738 my @rhs = map $self->_expand_expr($_),
739 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
740 map { defined($_) ? $_: puke($undef_err) }
741 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
742 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
745 join(' ', split '_', $vk),
750 if ($vk eq 'ident') {
751 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
752 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
760 if ($vk eq 'value') {
761 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
765 { -bind => [ $k, $vv ] }
768 if ($vk =~ /^is(?:[ _]not)?$/) {
769 puke "$vk can only take undef as argument"
773 and exists($vv->{-value})
774 and !defined($vv->{-value})
777 return +{ -op => [ $vk.' null', { -ident => $k } ] };
779 if ($vk =~ /^(and|or)$/) {
780 if (ref($vv) eq 'HASH') {
783 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
788 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
789 return { -op => [ $vk, { -ident => $k }, $vv ] };
791 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
795 { -op => [ $vk, $vv ] }
798 if (ref($vv) eq 'ARRAY') {
799 my ($logic, @values) = (
800 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
805 $vk =~ $self->{inequality_op}
806 or join(' ', split '_', $vk) =~ $self->{not_like_op}
808 if (lc($logic) eq '-or' and @values > 1) {
809 my $op = uc join ' ', split '_', $vk;
810 belch "A multi-element arrayref as an argument to the inequality op '$op' "
811 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
812 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
817 # try to DWIM on equality operators
818 my $op = join ' ', split '_', $vk;
820 $op =~ $self->{equality_op} ? $self->sqlfalse
821 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
822 : $op =~ $self->{inequality_op} ? $self->sqltrue
823 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
824 : puke "operator '$op' applied on an empty array (field '$k')";
828 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
836 and exists $vv->{-value}
837 and not defined $vv->{-value}
840 my $op = join ' ', split '_', $vk;
842 $op =~ /^not$/i ? 'is not' # legacy
843 : $op =~ $self->{equality_op} ? 'is'
844 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
845 : $op =~ $self->{inequality_op} ? 'is not'
846 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
847 : puke "unexpected operator '$op' with undef operand";
848 return +{ -op => [ $is.' null', { -ident => $k } ] };
850 local our $Cur_Col_Meta = $k;
854 $self->_expand_expr($vv)
857 if (ref($v) eq 'ARRAY') {
858 return $self->sqlfalse unless @$v;
859 $self->_debug("ARRAY($k) means distribute over elements");
861 $v->[0] =~ /^-((?:and|or))$/i
862 ? ($v = [ @{$v}[1..$#$v] ], $1)
863 : ($self->{logic} || 'or')
867 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
870 if (my $literal = is_literal_value($v)) {
872 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
875 my ($sql, @bind) = @$literal;
876 if ($self->{bindtype} eq 'columns') {
878 $self->_assert_bindval_matches_bindtype($_);
881 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
887 my ($self, $expr) = @_;
888 my ($k, $v, @rest) = %$expr;
890 if (my $meth = $self->{node_types}{$k}) {
891 return $self->$meth($v);
893 die "notreached: $k";
897 my ($self, $where, $logic) = @_;
899 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
901 # Special case: top level simple string treated as literal
903 my $where_exp = (ref($where)
904 ? $self->_expand_expr($where, $logic)
905 : { -literal => [ $where ] });
906 #::Dwarn([ EXPANDED => $where_exp ]);
908 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
910 # dispatch on appropriate method according to refkind of $where
911 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
913 # my ($sql, @bind) = $self->$method($where_exp, $logic);
915 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
916 # DBIx::Class used to call _recurse_where in scalar context
917 # something else might too...
919 return ($sql, @bind);
922 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
928 my ($self, $ident) = @_;
930 return $self->_convert($self->_quote($ident));
934 my ($self, $value) = @_;
936 return ($self->_convert('?'), $self->_bindtype(undef, $value));
939 my %unop_postfix = map +($_ => 1),
940 'is null', 'is not null',
948 my ($self, $args) = @_;
949 my ($left, $low, $high) = @$args;
950 my ($rhsql, @rhbind) = do {
952 puke "Single arg to between must be a literal"
953 unless $low->{-literal};
956 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
957 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
958 @{$l}[1..$#$l], @{$h}[1..$#$h])
961 my ($lhsql, @lhbind) = $self->_render_expr($left);
963 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
967 }), 'between', 'not between'),
971 my ($self, $args) = @_;
972 my ($lhs, $rhs) = @$args;
975 my ($sql, @bind) = $self->_render_expr($_);
976 push @in_bind, @bind;
979 my ($lhsql, @lbind) = $self->_render_expr($lhs);
981 $lhsql.' '.$self->_sqlcase($op).' ( '
992 my ($op, @args) = @$v;
993 $op =~ s/^-// if length($op) > 1;
995 if (my $h = $special{$op}) {
996 return $self->$h(\@args);
998 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
999 if ($us and @args > 1) {
1000 puke "Special op '${op}' requires first value to be identifier"
1001 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1002 local our $Expand_Depth = 1;
1003 return $self->${\($us->{handler})}($k, $op, $args[1]);
1005 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1006 return $self->${\($us->{handler})}($op, $args[0]);
1008 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1009 if (@args == 1 and $op !~ /^(and|or)$/) {
1010 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
1011 my $op_sql = $self->_sqlcase($final_op);
1013 $unop_postfix{lc($final_op)}
1014 ? "${expr_sql} ${op_sql}"
1015 : "${op_sql} ${expr_sql}"
1017 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1018 #} elsif (@args == 0) {
1021 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @args;
1022 return '' unless @parts;
1023 my $is_andor = !!($op =~ /^(and|or)$/);
1024 return @{$parts[0]} if $is_andor and @parts == 1;
1025 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1026 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
1031 map @{$_}[1..$#$_], @parts
1038 my ($self, $rest) = @_;
1039 my ($func, @args) = @$rest;
1043 push @arg_sql, shift @x;
1045 } map [ $self->_render_expr($_) ], @args;
1046 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1050 my ($self, $bind) = @_;
1051 return ($self->_convert('?'), $self->_bindtype(@$bind));
1054 sub _render_literal {
1055 my ($self, $literal) = @_;
1056 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1060 # Some databases (SQLite) treat col IN (1, 2) different from
1061 # col IN ( (1, 2) ). Use this to strip all outer parens while
1062 # adding them back in the corresponding method
1063 sub _open_outer_paren {
1064 my ($self, $sql) = @_;
1066 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1068 # there are closing parens inside, need the heavy duty machinery
1069 # to reevaluate the extraction starting from $sql (full reevaluation)
1070 if ($inner =~ /\)/) {
1071 require Text::Balanced;
1073 my (undef, $remainder) = do {
1074 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1076 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1079 # the entire expression needs to be a balanced bracketed thing
1080 # (after an extract no remainder sans trailing space)
1081 last if defined $remainder and $remainder =~ /\S/;
1091 #======================================================================
1093 #======================================================================
1095 sub _expand_order_by {
1096 my ($self, $arg) = @_;
1098 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1100 my $expander = sub {
1101 my ($self, $dir, $expr) = @_;
1102 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1103 foreach my $arg (@to_expand) {
1107 and grep /^-(asc|desc)$/, keys %$arg
1109 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1112 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1113 map $self->_expand_expr($_, undef, -ident),
1114 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1115 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1118 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1119 sub { shift->$expander(asc => @_) },
1120 sub { shift->$expander(desc => @_) },
1123 return $self->$expander(undef, $arg);
1127 my ($self, $arg) = @_;
1129 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1131 my ($sql, @bind) = $self->_render_expr($expanded);
1133 my $final_sql = $self->_sqlcase(' order by ').$sql;
1135 return wantarray ? ($final_sql, @bind) : $final_sql;
1138 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1140 sub _order_by_chunks {
1141 my ($self, $arg) = @_;
1143 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1145 return $self->_chunkify_order_by($expanded);
1148 sub _chunkify_order_by {
1149 my ($self, $expanded) = @_;
1151 return grep length, $self->_render_expr($expanded)
1152 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1155 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1156 if ($op->[0] eq ',') {
1157 return map $self->_chunkify_order_by($_), @{$op}[1..$#$op];
1160 return [ $self->_render_expr($_) ];
1164 #======================================================================
1165 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1166 #======================================================================
1171 ($self->_render_expr(
1172 $self->_expand_maybe_list_expr($from, undef, -ident)
1177 #======================================================================
1179 #======================================================================
1181 sub _expand_maybe_list_expr {
1182 my ($self, $expr, $logic, $default) = @_;
1184 if (ref($expr) eq 'ARRAY') {
1186 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1193 return $self->_expand_expr($e, $logic, $default);
1196 # highly optimized, as it's called way too often
1198 # my ($self, $label) = @_;
1200 return '' unless defined $_[1];
1201 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1202 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1204 unless ($_[0]->{quote_char}) {
1205 if (ref($_[1]) eq 'ARRAY') {
1206 return join($_[0]->{name_sep}||'.', @{$_[1]});
1208 $_[0]->_assert_pass_injection_guard($_[1]);
1213 my $qref = ref $_[0]->{quote_char};
1215 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1216 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1217 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1219 my $esc = $_[0]->{escape_char} || $r;
1221 # parts containing * are naturally unquoted
1223 $_[0]->{name_sep}||'',
1227 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1229 (ref($_[1]) eq 'ARRAY'
1233 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1241 # Conversion, if applicable
1243 #my ($self, $arg) = @_;
1244 if ($_[0]->{convert_where}) {
1245 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1252 #my ($self, $col, @vals) = @_;
1253 # called often - tighten code
1254 return $_[0]->{bindtype} eq 'columns'
1255 ? map {[$_[1], $_]} @_[2 .. $#_]
1260 # Dies if any element of @bind is not in [colname => value] format
1261 # if bindtype is 'columns'.
1262 sub _assert_bindval_matches_bindtype {
1263 # my ($self, @bind) = @_;
1265 if ($self->{bindtype} eq 'columns') {
1267 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1268 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1274 sub _join_sql_clauses {
1275 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1277 if (@$clauses_aref > 1) {
1278 my $join = " " . $self->_sqlcase($logic) . " ";
1279 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1280 return ($sql, @$bind_aref);
1282 elsif (@$clauses_aref) {
1283 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1286 return (); # if no SQL, ignore @$bind_aref
1291 # Fix SQL case, if so requested
1293 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1294 # don't touch the argument ... crooked logic, but let's not change it!
1295 return $_[0]->{case} ? $_[1] : uc($_[1]);
1299 #======================================================================
1300 # DISPATCHING FROM REFKIND
1301 #======================================================================
1304 my ($self, $data) = @_;
1306 return 'UNDEF' unless defined $data;
1308 # blessed objects are treated like scalars
1309 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1311 return 'SCALAR' unless $ref;
1314 while ($ref eq 'REF') {
1316 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1320 return ($ref||'SCALAR') . ('REF' x $n_steps);
1324 my ($self, $data) = @_;
1325 my @try = ($self->_refkind($data));
1326 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1327 push @try, 'FALLBACK';
1331 sub _METHOD_FOR_refkind {
1332 my ($self, $meth_prefix, $data) = @_;
1335 for (@{$self->_try_refkind($data)}) {
1336 $method = $self->can($meth_prefix."_".$_)
1340 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1344 sub _SWITCH_refkind {
1345 my ($self, $data, $dispatch_table) = @_;
1348 for (@{$self->_try_refkind($data)}) {
1349 $coderef = $dispatch_table->{$_}
1353 puke "no dispatch entry for ".$self->_refkind($data)
1362 #======================================================================
1363 # VALUES, GENERATE, AUTOLOAD
1364 #======================================================================
1366 # LDNOTE: original code from nwiger, didn't touch code in that section
1367 # I feel the AUTOLOAD stuff should not be the default, it should
1368 # only be activated on explicit demand by user.
1372 my $data = shift || return;
1373 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1374 unless ref $data eq 'HASH';
1377 foreach my $k (sort keys %$data) {
1378 my $v = $data->{$k};
1379 $self->_SWITCH_refkind($v, {
1381 if ($self->{array_datatypes}) { # array datatype
1382 push @all_bind, $self->_bindtype($k, $v);
1384 else { # literal SQL with bind
1385 my ($sql, @bind) = @$v;
1386 $self->_assert_bindval_matches_bindtype(@bind);
1387 push @all_bind, @bind;
1390 ARRAYREFREF => sub { # literal SQL with bind
1391 my ($sql, @bind) = @${$v};
1392 $self->_assert_bindval_matches_bindtype(@bind);
1393 push @all_bind, @bind;
1395 SCALARREF => sub { # literal SQL without bind
1397 SCALAR_or_UNDEF => sub {
1398 push @all_bind, $self->_bindtype($k, $v);
1409 my(@sql, @sqlq, @sqlv);
1413 if ($ref eq 'HASH') {
1414 for my $k (sort keys %$_) {
1417 my $label = $self->_quote($k);
1418 if ($r eq 'ARRAY') {
1419 # literal SQL with bind
1420 my ($sql, @bind) = @$v;
1421 $self->_assert_bindval_matches_bindtype(@bind);
1422 push @sqlq, "$label = $sql";
1424 } elsif ($r eq 'SCALAR') {
1425 # literal SQL without bind
1426 push @sqlq, "$label = $$v";
1428 push @sqlq, "$label = ?";
1429 push @sqlv, $self->_bindtype($k, $v);
1432 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1433 } elsif ($ref eq 'ARRAY') {
1434 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1437 if ($r eq 'ARRAY') { # literal SQL with bind
1438 my ($sql, @bind) = @$v;
1439 $self->_assert_bindval_matches_bindtype(@bind);
1442 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1443 # embedded literal SQL
1450 push @sql, '(' . join(', ', @sqlq) . ')';
1451 } elsif ($ref eq 'SCALAR') {
1455 # strings get case twiddled
1456 push @sql, $self->_sqlcase($_);
1460 my $sql = join ' ', @sql;
1462 # this is pretty tricky
1463 # if ask for an array, return ($stmt, @bind)
1464 # otherwise, s/?/shift @sqlv/ to put it inline
1466 return ($sql, @sqlv);
1468 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1469 ref $d ? $d->[1] : $d/e;
1478 # This allows us to check for a local, then _form, attr
1480 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1481 return $self->generate($name, @_);
1492 SQL::Abstract - Generate SQL from Perl data structures
1498 my $sql = SQL::Abstract->new;
1500 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1502 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1504 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1506 my($stmt, @bind) = $sql->delete($table, \%where);
1508 # Then, use these in your DBI statements
1509 my $sth = $dbh->prepare($stmt);
1510 $sth->execute(@bind);
1512 # Just generate the WHERE clause
1513 my($stmt, @bind) = $sql->where(\%where, $order);
1515 # Return values in the same order, for hashed queries
1516 # See PERFORMANCE section for more details
1517 my @bind = $sql->values(\%fieldvals);
1521 This module was inspired by the excellent L<DBIx::Abstract>.
1522 However, in using that module I found that what I really wanted
1523 to do was generate SQL, but still retain complete control over my
1524 statement handles and use the DBI interface. So, I set out to
1525 create an abstract SQL generation module.
1527 While based on the concepts used by L<DBIx::Abstract>, there are
1528 several important differences, especially when it comes to WHERE
1529 clauses. I have modified the concepts used to make the SQL easier
1530 to generate from Perl data structures and, IMO, more intuitive.
1531 The underlying idea is for this module to do what you mean, based
1532 on the data structures you provide it. The big advantage is that
1533 you don't have to modify your code every time your data changes,
1534 as this module figures it out.
1536 To begin with, an SQL INSERT is as easy as just specifying a hash
1537 of C<key=value> pairs:
1540 name => 'Jimbo Bobson',
1541 phone => '123-456-7890',
1542 address => '42 Sister Lane',
1543 city => 'St. Louis',
1544 state => 'Louisiana',
1547 The SQL can then be generated with this:
1549 my($stmt, @bind) = $sql->insert('people', \%data);
1551 Which would give you something like this:
1553 $stmt = "INSERT INTO people
1554 (address, city, name, phone, state)
1555 VALUES (?, ?, ?, ?, ?)";
1556 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1557 '123-456-7890', 'Louisiana');
1559 These are then used directly in your DBI code:
1561 my $sth = $dbh->prepare($stmt);
1562 $sth->execute(@bind);
1564 =head2 Inserting and Updating Arrays
1566 If your database has array types (like for example Postgres),
1567 activate the special option C<< array_datatypes => 1 >>
1568 when creating the C<SQL::Abstract> object.
1569 Then you may use an arrayref to insert and update database array types:
1571 my $sql = SQL::Abstract->new(array_datatypes => 1);
1573 planets => [qw/Mercury Venus Earth Mars/]
1576 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1580 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1582 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1585 =head2 Inserting and Updating SQL
1587 In order to apply SQL functions to elements of your C<%data> you may
1588 specify a reference to an arrayref for the given hash value. For example,
1589 if you need to execute the Oracle C<to_date> function on a value, you can
1590 say something like this:
1594 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1597 The first value in the array is the actual SQL. Any other values are
1598 optional and would be included in the bind values array. This gives
1601 my($stmt, @bind) = $sql->insert('people', \%data);
1603 $stmt = "INSERT INTO people (name, date_entered)
1604 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1605 @bind = ('Bill', '03/02/2003');
1607 An UPDATE is just as easy, all you change is the name of the function:
1609 my($stmt, @bind) = $sql->update('people', \%data);
1611 Notice that your C<%data> isn't touched; the module will generate
1612 the appropriately quirky SQL for you automatically. Usually you'll
1613 want to specify a WHERE clause for your UPDATE, though, which is
1614 where handling C<%where> hashes comes in handy...
1616 =head2 Complex where statements
1618 This module can generate pretty complicated WHERE statements
1619 easily. For example, simple C<key=value> pairs are taken to mean
1620 equality, and if you want to see if a field is within a set
1621 of values, you can use an arrayref. Let's say we wanted to
1622 SELECT some data based on this criteria:
1625 requestor => 'inna',
1626 worker => ['nwiger', 'rcwe', 'sfz'],
1627 status => { '!=', 'completed' }
1630 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1632 The above would give you something like this:
1634 $stmt = "SELECT * FROM tickets WHERE
1635 ( requestor = ? ) AND ( status != ? )
1636 AND ( worker = ? OR worker = ? OR worker = ? )";
1637 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1639 Which you could then use in DBI code like so:
1641 my $sth = $dbh->prepare($stmt);
1642 $sth->execute(@bind);
1648 The methods are simple. There's one for every major SQL operation,
1649 and a constructor you use first. The arguments are specified in a
1650 similar order for each method (table, then fields, then a where
1651 clause) to try and simplify things.
1653 =head2 new(option => 'value')
1655 The C<new()> function takes a list of options and values, and returns
1656 a new B<SQL::Abstract> object which can then be used to generate SQL
1657 through the methods below. The options accepted are:
1663 If set to 'lower', then SQL will be generated in all lowercase. By
1664 default SQL is generated in "textbook" case meaning something like:
1666 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1668 Any setting other than 'lower' is ignored.
1672 This determines what the default comparison operator is. By default
1673 it is C<=>, meaning that a hash like this:
1675 %where = (name => 'nwiger', email => 'nate@wiger.org');
1677 Will generate SQL like this:
1679 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1681 However, you may want loose comparisons by default, so if you set
1682 C<cmp> to C<like> you would get SQL such as:
1684 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1686 You can also override the comparison on an individual basis - see
1687 the huge section on L</"WHERE CLAUSES"> at the bottom.
1689 =item sqltrue, sqlfalse
1691 Expressions for inserting boolean values within SQL statements.
1692 By default these are C<1=1> and C<1=0>. They are used
1693 by the special operators C<-in> and C<-not_in> for generating
1694 correct SQL even when the argument is an empty array (see below).
1698 This determines the default logical operator for multiple WHERE
1699 statements in arrays or hashes. If absent, the default logic is "or"
1700 for arrays, and "and" for hashes. This means that a WHERE
1704 event_date => {'>=', '2/13/99'},
1705 event_date => {'<=', '4/24/03'},
1708 will generate SQL like this:
1710 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1712 This is probably not what you want given this query, though (look
1713 at the dates). To change the "OR" to an "AND", simply specify:
1715 my $sql = SQL::Abstract->new(logic => 'and');
1717 Which will change the above C<WHERE> to:
1719 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1721 The logic can also be changed locally by inserting
1722 a modifier in front of an arrayref:
1724 @where = (-and => [event_date => {'>=', '2/13/99'},
1725 event_date => {'<=', '4/24/03'} ]);
1727 See the L</"WHERE CLAUSES"> section for explanations.
1731 This will automatically convert comparisons using the specified SQL
1732 function for both column and value. This is mostly used with an argument
1733 of C<upper> or C<lower>, so that the SQL will have the effect of
1734 case-insensitive "searches". For example, this:
1736 $sql = SQL::Abstract->new(convert => 'upper');
1737 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1739 Will turn out the following SQL:
1741 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1743 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1744 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1745 not validate this option; it will just pass through what you specify verbatim).
1749 This is a kludge because many databases suck. For example, you can't
1750 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1751 Instead, you have to use C<bind_param()>:
1753 $sth->bind_param(1, 'reg data');
1754 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1756 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1757 which loses track of which field each slot refers to. Fear not.
1759 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1760 Currently, you can specify either C<normal> (default) or C<columns>. If you
1761 specify C<columns>, you will get an array that looks like this:
1763 my $sql = SQL::Abstract->new(bindtype => 'columns');
1764 my($stmt, @bind) = $sql->insert(...);
1767 [ 'column1', 'value1' ],
1768 [ 'column2', 'value2' ],
1769 [ 'column3', 'value3' ],
1772 You can then iterate through this manually, using DBI's C<bind_param()>.
1774 $sth->prepare($stmt);
1777 my($col, $data) = @$_;
1778 if ($col eq 'details' || $col eq 'comments') {
1779 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1780 } elsif ($col eq 'image') {
1781 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1783 $sth->bind_param($i, $data);
1787 $sth->execute; # execute without @bind now
1789 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1790 Basically, the advantage is still that you don't have to care which fields
1791 are or are not included. You could wrap that above C<for> loop in a simple
1792 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1793 get a layer of abstraction over manual SQL specification.
1795 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1796 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1797 will expect the bind values in this format.
1801 This is the character that a table or column name will be quoted
1802 with. By default this is an empty string, but you could set it to
1803 the character C<`>, to generate SQL like this:
1805 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1807 Alternatively, you can supply an array ref of two items, the first being the left
1808 hand quote character, and the second the right hand quote character. For
1809 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1810 that generates SQL like this:
1812 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1814 Quoting is useful if you have tables or columns names that are reserved
1815 words in your database's SQL dialect.
1819 This is the character that will be used to escape L</quote_char>s appearing
1820 in an identifier before it has been quoted.
1822 The parameter default in case of a single L</quote_char> character is the quote
1825 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1826 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1827 of the B<opening (left)> L</quote_char> within the identifier are currently left
1828 untouched. The default for opening-closing-style quotes may change in future
1829 versions, thus you are B<strongly encouraged> to specify the escape character
1834 This is the character that separates a table and column name. It is
1835 necessary to specify this when the C<quote_char> option is selected,
1836 so that tables and column names can be individually quoted like this:
1838 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1840 =item injection_guard
1842 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1843 column name specified in a query structure. This is a safety mechanism to avoid
1844 injection attacks when mishandling user input e.g.:
1846 my %condition_as_column_value_pairs = get_values_from_user();
1847 $sqla->select( ... , \%condition_as_column_value_pairs );
1849 If the expression matches an exception is thrown. Note that literal SQL
1850 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1852 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1854 =item array_datatypes
1856 When this option is true, arrayrefs in INSERT or UPDATE are
1857 interpreted as array datatypes and are passed directly
1859 When this option is false, arrayrefs are interpreted
1860 as literal SQL, just like refs to arrayrefs
1861 (but this behavior is for backwards compatibility; when writing
1862 new queries, use the "reference to arrayref" syntax
1868 Takes a reference to a list of "special operators"
1869 to extend the syntax understood by L<SQL::Abstract>.
1870 See section L</"SPECIAL OPERATORS"> for details.
1874 Takes a reference to a list of "unary operators"
1875 to extend the syntax understood by L<SQL::Abstract>.
1876 See section L</"UNARY OPERATORS"> for details.
1882 =head2 insert($table, \@values || \%fieldvals, \%options)
1884 This is the simplest function. You simply give it a table name
1885 and either an arrayref of values or hashref of field/value pairs.
1886 It returns an SQL INSERT statement and a list of bind values.
1887 See the sections on L</"Inserting and Updating Arrays"> and
1888 L</"Inserting and Updating SQL"> for information on how to insert
1889 with those data types.
1891 The optional C<\%options> hash reference may contain additional
1892 options to generate the insert SQL. Currently supported options
1899 Takes either a scalar of raw SQL fields, or an array reference of
1900 field names, and adds on an SQL C<RETURNING> statement at the end.
1901 This allows you to return data generated by the insert statement
1902 (such as row IDs) without performing another C<SELECT> statement.
1903 Note, however, this is not part of the SQL standard and may not
1904 be supported by all database engines.
1908 =head2 update($table, \%fieldvals, \%where, \%options)
1910 This takes a table, hashref of field/value pairs, and an optional
1911 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1913 See the sections on L</"Inserting and Updating Arrays"> and
1914 L</"Inserting and Updating SQL"> for information on how to insert
1915 with those data types.
1917 The optional C<\%options> hash reference may contain additional
1918 options to generate the update SQL. Currently supported options
1925 See the C<returning> option to
1926 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1930 =head2 select($source, $fields, $where, $order)
1932 This returns a SQL SELECT statement and associated list of bind values, as
1933 specified by the arguments:
1939 Specification of the 'FROM' part of the statement.
1940 The argument can be either a plain scalar (interpreted as a table
1941 name, will be quoted), or an arrayref (interpreted as a list
1942 of table names, joined by commas, quoted), or a scalarref
1943 (literal SQL, not quoted).
1947 Specification of the list of fields to retrieve from
1949 The argument can be either an arrayref (interpreted as a list
1950 of field names, will be joined by commas and quoted), or a
1951 plain scalar (literal SQL, not quoted).
1952 Please observe that this API is not as flexible as that of
1953 the first argument C<$source>, for backwards compatibility reasons.
1957 Optional argument to specify the WHERE part of the query.
1958 The argument is most often a hashref, but can also be
1959 an arrayref or plain scalar --
1960 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1964 Optional argument to specify the ORDER BY part of the query.
1965 The argument can be a scalar, a hashref or an arrayref
1966 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1972 =head2 delete($table, \%where, \%options)
1974 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1975 It returns an SQL DELETE statement and list of bind values.
1977 The optional C<\%options> hash reference may contain additional
1978 options to generate the delete SQL. Currently supported options
1985 See the C<returning> option to
1986 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1990 =head2 where(\%where, $order)
1992 This is used to generate just the WHERE clause. For example,
1993 if you have an arbitrary data structure and know what the
1994 rest of your SQL is going to look like, but want an easy way
1995 to produce a WHERE clause, use this. It returns an SQL WHERE
1996 clause and list of bind values.
1999 =head2 values(\%data)
2001 This just returns the values from the hash C<%data>, in the same
2002 order that would be returned from any of the other above queries.
2003 Using this allows you to markedly speed up your queries if you
2004 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2006 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2008 Warning: This is an experimental method and subject to change.
2010 This returns arbitrarily generated SQL. It's a really basic shortcut.
2011 It will return two different things, depending on return context:
2013 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2014 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2016 These would return the following:
2018 # First calling form
2019 $stmt = "CREATE TABLE test (?, ?)";
2020 @bind = (field1, field2);
2022 # Second calling form
2023 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2025 Depending on what you're trying to do, it's up to you to choose the correct
2026 format. In this example, the second form is what you would want.
2030 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2034 ALTER SESSION SET nls_date_format = 'MM/YY'
2036 You get the idea. Strings get their case twiddled, but everything
2037 else remains verbatim.
2039 =head1 EXPORTABLE FUNCTIONS
2041 =head2 is_plain_value
2043 Determines if the supplied argument is a plain value as understood by this
2048 =item * The value is C<undef>
2050 =item * The value is a non-reference
2052 =item * The value is an object with stringification overloading
2054 =item * The value is of the form C<< { -value => $anything } >>
2058 On failure returns C<undef>, on success returns a B<scalar> reference
2059 to the original supplied argument.
2065 The stringification overloading detection is rather advanced: it takes
2066 into consideration not only the presence of a C<""> overload, but if that
2067 fails also checks for enabled
2068 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2069 on either C<0+> or C<bool>.
2071 Unfortunately testing in the field indicates that this
2072 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2073 but only when very large numbers of stringifying objects are involved.
2074 At the time of writing ( Sep 2014 ) there is no clear explanation of
2075 the direct cause, nor is there a manageably small test case that reliably
2076 reproduces the problem.
2078 If you encounter any of the following exceptions in B<random places within
2079 your application stack> - this module may be to blame:
2081 Operation "ne": no method found,
2082 left argument in overloaded package <something>,
2083 right argument in overloaded package <something>
2087 Stub found while resolving method "???" overloading """" in package <something>
2089 If you fall victim to the above - please attempt to reduce the problem
2090 to something that could be sent to the L<SQL::Abstract developers
2091 |DBIx::Class/GETTING HELP/SUPPORT>
2092 (either publicly or privately). As a workaround in the meantime you can
2093 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2094 value, which will most likely eliminate your problem (at the expense of
2095 not being able to properly detect exotic forms of stringification).
2097 This notice and environment variable will be removed in a future version,
2098 as soon as the underlying problem is found and a reliable workaround is
2103 =head2 is_literal_value
2105 Determines if the supplied argument is a literal value as understood by this
2110 =item * C<\$sql_string>
2112 =item * C<\[ $sql_string, @bind_values ]>
2116 On failure returns C<undef>, on success returns an B<array> reference
2117 containing the unpacked version of the supplied literal SQL and bind values.
2119 =head1 WHERE CLAUSES
2123 This module uses a variation on the idea from L<DBIx::Abstract>. It
2124 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2125 module is that things in arrays are OR'ed, and things in hashes
2128 The easiest way to explain is to show lots of examples. After
2129 each C<%where> hash shown, it is assumed you used:
2131 my($stmt, @bind) = $sql->where(\%where);
2133 However, note that the C<%where> hash can be used directly in any
2134 of the other functions as well, as described above.
2136 =head2 Key-value pairs
2138 So, let's get started. To begin, a simple hash:
2142 status => 'completed'
2145 Is converted to SQL C<key = val> statements:
2147 $stmt = "WHERE user = ? AND status = ?";
2148 @bind = ('nwiger', 'completed');
2150 One common thing I end up doing is having a list of values that
2151 a field can be in. To do this, simply specify a list inside of
2156 status => ['assigned', 'in-progress', 'pending'];
2159 This simple code will create the following:
2161 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2162 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2164 A field associated to an empty arrayref will be considered a
2165 logical false and will generate 0=1.
2167 =head2 Tests for NULL values
2169 If the value part is C<undef> then this is converted to SQL <IS NULL>
2178 $stmt = "WHERE user = ? AND status IS NULL";
2181 To test if a column IS NOT NULL:
2185 status => { '!=', undef },
2188 =head2 Specific comparison operators
2190 If you want to specify a different type of operator for your comparison,
2191 you can use a hashref for a given column:
2195 status => { '!=', 'completed' }
2198 Which would generate:
2200 $stmt = "WHERE user = ? AND status != ?";
2201 @bind = ('nwiger', 'completed');
2203 To test against multiple values, just enclose the values in an arrayref:
2205 status => { '=', ['assigned', 'in-progress', 'pending'] };
2207 Which would give you:
2209 "WHERE status = ? OR status = ? OR status = ?"
2212 The hashref can also contain multiple pairs, in which case it is expanded
2213 into an C<AND> of its elements:
2217 status => { '!=', 'completed', -not_like => 'pending%' }
2220 # Or more dynamically, like from a form
2221 $where{user} = 'nwiger';
2222 $where{status}{'!='} = 'completed';
2223 $where{status}{'-not_like'} = 'pending%';
2225 # Both generate this
2226 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2227 @bind = ('nwiger', 'completed', 'pending%');
2230 To get an OR instead, you can combine it with the arrayref idea:
2234 priority => [ { '=', 2 }, { '>', 5 } ]
2237 Which would generate:
2239 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2240 @bind = ('2', '5', 'nwiger');
2242 If you want to include literal SQL (with or without bind values), just use a
2243 scalar reference or reference to an arrayref as the value:
2246 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2247 date_expires => { '<' => \"now()" }
2250 Which would generate:
2252 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2253 @bind = ('11/26/2008');
2256 =head2 Logic and nesting operators
2258 In the example above,
2259 there is a subtle trap if you want to say something like
2260 this (notice the C<AND>):
2262 WHERE priority != ? AND priority != ?
2264 Because, in Perl you I<can't> do this:
2266 priority => { '!=' => 2, '!=' => 1 }
2268 As the second C<!=> key will obliterate the first. The solution
2269 is to use the special C<-modifier> form inside an arrayref:
2271 priority => [ -and => {'!=', 2},
2275 Normally, these would be joined by C<OR>, but the modifier tells it
2276 to use C<AND> instead. (Hint: You can use this in conjunction with the
2277 C<logic> option to C<new()> in order to change the way your queries
2278 work by default.) B<Important:> Note that the C<-modifier> goes
2279 B<INSIDE> the arrayref, as an extra first element. This will
2280 B<NOT> do what you think it might:
2282 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2284 Here is a quick list of equivalencies, since there is some overlap:
2287 status => {'!=', 'completed', 'not like', 'pending%' }
2288 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2291 status => {'=', ['assigned', 'in-progress']}
2292 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2293 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2297 =head2 Special operators: IN, BETWEEN, etc.
2299 You can also use the hashref format to compare a list of fields using the
2300 C<IN> comparison operator, by specifying the list as an arrayref:
2303 status => 'completed',
2304 reportid => { -in => [567, 2335, 2] }
2307 Which would generate:
2309 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2310 @bind = ('completed', '567', '2335', '2');
2312 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2315 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2316 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2317 'sqltrue' (by default: C<1=1>).
2319 In addition to the array you can supply a chunk of literal sql or
2320 literal sql with bind:
2323 customer => { -in => \[
2324 'SELECT cust_id FROM cust WHERE balance > ?',
2327 status => { -in => \'SELECT status_codes FROM states' },
2333 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2334 AND status IN ( SELECT status_codes FROM states )
2338 Finally, if the argument to C<-in> is not a reference, it will be
2339 treated as a single-element array.
2341 Another pair of operators is C<-between> and C<-not_between>,
2342 used with an arrayref of two values:
2346 completion_date => {
2347 -not_between => ['2002-10-01', '2003-02-06']
2353 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2355 Just like with C<-in> all plausible combinations of literal SQL
2359 start0 => { -between => [ 1, 2 ] },
2360 start1 => { -between => \["? AND ?", 1, 2] },
2361 start2 => { -between => \"lower(x) AND upper(y)" },
2362 start3 => { -between => [
2364 \["upper(?)", 'stuff' ],
2371 ( start0 BETWEEN ? AND ? )
2372 AND ( start1 BETWEEN ? AND ? )
2373 AND ( start2 BETWEEN lower(x) AND upper(y) )
2374 AND ( start3 BETWEEN lower(x) AND upper(?) )
2376 @bind = (1, 2, 1, 2, 'stuff');
2379 These are the two builtin "special operators"; but the
2380 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2382 =head2 Unary operators: bool
2384 If you wish to test against boolean columns or functions within your
2385 database you can use the C<-bool> and C<-not_bool> operators. For
2386 example to test the column C<is_user> being true and the column
2387 C<is_enabled> being false you would use:-
2391 -not_bool => 'is_enabled',
2396 WHERE is_user AND NOT is_enabled
2398 If a more complex combination is required, testing more conditions,
2399 then you should use the and/or operators:-
2404 -not_bool => { two=> { -rlike => 'bar' } },
2405 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2416 (NOT ( three = ? OR three > ? ))
2419 =head2 Nested conditions, -and/-or prefixes
2421 So far, we've seen how multiple conditions are joined with a top-level
2422 C<AND>. We can change this by putting the different conditions we want in
2423 hashes and then putting those hashes in an array. For example:
2428 status => { -like => ['pending%', 'dispatched'] },
2432 status => 'unassigned',
2436 This data structure would create the following:
2438 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2439 OR ( user = ? AND status = ? ) )";
2440 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2443 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2444 to change the logic inside:
2450 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2451 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2458 $stmt = "WHERE ( user = ?
2459 AND ( ( workhrs > ? AND geo = ? )
2460 OR ( workhrs < ? OR geo = ? ) ) )";
2461 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2463 =head3 Algebraic inconsistency, for historical reasons
2465 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2466 operator goes C<outside> of the nested structure; whereas when connecting
2467 several constraints on one column, the C<-and> operator goes
2468 C<inside> the arrayref. Here is an example combining both features:
2471 -and => [a => 1, b => 2],
2472 -or => [c => 3, d => 4],
2473 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2478 WHERE ( ( ( a = ? AND b = ? )
2479 OR ( c = ? OR d = ? )
2480 OR ( e LIKE ? AND e LIKE ? ) ) )
2482 This difference in syntax is unfortunate but must be preserved for
2483 historical reasons. So be careful: the two examples below would
2484 seem algebraically equivalent, but they are not
2487 { -like => 'foo%' },
2488 { -like => '%bar' },
2490 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2493 { col => { -like => 'foo%' } },
2494 { col => { -like => '%bar' } },
2496 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2499 =head2 Literal SQL and value type operators
2501 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2502 side" is a column name and the "right side" is a value (normally rendered as
2503 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2504 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2505 alter this behavior. There are several ways of doing so.
2509 This is a virtual operator that signals the string to its right side is an
2510 identifier (a column name) and not a value. For example to compare two
2511 columns you would write:
2514 priority => { '<', 2 },
2515 requestor => { -ident => 'submitter' },
2520 $stmt = "WHERE priority < ? AND requestor = submitter";
2523 If you are maintaining legacy code you may see a different construct as
2524 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2529 This is a virtual operator that signals that the construct to its right side
2530 is a value to be passed to DBI. This is for example necessary when you want
2531 to write a where clause against an array (for RDBMS that support such
2532 datatypes). For example:
2535 array => { -value => [1, 2, 3] }
2540 $stmt = 'WHERE array = ?';
2541 @bind = ([1, 2, 3]);
2543 Note that if you were to simply say:
2549 the result would probably not be what you wanted:
2551 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2556 Finally, sometimes only literal SQL will do. To include a random snippet
2557 of SQL verbatim, you specify it as a scalar reference. Consider this only
2558 as a last resort. Usually there is a better way. For example:
2561 priority => { '<', 2 },
2562 requestor => { -in => \'(SELECT name FROM hitmen)' },
2567 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2570 Note that in this example, you only get one bind parameter back, since
2571 the verbatim SQL is passed as part of the statement.
2575 Never use untrusted input as a literal SQL argument - this is a massive
2576 security risk (there is no way to check literal snippets for SQL
2577 injections and other nastyness). If you need to deal with untrusted input
2578 use literal SQL with placeholders as described next.
2580 =head3 Literal SQL with placeholders and bind values (subqueries)
2582 If the literal SQL to be inserted has placeholders and bind values,
2583 use a reference to an arrayref (yes this is a double reference --
2584 not so common, but perfectly legal Perl). For example, to find a date
2585 in Postgres you can use something like this:
2588 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2593 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2596 Note that you must pass the bind values in the same format as they are returned
2597 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2598 to C<columns>, you must provide the bind values in the
2599 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2600 scalar value; most commonly the column name, but you can use any scalar value
2601 (including references and blessed references), L<SQL::Abstract> will simply
2602 pass it through intact. So if C<bindtype> is set to C<columns> the above
2603 example will look like:
2606 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2609 Literal SQL is especially useful for nesting parenthesized clauses in the
2610 main SQL query. Here is a first example:
2612 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2616 bar => \["IN ($sub_stmt)" => @sub_bind],
2621 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2622 WHERE c2 < ? AND c3 LIKE ?))";
2623 @bind = (1234, 100, "foo%");
2625 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2626 are expressed in the same way. Of course the C<$sub_stmt> and
2627 its associated bind values can be generated through a former call
2630 my ($sub_stmt, @sub_bind)
2631 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2632 c3 => {-like => "foo%"}});
2635 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2638 In the examples above, the subquery was used as an operator on a column;
2639 but the same principle also applies for a clause within the main C<%where>
2640 hash, like an EXISTS subquery:
2642 my ($sub_stmt, @sub_bind)
2643 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2644 my %where = ( -and => [
2646 \["EXISTS ($sub_stmt)" => @sub_bind],
2651 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2652 WHERE c1 = ? AND c2 > t0.c0))";
2656 Observe that the condition on C<c2> in the subquery refers to
2657 column C<t0.c0> of the main query: this is I<not> a bind
2658 value, so we have to express it through a scalar ref.
2659 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2660 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2661 what we wanted here.
2663 Finally, here is an example where a subquery is used
2664 for expressing unary negation:
2666 my ($sub_stmt, @sub_bind)
2667 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2668 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2670 lname => {like => '%son%'},
2671 \["NOT ($sub_stmt)" => @sub_bind],
2676 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2677 @bind = ('%son%', 10, 20)
2679 =head3 Deprecated usage of Literal SQL
2681 Below are some examples of archaic use of literal SQL. It is shown only as
2682 reference for those who deal with legacy code. Each example has a much
2683 better, cleaner and safer alternative that users should opt for in new code.
2689 my %where = ( requestor => \'IS NOT NULL' )
2691 $stmt = "WHERE requestor IS NOT NULL"
2693 This used to be the way of generating NULL comparisons, before the handling
2694 of C<undef> got formalized. For new code please use the superior syntax as
2695 described in L</Tests for NULL values>.
2699 my %where = ( requestor => \'= submitter' )
2701 $stmt = "WHERE requestor = submitter"
2703 This used to be the only way to compare columns. Use the superior L</-ident>
2704 method for all new code. For example an identifier declared in such a way
2705 will be properly quoted if L</quote_char> is properly set, while the legacy
2706 form will remain as supplied.
2710 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2712 $stmt = "WHERE completed > ? AND is_ready"
2713 @bind = ('2012-12-21')
2715 Using an empty string literal used to be the only way to express a boolean.
2716 For all new code please use the much more readable
2717 L<-bool|/Unary operators: bool> operator.
2723 These pages could go on for a while, since the nesting of the data
2724 structures this module can handle are pretty much unlimited (the
2725 module implements the C<WHERE> expansion as a recursive function
2726 internally). Your best bet is to "play around" with the module a
2727 little to see how the data structures behave, and choose the best
2728 format for your data based on that.
2730 And of course, all the values above will probably be replaced with
2731 variables gotten from forms or the command line. After all, if you
2732 knew everything ahead of time, you wouldn't have to worry about
2733 dynamically-generating SQL and could just hardwire it into your
2736 =head1 ORDER BY CLAUSES
2738 Some functions take an order by clause. This can either be a scalar (just a
2739 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2740 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2743 Given | Will Generate
2744 ---------------------------------------------------------------
2746 'colA' | ORDER BY colA
2748 [qw/colA colB/] | ORDER BY colA, colB
2750 {-asc => 'colA'} | ORDER BY colA ASC
2752 {-desc => 'colB'} | ORDER BY colB DESC
2754 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2756 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2758 \'colA DESC' | ORDER BY colA DESC
2760 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2761 | /* ...with $x bound to ? */
2764 { -asc => 'colA' }, | colA ASC,
2765 { -desc => [qw/colB/] }, | colB DESC,
2766 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2767 \'colE DESC', | colE DESC,
2768 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2769 ] | /* ...with $x bound to ? */
2770 ===============================================================
2774 =head1 SPECIAL OPERATORS
2776 my $sqlmaker = SQL::Abstract->new(special_ops => [
2780 my ($self, $field, $op, $arg) = @_;
2786 handler => 'method_name',
2790 A "special operator" is a SQL syntactic clause that can be
2791 applied to a field, instead of a usual binary operator.
2794 WHERE field IN (?, ?, ?)
2795 WHERE field BETWEEN ? AND ?
2796 WHERE MATCH(field) AGAINST (?, ?)
2798 Special operators IN and BETWEEN are fairly standard and therefore
2799 are builtin within C<SQL::Abstract> (as the overridable methods
2800 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2801 like the MATCH .. AGAINST example above which is specific to MySQL,
2802 you can write your own operator handlers - supply a C<special_ops>
2803 argument to the C<new> method. That argument takes an arrayref of
2804 operator definitions; each operator definition is a hashref with two
2811 the regular expression to match the operator
2815 Either a coderef or a plain scalar method name. In both cases
2816 the expected return is C<< ($sql, @bind) >>.
2818 When supplied with a method name, it is simply called on the
2819 L<SQL::Abstract> object as:
2821 $self->$method_name($field, $op, $arg)
2825 $field is the LHS of the operator
2826 $op is the part that matched the handler regex
2829 When supplied with a coderef, it is called as:
2831 $coderef->($self, $field, $op, $arg)
2836 For example, here is an implementation
2837 of the MATCH .. AGAINST syntax for MySQL
2839 my $sqlmaker = SQL::Abstract->new(special_ops => [
2841 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2842 {regex => qr/^match$/i,
2844 my ($self, $field, $op, $arg) = @_;
2845 $arg = [$arg] if not ref $arg;
2846 my $label = $self->_quote($field);
2847 my ($placeholder) = $self->_convert('?');
2848 my $placeholders = join ", ", (($placeholder) x @$arg);
2849 my $sql = $self->_sqlcase('match') . " ($label) "
2850 . $self->_sqlcase('against') . " ($placeholders) ";
2851 my @bind = $self->_bindtype($field, @$arg);
2852 return ($sql, @bind);
2859 =head1 UNARY OPERATORS
2861 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2865 my ($self, $op, $arg) = @_;
2871 handler => 'method_name',
2875 A "unary operator" is a SQL syntactic clause that can be
2876 applied to a field - the operator goes before the field
2878 You can write your own operator handlers - supply a C<unary_ops>
2879 argument to the C<new> method. That argument takes an arrayref of
2880 operator definitions; each operator definition is a hashref with two
2887 the regular expression to match the operator
2891 Either a coderef or a plain scalar method name. In both cases
2892 the expected return is C<< $sql >>.
2894 When supplied with a method name, it is simply called on the
2895 L<SQL::Abstract> object as:
2897 $self->$method_name($op, $arg)
2901 $op is the part that matched the handler regex
2902 $arg is the RHS or argument of the operator
2904 When supplied with a coderef, it is called as:
2906 $coderef->($self, $op, $arg)
2914 Thanks to some benchmarking by Mark Stosberg, it turns out that
2915 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2916 I must admit this wasn't an intentional design issue, but it's a
2917 byproduct of the fact that you get to control your C<DBI> handles
2920 To maximize performance, use a code snippet like the following:
2922 # prepare a statement handle using the first row
2923 # and then reuse it for the rest of the rows
2925 for my $href (@array_of_hashrefs) {
2926 $stmt ||= $sql->insert('table', $href);
2927 $sth ||= $dbh->prepare($stmt);
2928 $sth->execute($sql->values($href));
2931 The reason this works is because the keys in your C<$href> are sorted
2932 internally by B<SQL::Abstract>. Thus, as long as your data retains
2933 the same structure, you only have to generate the SQL the first time
2934 around. On subsequent queries, simply use the C<values> function provided
2935 by this module to return your values in the correct order.
2937 However this depends on the values having the same type - if, for
2938 example, the values of a where clause may either have values
2939 (resulting in sql of the form C<column = ?> with a single bind
2940 value), or alternatively the values might be C<undef> (resulting in
2941 sql of the form C<column IS NULL> with no bind value) then the
2942 caching technique suggested will not work.
2946 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2947 really like this part (I do, at least). Building up a complex query
2948 can be as simple as the following:
2955 use CGI::FormBuilder;
2958 my $form = CGI::FormBuilder->new(...);
2959 my $sql = SQL::Abstract->new;
2961 if ($form->submitted) {
2962 my $field = $form->field;
2963 my $id = delete $field->{id};
2964 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2967 Of course, you would still have to connect using C<DBI> to run the
2968 query, but the point is that if you make your form look like your
2969 table, the actual query script can be extremely simplistic.
2971 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2972 a fast interface to returning and formatting data. I frequently
2973 use these three modules together to write complex database query
2974 apps in under 50 lines.
2976 =head1 HOW TO CONTRIBUTE
2978 Contributions are always welcome, in all usable forms (we especially
2979 welcome documentation improvements). The delivery methods include git-
2980 or unified-diff formatted patches, GitHub pull requests, or plain bug
2981 reports either via RT or the Mailing list. Contributors are generally
2982 granted full access to the official repository after their first several
2983 patches pass successful review.
2985 This project is maintained in a git repository. The code and related tools are
2986 accessible at the following locations:
2990 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2992 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2994 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2996 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3002 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3003 Great care has been taken to preserve the I<published> behavior
3004 documented in previous versions in the 1.* family; however,
3005 some features that were previously undocumented, or behaved
3006 differently from the documentation, had to be changed in order
3007 to clarify the semantics. Hence, client code that was relying
3008 on some dark areas of C<SQL::Abstract> v1.*
3009 B<might behave differently> in v1.50.
3011 The main changes are:
3017 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3021 support for the { operator => \"..." } construct (to embed literal SQL)
3025 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3029 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3033 defensive programming: check arguments
3037 fixed bug with global logic, which was previously implemented
3038 through global variables yielding side-effects. Prior versions would
3039 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3040 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3041 Now this is interpreted
3042 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3047 fixed semantics of _bindtype on array args
3051 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3052 we just avoid shifting arrays within that tree.
3056 dropped the C<_modlogic> function
3060 =head1 ACKNOWLEDGEMENTS
3062 There are a number of individuals that have really helped out with
3063 this module. Unfortunately, most of them submitted bugs via CPAN
3064 so I have no idea who they are! But the people I do know are:
3066 Ash Berlin (order_by hash term support)
3067 Matt Trout (DBIx::Class support)
3068 Mark Stosberg (benchmarking)
3069 Chas Owens (initial "IN" operator support)
3070 Philip Collins (per-field SQL functions)
3071 Eric Kolve (hashref "AND" support)
3072 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3073 Dan Kubb (support for "quote_char" and "name_sep")
3074 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3075 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3076 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3077 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3078 Oliver Charles (support for "RETURNING" after "INSERT")
3084 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3088 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3090 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3092 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3093 While not an official support venue, C<DBIx::Class> makes heavy use of
3094 C<SQL::Abstract>, and as such list members there are very familiar with
3095 how to create queries.
3099 This module is free software; you may copy this under the same
3100 terms as perl itself (either the GNU General Public License or
3101 the Artistic License)