1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.87';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
188 (map +("-$_", "_render_$_"), qw(op func bind ident literal list)),
192 $opt{expand_unary} = {};
194 return bless \%opt, $class;
197 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
198 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
200 sub _assert_pass_injection_guard {
201 if ($_[1] =~ $_[0]->{injection_guard}) {
202 my $class = ref $_[0];
203 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
204 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
205 . "{injection_guard} attribute to ${class}->new()"
210 #======================================================================
212 #======================================================================
216 my $table = $self->_table(shift);
217 my $data = shift || return;
220 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
221 my ($sql, @bind) = $self->$method($data);
222 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
224 if ($options->{returning}) {
225 my ($s, @b) = $self->_insert_returning($options);
230 return wantarray ? ($sql, @bind) : $sql;
233 # So that subclasses can override INSERT ... RETURNING separately from
234 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
235 sub _insert_returning { shift->_returning(@_) }
238 my ($self, $options) = @_;
240 my $f = $options->{returning};
242 my ($sql, @bind) = $self->render_aqt(
243 $self->_expand_maybe_list_expr($f, undef, -ident)
246 ? $self->_sqlcase(' returning ') . $sql
247 : ($self->_sqlcase(' returning ').$sql, @bind);
250 sub _insert_HASHREF { # explicit list of fields and then values
251 my ($self, $data) = @_;
253 my @fields = sort keys %$data;
255 my ($sql, @bind) = $self->_insert_values($data);
258 $_ = $self->_quote($_) foreach @fields;
259 $sql = "( ".join(", ", @fields).") ".$sql;
261 return ($sql, @bind);
264 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
265 my ($self, $data) = @_;
267 # no names (arrayref) so can't generate bindtype
268 $self->{bindtype} ne 'columns'
269 or belch "can't do 'columns' bindtype when called with arrayref";
271 my (@values, @all_bind);
272 foreach my $value (@$data) {
273 my ($values, @bind) = $self->_insert_value(undef, $value);
274 push @values, $values;
275 push @all_bind, @bind;
277 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
278 return ($sql, @all_bind);
281 sub _insert_ARRAYREFREF { # literal SQL with bind
282 my ($self, $data) = @_;
284 my ($sql, @bind) = @${$data};
285 $self->_assert_bindval_matches_bindtype(@bind);
287 return ($sql, @bind);
291 sub _insert_SCALARREF { # literal SQL without bind
292 my ($self, $data) = @_;
298 my ($self, $data) = @_;
300 my (@values, @all_bind);
301 foreach my $column (sort keys %$data) {
302 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
303 push @values, $values;
304 push @all_bind, @bind;
306 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
307 return ($sql, @all_bind);
311 my ($self, $column, $v) = @_;
313 return $self->render_aqt(
314 $self->_expand_insert_value($column, $v)
318 sub _expand_insert_value {
319 my ($self, $column, $v) = @_;
321 if (ref($v) eq 'ARRAY') {
322 if ($self->{array_datatypes}) {
323 return +{ -bind => [ $column, $v ] };
325 my ($sql, @bind) = @$v;
326 $self->_assert_bindval_matches_bindtype(@bind);
327 return +{ -literal => $v };
329 if (ref($v) eq 'HASH') {
330 if (grep !/^-/, keys %$v) {
331 belch "HASH ref as bind value in insert is not supported";
332 return +{ -bind => [ $column, $v ] };
336 return +{ -bind => [ $column, undef ] };
338 local our $Cur_Col_Meta = $column;
339 return $self->expand_expr($v);
344 #======================================================================
346 #======================================================================
351 my $table = $self->_table(shift);
352 my $data = shift || return;
356 # first build the 'SET' part of the sql statement
357 puke "Unsupported data type specified to \$sql->update"
358 unless ref $data eq 'HASH';
360 my ($sql, @all_bind) = $self->_update_set_values($data);
361 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
365 my($where_sql, @where_bind) = $self->where($where);
367 push @all_bind, @where_bind;
370 if ($options->{returning}) {
371 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
372 $sql .= $returning_sql;
373 push @all_bind, @returning_bind;
376 return wantarray ? ($sql, @all_bind) : $sql;
379 sub _update_set_values {
380 my ($self, $data) = @_;
382 return $self->render_aqt(
383 $self->_expand_update_set_values($data),
387 sub _expand_update_set_values {
388 my ($self, $data) = @_;
389 $self->_expand_maybe_list_expr( [
392 $set = { -bind => $_ } unless defined $set;
393 +{ -op => [ '=', $self->_expand_ident(-ident => $k), $set ] };
399 ? ($self->{array_datatypes}
400 ? [ $k, +{ -bind => [ $k, $v ] } ]
401 : [ $k, +{ -literal => $v } ])
403 local our $Cur_Col_Meta = $k;
404 [ $k, $self->_expand_expr($v) ]
411 # So that subclasses can override UPDATE ... RETURNING separately from
413 sub _update_returning { shift->_returning(@_) }
417 #======================================================================
419 #======================================================================
424 my $table = $self->_table(shift);
425 my $fields = shift || '*';
429 my ($fields_sql, @bind) = $self->_select_fields($fields);
431 my ($where_sql, @where_bind) = $self->where($where, $order);
432 push @bind, @where_bind;
434 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
435 $self->_sqlcase('from'), $table)
438 return wantarray ? ($sql, @bind) : $sql;
442 my ($self, $fields) = @_;
443 return $fields unless ref($fields);
444 return $self->render_aqt(
445 $self->_expand_maybe_list_expr($fields, undef, '-ident')
449 #======================================================================
451 #======================================================================
456 my $table = $self->_table(shift);
460 my($where_sql, @bind) = $self->where($where);
461 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
463 if ($options->{returning}) {
464 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
465 $sql .= $returning_sql;
466 push @bind, @returning_bind;
469 return wantarray ? ($sql, @bind) : $sql;
472 # So that subclasses can override DELETE ... RETURNING separately from
474 sub _delete_returning { shift->_returning(@_) }
478 #======================================================================
480 #======================================================================
484 # Finally, a separate routine just to handle WHERE clauses
486 my ($self, $where, $order) = @_;
488 local $self->{convert_where} = $self->{convert};
491 my ($sql, @bind) = defined($where)
492 ? $self->_recurse_where($where)
494 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
498 my ($order_sql, @order_bind) = $self->_order_by($order);
500 push @bind, @order_bind;
503 return wantarray ? ($sql, @bind) : $sql;
507 my ($self, $expr, $default_scalar_to) = @_;
508 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
509 $self->_expand_expr($expr);
513 my ($self, $aqt) = @_;
514 my ($k, $v, @rest) = %$aqt;
516 if (my $meth = $self->{render}{$k}) {
517 return $self->$meth($v);
519 die "notreached: $k";
523 my ($self, $expr) = @_;
524 $self->render_aqt($self->expand_expr($expr));
528 my ($self, $expr, $logic, $default_scalar_to) = @_;
529 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
530 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
531 return undef unless defined($expr);
532 if (ref($expr) eq 'HASH') {
533 if (keys %$expr > 1) {
537 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
541 return undef unless keys %$expr;
542 return $self->_expand_expr_hashpair(%$expr, $logic);
544 if (ref($expr) eq 'ARRAY') {
545 my $logic = lc($logic || $self->{logic});
546 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
549 (ref($_) eq 'ARRAY' and @$_)
550 or (ref($_) eq 'HASH' and %$_)
556 while (my ($el) = splice @expr, 0, 1) {
557 puke "Supplying an empty left hand side argument is not supported in array-pairs"
558 unless defined($el) and length($el);
559 my $elref = ref($el);
561 local $Expand_Depth = 0;
562 push(@res, grep defined, $self->_expand_expr({ $el, shift(@expr) }));
563 } elsif ($elref eq 'ARRAY') {
564 push(@res, grep defined, $self->_expand_expr($el)) if @$el;
565 } elsif (my $l = is_literal_value($el)) {
566 push @res, { -literal => $l };
567 } elsif ($elref eq 'HASH') {
568 local $Expand_Depth = 0;
569 push @res, grep defined, $self->_expand_expr($el) if %$el;
574 return { -op => [ $logic, @res ] };
576 if (my $literal = is_literal_value($expr)) {
577 return +{ -literal => $literal };
579 if (!ref($expr) or Scalar::Util::blessed($expr)) {
580 if (my $d = $Default_Scalar_To) {
581 return $self->_expand_expr({ $d => $expr });
583 if (my $m = our $Cur_Col_Meta) {
584 return +{ -bind => [ $m, $expr ] };
586 return +{ -bind => [ undef, $expr ] };
591 sub _expand_expr_hashpair {
592 my ($self, $k, $v, $logic) = @_;
593 unless (defined($k) and length($k)) {
594 if (defined($k) and my $literal = is_literal_value($v)) {
595 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
596 return { -literal => $literal };
598 puke "Supplying an empty left hand side argument is not supported";
601 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
602 if ($k =~ s/ [_\s]? \d+ $//x ) {
603 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
604 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
607 # DBIx::Class requires a nest warning to be emitted once but the private
608 # method it overrode to do so no longer exists
609 if ($self->{is_dbic_sqlmaker}) {
610 unless (our $Nest_Warned) {
612 "-nest in search conditions is deprecated, you most probably wanted:\n"
613 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
618 return $self->_expand_expr($v);
622 return $self->_expand_expr($v);
624 puke "-bool => undef not supported" unless defined($v);
625 return $self->_expand_ident(-ident => $v);
628 return { -op => [ 'not', $self->_expand_expr($v) ] };
630 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
633 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
636 if (my ($logic) = $k =~ /^-(and|or)$/i) {
637 if (ref($v) eq 'HASH') {
638 return $self->_expand_expr($v, $logic);
640 if (ref($v) eq 'ARRAY') {
641 return $self->_expand_expr($v, $logic);
646 $op =~ s/^-// if length($op) > 1;
648 # top level special ops are illegal in general
649 # note that, arguably, if it makes no sense at top level, it also
650 # makes no sense on the other side of an = sign or similar but DBIC
651 # gets disappointingly upset if I disallow it
653 (our $Expand_Depth) == 1
654 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
656 puke "Illegal use of top-level '-$op'"
658 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
659 return { -op => [ $op, $v ] };
662 if ($k eq '-value') {
663 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
665 if ($k eq '-ident') {
666 return $self->_expand_ident(-ident => $v);
668 if (my $custom = $self->{expand_unary}{$k}) {
669 return $self->$custom($v);
671 if ($self->{render}{$k}) {
677 and (keys %$v)[0] =~ /^-/
679 my ($func) = $k =~ /^-(.*)$/;
680 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
681 return +{ -op => [ $func, $self->_expand_expr($v) ] };
683 return +{ -func => [ $func, $self->_expand_expr($v) ] };
685 if (!ref($v) or is_literal_value($v)) {
686 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
693 and exists $v->{-value}
694 and not defined $v->{-value}
697 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
699 if (!ref($v) or Scalar::Util::blessed($v)) {
700 my $d = our $Default_Scalar_To;
704 $self->_expand_ident(-ident => $k),
706 ? $self->_expand_expr($d => $v)
707 : { -bind => [ $k, $v ] }
712 if (ref($v) eq 'HASH') {
716 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
720 return undef unless keys %$v;
722 my $op = join ' ', split '_', (map lc, $vk =~ /^-?(.*)$/)[0];
723 $self->_assert_pass_injection_guard($op);
724 if ($op =~ s/ [_\s]? \d+ $//x ) {
725 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
726 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
728 if ($op =~ /^(?:not )?between$/) {
729 local our $Cur_Col_Meta = $k;
730 my @rhs = map $self->_expand_expr($_),
731 ref($vv) eq 'ARRAY' ? @$vv : $vv;
733 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
735 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
737 puke "Operator '${\uc($op)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
741 $self->_expand_ident(-ident => $k),
745 if ($op =~ /^(?:not )?in$/) {
746 if (my $literal = is_literal_value($vv)) {
747 my ($sql, @bind) = @$literal;
748 my $opened_sql = $self->_open_outer_paren($sql);
750 $op, $self->_expand_ident(-ident => $k),
751 [ { -literal => [ $opened_sql, @bind ] } ]
755 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
756 . "-${\uc($op)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
757 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
758 . 'will emit the logically correct SQL instead of raising this exception)'
760 puke("Argument passed to the '${\uc($op)}' operator can not be undefined")
762 my @rhs = map $self->_expand_expr($_),
763 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
764 map { defined($_) ? $_: puke($undef_err) }
765 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
766 return $self->${\($op =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
770 $self->_expand_ident(-ident => $k),
774 if ($op eq 'ident') {
775 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
776 puke "-$op requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
780 $self->_expand_ident(-ident => $k),
781 $self->_expand_ident(-ident => $vv),
784 if ($op eq 'value') {
785 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
788 $self->_expand_ident(-ident => $k),
789 { -bind => [ $k, $vv ] }
792 if ($op =~ /^is(?: not)?$/) {
793 puke "$op can only take undef as argument"
797 and exists($vv->{-value})
798 and !defined($vv->{-value})
800 return +{ -op => [ $op.' null', $self->_expand_ident(-ident => $k) ] };
802 if ($op =~ /^(and|or)$/) {
803 if (ref($vv) eq 'HASH') {
806 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
811 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
812 return { -op => [ $op, $self->_expand_ident(-ident => $k), $vv ] };
814 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
817 $self->_expand_ident(-ident => $k),
818 { -op => [ $op, $vv ] }
821 if (ref($vv) eq 'ARRAY') {
822 my ($logic, @values) = (
823 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
828 $op =~ $self->{inequality_op}
829 or $op =~ $self->{not_like_op}
831 if (lc($logic) eq '-or' and @values > 1) {
832 belch "A multi-element arrayref as an argument to the inequality op '${\uc($op)}' "
833 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
834 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
839 # try to DWIM on equality operators
841 $op =~ $self->{equality_op} ? $self->sqlfalse
842 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
843 : $op =~ $self->{inequality_op} ? $self->sqltrue
844 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
845 : puke "operator '$op' applied on an empty array (field '$k')";
849 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
857 and exists $vv->{-value}
858 and not defined $vv->{-value}
862 $op =~ /^not$/i ? 'is not' # legacy
863 : $op =~ $self->{equality_op} ? 'is'
864 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
865 : $op =~ $self->{inequality_op} ? 'is not'
866 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
867 : puke "unexpected operator '$op' with undef operand";
868 return +{ -op => [ $is.' null', $self->_expand_ident(-ident => $k) ] };
870 local our $Cur_Col_Meta = $k;
873 $self->_expand_ident(-ident => $k),
874 $self->_expand_expr($vv)
877 if (ref($v) eq 'ARRAY') {
878 return $self->sqlfalse unless @$v;
879 $self->_debug("ARRAY($k) means distribute over elements");
881 $v->[0] =~ /^-((?:and|or))$/i
882 ? ($v = [ @{$v}[1..$#$v] ], $1)
883 : ($self->{logic} || 'or')
887 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
890 if (my $literal = is_literal_value($v)) {
892 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
895 my ($sql, @bind) = @$literal;
896 if ($self->{bindtype} eq 'columns') {
898 $self->_assert_bindval_matches_bindtype($_);
901 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
907 my ($self, undef, $body) = @_;
908 my @parts = map split(/\Q${\($self->{name_sep}||'.')}\E/, $_),
909 ref($body) ? @$body : $body;
910 return { -ident => $parts[-1] } if $self->{_dequalify_idents};
911 unless ($self->{quote_char}) {
912 $self->_assert_pass_injection_guard($_) for @parts;
914 return +{ -ident => \@parts };
918 my ($self, $where, $logic) = @_;
920 # Special case: top level simple string treated as literal
922 my $where_exp = (ref($where)
923 ? $self->_expand_expr($where, $logic)
924 : { -literal => [ $where ] });
926 # dispatch expanded expression
928 my ($sql, @bind) = defined($where_exp) ? $self->render_aqt($where_exp) : (undef);
929 # DBIx::Class used to call _recurse_where in scalar context
930 # something else might too...
932 return ($sql, @bind);
935 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
941 my ($self, $ident) = @_;
943 return $self->_convert($self->_quote($ident));
946 my %unop_postfix = map +($_ => 1),
947 'is null', 'is not null',
955 my ($self, $args) = @_;
956 my ($left, $low, $high) = @$args;
957 my ($rhsql, @rhbind) = do {
959 puke "Single arg to between must be a literal"
960 unless $low->{-literal};
963 my ($l, $h) = map [ $self->render_aqt($_) ], $low, $high;
964 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
965 @{$l}[1..$#$l], @{$h}[1..$#$h])
968 my ($lhsql, @lhbind) = $self->render_aqt($left);
970 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
974 }), 'between', 'not between'),
978 my ($self, $args) = @_;
979 my ($lhs, $rhs) = @$args;
982 my ($sql, @bind) = $self->render_aqt($_);
983 push @in_bind, @bind;
986 my ($lhsql, @lbind) = $self->render_aqt($lhs);
988 $lhsql.' '.$self->_sqlcase($op).' ( '
999 my ($op, @args) = @$v;
1000 $op =~ s/^-// if length($op) > 1;
1002 if (my $h = $special{$op}) {
1003 return $self->$h(\@args);
1005 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
1006 if ($us and @args > 1) {
1007 puke "Special op '${op}' requires first value to be identifier"
1008 unless my ($ident) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1009 my $k = join(($self->{name_sep}||'.'), @$ident);
1010 local our $Expand_Depth = 1;
1011 return $self->${\($us->{handler})}($k, $op, $args[1]);
1013 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1014 return $self->${\($us->{handler})}($op, $args[0]);
1016 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1017 if (@args == 1 and $op !~ /^(and|or)$/) {
1018 my ($expr_sql, @bind) = $self->render_aqt($args[0]);
1019 my $op_sql = $self->_sqlcase($final_op);
1021 $unop_postfix{lc($final_op)}
1022 ? "${expr_sql} ${op_sql}"
1023 : "${op_sql} ${expr_sql}"
1025 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1027 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @args;
1028 return '' unless @parts;
1029 my $is_andor = !!($op =~ /^(and|or)$/);
1030 return @{$parts[0]} if $is_andor and @parts == 1;
1031 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1032 ' '.$self->_sqlcase($final_op).' ',
1037 map @{$_}[1..$#$_], @parts
1044 my ($self, $list) = @_;
1045 my @parts = grep length($_->[0]), map [ $self->render_aqt($_) ], @$list;
1046 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1050 my ($self, $rest) = @_;
1051 my ($func, @args) = @$rest;
1055 push @arg_sql, shift @x;
1057 } map [ $self->render_aqt($_) ], @args;
1058 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1062 my ($self, $bind) = @_;
1063 return ($self->_convert('?'), $self->_bindtype(@$bind));
1066 sub _render_literal {
1067 my ($self, $literal) = @_;
1068 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1072 # Some databases (SQLite) treat col IN (1, 2) different from
1073 # col IN ( (1, 2) ). Use this to strip all outer parens while
1074 # adding them back in the corresponding method
1075 sub _open_outer_paren {
1076 my ($self, $sql) = @_;
1078 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1080 # there are closing parens inside, need the heavy duty machinery
1081 # to reevaluate the extraction starting from $sql (full reevaluation)
1082 if ($inner =~ /\)/) {
1083 require Text::Balanced;
1085 my (undef, $remainder) = do {
1086 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1088 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1091 # the entire expression needs to be a balanced bracketed thing
1092 # (after an extract no remainder sans trailing space)
1093 last if defined $remainder and $remainder =~ /\S/;
1103 #======================================================================
1105 #======================================================================
1107 sub _expand_order_by {
1108 my ($self, $arg) = @_;
1110 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1112 my $expander = sub {
1113 my ($self, $dir, $expr) = @_;
1114 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1115 foreach my $arg (@to_expand) {
1119 and grep /^-(asc|desc)$/, keys %$arg
1121 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1124 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1125 map $self->expand_expr($_, -ident),
1126 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1127 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1130 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1131 sub { shift->$expander(asc => @_) },
1132 sub { shift->$expander(desc => @_) },
1135 return $self->$expander(undef, $arg);
1139 my ($self, $arg) = @_;
1141 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1143 my ($sql, @bind) = $self->render_aqt($expanded);
1145 return '' unless length($sql);
1147 my $final_sql = $self->_sqlcase(' order by ').$sql;
1149 return wantarray ? ($final_sql, @bind) : $final_sql;
1152 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1154 sub _order_by_chunks {
1155 my ($self, $arg) = @_;
1157 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1159 return $self->_chunkify_order_by($expanded);
1162 sub _chunkify_order_by {
1163 my ($self, $expanded) = @_;
1165 return grep length, $self->render_aqt($expanded)
1166 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1169 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1170 return map $self->_chunkify_order_by($_), @$l;
1172 return [ $self->render_aqt($_) ];
1176 #======================================================================
1177 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1178 #======================================================================
1184 $self->_expand_maybe_list_expr($from, undef, -ident)
1189 #======================================================================
1191 #======================================================================
1193 sub _expand_maybe_list_expr {
1194 my ($self, $expr, $logic, $default) = @_;
1196 if (ref($expr) eq 'ARRAY') {
1198 map $self->expand_expr($_, $default), @$expr
1205 return $self->expand_expr($e, $default);
1208 # highly optimized, as it's called way too often
1210 # my ($self, $label) = @_;
1212 return '' unless defined $_[1];
1213 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1214 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1216 unless ($_[0]->{quote_char}) {
1217 if (ref($_[1]) eq 'ARRAY') {
1218 return join($_[0]->{name_sep}||'.', @{$_[1]});
1220 $_[0]->_assert_pass_injection_guard($_[1]);
1225 my $qref = ref $_[0]->{quote_char};
1227 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1228 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1229 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1231 my $esc = $_[0]->{escape_char} || $r;
1233 # parts containing * are naturally unquoted
1235 $_[0]->{name_sep}||'',
1239 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1241 (ref($_[1]) eq 'ARRAY'
1245 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1253 # Conversion, if applicable
1255 #my ($self, $arg) = @_;
1256 if ($_[0]->{convert_where}) {
1257 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1264 #my ($self, $col, @vals) = @_;
1265 # called often - tighten code
1266 return $_[0]->{bindtype} eq 'columns'
1267 ? map {[$_[1], $_]} @_[2 .. $#_]
1272 # Dies if any element of @bind is not in [colname => value] format
1273 # if bindtype is 'columns'.
1274 sub _assert_bindval_matches_bindtype {
1275 # my ($self, @bind) = @_;
1277 if ($self->{bindtype} eq 'columns') {
1279 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1280 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1286 sub _join_sql_clauses {
1287 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1289 if (@$clauses_aref > 1) {
1290 my $join = " " . $self->_sqlcase($logic) . " ";
1291 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1292 return ($sql, @$bind_aref);
1294 elsif (@$clauses_aref) {
1295 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1298 return (); # if no SQL, ignore @$bind_aref
1303 # Fix SQL case, if so requested
1305 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1306 # don't touch the argument ... crooked logic, but let's not change it!
1307 return $_[0]->{case} ? $_[1] : uc($_[1]);
1311 #======================================================================
1312 # DISPATCHING FROM REFKIND
1313 #======================================================================
1316 my ($self, $data) = @_;
1318 return 'UNDEF' unless defined $data;
1320 # blessed objects are treated like scalars
1321 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1323 return 'SCALAR' unless $ref;
1326 while ($ref eq 'REF') {
1328 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1332 return ($ref||'SCALAR') . ('REF' x $n_steps);
1336 my ($self, $data) = @_;
1337 my @try = ($self->_refkind($data));
1338 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1339 push @try, 'FALLBACK';
1343 sub _METHOD_FOR_refkind {
1344 my ($self, $meth_prefix, $data) = @_;
1347 for (@{$self->_try_refkind($data)}) {
1348 $method = $self->can($meth_prefix."_".$_)
1352 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1356 sub _SWITCH_refkind {
1357 my ($self, $data, $dispatch_table) = @_;
1360 for (@{$self->_try_refkind($data)}) {
1361 $coderef = $dispatch_table->{$_}
1365 puke "no dispatch entry for ".$self->_refkind($data)
1374 #======================================================================
1375 # VALUES, GENERATE, AUTOLOAD
1376 #======================================================================
1378 # LDNOTE: original code from nwiger, didn't touch code in that section
1379 # I feel the AUTOLOAD stuff should not be the default, it should
1380 # only be activated on explicit demand by user.
1384 my $data = shift || return;
1385 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1386 unless ref $data eq 'HASH';
1389 foreach my $k (sort keys %$data) {
1390 my $v = $data->{$k};
1391 $self->_SWITCH_refkind($v, {
1393 if ($self->{array_datatypes}) { # array datatype
1394 push @all_bind, $self->_bindtype($k, $v);
1396 else { # literal SQL with bind
1397 my ($sql, @bind) = @$v;
1398 $self->_assert_bindval_matches_bindtype(@bind);
1399 push @all_bind, @bind;
1402 ARRAYREFREF => sub { # literal SQL with bind
1403 my ($sql, @bind) = @${$v};
1404 $self->_assert_bindval_matches_bindtype(@bind);
1405 push @all_bind, @bind;
1407 SCALARREF => sub { # literal SQL without bind
1409 SCALAR_or_UNDEF => sub {
1410 push @all_bind, $self->_bindtype($k, $v);
1421 my(@sql, @sqlq, @sqlv);
1425 if ($ref eq 'HASH') {
1426 for my $k (sort keys %$_) {
1429 my $label = $self->_quote($k);
1430 if ($r eq 'ARRAY') {
1431 # literal SQL with bind
1432 my ($sql, @bind) = @$v;
1433 $self->_assert_bindval_matches_bindtype(@bind);
1434 push @sqlq, "$label = $sql";
1436 } elsif ($r eq 'SCALAR') {
1437 # literal SQL without bind
1438 push @sqlq, "$label = $$v";
1440 push @sqlq, "$label = ?";
1441 push @sqlv, $self->_bindtype($k, $v);
1444 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1445 } elsif ($ref eq 'ARRAY') {
1446 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1449 if ($r eq 'ARRAY') { # literal SQL with bind
1450 my ($sql, @bind) = @$v;
1451 $self->_assert_bindval_matches_bindtype(@bind);
1454 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1455 # embedded literal SQL
1462 push @sql, '(' . join(', ', @sqlq) . ')';
1463 } elsif ($ref eq 'SCALAR') {
1467 # strings get case twiddled
1468 push @sql, $self->_sqlcase($_);
1472 my $sql = join ' ', @sql;
1474 # this is pretty tricky
1475 # if ask for an array, return ($stmt, @bind)
1476 # otherwise, s/?/shift @sqlv/ to put it inline
1478 return ($sql, @sqlv);
1480 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1481 ref $d ? $d->[1] : $d/e;
1490 # This allows us to check for a local, then _form, attr
1492 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1493 return $self->generate($name, @_);
1504 SQL::Abstract - Generate SQL from Perl data structures
1510 my $sql = SQL::Abstract->new;
1512 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1514 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1516 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1518 my($stmt, @bind) = $sql->delete($table, \%where);
1520 # Then, use these in your DBI statements
1521 my $sth = $dbh->prepare($stmt);
1522 $sth->execute(@bind);
1524 # Just generate the WHERE clause
1525 my($stmt, @bind) = $sql->where(\%where, $order);
1527 # Return values in the same order, for hashed queries
1528 # See PERFORMANCE section for more details
1529 my @bind = $sql->values(\%fieldvals);
1533 This module was inspired by the excellent L<DBIx::Abstract>.
1534 However, in using that module I found that what I really wanted
1535 to do was generate SQL, but still retain complete control over my
1536 statement handles and use the DBI interface. So, I set out to
1537 create an abstract SQL generation module.
1539 While based on the concepts used by L<DBIx::Abstract>, there are
1540 several important differences, especially when it comes to WHERE
1541 clauses. I have modified the concepts used to make the SQL easier
1542 to generate from Perl data structures and, IMO, more intuitive.
1543 The underlying idea is for this module to do what you mean, based
1544 on the data structures you provide it. The big advantage is that
1545 you don't have to modify your code every time your data changes,
1546 as this module figures it out.
1548 To begin with, an SQL INSERT is as easy as just specifying a hash
1549 of C<key=value> pairs:
1552 name => 'Jimbo Bobson',
1553 phone => '123-456-7890',
1554 address => '42 Sister Lane',
1555 city => 'St. Louis',
1556 state => 'Louisiana',
1559 The SQL can then be generated with this:
1561 my($stmt, @bind) = $sql->insert('people', \%data);
1563 Which would give you something like this:
1565 $stmt = "INSERT INTO people
1566 (address, city, name, phone, state)
1567 VALUES (?, ?, ?, ?, ?)";
1568 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1569 '123-456-7890', 'Louisiana');
1571 These are then used directly in your DBI code:
1573 my $sth = $dbh->prepare($stmt);
1574 $sth->execute(@bind);
1576 =head2 Inserting and Updating Arrays
1578 If your database has array types (like for example Postgres),
1579 activate the special option C<< array_datatypes => 1 >>
1580 when creating the C<SQL::Abstract> object.
1581 Then you may use an arrayref to insert and update database array types:
1583 my $sql = SQL::Abstract->new(array_datatypes => 1);
1585 planets => [qw/Mercury Venus Earth Mars/]
1588 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1592 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1594 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1597 =head2 Inserting and Updating SQL
1599 In order to apply SQL functions to elements of your C<%data> you may
1600 specify a reference to an arrayref for the given hash value. For example,
1601 if you need to execute the Oracle C<to_date> function on a value, you can
1602 say something like this:
1606 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1609 The first value in the array is the actual SQL. Any other values are
1610 optional and would be included in the bind values array. This gives
1613 my($stmt, @bind) = $sql->insert('people', \%data);
1615 $stmt = "INSERT INTO people (name, date_entered)
1616 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1617 @bind = ('Bill', '03/02/2003');
1619 An UPDATE is just as easy, all you change is the name of the function:
1621 my($stmt, @bind) = $sql->update('people', \%data);
1623 Notice that your C<%data> isn't touched; the module will generate
1624 the appropriately quirky SQL for you automatically. Usually you'll
1625 want to specify a WHERE clause for your UPDATE, though, which is
1626 where handling C<%where> hashes comes in handy...
1628 =head2 Complex where statements
1630 This module can generate pretty complicated WHERE statements
1631 easily. For example, simple C<key=value> pairs are taken to mean
1632 equality, and if you want to see if a field is within a set
1633 of values, you can use an arrayref. Let's say we wanted to
1634 SELECT some data based on this criteria:
1637 requestor => 'inna',
1638 worker => ['nwiger', 'rcwe', 'sfz'],
1639 status => { '!=', 'completed' }
1642 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1644 The above would give you something like this:
1646 $stmt = "SELECT * FROM tickets WHERE
1647 ( requestor = ? ) AND ( status != ? )
1648 AND ( worker = ? OR worker = ? OR worker = ? )";
1649 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1651 Which you could then use in DBI code like so:
1653 my $sth = $dbh->prepare($stmt);
1654 $sth->execute(@bind);
1660 The methods are simple. There's one for every major SQL operation,
1661 and a constructor you use first. The arguments are specified in a
1662 similar order for each method (table, then fields, then a where
1663 clause) to try and simplify things.
1665 =head2 new(option => 'value')
1667 The C<new()> function takes a list of options and values, and returns
1668 a new B<SQL::Abstract> object which can then be used to generate SQL
1669 through the methods below. The options accepted are:
1675 If set to 'lower', then SQL will be generated in all lowercase. By
1676 default SQL is generated in "textbook" case meaning something like:
1678 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1680 Any setting other than 'lower' is ignored.
1684 This determines what the default comparison operator is. By default
1685 it is C<=>, meaning that a hash like this:
1687 %where = (name => 'nwiger', email => 'nate@wiger.org');
1689 Will generate SQL like this:
1691 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1693 However, you may want loose comparisons by default, so if you set
1694 C<cmp> to C<like> you would get SQL such as:
1696 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1698 You can also override the comparison on an individual basis - see
1699 the huge section on L</"WHERE CLAUSES"> at the bottom.
1701 =item sqltrue, sqlfalse
1703 Expressions for inserting boolean values within SQL statements.
1704 By default these are C<1=1> and C<1=0>. They are used
1705 by the special operators C<-in> and C<-not_in> for generating
1706 correct SQL even when the argument is an empty array (see below).
1710 This determines the default logical operator for multiple WHERE
1711 statements in arrays or hashes. If absent, the default logic is "or"
1712 for arrays, and "and" for hashes. This means that a WHERE
1716 event_date => {'>=', '2/13/99'},
1717 event_date => {'<=', '4/24/03'},
1720 will generate SQL like this:
1722 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1724 This is probably not what you want given this query, though (look
1725 at the dates). To change the "OR" to an "AND", simply specify:
1727 my $sql = SQL::Abstract->new(logic => 'and');
1729 Which will change the above C<WHERE> to:
1731 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1733 The logic can also be changed locally by inserting
1734 a modifier in front of an arrayref:
1736 @where = (-and => [event_date => {'>=', '2/13/99'},
1737 event_date => {'<=', '4/24/03'} ]);
1739 See the L</"WHERE CLAUSES"> section for explanations.
1743 This will automatically convert comparisons using the specified SQL
1744 function for both column and value. This is mostly used with an argument
1745 of C<upper> or C<lower>, so that the SQL will have the effect of
1746 case-insensitive "searches". For example, this:
1748 $sql = SQL::Abstract->new(convert => 'upper');
1749 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1751 Will turn out the following SQL:
1753 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1755 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1756 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1757 not validate this option; it will just pass through what you specify verbatim).
1761 This is a kludge because many databases suck. For example, you can't
1762 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1763 Instead, you have to use C<bind_param()>:
1765 $sth->bind_param(1, 'reg data');
1766 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1768 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1769 which loses track of which field each slot refers to. Fear not.
1771 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1772 Currently, you can specify either C<normal> (default) or C<columns>. If you
1773 specify C<columns>, you will get an array that looks like this:
1775 my $sql = SQL::Abstract->new(bindtype => 'columns');
1776 my($stmt, @bind) = $sql->insert(...);
1779 [ 'column1', 'value1' ],
1780 [ 'column2', 'value2' ],
1781 [ 'column3', 'value3' ],
1784 You can then iterate through this manually, using DBI's C<bind_param()>.
1786 $sth->prepare($stmt);
1789 my($col, $data) = @$_;
1790 if ($col eq 'details' || $col eq 'comments') {
1791 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1792 } elsif ($col eq 'image') {
1793 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1795 $sth->bind_param($i, $data);
1799 $sth->execute; # execute without @bind now
1801 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1802 Basically, the advantage is still that you don't have to care which fields
1803 are or are not included. You could wrap that above C<for> loop in a simple
1804 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1805 get a layer of abstraction over manual SQL specification.
1807 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1808 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1809 will expect the bind values in this format.
1813 This is the character that a table or column name will be quoted
1814 with. By default this is an empty string, but you could set it to
1815 the character C<`>, to generate SQL like this:
1817 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1819 Alternatively, you can supply an array ref of two items, the first being the left
1820 hand quote character, and the second the right hand quote character. For
1821 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1822 that generates SQL like this:
1824 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1826 Quoting is useful if you have tables or columns names that are reserved
1827 words in your database's SQL dialect.
1831 This is the character that will be used to escape L</quote_char>s appearing
1832 in an identifier before it has been quoted.
1834 The parameter default in case of a single L</quote_char> character is the quote
1837 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1838 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1839 of the B<opening (left)> L</quote_char> within the identifier are currently left
1840 untouched. The default for opening-closing-style quotes may change in future
1841 versions, thus you are B<strongly encouraged> to specify the escape character
1846 This is the character that separates a table and column name. It is
1847 necessary to specify this when the C<quote_char> option is selected,
1848 so that tables and column names can be individually quoted like this:
1850 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1852 =item injection_guard
1854 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1855 column name specified in a query structure. This is a safety mechanism to avoid
1856 injection attacks when mishandling user input e.g.:
1858 my %condition_as_column_value_pairs = get_values_from_user();
1859 $sqla->select( ... , \%condition_as_column_value_pairs );
1861 If the expression matches an exception is thrown. Note that literal SQL
1862 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1864 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1866 =item array_datatypes
1868 When this option is true, arrayrefs in INSERT or UPDATE are
1869 interpreted as array datatypes and are passed directly
1871 When this option is false, arrayrefs are interpreted
1872 as literal SQL, just like refs to arrayrefs
1873 (but this behavior is for backwards compatibility; when writing
1874 new queries, use the "reference to arrayref" syntax
1880 Takes a reference to a list of "special operators"
1881 to extend the syntax understood by L<SQL::Abstract>.
1882 See section L</"SPECIAL OPERATORS"> for details.
1886 Takes a reference to a list of "unary operators"
1887 to extend the syntax understood by L<SQL::Abstract>.
1888 See section L</"UNARY OPERATORS"> for details.
1894 =head2 insert($table, \@values || \%fieldvals, \%options)
1896 This is the simplest function. You simply give it a table name
1897 and either an arrayref of values or hashref of field/value pairs.
1898 It returns an SQL INSERT statement and a list of bind values.
1899 See the sections on L</"Inserting and Updating Arrays"> and
1900 L</"Inserting and Updating SQL"> for information on how to insert
1901 with those data types.
1903 The optional C<\%options> hash reference may contain additional
1904 options to generate the insert SQL. Currently supported options
1911 Takes either a scalar of raw SQL fields, or an array reference of
1912 field names, and adds on an SQL C<RETURNING> statement at the end.
1913 This allows you to return data generated by the insert statement
1914 (such as row IDs) without performing another C<SELECT> statement.
1915 Note, however, this is not part of the SQL standard and may not
1916 be supported by all database engines.
1920 =head2 update($table, \%fieldvals, \%where, \%options)
1922 This takes a table, hashref of field/value pairs, and an optional
1923 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1925 See the sections on L</"Inserting and Updating Arrays"> and
1926 L</"Inserting and Updating SQL"> for information on how to insert
1927 with those data types.
1929 The optional C<\%options> hash reference may contain additional
1930 options to generate the update SQL. Currently supported options
1937 See the C<returning> option to
1938 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1942 =head2 select($source, $fields, $where, $order)
1944 This returns a SQL SELECT statement and associated list of bind values, as
1945 specified by the arguments:
1951 Specification of the 'FROM' part of the statement.
1952 The argument can be either a plain scalar (interpreted as a table
1953 name, will be quoted), or an arrayref (interpreted as a list
1954 of table names, joined by commas, quoted), or a scalarref
1955 (literal SQL, not quoted).
1959 Specification of the list of fields to retrieve from
1961 The argument can be either an arrayref (interpreted as a list
1962 of field names, will be joined by commas and quoted), or a
1963 plain scalar (literal SQL, not quoted).
1964 Please observe that this API is not as flexible as that of
1965 the first argument C<$source>, for backwards compatibility reasons.
1969 Optional argument to specify the WHERE part of the query.
1970 The argument is most often a hashref, but can also be
1971 an arrayref or plain scalar --
1972 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1976 Optional argument to specify the ORDER BY part of the query.
1977 The argument can be a scalar, a hashref or an arrayref
1978 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1984 =head2 delete($table, \%where, \%options)
1986 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1987 It returns an SQL DELETE statement and list of bind values.
1989 The optional C<\%options> hash reference may contain additional
1990 options to generate the delete SQL. Currently supported options
1997 See the C<returning> option to
1998 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2002 =head2 where(\%where, $order)
2004 This is used to generate just the WHERE clause. For example,
2005 if you have an arbitrary data structure and know what the
2006 rest of your SQL is going to look like, but want an easy way
2007 to produce a WHERE clause, use this. It returns an SQL WHERE
2008 clause and list of bind values.
2011 =head2 values(\%data)
2013 This just returns the values from the hash C<%data>, in the same
2014 order that would be returned from any of the other above queries.
2015 Using this allows you to markedly speed up your queries if you
2016 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2018 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2020 Warning: This is an experimental method and subject to change.
2022 This returns arbitrarily generated SQL. It's a really basic shortcut.
2023 It will return two different things, depending on return context:
2025 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2026 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2028 These would return the following:
2030 # First calling form
2031 $stmt = "CREATE TABLE test (?, ?)";
2032 @bind = (field1, field2);
2034 # Second calling form
2035 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2037 Depending on what you're trying to do, it's up to you to choose the correct
2038 format. In this example, the second form is what you would want.
2042 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2046 ALTER SESSION SET nls_date_format = 'MM/YY'
2048 You get the idea. Strings get their case twiddled, but everything
2049 else remains verbatim.
2051 =head1 EXPORTABLE FUNCTIONS
2053 =head2 is_plain_value
2055 Determines if the supplied argument is a plain value as understood by this
2060 =item * The value is C<undef>
2062 =item * The value is a non-reference
2064 =item * The value is an object with stringification overloading
2066 =item * The value is of the form C<< { -value => $anything } >>
2070 On failure returns C<undef>, on success returns a B<scalar> reference
2071 to the original supplied argument.
2077 The stringification overloading detection is rather advanced: it takes
2078 into consideration not only the presence of a C<""> overload, but if that
2079 fails also checks for enabled
2080 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2081 on either C<0+> or C<bool>.
2083 Unfortunately testing in the field indicates that this
2084 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2085 but only when very large numbers of stringifying objects are involved.
2086 At the time of writing ( Sep 2014 ) there is no clear explanation of
2087 the direct cause, nor is there a manageably small test case that reliably
2088 reproduces the problem.
2090 If you encounter any of the following exceptions in B<random places within
2091 your application stack> - this module may be to blame:
2093 Operation "ne": no method found,
2094 left argument in overloaded package <something>,
2095 right argument in overloaded package <something>
2099 Stub found while resolving method "???" overloading """" in package <something>
2101 If you fall victim to the above - please attempt to reduce the problem
2102 to something that could be sent to the L<SQL::Abstract developers
2103 |DBIx::Class/GETTING HELP/SUPPORT>
2104 (either publicly or privately). As a workaround in the meantime you can
2105 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2106 value, which will most likely eliminate your problem (at the expense of
2107 not being able to properly detect exotic forms of stringification).
2109 This notice and environment variable will be removed in a future version,
2110 as soon as the underlying problem is found and a reliable workaround is
2115 =head2 is_literal_value
2117 Determines if the supplied argument is a literal value as understood by this
2122 =item * C<\$sql_string>
2124 =item * C<\[ $sql_string, @bind_values ]>
2128 On failure returns C<undef>, on success returns an B<array> reference
2129 containing the unpacked version of the supplied literal SQL and bind values.
2131 =head1 WHERE CLAUSES
2135 This module uses a variation on the idea from L<DBIx::Abstract>. It
2136 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2137 module is that things in arrays are OR'ed, and things in hashes
2140 The easiest way to explain is to show lots of examples. After
2141 each C<%where> hash shown, it is assumed you used:
2143 my($stmt, @bind) = $sql->where(\%where);
2145 However, note that the C<%where> hash can be used directly in any
2146 of the other functions as well, as described above.
2148 =head2 Key-value pairs
2150 So, let's get started. To begin, a simple hash:
2154 status => 'completed'
2157 Is converted to SQL C<key = val> statements:
2159 $stmt = "WHERE user = ? AND status = ?";
2160 @bind = ('nwiger', 'completed');
2162 One common thing I end up doing is having a list of values that
2163 a field can be in. To do this, simply specify a list inside of
2168 status => ['assigned', 'in-progress', 'pending'];
2171 This simple code will create the following:
2173 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2174 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2176 A field associated to an empty arrayref will be considered a
2177 logical false and will generate 0=1.
2179 =head2 Tests for NULL values
2181 If the value part is C<undef> then this is converted to SQL <IS NULL>
2190 $stmt = "WHERE user = ? AND status IS NULL";
2193 To test if a column IS NOT NULL:
2197 status => { '!=', undef },
2200 =head2 Specific comparison operators
2202 If you want to specify a different type of operator for your comparison,
2203 you can use a hashref for a given column:
2207 status => { '!=', 'completed' }
2210 Which would generate:
2212 $stmt = "WHERE user = ? AND status != ?";
2213 @bind = ('nwiger', 'completed');
2215 To test against multiple values, just enclose the values in an arrayref:
2217 status => { '=', ['assigned', 'in-progress', 'pending'] };
2219 Which would give you:
2221 "WHERE status = ? OR status = ? OR status = ?"
2224 The hashref can also contain multiple pairs, in which case it is expanded
2225 into an C<AND> of its elements:
2229 status => { '!=', 'completed', -not_like => 'pending%' }
2232 # Or more dynamically, like from a form
2233 $where{user} = 'nwiger';
2234 $where{status}{'!='} = 'completed';
2235 $where{status}{'-not_like'} = 'pending%';
2237 # Both generate this
2238 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2239 @bind = ('nwiger', 'completed', 'pending%');
2242 To get an OR instead, you can combine it with the arrayref idea:
2246 priority => [ { '=', 2 }, { '>', 5 } ]
2249 Which would generate:
2251 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2252 @bind = ('2', '5', 'nwiger');
2254 If you want to include literal SQL (with or without bind values), just use a
2255 scalar reference or reference to an arrayref as the value:
2258 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2259 date_expires => { '<' => \"now()" }
2262 Which would generate:
2264 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2265 @bind = ('11/26/2008');
2268 =head2 Logic and nesting operators
2270 In the example above,
2271 there is a subtle trap if you want to say something like
2272 this (notice the C<AND>):
2274 WHERE priority != ? AND priority != ?
2276 Because, in Perl you I<can't> do this:
2278 priority => { '!=' => 2, '!=' => 1 }
2280 As the second C<!=> key will obliterate the first. The solution
2281 is to use the special C<-modifier> form inside an arrayref:
2283 priority => [ -and => {'!=', 2},
2287 Normally, these would be joined by C<OR>, but the modifier tells it
2288 to use C<AND> instead. (Hint: You can use this in conjunction with the
2289 C<logic> option to C<new()> in order to change the way your queries
2290 work by default.) B<Important:> Note that the C<-modifier> goes
2291 B<INSIDE> the arrayref, as an extra first element. This will
2292 B<NOT> do what you think it might:
2294 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2296 Here is a quick list of equivalencies, since there is some overlap:
2299 status => {'!=', 'completed', 'not like', 'pending%' }
2300 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2303 status => {'=', ['assigned', 'in-progress']}
2304 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2305 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2309 =head2 Special operators: IN, BETWEEN, etc.
2311 You can also use the hashref format to compare a list of fields using the
2312 C<IN> comparison operator, by specifying the list as an arrayref:
2315 status => 'completed',
2316 reportid => { -in => [567, 2335, 2] }
2319 Which would generate:
2321 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2322 @bind = ('completed', '567', '2335', '2');
2324 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2327 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2328 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2329 'sqltrue' (by default: C<1=1>).
2331 In addition to the array you can supply a chunk of literal sql or
2332 literal sql with bind:
2335 customer => { -in => \[
2336 'SELECT cust_id FROM cust WHERE balance > ?',
2339 status => { -in => \'SELECT status_codes FROM states' },
2345 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2346 AND status IN ( SELECT status_codes FROM states )
2350 Finally, if the argument to C<-in> is not a reference, it will be
2351 treated as a single-element array.
2353 Another pair of operators is C<-between> and C<-not_between>,
2354 used with an arrayref of two values:
2358 completion_date => {
2359 -not_between => ['2002-10-01', '2003-02-06']
2365 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2367 Just like with C<-in> all plausible combinations of literal SQL
2371 start0 => { -between => [ 1, 2 ] },
2372 start1 => { -between => \["? AND ?", 1, 2] },
2373 start2 => { -between => \"lower(x) AND upper(y)" },
2374 start3 => { -between => [
2376 \["upper(?)", 'stuff' ],
2383 ( start0 BETWEEN ? AND ? )
2384 AND ( start1 BETWEEN ? AND ? )
2385 AND ( start2 BETWEEN lower(x) AND upper(y) )
2386 AND ( start3 BETWEEN lower(x) AND upper(?) )
2388 @bind = (1, 2, 1, 2, 'stuff');
2391 These are the two builtin "special operators"; but the
2392 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2394 =head2 Unary operators: bool
2396 If you wish to test against boolean columns or functions within your
2397 database you can use the C<-bool> and C<-not_bool> operators. For
2398 example to test the column C<is_user> being true and the column
2399 C<is_enabled> being false you would use:-
2403 -not_bool => 'is_enabled',
2408 WHERE is_user AND NOT is_enabled
2410 If a more complex combination is required, testing more conditions,
2411 then you should use the and/or operators:-
2416 -not_bool => { two=> { -rlike => 'bar' } },
2417 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2428 (NOT ( three = ? OR three > ? ))
2431 =head2 Nested conditions, -and/-or prefixes
2433 So far, we've seen how multiple conditions are joined with a top-level
2434 C<AND>. We can change this by putting the different conditions we want in
2435 hashes and then putting those hashes in an array. For example:
2440 status => { -like => ['pending%', 'dispatched'] },
2444 status => 'unassigned',
2448 This data structure would create the following:
2450 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2451 OR ( user = ? AND status = ? ) )";
2452 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2455 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2456 to change the logic inside:
2462 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2463 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2470 $stmt = "WHERE ( user = ?
2471 AND ( ( workhrs > ? AND geo = ? )
2472 OR ( workhrs < ? OR geo = ? ) ) )";
2473 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2475 =head3 Algebraic inconsistency, for historical reasons
2477 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2478 operator goes C<outside> of the nested structure; whereas when connecting
2479 several constraints on one column, the C<-and> operator goes
2480 C<inside> the arrayref. Here is an example combining both features:
2483 -and => [a => 1, b => 2],
2484 -or => [c => 3, d => 4],
2485 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2490 WHERE ( ( ( a = ? AND b = ? )
2491 OR ( c = ? OR d = ? )
2492 OR ( e LIKE ? AND e LIKE ? ) ) )
2494 This difference in syntax is unfortunate but must be preserved for
2495 historical reasons. So be careful: the two examples below would
2496 seem algebraically equivalent, but they are not
2499 { -like => 'foo%' },
2500 { -like => '%bar' },
2502 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2505 { col => { -like => 'foo%' } },
2506 { col => { -like => '%bar' } },
2508 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2511 =head2 Literal SQL and value type operators
2513 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2514 side" is a column name and the "right side" is a value (normally rendered as
2515 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2516 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2517 alter this behavior. There are several ways of doing so.
2521 This is a virtual operator that signals the string to its right side is an
2522 identifier (a column name) and not a value. For example to compare two
2523 columns you would write:
2526 priority => { '<', 2 },
2527 requestor => { -ident => 'submitter' },
2532 $stmt = "WHERE priority < ? AND requestor = submitter";
2535 If you are maintaining legacy code you may see a different construct as
2536 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2541 This is a virtual operator that signals that the construct to its right side
2542 is a value to be passed to DBI. This is for example necessary when you want
2543 to write a where clause against an array (for RDBMS that support such
2544 datatypes). For example:
2547 array => { -value => [1, 2, 3] }
2552 $stmt = 'WHERE array = ?';
2553 @bind = ([1, 2, 3]);
2555 Note that if you were to simply say:
2561 the result would probably not be what you wanted:
2563 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2568 Finally, sometimes only literal SQL will do. To include a random snippet
2569 of SQL verbatim, you specify it as a scalar reference. Consider this only
2570 as a last resort. Usually there is a better way. For example:
2573 priority => { '<', 2 },
2574 requestor => { -in => \'(SELECT name FROM hitmen)' },
2579 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2582 Note that in this example, you only get one bind parameter back, since
2583 the verbatim SQL is passed as part of the statement.
2587 Never use untrusted input as a literal SQL argument - this is a massive
2588 security risk (there is no way to check literal snippets for SQL
2589 injections and other nastyness). If you need to deal with untrusted input
2590 use literal SQL with placeholders as described next.
2592 =head3 Literal SQL with placeholders and bind values (subqueries)
2594 If the literal SQL to be inserted has placeholders and bind values,
2595 use a reference to an arrayref (yes this is a double reference --
2596 not so common, but perfectly legal Perl). For example, to find a date
2597 in Postgres you can use something like this:
2600 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2605 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2608 Note that you must pass the bind values in the same format as they are returned
2609 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2610 to C<columns>, you must provide the bind values in the
2611 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2612 scalar value; most commonly the column name, but you can use any scalar value
2613 (including references and blessed references), L<SQL::Abstract> will simply
2614 pass it through intact. So if C<bindtype> is set to C<columns> the above
2615 example will look like:
2618 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2621 Literal SQL is especially useful for nesting parenthesized clauses in the
2622 main SQL query. Here is a first example:
2624 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2628 bar => \["IN ($sub_stmt)" => @sub_bind],
2633 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2634 WHERE c2 < ? AND c3 LIKE ?))";
2635 @bind = (1234, 100, "foo%");
2637 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2638 are expressed in the same way. Of course the C<$sub_stmt> and
2639 its associated bind values can be generated through a former call
2642 my ($sub_stmt, @sub_bind)
2643 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2644 c3 => {-like => "foo%"}});
2647 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2650 In the examples above, the subquery was used as an operator on a column;
2651 but the same principle also applies for a clause within the main C<%where>
2652 hash, like an EXISTS subquery:
2654 my ($sub_stmt, @sub_bind)
2655 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2656 my %where = ( -and => [
2658 \["EXISTS ($sub_stmt)" => @sub_bind],
2663 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2664 WHERE c1 = ? AND c2 > t0.c0))";
2668 Observe that the condition on C<c2> in the subquery refers to
2669 column C<t0.c0> of the main query: this is I<not> a bind
2670 value, so we have to express it through a scalar ref.
2671 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2672 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2673 what we wanted here.
2675 Finally, here is an example where a subquery is used
2676 for expressing unary negation:
2678 my ($sub_stmt, @sub_bind)
2679 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2680 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2682 lname => {like => '%son%'},
2683 \["NOT ($sub_stmt)" => @sub_bind],
2688 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2689 @bind = ('%son%', 10, 20)
2691 =head3 Deprecated usage of Literal SQL
2693 Below are some examples of archaic use of literal SQL. It is shown only as
2694 reference for those who deal with legacy code. Each example has a much
2695 better, cleaner and safer alternative that users should opt for in new code.
2701 my %where = ( requestor => \'IS NOT NULL' )
2703 $stmt = "WHERE requestor IS NOT NULL"
2705 This used to be the way of generating NULL comparisons, before the handling
2706 of C<undef> got formalized. For new code please use the superior syntax as
2707 described in L</Tests for NULL values>.
2711 my %where = ( requestor => \'= submitter' )
2713 $stmt = "WHERE requestor = submitter"
2715 This used to be the only way to compare columns. Use the superior L</-ident>
2716 method for all new code. For example an identifier declared in such a way
2717 will be properly quoted if L</quote_char> is properly set, while the legacy
2718 form will remain as supplied.
2722 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2724 $stmt = "WHERE completed > ? AND is_ready"
2725 @bind = ('2012-12-21')
2727 Using an empty string literal used to be the only way to express a boolean.
2728 For all new code please use the much more readable
2729 L<-bool|/Unary operators: bool> operator.
2735 These pages could go on for a while, since the nesting of the data
2736 structures this module can handle are pretty much unlimited (the
2737 module implements the C<WHERE> expansion as a recursive function
2738 internally). Your best bet is to "play around" with the module a
2739 little to see how the data structures behave, and choose the best
2740 format for your data based on that.
2742 And of course, all the values above will probably be replaced with
2743 variables gotten from forms or the command line. After all, if you
2744 knew everything ahead of time, you wouldn't have to worry about
2745 dynamically-generating SQL and could just hardwire it into your
2748 =head1 ORDER BY CLAUSES
2750 Some functions take an order by clause. This can either be a scalar (just a
2751 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2752 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2755 Given | Will Generate
2756 ---------------------------------------------------------------
2758 'colA' | ORDER BY colA
2760 [qw/colA colB/] | ORDER BY colA, colB
2762 {-asc => 'colA'} | ORDER BY colA ASC
2764 {-desc => 'colB'} | ORDER BY colB DESC
2766 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2768 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2770 \'colA DESC' | ORDER BY colA DESC
2772 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2773 | /* ...with $x bound to ? */
2776 { -asc => 'colA' }, | colA ASC,
2777 { -desc => [qw/colB/] }, | colB DESC,
2778 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2779 \'colE DESC', | colE DESC,
2780 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2781 ] | /* ...with $x bound to ? */
2782 ===============================================================
2786 =head1 SPECIAL OPERATORS
2788 my $sqlmaker = SQL::Abstract->new(special_ops => [
2792 my ($self, $field, $op, $arg) = @_;
2798 handler => 'method_name',
2802 A "special operator" is a SQL syntactic clause that can be
2803 applied to a field, instead of a usual binary operator.
2806 WHERE field IN (?, ?, ?)
2807 WHERE field BETWEEN ? AND ?
2808 WHERE MATCH(field) AGAINST (?, ?)
2810 Special operators IN and BETWEEN are fairly standard and therefore
2811 are builtin within C<SQL::Abstract> (as the overridable methods
2812 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2813 like the MATCH .. AGAINST example above which is specific to MySQL,
2814 you can write your own operator handlers - supply a C<special_ops>
2815 argument to the C<new> method. That argument takes an arrayref of
2816 operator definitions; each operator definition is a hashref with two
2823 the regular expression to match the operator
2827 Either a coderef or a plain scalar method name. In both cases
2828 the expected return is C<< ($sql, @bind) >>.
2830 When supplied with a method name, it is simply called on the
2831 L<SQL::Abstract> object as:
2833 $self->$method_name($field, $op, $arg)
2837 $field is the LHS of the operator
2838 $op is the part that matched the handler regex
2841 When supplied with a coderef, it is called as:
2843 $coderef->($self, $field, $op, $arg)
2848 For example, here is an implementation
2849 of the MATCH .. AGAINST syntax for MySQL
2851 my $sqlmaker = SQL::Abstract->new(special_ops => [
2853 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2854 {regex => qr/^match$/i,
2856 my ($self, $field, $op, $arg) = @_;
2857 $arg = [$arg] if not ref $arg;
2858 my $label = $self->_quote($field);
2859 my ($placeholder) = $self->_convert('?');
2860 my $placeholders = join ", ", (($placeholder) x @$arg);
2861 my $sql = $self->_sqlcase('match') . " ($label) "
2862 . $self->_sqlcase('against') . " ($placeholders) ";
2863 my @bind = $self->_bindtype($field, @$arg);
2864 return ($sql, @bind);
2871 =head1 UNARY OPERATORS
2873 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2877 my ($self, $op, $arg) = @_;
2883 handler => 'method_name',
2887 A "unary operator" is a SQL syntactic clause that can be
2888 applied to a field - the operator goes before the field
2890 You can write your own operator handlers - supply a C<unary_ops>
2891 argument to the C<new> method. That argument takes an arrayref of
2892 operator definitions; each operator definition is a hashref with two
2899 the regular expression to match the operator
2903 Either a coderef or a plain scalar method name. In both cases
2904 the expected return is C<< $sql >>.
2906 When supplied with a method name, it is simply called on the
2907 L<SQL::Abstract> object as:
2909 $self->$method_name($op, $arg)
2913 $op is the part that matched the handler regex
2914 $arg is the RHS or argument of the operator
2916 When supplied with a coderef, it is called as:
2918 $coderef->($self, $op, $arg)
2926 Thanks to some benchmarking by Mark Stosberg, it turns out that
2927 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2928 I must admit this wasn't an intentional design issue, but it's a
2929 byproduct of the fact that you get to control your C<DBI> handles
2932 To maximize performance, use a code snippet like the following:
2934 # prepare a statement handle using the first row
2935 # and then reuse it for the rest of the rows
2937 for my $href (@array_of_hashrefs) {
2938 $stmt ||= $sql->insert('table', $href);
2939 $sth ||= $dbh->prepare($stmt);
2940 $sth->execute($sql->values($href));
2943 The reason this works is because the keys in your C<$href> are sorted
2944 internally by B<SQL::Abstract>. Thus, as long as your data retains
2945 the same structure, you only have to generate the SQL the first time
2946 around. On subsequent queries, simply use the C<values> function provided
2947 by this module to return your values in the correct order.
2949 However this depends on the values having the same type - if, for
2950 example, the values of a where clause may either have values
2951 (resulting in sql of the form C<column = ?> with a single bind
2952 value), or alternatively the values might be C<undef> (resulting in
2953 sql of the form C<column IS NULL> with no bind value) then the
2954 caching technique suggested will not work.
2958 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2959 really like this part (I do, at least). Building up a complex query
2960 can be as simple as the following:
2967 use CGI::FormBuilder;
2970 my $form = CGI::FormBuilder->new(...);
2971 my $sql = SQL::Abstract->new;
2973 if ($form->submitted) {
2974 my $field = $form->field;
2975 my $id = delete $field->{id};
2976 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2979 Of course, you would still have to connect using C<DBI> to run the
2980 query, but the point is that if you make your form look like your
2981 table, the actual query script can be extremely simplistic.
2983 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2984 a fast interface to returning and formatting data. I frequently
2985 use these three modules together to write complex database query
2986 apps in under 50 lines.
2988 =head1 HOW TO CONTRIBUTE
2990 Contributions are always welcome, in all usable forms (we especially
2991 welcome documentation improvements). The delivery methods include git-
2992 or unified-diff formatted patches, GitHub pull requests, or plain bug
2993 reports either via RT or the Mailing list. Contributors are generally
2994 granted full access to the official repository after their first several
2995 patches pass successful review.
2997 This project is maintained in a git repository. The code and related tools are
2998 accessible at the following locations:
3002 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3004 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3006 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3008 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3014 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3015 Great care has been taken to preserve the I<published> behavior
3016 documented in previous versions in the 1.* family; however,
3017 some features that were previously undocumented, or behaved
3018 differently from the documentation, had to be changed in order
3019 to clarify the semantics. Hence, client code that was relying
3020 on some dark areas of C<SQL::Abstract> v1.*
3021 B<might behave differently> in v1.50.
3023 The main changes are:
3029 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3033 support for the { operator => \"..." } construct (to embed literal SQL)
3037 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3041 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3045 defensive programming: check arguments
3049 fixed bug with global logic, which was previously implemented
3050 through global variables yielding side-effects. Prior versions would
3051 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3052 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3053 Now this is interpreted
3054 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3059 fixed semantics of _bindtype on array args
3063 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3064 we just avoid shifting arrays within that tree.
3068 dropped the C<_modlogic> function
3072 =head1 ACKNOWLEDGEMENTS
3074 There are a number of individuals that have really helped out with
3075 this module. Unfortunately, most of them submitted bugs via CPAN
3076 so I have no idea who they are! But the people I do know are:
3078 Ash Berlin (order_by hash term support)
3079 Matt Trout (DBIx::Class support)
3080 Mark Stosberg (benchmarking)
3081 Chas Owens (initial "IN" operator support)
3082 Philip Collins (per-field SQL functions)
3083 Eric Kolve (hashref "AND" support)
3084 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3085 Dan Kubb (support for "quote_char" and "name_sep")
3086 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3087 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3088 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3089 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3090 Oliver Charles (support for "RETURNING" after "INSERT")
3096 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3100 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3102 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3104 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3105 While not an official support venue, C<DBIx::Class> makes heavy use of
3106 C<SQL::Abstract>, and as such list members there are very familiar with
3107 how to create queries.
3111 This module is free software; you may copy this under the same
3112 terms as perl itself (either the GNU General Public License or
3113 the Artistic License)