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 return '' unless length($sql);
1135 my $final_sql = $self->_sqlcase(' order by ').$sql;
1137 return wantarray ? ($final_sql, @bind) : $final_sql;
1140 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1142 sub _order_by_chunks {
1143 my ($self, $arg) = @_;
1145 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1147 return $self->_chunkify_order_by($expanded);
1150 sub _chunkify_order_by {
1151 my ($self, $expanded) = @_;
1153 return grep length, $self->_render_expr($expanded)
1154 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1157 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1158 if ($op->[0] eq ',') {
1159 return map $self->_chunkify_order_by($_), @{$op}[1..$#$op];
1162 return [ $self->_render_expr($_) ];
1166 #======================================================================
1167 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1168 #======================================================================
1173 ($self->_render_expr(
1174 $self->_expand_maybe_list_expr($from, undef, -ident)
1179 #======================================================================
1181 #======================================================================
1183 sub _expand_maybe_list_expr {
1184 my ($self, $expr, $logic, $default) = @_;
1186 if (ref($expr) eq 'ARRAY') {
1188 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1195 return $self->_expand_expr($e, $logic, $default);
1198 # highly optimized, as it's called way too often
1200 # my ($self, $label) = @_;
1202 return '' unless defined $_[1];
1203 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1204 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1206 unless ($_[0]->{quote_char}) {
1207 if (ref($_[1]) eq 'ARRAY') {
1208 return join($_[0]->{name_sep}||'.', @{$_[1]});
1210 $_[0]->_assert_pass_injection_guard($_[1]);
1215 my $qref = ref $_[0]->{quote_char};
1217 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1218 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1219 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1221 my $esc = $_[0]->{escape_char} || $r;
1223 # parts containing * are naturally unquoted
1225 $_[0]->{name_sep}||'',
1229 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1231 (ref($_[1]) eq 'ARRAY'
1235 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1243 # Conversion, if applicable
1245 #my ($self, $arg) = @_;
1246 if ($_[0]->{convert_where}) {
1247 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1254 #my ($self, $col, @vals) = @_;
1255 # called often - tighten code
1256 return $_[0]->{bindtype} eq 'columns'
1257 ? map {[$_[1], $_]} @_[2 .. $#_]
1262 # Dies if any element of @bind is not in [colname => value] format
1263 # if bindtype is 'columns'.
1264 sub _assert_bindval_matches_bindtype {
1265 # my ($self, @bind) = @_;
1267 if ($self->{bindtype} eq 'columns') {
1269 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1270 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1276 sub _join_sql_clauses {
1277 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1279 if (@$clauses_aref > 1) {
1280 my $join = " " . $self->_sqlcase($logic) . " ";
1281 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1282 return ($sql, @$bind_aref);
1284 elsif (@$clauses_aref) {
1285 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1288 return (); # if no SQL, ignore @$bind_aref
1293 # Fix SQL case, if so requested
1295 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1296 # don't touch the argument ... crooked logic, but let's not change it!
1297 return $_[0]->{case} ? $_[1] : uc($_[1]);
1301 #======================================================================
1302 # DISPATCHING FROM REFKIND
1303 #======================================================================
1306 my ($self, $data) = @_;
1308 return 'UNDEF' unless defined $data;
1310 # blessed objects are treated like scalars
1311 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1313 return 'SCALAR' unless $ref;
1316 while ($ref eq 'REF') {
1318 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1322 return ($ref||'SCALAR') . ('REF' x $n_steps);
1326 my ($self, $data) = @_;
1327 my @try = ($self->_refkind($data));
1328 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1329 push @try, 'FALLBACK';
1333 sub _METHOD_FOR_refkind {
1334 my ($self, $meth_prefix, $data) = @_;
1337 for (@{$self->_try_refkind($data)}) {
1338 $method = $self->can($meth_prefix."_".$_)
1342 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1346 sub _SWITCH_refkind {
1347 my ($self, $data, $dispatch_table) = @_;
1350 for (@{$self->_try_refkind($data)}) {
1351 $coderef = $dispatch_table->{$_}
1355 puke "no dispatch entry for ".$self->_refkind($data)
1364 #======================================================================
1365 # VALUES, GENERATE, AUTOLOAD
1366 #======================================================================
1368 # LDNOTE: original code from nwiger, didn't touch code in that section
1369 # I feel the AUTOLOAD stuff should not be the default, it should
1370 # only be activated on explicit demand by user.
1374 my $data = shift || return;
1375 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1376 unless ref $data eq 'HASH';
1379 foreach my $k (sort keys %$data) {
1380 my $v = $data->{$k};
1381 $self->_SWITCH_refkind($v, {
1383 if ($self->{array_datatypes}) { # array datatype
1384 push @all_bind, $self->_bindtype($k, $v);
1386 else { # literal SQL with bind
1387 my ($sql, @bind) = @$v;
1388 $self->_assert_bindval_matches_bindtype(@bind);
1389 push @all_bind, @bind;
1392 ARRAYREFREF => sub { # literal SQL with bind
1393 my ($sql, @bind) = @${$v};
1394 $self->_assert_bindval_matches_bindtype(@bind);
1395 push @all_bind, @bind;
1397 SCALARREF => sub { # literal SQL without bind
1399 SCALAR_or_UNDEF => sub {
1400 push @all_bind, $self->_bindtype($k, $v);
1411 my(@sql, @sqlq, @sqlv);
1415 if ($ref eq 'HASH') {
1416 for my $k (sort keys %$_) {
1419 my $label = $self->_quote($k);
1420 if ($r eq 'ARRAY') {
1421 # literal SQL with bind
1422 my ($sql, @bind) = @$v;
1423 $self->_assert_bindval_matches_bindtype(@bind);
1424 push @sqlq, "$label = $sql";
1426 } elsif ($r eq 'SCALAR') {
1427 # literal SQL without bind
1428 push @sqlq, "$label = $$v";
1430 push @sqlq, "$label = ?";
1431 push @sqlv, $self->_bindtype($k, $v);
1434 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1435 } elsif ($ref eq 'ARRAY') {
1436 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1439 if ($r eq 'ARRAY') { # literal SQL with bind
1440 my ($sql, @bind) = @$v;
1441 $self->_assert_bindval_matches_bindtype(@bind);
1444 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1445 # embedded literal SQL
1452 push @sql, '(' . join(', ', @sqlq) . ')';
1453 } elsif ($ref eq 'SCALAR') {
1457 # strings get case twiddled
1458 push @sql, $self->_sqlcase($_);
1462 my $sql = join ' ', @sql;
1464 # this is pretty tricky
1465 # if ask for an array, return ($stmt, @bind)
1466 # otherwise, s/?/shift @sqlv/ to put it inline
1468 return ($sql, @sqlv);
1470 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1471 ref $d ? $d->[1] : $d/e;
1480 # This allows us to check for a local, then _form, attr
1482 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1483 return $self->generate($name, @_);
1494 SQL::Abstract - Generate SQL from Perl data structures
1500 my $sql = SQL::Abstract->new;
1502 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1504 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1506 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1508 my($stmt, @bind) = $sql->delete($table, \%where);
1510 # Then, use these in your DBI statements
1511 my $sth = $dbh->prepare($stmt);
1512 $sth->execute(@bind);
1514 # Just generate the WHERE clause
1515 my($stmt, @bind) = $sql->where(\%where, $order);
1517 # Return values in the same order, for hashed queries
1518 # See PERFORMANCE section for more details
1519 my @bind = $sql->values(\%fieldvals);
1523 This module was inspired by the excellent L<DBIx::Abstract>.
1524 However, in using that module I found that what I really wanted
1525 to do was generate SQL, but still retain complete control over my
1526 statement handles and use the DBI interface. So, I set out to
1527 create an abstract SQL generation module.
1529 While based on the concepts used by L<DBIx::Abstract>, there are
1530 several important differences, especially when it comes to WHERE
1531 clauses. I have modified the concepts used to make the SQL easier
1532 to generate from Perl data structures and, IMO, more intuitive.
1533 The underlying idea is for this module to do what you mean, based
1534 on the data structures you provide it. The big advantage is that
1535 you don't have to modify your code every time your data changes,
1536 as this module figures it out.
1538 To begin with, an SQL INSERT is as easy as just specifying a hash
1539 of C<key=value> pairs:
1542 name => 'Jimbo Bobson',
1543 phone => '123-456-7890',
1544 address => '42 Sister Lane',
1545 city => 'St. Louis',
1546 state => 'Louisiana',
1549 The SQL can then be generated with this:
1551 my($stmt, @bind) = $sql->insert('people', \%data);
1553 Which would give you something like this:
1555 $stmt = "INSERT INTO people
1556 (address, city, name, phone, state)
1557 VALUES (?, ?, ?, ?, ?)";
1558 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1559 '123-456-7890', 'Louisiana');
1561 These are then used directly in your DBI code:
1563 my $sth = $dbh->prepare($stmt);
1564 $sth->execute(@bind);
1566 =head2 Inserting and Updating Arrays
1568 If your database has array types (like for example Postgres),
1569 activate the special option C<< array_datatypes => 1 >>
1570 when creating the C<SQL::Abstract> object.
1571 Then you may use an arrayref to insert and update database array types:
1573 my $sql = SQL::Abstract->new(array_datatypes => 1);
1575 planets => [qw/Mercury Venus Earth Mars/]
1578 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1582 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1584 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1587 =head2 Inserting and Updating SQL
1589 In order to apply SQL functions to elements of your C<%data> you may
1590 specify a reference to an arrayref for the given hash value. For example,
1591 if you need to execute the Oracle C<to_date> function on a value, you can
1592 say something like this:
1596 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1599 The first value in the array is the actual SQL. Any other values are
1600 optional and would be included in the bind values array. This gives
1603 my($stmt, @bind) = $sql->insert('people', \%data);
1605 $stmt = "INSERT INTO people (name, date_entered)
1606 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1607 @bind = ('Bill', '03/02/2003');
1609 An UPDATE is just as easy, all you change is the name of the function:
1611 my($stmt, @bind) = $sql->update('people', \%data);
1613 Notice that your C<%data> isn't touched; the module will generate
1614 the appropriately quirky SQL for you automatically. Usually you'll
1615 want to specify a WHERE clause for your UPDATE, though, which is
1616 where handling C<%where> hashes comes in handy...
1618 =head2 Complex where statements
1620 This module can generate pretty complicated WHERE statements
1621 easily. For example, simple C<key=value> pairs are taken to mean
1622 equality, and if you want to see if a field is within a set
1623 of values, you can use an arrayref. Let's say we wanted to
1624 SELECT some data based on this criteria:
1627 requestor => 'inna',
1628 worker => ['nwiger', 'rcwe', 'sfz'],
1629 status => { '!=', 'completed' }
1632 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1634 The above would give you something like this:
1636 $stmt = "SELECT * FROM tickets WHERE
1637 ( requestor = ? ) AND ( status != ? )
1638 AND ( worker = ? OR worker = ? OR worker = ? )";
1639 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1641 Which you could then use in DBI code like so:
1643 my $sth = $dbh->prepare($stmt);
1644 $sth->execute(@bind);
1650 The methods are simple. There's one for every major SQL operation,
1651 and a constructor you use first. The arguments are specified in a
1652 similar order for each method (table, then fields, then a where
1653 clause) to try and simplify things.
1655 =head2 new(option => 'value')
1657 The C<new()> function takes a list of options and values, and returns
1658 a new B<SQL::Abstract> object which can then be used to generate SQL
1659 through the methods below. The options accepted are:
1665 If set to 'lower', then SQL will be generated in all lowercase. By
1666 default SQL is generated in "textbook" case meaning something like:
1668 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1670 Any setting other than 'lower' is ignored.
1674 This determines what the default comparison operator is. By default
1675 it is C<=>, meaning that a hash like this:
1677 %where = (name => 'nwiger', email => 'nate@wiger.org');
1679 Will generate SQL like this:
1681 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1683 However, you may want loose comparisons by default, so if you set
1684 C<cmp> to C<like> you would get SQL such as:
1686 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1688 You can also override the comparison on an individual basis - see
1689 the huge section on L</"WHERE CLAUSES"> at the bottom.
1691 =item sqltrue, sqlfalse
1693 Expressions for inserting boolean values within SQL statements.
1694 By default these are C<1=1> and C<1=0>. They are used
1695 by the special operators C<-in> and C<-not_in> for generating
1696 correct SQL even when the argument is an empty array (see below).
1700 This determines the default logical operator for multiple WHERE
1701 statements in arrays or hashes. If absent, the default logic is "or"
1702 for arrays, and "and" for hashes. This means that a WHERE
1706 event_date => {'>=', '2/13/99'},
1707 event_date => {'<=', '4/24/03'},
1710 will generate SQL like this:
1712 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1714 This is probably not what you want given this query, though (look
1715 at the dates). To change the "OR" to an "AND", simply specify:
1717 my $sql = SQL::Abstract->new(logic => 'and');
1719 Which will change the above C<WHERE> to:
1721 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1723 The logic can also be changed locally by inserting
1724 a modifier in front of an arrayref:
1726 @where = (-and => [event_date => {'>=', '2/13/99'},
1727 event_date => {'<=', '4/24/03'} ]);
1729 See the L</"WHERE CLAUSES"> section for explanations.
1733 This will automatically convert comparisons using the specified SQL
1734 function for both column and value. This is mostly used with an argument
1735 of C<upper> or C<lower>, so that the SQL will have the effect of
1736 case-insensitive "searches". For example, this:
1738 $sql = SQL::Abstract->new(convert => 'upper');
1739 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1741 Will turn out the following SQL:
1743 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1745 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1746 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1747 not validate this option; it will just pass through what you specify verbatim).
1751 This is a kludge because many databases suck. For example, you can't
1752 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1753 Instead, you have to use C<bind_param()>:
1755 $sth->bind_param(1, 'reg data');
1756 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1758 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1759 which loses track of which field each slot refers to. Fear not.
1761 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1762 Currently, you can specify either C<normal> (default) or C<columns>. If you
1763 specify C<columns>, you will get an array that looks like this:
1765 my $sql = SQL::Abstract->new(bindtype => 'columns');
1766 my($stmt, @bind) = $sql->insert(...);
1769 [ 'column1', 'value1' ],
1770 [ 'column2', 'value2' ],
1771 [ 'column3', 'value3' ],
1774 You can then iterate through this manually, using DBI's C<bind_param()>.
1776 $sth->prepare($stmt);
1779 my($col, $data) = @$_;
1780 if ($col eq 'details' || $col eq 'comments') {
1781 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1782 } elsif ($col eq 'image') {
1783 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1785 $sth->bind_param($i, $data);
1789 $sth->execute; # execute without @bind now
1791 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1792 Basically, the advantage is still that you don't have to care which fields
1793 are or are not included. You could wrap that above C<for> loop in a simple
1794 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1795 get a layer of abstraction over manual SQL specification.
1797 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1798 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1799 will expect the bind values in this format.
1803 This is the character that a table or column name will be quoted
1804 with. By default this is an empty string, but you could set it to
1805 the character C<`>, to generate SQL like this:
1807 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1809 Alternatively, you can supply an array ref of two items, the first being the left
1810 hand quote character, and the second the right hand quote character. For
1811 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1812 that generates SQL like this:
1814 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1816 Quoting is useful if you have tables or columns names that are reserved
1817 words in your database's SQL dialect.
1821 This is the character that will be used to escape L</quote_char>s appearing
1822 in an identifier before it has been quoted.
1824 The parameter default in case of a single L</quote_char> character is the quote
1827 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1828 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1829 of the B<opening (left)> L</quote_char> within the identifier are currently left
1830 untouched. The default for opening-closing-style quotes may change in future
1831 versions, thus you are B<strongly encouraged> to specify the escape character
1836 This is the character that separates a table and column name. It is
1837 necessary to specify this when the C<quote_char> option is selected,
1838 so that tables and column names can be individually quoted like this:
1840 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1842 =item injection_guard
1844 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1845 column name specified in a query structure. This is a safety mechanism to avoid
1846 injection attacks when mishandling user input e.g.:
1848 my %condition_as_column_value_pairs = get_values_from_user();
1849 $sqla->select( ... , \%condition_as_column_value_pairs );
1851 If the expression matches an exception is thrown. Note that literal SQL
1852 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1854 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1856 =item array_datatypes
1858 When this option is true, arrayrefs in INSERT or UPDATE are
1859 interpreted as array datatypes and are passed directly
1861 When this option is false, arrayrefs are interpreted
1862 as literal SQL, just like refs to arrayrefs
1863 (but this behavior is for backwards compatibility; when writing
1864 new queries, use the "reference to arrayref" syntax
1870 Takes a reference to a list of "special operators"
1871 to extend the syntax understood by L<SQL::Abstract>.
1872 See section L</"SPECIAL OPERATORS"> for details.
1876 Takes a reference to a list of "unary operators"
1877 to extend the syntax understood by L<SQL::Abstract>.
1878 See section L</"UNARY OPERATORS"> for details.
1884 =head2 insert($table, \@values || \%fieldvals, \%options)
1886 This is the simplest function. You simply give it a table name
1887 and either an arrayref of values or hashref of field/value pairs.
1888 It returns an SQL INSERT statement and a list of bind values.
1889 See the sections on L</"Inserting and Updating Arrays"> and
1890 L</"Inserting and Updating SQL"> for information on how to insert
1891 with those data types.
1893 The optional C<\%options> hash reference may contain additional
1894 options to generate the insert SQL. Currently supported options
1901 Takes either a scalar of raw SQL fields, or an array reference of
1902 field names, and adds on an SQL C<RETURNING> statement at the end.
1903 This allows you to return data generated by the insert statement
1904 (such as row IDs) without performing another C<SELECT> statement.
1905 Note, however, this is not part of the SQL standard and may not
1906 be supported by all database engines.
1910 =head2 update($table, \%fieldvals, \%where, \%options)
1912 This takes a table, hashref of field/value pairs, and an optional
1913 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1915 See the sections on L</"Inserting and Updating Arrays"> and
1916 L</"Inserting and Updating SQL"> for information on how to insert
1917 with those data types.
1919 The optional C<\%options> hash reference may contain additional
1920 options to generate the update SQL. Currently supported options
1927 See the C<returning> option to
1928 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1932 =head2 select($source, $fields, $where, $order)
1934 This returns a SQL SELECT statement and associated list of bind values, as
1935 specified by the arguments:
1941 Specification of the 'FROM' part of the statement.
1942 The argument can be either a plain scalar (interpreted as a table
1943 name, will be quoted), or an arrayref (interpreted as a list
1944 of table names, joined by commas, quoted), or a scalarref
1945 (literal SQL, not quoted).
1949 Specification of the list of fields to retrieve from
1951 The argument can be either an arrayref (interpreted as a list
1952 of field names, will be joined by commas and quoted), or a
1953 plain scalar (literal SQL, not quoted).
1954 Please observe that this API is not as flexible as that of
1955 the first argument C<$source>, for backwards compatibility reasons.
1959 Optional argument to specify the WHERE part of the query.
1960 The argument is most often a hashref, but can also be
1961 an arrayref or plain scalar --
1962 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1966 Optional argument to specify the ORDER BY part of the query.
1967 The argument can be a scalar, a hashref or an arrayref
1968 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1974 =head2 delete($table, \%where, \%options)
1976 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1977 It returns an SQL DELETE statement and list of bind values.
1979 The optional C<\%options> hash reference may contain additional
1980 options to generate the delete SQL. Currently supported options
1987 See the C<returning> option to
1988 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1992 =head2 where(\%where, $order)
1994 This is used to generate just the WHERE clause. For example,
1995 if you have an arbitrary data structure and know what the
1996 rest of your SQL is going to look like, but want an easy way
1997 to produce a WHERE clause, use this. It returns an SQL WHERE
1998 clause and list of bind values.
2001 =head2 values(\%data)
2003 This just returns the values from the hash C<%data>, in the same
2004 order that would be returned from any of the other above queries.
2005 Using this allows you to markedly speed up your queries if you
2006 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2008 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2010 Warning: This is an experimental method and subject to change.
2012 This returns arbitrarily generated SQL. It's a really basic shortcut.
2013 It will return two different things, depending on return context:
2015 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2016 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2018 These would return the following:
2020 # First calling form
2021 $stmt = "CREATE TABLE test (?, ?)";
2022 @bind = (field1, field2);
2024 # Second calling form
2025 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2027 Depending on what you're trying to do, it's up to you to choose the correct
2028 format. In this example, the second form is what you would want.
2032 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2036 ALTER SESSION SET nls_date_format = 'MM/YY'
2038 You get the idea. Strings get their case twiddled, but everything
2039 else remains verbatim.
2041 =head1 EXPORTABLE FUNCTIONS
2043 =head2 is_plain_value
2045 Determines if the supplied argument is a plain value as understood by this
2050 =item * The value is C<undef>
2052 =item * The value is a non-reference
2054 =item * The value is an object with stringification overloading
2056 =item * The value is of the form C<< { -value => $anything } >>
2060 On failure returns C<undef>, on success returns a B<scalar> reference
2061 to the original supplied argument.
2067 The stringification overloading detection is rather advanced: it takes
2068 into consideration not only the presence of a C<""> overload, but if that
2069 fails also checks for enabled
2070 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2071 on either C<0+> or C<bool>.
2073 Unfortunately testing in the field indicates that this
2074 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2075 but only when very large numbers of stringifying objects are involved.
2076 At the time of writing ( Sep 2014 ) there is no clear explanation of
2077 the direct cause, nor is there a manageably small test case that reliably
2078 reproduces the problem.
2080 If you encounter any of the following exceptions in B<random places within
2081 your application stack> - this module may be to blame:
2083 Operation "ne": no method found,
2084 left argument in overloaded package <something>,
2085 right argument in overloaded package <something>
2089 Stub found while resolving method "???" overloading """" in package <something>
2091 If you fall victim to the above - please attempt to reduce the problem
2092 to something that could be sent to the L<SQL::Abstract developers
2093 |DBIx::Class/GETTING HELP/SUPPORT>
2094 (either publicly or privately). As a workaround in the meantime you can
2095 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2096 value, which will most likely eliminate your problem (at the expense of
2097 not being able to properly detect exotic forms of stringification).
2099 This notice and environment variable will be removed in a future version,
2100 as soon as the underlying problem is found and a reliable workaround is
2105 =head2 is_literal_value
2107 Determines if the supplied argument is a literal value as understood by this
2112 =item * C<\$sql_string>
2114 =item * C<\[ $sql_string, @bind_values ]>
2118 On failure returns C<undef>, on success returns an B<array> reference
2119 containing the unpacked version of the supplied literal SQL and bind values.
2121 =head1 WHERE CLAUSES
2125 This module uses a variation on the idea from L<DBIx::Abstract>. It
2126 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2127 module is that things in arrays are OR'ed, and things in hashes
2130 The easiest way to explain is to show lots of examples. After
2131 each C<%where> hash shown, it is assumed you used:
2133 my($stmt, @bind) = $sql->where(\%where);
2135 However, note that the C<%where> hash can be used directly in any
2136 of the other functions as well, as described above.
2138 =head2 Key-value pairs
2140 So, let's get started. To begin, a simple hash:
2144 status => 'completed'
2147 Is converted to SQL C<key = val> statements:
2149 $stmt = "WHERE user = ? AND status = ?";
2150 @bind = ('nwiger', 'completed');
2152 One common thing I end up doing is having a list of values that
2153 a field can be in. To do this, simply specify a list inside of
2158 status => ['assigned', 'in-progress', 'pending'];
2161 This simple code will create the following:
2163 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2164 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2166 A field associated to an empty arrayref will be considered a
2167 logical false and will generate 0=1.
2169 =head2 Tests for NULL values
2171 If the value part is C<undef> then this is converted to SQL <IS NULL>
2180 $stmt = "WHERE user = ? AND status IS NULL";
2183 To test if a column IS NOT NULL:
2187 status => { '!=', undef },
2190 =head2 Specific comparison operators
2192 If you want to specify a different type of operator for your comparison,
2193 you can use a hashref for a given column:
2197 status => { '!=', 'completed' }
2200 Which would generate:
2202 $stmt = "WHERE user = ? AND status != ?";
2203 @bind = ('nwiger', 'completed');
2205 To test against multiple values, just enclose the values in an arrayref:
2207 status => { '=', ['assigned', 'in-progress', 'pending'] };
2209 Which would give you:
2211 "WHERE status = ? OR status = ? OR status = ?"
2214 The hashref can also contain multiple pairs, in which case it is expanded
2215 into an C<AND> of its elements:
2219 status => { '!=', 'completed', -not_like => 'pending%' }
2222 # Or more dynamically, like from a form
2223 $where{user} = 'nwiger';
2224 $where{status}{'!='} = 'completed';
2225 $where{status}{'-not_like'} = 'pending%';
2227 # Both generate this
2228 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2229 @bind = ('nwiger', 'completed', 'pending%');
2232 To get an OR instead, you can combine it with the arrayref idea:
2236 priority => [ { '=', 2 }, { '>', 5 } ]
2239 Which would generate:
2241 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2242 @bind = ('2', '5', 'nwiger');
2244 If you want to include literal SQL (with or without bind values), just use a
2245 scalar reference or reference to an arrayref as the value:
2248 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2249 date_expires => { '<' => \"now()" }
2252 Which would generate:
2254 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2255 @bind = ('11/26/2008');
2258 =head2 Logic and nesting operators
2260 In the example above,
2261 there is a subtle trap if you want to say something like
2262 this (notice the C<AND>):
2264 WHERE priority != ? AND priority != ?
2266 Because, in Perl you I<can't> do this:
2268 priority => { '!=' => 2, '!=' => 1 }
2270 As the second C<!=> key will obliterate the first. The solution
2271 is to use the special C<-modifier> form inside an arrayref:
2273 priority => [ -and => {'!=', 2},
2277 Normally, these would be joined by C<OR>, but the modifier tells it
2278 to use C<AND> instead. (Hint: You can use this in conjunction with the
2279 C<logic> option to C<new()> in order to change the way your queries
2280 work by default.) B<Important:> Note that the C<-modifier> goes
2281 B<INSIDE> the arrayref, as an extra first element. This will
2282 B<NOT> do what you think it might:
2284 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2286 Here is a quick list of equivalencies, since there is some overlap:
2289 status => {'!=', 'completed', 'not like', 'pending%' }
2290 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2293 status => {'=', ['assigned', 'in-progress']}
2294 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2295 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2299 =head2 Special operators: IN, BETWEEN, etc.
2301 You can also use the hashref format to compare a list of fields using the
2302 C<IN> comparison operator, by specifying the list as an arrayref:
2305 status => 'completed',
2306 reportid => { -in => [567, 2335, 2] }
2309 Which would generate:
2311 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2312 @bind = ('completed', '567', '2335', '2');
2314 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2317 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2318 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2319 'sqltrue' (by default: C<1=1>).
2321 In addition to the array you can supply a chunk of literal sql or
2322 literal sql with bind:
2325 customer => { -in => \[
2326 'SELECT cust_id FROM cust WHERE balance > ?',
2329 status => { -in => \'SELECT status_codes FROM states' },
2335 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2336 AND status IN ( SELECT status_codes FROM states )
2340 Finally, if the argument to C<-in> is not a reference, it will be
2341 treated as a single-element array.
2343 Another pair of operators is C<-between> and C<-not_between>,
2344 used with an arrayref of two values:
2348 completion_date => {
2349 -not_between => ['2002-10-01', '2003-02-06']
2355 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2357 Just like with C<-in> all plausible combinations of literal SQL
2361 start0 => { -between => [ 1, 2 ] },
2362 start1 => { -between => \["? AND ?", 1, 2] },
2363 start2 => { -between => \"lower(x) AND upper(y)" },
2364 start3 => { -between => [
2366 \["upper(?)", 'stuff' ],
2373 ( start0 BETWEEN ? AND ? )
2374 AND ( start1 BETWEEN ? AND ? )
2375 AND ( start2 BETWEEN lower(x) AND upper(y) )
2376 AND ( start3 BETWEEN lower(x) AND upper(?) )
2378 @bind = (1, 2, 1, 2, 'stuff');
2381 These are the two builtin "special operators"; but the
2382 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2384 =head2 Unary operators: bool
2386 If you wish to test against boolean columns or functions within your
2387 database you can use the C<-bool> and C<-not_bool> operators. For
2388 example to test the column C<is_user> being true and the column
2389 C<is_enabled> being false you would use:-
2393 -not_bool => 'is_enabled',
2398 WHERE is_user AND NOT is_enabled
2400 If a more complex combination is required, testing more conditions,
2401 then you should use the and/or operators:-
2406 -not_bool => { two=> { -rlike => 'bar' } },
2407 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2418 (NOT ( three = ? OR three > ? ))
2421 =head2 Nested conditions, -and/-or prefixes
2423 So far, we've seen how multiple conditions are joined with a top-level
2424 C<AND>. We can change this by putting the different conditions we want in
2425 hashes and then putting those hashes in an array. For example:
2430 status => { -like => ['pending%', 'dispatched'] },
2434 status => 'unassigned',
2438 This data structure would create the following:
2440 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2441 OR ( user = ? AND status = ? ) )";
2442 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2445 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2446 to change the logic inside:
2452 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2453 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2460 $stmt = "WHERE ( user = ?
2461 AND ( ( workhrs > ? AND geo = ? )
2462 OR ( workhrs < ? OR geo = ? ) ) )";
2463 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2465 =head3 Algebraic inconsistency, for historical reasons
2467 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2468 operator goes C<outside> of the nested structure; whereas when connecting
2469 several constraints on one column, the C<-and> operator goes
2470 C<inside> the arrayref. Here is an example combining both features:
2473 -and => [a => 1, b => 2],
2474 -or => [c => 3, d => 4],
2475 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2480 WHERE ( ( ( a = ? AND b = ? )
2481 OR ( c = ? OR d = ? )
2482 OR ( e LIKE ? AND e LIKE ? ) ) )
2484 This difference in syntax is unfortunate but must be preserved for
2485 historical reasons. So be careful: the two examples below would
2486 seem algebraically equivalent, but they are not
2489 { -like => 'foo%' },
2490 { -like => '%bar' },
2492 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2495 { col => { -like => 'foo%' } },
2496 { col => { -like => '%bar' } },
2498 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2501 =head2 Literal SQL and value type operators
2503 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2504 side" is a column name and the "right side" is a value (normally rendered as
2505 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2506 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2507 alter this behavior. There are several ways of doing so.
2511 This is a virtual operator that signals the string to its right side is an
2512 identifier (a column name) and not a value. For example to compare two
2513 columns you would write:
2516 priority => { '<', 2 },
2517 requestor => { -ident => 'submitter' },
2522 $stmt = "WHERE priority < ? AND requestor = submitter";
2525 If you are maintaining legacy code you may see a different construct as
2526 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2531 This is a virtual operator that signals that the construct to its right side
2532 is a value to be passed to DBI. This is for example necessary when you want
2533 to write a where clause against an array (for RDBMS that support such
2534 datatypes). For example:
2537 array => { -value => [1, 2, 3] }
2542 $stmt = 'WHERE array = ?';
2543 @bind = ([1, 2, 3]);
2545 Note that if you were to simply say:
2551 the result would probably not be what you wanted:
2553 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2558 Finally, sometimes only literal SQL will do. To include a random snippet
2559 of SQL verbatim, you specify it as a scalar reference. Consider this only
2560 as a last resort. Usually there is a better way. For example:
2563 priority => { '<', 2 },
2564 requestor => { -in => \'(SELECT name FROM hitmen)' },
2569 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2572 Note that in this example, you only get one bind parameter back, since
2573 the verbatim SQL is passed as part of the statement.
2577 Never use untrusted input as a literal SQL argument - this is a massive
2578 security risk (there is no way to check literal snippets for SQL
2579 injections and other nastyness). If you need to deal with untrusted input
2580 use literal SQL with placeholders as described next.
2582 =head3 Literal SQL with placeholders and bind values (subqueries)
2584 If the literal SQL to be inserted has placeholders and bind values,
2585 use a reference to an arrayref (yes this is a double reference --
2586 not so common, but perfectly legal Perl). For example, to find a date
2587 in Postgres you can use something like this:
2590 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2595 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2598 Note that you must pass the bind values in the same format as they are returned
2599 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2600 to C<columns>, you must provide the bind values in the
2601 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2602 scalar value; most commonly the column name, but you can use any scalar value
2603 (including references and blessed references), L<SQL::Abstract> will simply
2604 pass it through intact. So if C<bindtype> is set to C<columns> the above
2605 example will look like:
2608 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2611 Literal SQL is especially useful for nesting parenthesized clauses in the
2612 main SQL query. Here is a first example:
2614 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2618 bar => \["IN ($sub_stmt)" => @sub_bind],
2623 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2624 WHERE c2 < ? AND c3 LIKE ?))";
2625 @bind = (1234, 100, "foo%");
2627 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2628 are expressed in the same way. Of course the C<$sub_stmt> and
2629 its associated bind values can be generated through a former call
2632 my ($sub_stmt, @sub_bind)
2633 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2634 c3 => {-like => "foo%"}});
2637 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2640 In the examples above, the subquery was used as an operator on a column;
2641 but the same principle also applies for a clause within the main C<%where>
2642 hash, like an EXISTS subquery:
2644 my ($sub_stmt, @sub_bind)
2645 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2646 my %where = ( -and => [
2648 \["EXISTS ($sub_stmt)" => @sub_bind],
2653 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2654 WHERE c1 = ? AND c2 > t0.c0))";
2658 Observe that the condition on C<c2> in the subquery refers to
2659 column C<t0.c0> of the main query: this is I<not> a bind
2660 value, so we have to express it through a scalar ref.
2661 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2662 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2663 what we wanted here.
2665 Finally, here is an example where a subquery is used
2666 for expressing unary negation:
2668 my ($sub_stmt, @sub_bind)
2669 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2670 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2672 lname => {like => '%son%'},
2673 \["NOT ($sub_stmt)" => @sub_bind],
2678 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2679 @bind = ('%son%', 10, 20)
2681 =head3 Deprecated usage of Literal SQL
2683 Below are some examples of archaic use of literal SQL. It is shown only as
2684 reference for those who deal with legacy code. Each example has a much
2685 better, cleaner and safer alternative that users should opt for in new code.
2691 my %where = ( requestor => \'IS NOT NULL' )
2693 $stmt = "WHERE requestor IS NOT NULL"
2695 This used to be the way of generating NULL comparisons, before the handling
2696 of C<undef> got formalized. For new code please use the superior syntax as
2697 described in L</Tests for NULL values>.
2701 my %where = ( requestor => \'= submitter' )
2703 $stmt = "WHERE requestor = submitter"
2705 This used to be the only way to compare columns. Use the superior L</-ident>
2706 method for all new code. For example an identifier declared in such a way
2707 will be properly quoted if L</quote_char> is properly set, while the legacy
2708 form will remain as supplied.
2712 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2714 $stmt = "WHERE completed > ? AND is_ready"
2715 @bind = ('2012-12-21')
2717 Using an empty string literal used to be the only way to express a boolean.
2718 For all new code please use the much more readable
2719 L<-bool|/Unary operators: bool> operator.
2725 These pages could go on for a while, since the nesting of the data
2726 structures this module can handle are pretty much unlimited (the
2727 module implements the C<WHERE> expansion as a recursive function
2728 internally). Your best bet is to "play around" with the module a
2729 little to see how the data structures behave, and choose the best
2730 format for your data based on that.
2732 And of course, all the values above will probably be replaced with
2733 variables gotten from forms or the command line. After all, if you
2734 knew everything ahead of time, you wouldn't have to worry about
2735 dynamically-generating SQL and could just hardwire it into your
2738 =head1 ORDER BY CLAUSES
2740 Some functions take an order by clause. This can either be a scalar (just a
2741 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2742 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2745 Given | Will Generate
2746 ---------------------------------------------------------------
2748 'colA' | ORDER BY colA
2750 [qw/colA colB/] | ORDER BY colA, colB
2752 {-asc => 'colA'} | ORDER BY colA ASC
2754 {-desc => 'colB'} | ORDER BY colB DESC
2756 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2758 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2760 \'colA DESC' | ORDER BY colA DESC
2762 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2763 | /* ...with $x bound to ? */
2766 { -asc => 'colA' }, | colA ASC,
2767 { -desc => [qw/colB/] }, | colB DESC,
2768 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2769 \'colE DESC', | colE DESC,
2770 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2771 ] | /* ...with $x bound to ? */
2772 ===============================================================
2776 =head1 SPECIAL OPERATORS
2778 my $sqlmaker = SQL::Abstract->new(special_ops => [
2782 my ($self, $field, $op, $arg) = @_;
2788 handler => 'method_name',
2792 A "special operator" is a SQL syntactic clause that can be
2793 applied to a field, instead of a usual binary operator.
2796 WHERE field IN (?, ?, ?)
2797 WHERE field BETWEEN ? AND ?
2798 WHERE MATCH(field) AGAINST (?, ?)
2800 Special operators IN and BETWEEN are fairly standard and therefore
2801 are builtin within C<SQL::Abstract> (as the overridable methods
2802 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2803 like the MATCH .. AGAINST example above which is specific to MySQL,
2804 you can write your own operator handlers - supply a C<special_ops>
2805 argument to the C<new> method. That argument takes an arrayref of
2806 operator definitions; each operator definition is a hashref with two
2813 the regular expression to match the operator
2817 Either a coderef or a plain scalar method name. In both cases
2818 the expected return is C<< ($sql, @bind) >>.
2820 When supplied with a method name, it is simply called on the
2821 L<SQL::Abstract> object as:
2823 $self->$method_name($field, $op, $arg)
2827 $field is the LHS of the operator
2828 $op is the part that matched the handler regex
2831 When supplied with a coderef, it is called as:
2833 $coderef->($self, $field, $op, $arg)
2838 For example, here is an implementation
2839 of the MATCH .. AGAINST syntax for MySQL
2841 my $sqlmaker = SQL::Abstract->new(special_ops => [
2843 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2844 {regex => qr/^match$/i,
2846 my ($self, $field, $op, $arg) = @_;
2847 $arg = [$arg] if not ref $arg;
2848 my $label = $self->_quote($field);
2849 my ($placeholder) = $self->_convert('?');
2850 my $placeholders = join ", ", (($placeholder) x @$arg);
2851 my $sql = $self->_sqlcase('match') . " ($label) "
2852 . $self->_sqlcase('against') . " ($placeholders) ";
2853 my @bind = $self->_bindtype($field, @$arg);
2854 return ($sql, @bind);
2861 =head1 UNARY OPERATORS
2863 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2867 my ($self, $op, $arg) = @_;
2873 handler => 'method_name',
2877 A "unary operator" is a SQL syntactic clause that can be
2878 applied to a field - the operator goes before the field
2880 You can write your own operator handlers - supply a C<unary_ops>
2881 argument to the C<new> method. That argument takes an arrayref of
2882 operator definitions; each operator definition is a hashref with two
2889 the regular expression to match the operator
2893 Either a coderef or a plain scalar method name. In both cases
2894 the expected return is C<< $sql >>.
2896 When supplied with a method name, it is simply called on the
2897 L<SQL::Abstract> object as:
2899 $self->$method_name($op, $arg)
2903 $op is the part that matched the handler regex
2904 $arg is the RHS or argument of the operator
2906 When supplied with a coderef, it is called as:
2908 $coderef->($self, $op, $arg)
2916 Thanks to some benchmarking by Mark Stosberg, it turns out that
2917 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2918 I must admit this wasn't an intentional design issue, but it's a
2919 byproduct of the fact that you get to control your C<DBI> handles
2922 To maximize performance, use a code snippet like the following:
2924 # prepare a statement handle using the first row
2925 # and then reuse it for the rest of the rows
2927 for my $href (@array_of_hashrefs) {
2928 $stmt ||= $sql->insert('table', $href);
2929 $sth ||= $dbh->prepare($stmt);
2930 $sth->execute($sql->values($href));
2933 The reason this works is because the keys in your C<$href> are sorted
2934 internally by B<SQL::Abstract>. Thus, as long as your data retains
2935 the same structure, you only have to generate the SQL the first time
2936 around. On subsequent queries, simply use the C<values> function provided
2937 by this module to return your values in the correct order.
2939 However this depends on the values having the same type - if, for
2940 example, the values of a where clause may either have values
2941 (resulting in sql of the form C<column = ?> with a single bind
2942 value), or alternatively the values might be C<undef> (resulting in
2943 sql of the form C<column IS NULL> with no bind value) then the
2944 caching technique suggested will not work.
2948 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2949 really like this part (I do, at least). Building up a complex query
2950 can be as simple as the following:
2957 use CGI::FormBuilder;
2960 my $form = CGI::FormBuilder->new(...);
2961 my $sql = SQL::Abstract->new;
2963 if ($form->submitted) {
2964 my $field = $form->field;
2965 my $id = delete $field->{id};
2966 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2969 Of course, you would still have to connect using C<DBI> to run the
2970 query, but the point is that if you make your form look like your
2971 table, the actual query script can be extremely simplistic.
2973 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2974 a fast interface to returning and formatting data. I frequently
2975 use these three modules together to write complex database query
2976 apps in under 50 lines.
2978 =head1 HOW TO CONTRIBUTE
2980 Contributions are always welcome, in all usable forms (we especially
2981 welcome documentation improvements). The delivery methods include git-
2982 or unified-diff formatted patches, GitHub pull requests, or plain bug
2983 reports either via RT or the Mailing list. Contributors are generally
2984 granted full access to the official repository after their first several
2985 patches pass successful review.
2987 This project is maintained in a git repository. The code and related tools are
2988 accessible at the following locations:
2992 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2994 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2996 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2998 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3004 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3005 Great care has been taken to preserve the I<published> behavior
3006 documented in previous versions in the 1.* family; however,
3007 some features that were previously undocumented, or behaved
3008 differently from the documentation, had to be changed in order
3009 to clarify the semantics. Hence, client code that was relying
3010 on some dark areas of C<SQL::Abstract> v1.*
3011 B<might behave differently> in v1.50.
3013 The main changes are:
3019 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3023 support for the { operator => \"..." } construct (to embed literal SQL)
3027 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3031 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3035 defensive programming: check arguments
3039 fixed bug with global logic, which was previously implemented
3040 through global variables yielding side-effects. Prior versions would
3041 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3042 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3043 Now this is interpreted
3044 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3049 fixed semantics of _bindtype on array args
3053 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3054 we just avoid shifting arrays within that tree.
3058 dropped the C<_modlogic> function
3062 =head1 ACKNOWLEDGEMENTS
3064 There are a number of individuals that have really helped out with
3065 this module. Unfortunately, most of them submitted bugs via CPAN
3066 so I have no idea who they are! But the people I do know are:
3068 Ash Berlin (order_by hash term support)
3069 Matt Trout (DBIx::Class support)
3070 Mark Stosberg (benchmarking)
3071 Chas Owens (initial "IN" operator support)
3072 Philip Collins (per-field SQL functions)
3073 Eric Kolve (hashref "AND" support)
3074 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3075 Dan Kubb (support for "quote_char" and "name_sep")
3076 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3077 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3078 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3079 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3080 Oliver Charles (support for "RETURNING" after "INSERT")
3086 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3090 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3092 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3094 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3095 While not an official support venue, C<DBIx::Class> makes heavy use of
3096 C<SQL::Abstract>, and as such list members there are very familiar with
3097 how to create queries.
3101 This module is free software; you may copy this under the same
3102 terms as perl itself (either the GNU General Public License or
3103 the Artistic License)