1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
164 $opt{unary_ops} ||= [];
166 # rudimentary sanity-check for user supplied bits treated as functions/operators
167 # If a purported function matches this regular expression, an exception is thrown.
168 # Literal SQL is *NOT* subject to this check, only functions (and column names
169 # when quoting is not in effect)
172 # need to guard against ()'s in column names too, but this will break tons of
173 # hacks... ideas anyone?
174 $opt{injection_guard} ||= qr/
180 $opt{node_types} = +{
181 map +("-$_" => '_render_'.$_),
182 qw(op func value bind ident literal)
185 $opt{expand_unary} = {};
187 return bless \%opt, $class;
190 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
191 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
193 sub _assert_pass_injection_guard {
194 if ($_[1] =~ $_[0]->{injection_guard}) {
195 my $class = ref $_[0];
196 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
197 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
198 . "{injection_guard} attribute to ${class}->new()"
203 #======================================================================
205 #======================================================================
209 my $table = $self->_table(shift);
210 my $data = shift || return;
213 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
214 my ($sql, @bind) = $self->$method($data);
215 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
217 if ($options->{returning}) {
218 my ($s, @b) = $self->_insert_returning($options);
223 return wantarray ? ($sql, @bind) : $sql;
226 # So that subclasses can override INSERT ... RETURNING separately from
227 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
228 sub _insert_returning { shift->_returning(@_) }
231 my ($self, $options) = @_;
233 my $f = $options->{returning};
235 my ($sql, @bind) = $self->_render_expr(
236 $self->_expand_maybe_list_expr($f, undef, -ident)
239 ? $self->_sqlcase(' returning ') . $sql
240 : ($self->_sqlcase(' returning ').$sql, @bind);
243 sub _insert_HASHREF { # explicit list of fields and then values
244 my ($self, $data) = @_;
246 my @fields = sort keys %$data;
248 my ($sql, @bind) = $self->_insert_values($data);
251 $_ = $self->_quote($_) foreach @fields;
252 $sql = "( ".join(", ", @fields).") ".$sql;
254 return ($sql, @bind);
257 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
258 my ($self, $data) = @_;
260 # no names (arrayref) so can't generate bindtype
261 $self->{bindtype} ne 'columns'
262 or belch "can't do 'columns' bindtype when called with arrayref";
264 my (@values, @all_bind);
265 foreach my $value (@$data) {
266 my ($values, @bind) = $self->_insert_value(undef, $value);
267 push @values, $values;
268 push @all_bind, @bind;
270 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
271 return ($sql, @all_bind);
274 sub _insert_ARRAYREFREF { # literal SQL with bind
275 my ($self, $data) = @_;
277 my ($sql, @bind) = @${$data};
278 $self->_assert_bindval_matches_bindtype(@bind);
280 return ($sql, @bind);
284 sub _insert_SCALARREF { # literal SQL without bind
285 my ($self, $data) = @_;
291 my ($self, $data) = @_;
293 my (@values, @all_bind);
294 foreach my $column (sort keys %$data) {
295 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
296 push @values, $values;
297 push @all_bind, @bind;
299 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
300 return ($sql, @all_bind);
304 my ($self, $column, $v) = @_;
306 return $self->_render_expr(
307 $self->_expand_insert_value($column, $v)
311 sub _expand_insert_value {
312 my ($self, $column, $v) = @_;
314 if (ref($v) eq 'ARRAY') {
315 if ($self->{array_datatypes}) {
316 return +{ -bind => [ $column, $v ] };
318 my ($sql, @bind) = @$v;
319 $self->_assert_bindval_matches_bindtype(@bind);
320 return +{ -literal => $v };
322 if (ref($v) eq 'HASH') {
323 if (grep !/^-/, keys %$v) {
324 belch "HASH ref as bind value in insert is not supported";
325 return +{ -bind => [ $column, $v ] };
329 return +{ -bind => [ $column, undef ] };
331 local our $Cur_Col_Meta = $column;
332 return $self->_expand_expr($v);
337 #======================================================================
339 #======================================================================
344 my $table = $self->_table(shift);
345 my $data = shift || return;
349 # first build the 'SET' part of the sql statement
350 puke "Unsupported data type specified to \$sql->update"
351 unless ref $data eq 'HASH';
353 my ($sql, @all_bind) = $self->_update_set_values($data);
354 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
358 my($where_sql, @where_bind) = $self->where($where);
360 push @all_bind, @where_bind;
363 if ($options->{returning}) {
364 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
365 $sql .= $returning_sql;
366 push @all_bind, @returning_bind;
369 return wantarray ? ($sql, @all_bind) : $sql;
372 sub _update_set_values {
373 my ($self, $data) = @_;
375 return $self->_render_expr(
376 $self->_expand_update_set_values($data),
380 sub _expand_update_set_values {
381 my ($self, $data) = @_;
382 $self->_expand_maybe_list_expr( [
385 $set = { -bind => $_ } unless defined $set;
386 +{ -op => [ '=', { -ident => $k }, $set ] };
392 ? ($self->{array_datatypes}
393 ? [ $k, +{ -bind => [ $k, $v ] } ]
394 : [ $k, +{ -literal => $v } ])
396 local our $Cur_Col_Meta = $k;
397 [ $k, $self->_expand_expr($v) ]
404 # So that subclasses can override UPDATE ... RETURNING separately from
406 sub _update_returning { shift->_returning(@_) }
410 #======================================================================
412 #======================================================================
417 my $table = $self->_table(shift);
418 my $fields = shift || '*';
422 my ($fields_sql, @bind) = $self->_select_fields($fields);
424 my ($where_sql, @where_bind) = $self->where($where, $order);
425 push @bind, @where_bind;
427 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
428 $self->_sqlcase('from'), $table)
431 return wantarray ? ($sql, @bind) : $sql;
435 my ($self, $fields) = @_;
436 return $fields unless ref($fields);
437 return $self->_render_expr(
438 $self->_expand_maybe_list_expr($fields, undef, '-ident')
442 #======================================================================
444 #======================================================================
449 my $table = $self->_table(shift);
453 my($where_sql, @bind) = $self->where($where);
454 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
456 if ($options->{returning}) {
457 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
458 $sql .= $returning_sql;
459 push @bind, @returning_bind;
462 return wantarray ? ($sql, @bind) : $sql;
465 # So that subclasses can override DELETE ... RETURNING separately from
467 sub _delete_returning { shift->_returning(@_) }
471 #======================================================================
473 #======================================================================
477 # Finally, a separate routine just to handle WHERE clauses
479 my ($self, $where, $order) = @_;
481 local $self->{convert_where} = $self->{convert};
484 my ($sql, @bind) = defined($where)
485 ? $self->_recurse_where($where)
487 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
491 my ($order_sql, @order_bind) = $self->_order_by($order);
493 push @bind, @order_bind;
496 return wantarray ? ($sql, @bind) : $sql;
500 my ($self, $expr, $logic, $default_scalar_to) = @_;
501 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
502 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
503 return undef unless defined($expr);
504 if (ref($expr) eq 'HASH') {
505 if (keys %$expr > 1) {
509 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
513 return unless %$expr;
514 return $self->_expand_expr_hashpair(%$expr, $logic);
516 if (ref($expr) eq 'ARRAY') {
517 my $logic = lc($logic || $self->{logic});
518 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
524 while (my ($el) = splice @expr, 0, 1) {
525 puke "Supplying an empty left hand side argument is not supported in array-pairs"
526 unless defined($el) and length($el);
527 my $elref = ref($el);
529 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
530 } elsif ($elref eq 'ARRAY') {
531 push(@res, $self->_expand_expr($el)) if @$el;
532 } elsif (my $l = is_literal_value($el)) {
533 push @res, { -literal => $l };
534 } elsif ($elref eq 'HASH') {
535 push @res, $self->_expand_expr($el);
540 return { -op => [ $logic, @res ] };
542 if (my $literal = is_literal_value($expr)) {
543 return +{ -literal => $literal };
545 if (!ref($expr) or Scalar::Util::blessed($expr)) {
546 if (my $d = $Default_Scalar_To) {
547 return +{ $d => $expr };
549 if (my $m = our $Cur_Col_Meta) {
550 return +{ -bind => [ $m, $expr ] };
552 return +{ -value => $expr };
559 sub _expand_expr_hashpair {
560 my ($self, $k, $v, $logic) = @_;
561 unless (defined($k) and length($k)) {
562 if (defined($k) and my $literal = is_literal_value($v)) {
563 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
564 return { -literal => $literal };
566 puke "Supplying an empty left hand side argument is not supported";
569 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
570 if ($k =~ s/ [_\s]? \d+ $//x ) {
571 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
572 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
575 # DBIx::Class requires a nest warning to be emitted once but the private
576 # method it overrode to do so no longer exists
577 if (ref($self) =~ /^DBIx::Class::SQLMaker/) {
578 unless ($Nest_Warned) {
580 "-nest in search conditions is deprecated, you most probably wanted:\n"
581 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
586 return $self->_expand_expr($v);
590 return $self->_expand_expr($v);
592 puke "-bool => undef not supported" unless defined($v);
593 return { -ident => $v };
596 return { -op => [ 'not', $self->_expand_expr($v) ] };
598 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
601 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
604 if (my ($logic) = $k =~ /^-(and|or)$/i) {
605 if (ref($v) eq 'HASH') {
606 return $self->_expand_expr($v, $logic);
608 if (ref($v) eq 'ARRAY') {
609 return $self->_expand_expr($v, $logic);
614 $op =~ s/^-// if length($op) > 1;
616 # top level special ops are illegal in general
617 # note that, arguably, if it makes no sense at top level, it also
618 # makes no sense on the other side of an = sign or similar but DBIC
619 # gets disappointingly upset if I disallow it
621 (our $Expand_Depth) == 1
622 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
624 puke "Illegal use of top-level '-$op'"
626 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
627 return { -op => [ $op, $v ] };
630 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
631 return +{ -bind => [ $m, $v ] };
633 if (my $custom = $self->{expand_unary}{$k}) {
634 return $self->$custom($v);
636 if ($self->{node_types}{$k}) {
642 and (keys %$v)[0] =~ /^-/
644 my ($func) = $k =~ /^-(.*)$/;
645 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
646 return +{ -op => [ $func, $self->_expand_expr($v) ] };
648 return +{ -func => [ $func, $self->_expand_expr($v) ] };
650 if (!ref($v) or is_literal_value($v)) {
651 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
658 and exists $v->{-value}
659 and not defined $v->{-value}
662 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
664 if (!ref($v) or Scalar::Util::blessed($v)) {
665 my $d = our $Default_Scalar_To;
670 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
674 if (ref($v) eq 'HASH') {
678 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
685 $self->_assert_pass_injection_guard($vk);
686 if ($vk =~ s/ [_\s]? \d+ $//x ) {
687 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
688 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
690 if ($vk =~ /^(?:not[ _])?between$/) {
691 local our $Cur_Col_Meta = $k;
692 my @rhs = map $self->_expand_expr($_),
693 ref($vv) eq 'ARRAY' ? @$vv : $vv;
695 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
697 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
699 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
702 join(' ', split '_', $vk),
707 if ($vk =~ /^(?:not[ _])?in$/) {
708 if (my $literal = is_literal_value($vv)) {
709 my ($sql, @bind) = @$literal;
710 my $opened_sql = $self->_open_outer_paren($sql);
712 $vk, { -ident => $k },
713 [ { -literal => [ $opened_sql, @bind ] } ]
717 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
718 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
719 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
720 . 'will emit the logically correct SQL instead of raising this exception)'
722 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
724 my @rhs = map $self->_expand_expr($_),
725 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
726 map { defined($_) ? $_: puke($undef_err) }
727 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
728 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
731 join(' ', split '_', $vk),
736 if ($vk eq 'ident') {
737 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
738 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
746 if ($vk eq 'value') {
747 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
751 { -bind => [ $k, $vv ] }
754 if ($vk =~ /^is(?:[ _]not)?$/) {
755 puke "$vk can only take undef as argument"
759 and exists($vv->{-value})
760 and !defined($vv->{-value})
763 return +{ -op => [ $vk.' null', { -ident => $k } ] };
765 if ($vk =~ /^(and|or)$/) {
766 if (ref($vv) eq 'HASH') {
769 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
774 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
775 return { -op => [ $vk, { -ident => $k }, $vv ] };
777 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
781 { -op => [ $vk, $vv ] }
784 if (ref($vv) eq 'ARRAY') {
785 my ($logic, @values) = (
786 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
791 $vk =~ $self->{inequality_op}
792 or join(' ', split '_', $vk) =~ $self->{not_like_op}
794 if (lc($logic) eq '-or' and @values > 1) {
795 my $op = uc join ' ', split '_', $vk;
796 belch "A multi-element arrayref as an argument to the inequality op '$op' "
797 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
798 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
803 # try to DWIM on equality operators
804 my $op = join ' ', split '_', $vk;
806 $op =~ $self->{equality_op} ? $self->sqlfalse
807 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
808 : $op =~ $self->{inequality_op} ? $self->sqltrue
809 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
810 : puke "operator '$op' applied on an empty array (field '$k')";
814 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
822 and exists $vv->{-value}
823 and not defined $vv->{-value}
826 my $op = join ' ', split '_', $vk;
828 $op =~ /^not$/i ? 'is not' # legacy
829 : $op =~ $self->{equality_op} ? 'is'
830 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
831 : $op =~ $self->{inequality_op} ? 'is not'
832 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
833 : puke "unexpected operator '$op' with undef operand";
834 return +{ -op => [ $is.' null', { -ident => $k } ] };
836 local our $Cur_Col_Meta = $k;
840 $self->_expand_expr($vv)
843 if (ref($v) eq 'ARRAY') {
844 return $self->sqlfalse unless @$v;
845 $self->_debug("ARRAY($k) means distribute over elements");
847 $v->[0] =~ /^-((?:and|or))$/i
848 ? ($v = [ @{$v}[1..$#$v] ], $1)
849 : ($self->{logic} || 'or')
853 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
856 if (my $literal = is_literal_value($v)) {
858 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
861 my ($sql, @bind) = @$literal;
862 if ($self->{bindtype} eq 'columns') {
864 $self->_assert_bindval_matches_bindtype($_);
867 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
873 my ($self, $expr) = @_;
874 my ($k, $v, @rest) = %$expr;
876 if (my $meth = $self->{node_types}{$k}) {
877 return $self->$meth($v);
879 die "notreached: $k";
883 my ($self, $where, $logic) = @_;
885 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
887 # Special case: top level simple string treated as literal
889 my $where_exp = (ref($where)
890 ? $self->_expand_expr($where, $logic)
891 : { -literal => [ $where ] });
893 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
895 # dispatch on appropriate method according to refkind of $where
896 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
898 # my ($sql, @bind) = $self->$method($where_exp, $logic);
900 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
902 # DBIx::Class used to call _recurse_where in scalar context
903 # something else might too...
905 return ($sql, @bind);
908 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
914 my ($self, $ident) = @_;
916 return $self->_convert($self->_quote($ident));
920 my ($self, $value) = @_;
922 return ($self->_convert('?'), $self->_bindtype(undef, $value));
925 my %unop_postfix = map +($_ => 1),
926 'is null', 'is not null',
934 my ($self, $args) = @_;
935 my ($left, $low, $high) = @$args;
936 my ($rhsql, @rhbind) = do {
938 puke "Single arg to between must be a literal"
939 unless $low->{-literal};
942 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
943 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
944 @{$l}[1..$#$l], @{$h}[1..$#$h])
947 my ($lhsql, @lhbind) = $self->_render_expr($left);
949 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
953 }), 'between', 'not between'),
957 my ($self, $args) = @_;
958 my ($lhs, $rhs) = @$args;
961 my ($sql, @bind) = $self->_render_expr($_);
962 push @in_bind, @bind;
965 my ($lhsql, @lbind) = $self->_render_expr($lhs);
967 $lhsql.' '.$self->_sqlcase($op).' ( '
978 my ($op, @args) = @$v;
979 $op =~ s/^-// if length($op) > 1;
981 if (my $h = $special{$op}) {
982 return $self->$h(\@args);
984 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
985 if ($us and @args > 1) {
986 puke "Special op '${op}' requires first value to be identifier"
987 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
988 return $self->${\($us->{handler})}($k, $op, $args[1]);
990 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
991 return $self->${\($us->{handler})}($op, $args[0]);
993 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
994 if (@args == 1 and $op !~ /^(and|or)$/) {
995 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
996 my $op_sql = $self->_sqlcase($final_op);
998 $unop_postfix{lc($final_op)}
999 ? "${expr_sql} ${op_sql}"
1000 : "${op_sql} ${expr_sql}"
1002 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1004 my @parts = map [ $self->_render_expr($_) ], @args;
1005 my $is_andor = !!($op =~ /^(and|or)$/);
1006 return @{$parts[0]} if $is_andor and @parts == 1;
1007 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1008 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
1013 map @{$_}[1..$#$_], @parts
1020 my ($self, $rest) = @_;
1021 my ($func, @args) = @$rest;
1025 push @arg_sql, shift @x;
1027 } map [ $self->_render_expr($_) ], @args;
1028 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1032 my ($self, $bind) = @_;
1033 return ($self->_convert('?'), $self->_bindtype(@$bind));
1036 sub _render_literal {
1037 my ($self, $literal) = @_;
1038 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1042 # Some databases (SQLite) treat col IN (1, 2) different from
1043 # col IN ( (1, 2) ). Use this to strip all outer parens while
1044 # adding them back in the corresponding method
1045 sub _open_outer_paren {
1046 my ($self, $sql) = @_;
1048 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1050 # there are closing parens inside, need the heavy duty machinery
1051 # to reevaluate the extraction starting from $sql (full reevaluation)
1052 if ($inner =~ /\)/) {
1053 require Text::Balanced;
1055 my (undef, $remainder) = do {
1056 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1058 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1061 # the entire expression needs to be a balanced bracketed thing
1062 # (after an extract no remainder sans trailing space)
1063 last if defined $remainder and $remainder =~ /\S/;
1073 #======================================================================
1075 #======================================================================
1077 sub _expand_order_by {
1078 my ($self, $arg) = @_;
1080 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1082 my $expander = sub {
1083 my ($self, $dir, $expr) = @_;
1084 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1085 foreach my $arg (@to_expand) {
1089 and grep /^-(asc|desc)$/, keys %$arg
1091 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1094 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1095 map $self->_expand_expr($_, undef, -ident),
1096 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1097 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1100 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1101 sub { shift->$expander(asc => @_) },
1102 sub { shift->$expander(desc => @_) },
1105 return $self->$expander(undef, $arg);
1109 my ($self, $arg) = @_;
1111 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1113 my ($sql, @bind) = $self->_render_expr($expanded);
1115 my $final_sql = $self->_sqlcase(' order by ').$sql;
1117 return wantarray ? ($final_sql, @bind) : $final_sql;
1120 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1122 sub _order_by_chunks {
1123 my ($self, $arg) = @_;
1125 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1127 return $self->_chunkify_order_by($expanded);
1130 sub _chunkify_order_by {
1131 my ($self, $expanded) = @_;
1133 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1134 if ($op->[0] eq ',') {
1135 return map $self->_chunkify_order_by($_), @{$op}[1..$#$op];
1138 return [ $self->_render_expr($_) ];
1142 #======================================================================
1143 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1144 #======================================================================
1149 ($self->_render_expr(
1150 $self->_expand_maybe_list_expr($from, undef, -ident)
1155 #======================================================================
1157 #======================================================================
1159 sub _expand_maybe_list_expr {
1160 my ($self, $expr, $logic, $default) = @_;
1162 if (ref($expr) eq 'ARRAY') {
1164 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1171 return $self->_expand_expr($e, $logic, $default);
1174 # highly optimized, as it's called way too often
1176 # my ($self, $label) = @_;
1178 return '' unless defined $_[1];
1179 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1180 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1182 unless ($_[0]->{quote_char}) {
1183 if (ref($_[1]) eq 'ARRAY') {
1184 return join($_[0]->{name_sep}||'.', @{$_[1]});
1186 $_[0]->_assert_pass_injection_guard($_[1]);
1191 my $qref = ref $_[0]->{quote_char};
1193 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1194 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1195 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1197 my $esc = $_[0]->{escape_char} || $r;
1199 # parts containing * are naturally unquoted
1201 $_[0]->{name_sep}||'',
1205 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1207 (ref($_[1]) eq 'ARRAY'
1211 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1219 # Conversion, if applicable
1221 #my ($self, $arg) = @_;
1222 if ($_[0]->{convert_where}) {
1223 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1230 #my ($self, $col, @vals) = @_;
1231 # called often - tighten code
1232 return $_[0]->{bindtype} eq 'columns'
1233 ? map {[$_[1], $_]} @_[2 .. $#_]
1238 # Dies if any element of @bind is not in [colname => value] format
1239 # if bindtype is 'columns'.
1240 sub _assert_bindval_matches_bindtype {
1241 # my ($self, @bind) = @_;
1243 if ($self->{bindtype} eq 'columns') {
1245 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1246 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1252 sub _join_sql_clauses {
1253 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1255 if (@$clauses_aref > 1) {
1256 my $join = " " . $self->_sqlcase($logic) . " ";
1257 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1258 return ($sql, @$bind_aref);
1260 elsif (@$clauses_aref) {
1261 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1264 return (); # if no SQL, ignore @$bind_aref
1269 # Fix SQL case, if so requested
1271 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1272 # don't touch the argument ... crooked logic, but let's not change it!
1273 return $_[0]->{case} ? $_[1] : uc($_[1]);
1277 #======================================================================
1278 # DISPATCHING FROM REFKIND
1279 #======================================================================
1282 my ($self, $data) = @_;
1284 return 'UNDEF' unless defined $data;
1286 # blessed objects are treated like scalars
1287 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1289 return 'SCALAR' unless $ref;
1292 while ($ref eq 'REF') {
1294 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1298 return ($ref||'SCALAR') . ('REF' x $n_steps);
1302 my ($self, $data) = @_;
1303 my @try = ($self->_refkind($data));
1304 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1305 push @try, 'FALLBACK';
1309 sub _METHOD_FOR_refkind {
1310 my ($self, $meth_prefix, $data) = @_;
1313 for (@{$self->_try_refkind($data)}) {
1314 $method = $self->can($meth_prefix."_".$_)
1318 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1322 sub _SWITCH_refkind {
1323 my ($self, $data, $dispatch_table) = @_;
1326 for (@{$self->_try_refkind($data)}) {
1327 $coderef = $dispatch_table->{$_}
1331 puke "no dispatch entry for ".$self->_refkind($data)
1340 #======================================================================
1341 # VALUES, GENERATE, AUTOLOAD
1342 #======================================================================
1344 # LDNOTE: original code from nwiger, didn't touch code in that section
1345 # I feel the AUTOLOAD stuff should not be the default, it should
1346 # only be activated on explicit demand by user.
1350 my $data = shift || return;
1351 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1352 unless ref $data eq 'HASH';
1355 foreach my $k (sort keys %$data) {
1356 my $v = $data->{$k};
1357 $self->_SWITCH_refkind($v, {
1359 if ($self->{array_datatypes}) { # array datatype
1360 push @all_bind, $self->_bindtype($k, $v);
1362 else { # literal SQL with bind
1363 my ($sql, @bind) = @$v;
1364 $self->_assert_bindval_matches_bindtype(@bind);
1365 push @all_bind, @bind;
1368 ARRAYREFREF => sub { # literal SQL with bind
1369 my ($sql, @bind) = @${$v};
1370 $self->_assert_bindval_matches_bindtype(@bind);
1371 push @all_bind, @bind;
1373 SCALARREF => sub { # literal SQL without bind
1375 SCALAR_or_UNDEF => sub {
1376 push @all_bind, $self->_bindtype($k, $v);
1387 my(@sql, @sqlq, @sqlv);
1391 if ($ref eq 'HASH') {
1392 for my $k (sort keys %$_) {
1395 my $label = $self->_quote($k);
1396 if ($r eq 'ARRAY') {
1397 # literal SQL with bind
1398 my ($sql, @bind) = @$v;
1399 $self->_assert_bindval_matches_bindtype(@bind);
1400 push @sqlq, "$label = $sql";
1402 } elsif ($r eq 'SCALAR') {
1403 # literal SQL without bind
1404 push @sqlq, "$label = $$v";
1406 push @sqlq, "$label = ?";
1407 push @sqlv, $self->_bindtype($k, $v);
1410 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1411 } elsif ($ref eq 'ARRAY') {
1412 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1415 if ($r eq 'ARRAY') { # literal SQL with bind
1416 my ($sql, @bind) = @$v;
1417 $self->_assert_bindval_matches_bindtype(@bind);
1420 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1421 # embedded literal SQL
1428 push @sql, '(' . join(', ', @sqlq) . ')';
1429 } elsif ($ref eq 'SCALAR') {
1433 # strings get case twiddled
1434 push @sql, $self->_sqlcase($_);
1438 my $sql = join ' ', @sql;
1440 # this is pretty tricky
1441 # if ask for an array, return ($stmt, @bind)
1442 # otherwise, s/?/shift @sqlv/ to put it inline
1444 return ($sql, @sqlv);
1446 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1447 ref $d ? $d->[1] : $d/e;
1456 # This allows us to check for a local, then _form, attr
1458 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1459 return $self->generate($name, @_);
1470 SQL::Abstract - Generate SQL from Perl data structures
1476 my $sql = SQL::Abstract->new;
1478 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1480 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1482 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1484 my($stmt, @bind) = $sql->delete($table, \%where);
1486 # Then, use these in your DBI statements
1487 my $sth = $dbh->prepare($stmt);
1488 $sth->execute(@bind);
1490 # Just generate the WHERE clause
1491 my($stmt, @bind) = $sql->where(\%where, $order);
1493 # Return values in the same order, for hashed queries
1494 # See PERFORMANCE section for more details
1495 my @bind = $sql->values(\%fieldvals);
1499 This module was inspired by the excellent L<DBIx::Abstract>.
1500 However, in using that module I found that what I really wanted
1501 to do was generate SQL, but still retain complete control over my
1502 statement handles and use the DBI interface. So, I set out to
1503 create an abstract SQL generation module.
1505 While based on the concepts used by L<DBIx::Abstract>, there are
1506 several important differences, especially when it comes to WHERE
1507 clauses. I have modified the concepts used to make the SQL easier
1508 to generate from Perl data structures and, IMO, more intuitive.
1509 The underlying idea is for this module to do what you mean, based
1510 on the data structures you provide it. The big advantage is that
1511 you don't have to modify your code every time your data changes,
1512 as this module figures it out.
1514 To begin with, an SQL INSERT is as easy as just specifying a hash
1515 of C<key=value> pairs:
1518 name => 'Jimbo Bobson',
1519 phone => '123-456-7890',
1520 address => '42 Sister Lane',
1521 city => 'St. Louis',
1522 state => 'Louisiana',
1525 The SQL can then be generated with this:
1527 my($stmt, @bind) = $sql->insert('people', \%data);
1529 Which would give you something like this:
1531 $stmt = "INSERT INTO people
1532 (address, city, name, phone, state)
1533 VALUES (?, ?, ?, ?, ?)";
1534 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1535 '123-456-7890', 'Louisiana');
1537 These are then used directly in your DBI code:
1539 my $sth = $dbh->prepare($stmt);
1540 $sth->execute(@bind);
1542 =head2 Inserting and Updating Arrays
1544 If your database has array types (like for example Postgres),
1545 activate the special option C<< array_datatypes => 1 >>
1546 when creating the C<SQL::Abstract> object.
1547 Then you may use an arrayref to insert and update database array types:
1549 my $sql = SQL::Abstract->new(array_datatypes => 1);
1551 planets => [qw/Mercury Venus Earth Mars/]
1554 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1558 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1560 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1563 =head2 Inserting and Updating SQL
1565 In order to apply SQL functions to elements of your C<%data> you may
1566 specify a reference to an arrayref for the given hash value. For example,
1567 if you need to execute the Oracle C<to_date> function on a value, you can
1568 say something like this:
1572 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1575 The first value in the array is the actual SQL. Any other values are
1576 optional and would be included in the bind values array. This gives
1579 my($stmt, @bind) = $sql->insert('people', \%data);
1581 $stmt = "INSERT INTO people (name, date_entered)
1582 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1583 @bind = ('Bill', '03/02/2003');
1585 An UPDATE is just as easy, all you change is the name of the function:
1587 my($stmt, @bind) = $sql->update('people', \%data);
1589 Notice that your C<%data> isn't touched; the module will generate
1590 the appropriately quirky SQL for you automatically. Usually you'll
1591 want to specify a WHERE clause for your UPDATE, though, which is
1592 where handling C<%where> hashes comes in handy...
1594 =head2 Complex where statements
1596 This module can generate pretty complicated WHERE statements
1597 easily. For example, simple C<key=value> pairs are taken to mean
1598 equality, and if you want to see if a field is within a set
1599 of values, you can use an arrayref. Let's say we wanted to
1600 SELECT some data based on this criteria:
1603 requestor => 'inna',
1604 worker => ['nwiger', 'rcwe', 'sfz'],
1605 status => { '!=', 'completed' }
1608 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1610 The above would give you something like this:
1612 $stmt = "SELECT * FROM tickets WHERE
1613 ( requestor = ? ) AND ( status != ? )
1614 AND ( worker = ? OR worker = ? OR worker = ? )";
1615 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1617 Which you could then use in DBI code like so:
1619 my $sth = $dbh->prepare($stmt);
1620 $sth->execute(@bind);
1626 The methods are simple. There's one for every major SQL operation,
1627 and a constructor you use first. The arguments are specified in a
1628 similar order for each method (table, then fields, then a where
1629 clause) to try and simplify things.
1631 =head2 new(option => 'value')
1633 The C<new()> function takes a list of options and values, and returns
1634 a new B<SQL::Abstract> object which can then be used to generate SQL
1635 through the methods below. The options accepted are:
1641 If set to 'lower', then SQL will be generated in all lowercase. By
1642 default SQL is generated in "textbook" case meaning something like:
1644 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1646 Any setting other than 'lower' is ignored.
1650 This determines what the default comparison operator is. By default
1651 it is C<=>, meaning that a hash like this:
1653 %where = (name => 'nwiger', email => 'nate@wiger.org');
1655 Will generate SQL like this:
1657 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1659 However, you may want loose comparisons by default, so if you set
1660 C<cmp> to C<like> you would get SQL such as:
1662 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1664 You can also override the comparison on an individual basis - see
1665 the huge section on L</"WHERE CLAUSES"> at the bottom.
1667 =item sqltrue, sqlfalse
1669 Expressions for inserting boolean values within SQL statements.
1670 By default these are C<1=1> and C<1=0>. They are used
1671 by the special operators C<-in> and C<-not_in> for generating
1672 correct SQL even when the argument is an empty array (see below).
1676 This determines the default logical operator for multiple WHERE
1677 statements in arrays or hashes. If absent, the default logic is "or"
1678 for arrays, and "and" for hashes. This means that a WHERE
1682 event_date => {'>=', '2/13/99'},
1683 event_date => {'<=', '4/24/03'},
1686 will generate SQL like this:
1688 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1690 This is probably not what you want given this query, though (look
1691 at the dates). To change the "OR" to an "AND", simply specify:
1693 my $sql = SQL::Abstract->new(logic => 'and');
1695 Which will change the above C<WHERE> to:
1697 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1699 The logic can also be changed locally by inserting
1700 a modifier in front of an arrayref:
1702 @where = (-and => [event_date => {'>=', '2/13/99'},
1703 event_date => {'<=', '4/24/03'} ]);
1705 See the L</"WHERE CLAUSES"> section for explanations.
1709 This will automatically convert comparisons using the specified SQL
1710 function for both column and value. This is mostly used with an argument
1711 of C<upper> or C<lower>, so that the SQL will have the effect of
1712 case-insensitive "searches". For example, this:
1714 $sql = SQL::Abstract->new(convert => 'upper');
1715 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1717 Will turn out the following SQL:
1719 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1721 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1722 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1723 not validate this option; it will just pass through what you specify verbatim).
1727 This is a kludge because many databases suck. For example, you can't
1728 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1729 Instead, you have to use C<bind_param()>:
1731 $sth->bind_param(1, 'reg data');
1732 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1734 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1735 which loses track of which field each slot refers to. Fear not.
1737 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1738 Currently, you can specify either C<normal> (default) or C<columns>. If you
1739 specify C<columns>, you will get an array that looks like this:
1741 my $sql = SQL::Abstract->new(bindtype => 'columns');
1742 my($stmt, @bind) = $sql->insert(...);
1745 [ 'column1', 'value1' ],
1746 [ 'column2', 'value2' ],
1747 [ 'column3', 'value3' ],
1750 You can then iterate through this manually, using DBI's C<bind_param()>.
1752 $sth->prepare($stmt);
1755 my($col, $data) = @$_;
1756 if ($col eq 'details' || $col eq 'comments') {
1757 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1758 } elsif ($col eq 'image') {
1759 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1761 $sth->bind_param($i, $data);
1765 $sth->execute; # execute without @bind now
1767 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1768 Basically, the advantage is still that you don't have to care which fields
1769 are or are not included. You could wrap that above C<for> loop in a simple
1770 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1771 get a layer of abstraction over manual SQL specification.
1773 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1774 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1775 will expect the bind values in this format.
1779 This is the character that a table or column name will be quoted
1780 with. By default this is an empty string, but you could set it to
1781 the character C<`>, to generate SQL like this:
1783 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1785 Alternatively, you can supply an array ref of two items, the first being the left
1786 hand quote character, and the second the right hand quote character. For
1787 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1788 that generates SQL like this:
1790 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1792 Quoting is useful if you have tables or columns names that are reserved
1793 words in your database's SQL dialect.
1797 This is the character that will be used to escape L</quote_char>s appearing
1798 in an identifier before it has been quoted.
1800 The parameter default in case of a single L</quote_char> character is the quote
1803 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1804 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1805 of the B<opening (left)> L</quote_char> within the identifier are currently left
1806 untouched. The default for opening-closing-style quotes may change in future
1807 versions, thus you are B<strongly encouraged> to specify the escape character
1812 This is the character that separates a table and column name. It is
1813 necessary to specify this when the C<quote_char> option is selected,
1814 so that tables and column names can be individually quoted like this:
1816 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1818 =item injection_guard
1820 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1821 column name specified in a query structure. This is a safety mechanism to avoid
1822 injection attacks when mishandling user input e.g.:
1824 my %condition_as_column_value_pairs = get_values_from_user();
1825 $sqla->select( ... , \%condition_as_column_value_pairs );
1827 If the expression matches an exception is thrown. Note that literal SQL
1828 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1830 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1832 =item array_datatypes
1834 When this option is true, arrayrefs in INSERT or UPDATE are
1835 interpreted as array datatypes and are passed directly
1837 When this option is false, arrayrefs are interpreted
1838 as literal SQL, just like refs to arrayrefs
1839 (but this behavior is for backwards compatibility; when writing
1840 new queries, use the "reference to arrayref" syntax
1846 Takes a reference to a list of "special operators"
1847 to extend the syntax understood by L<SQL::Abstract>.
1848 See section L</"SPECIAL OPERATORS"> for details.
1852 Takes a reference to a list of "unary operators"
1853 to extend the syntax understood by L<SQL::Abstract>.
1854 See section L</"UNARY OPERATORS"> for details.
1860 =head2 insert($table, \@values || \%fieldvals, \%options)
1862 This is the simplest function. You simply give it a table name
1863 and either an arrayref of values or hashref of field/value pairs.
1864 It returns an SQL INSERT statement and a list of bind values.
1865 See the sections on L</"Inserting and Updating Arrays"> and
1866 L</"Inserting and Updating SQL"> for information on how to insert
1867 with those data types.
1869 The optional C<\%options> hash reference may contain additional
1870 options to generate the insert SQL. Currently supported options
1877 Takes either a scalar of raw SQL fields, or an array reference of
1878 field names, and adds on an SQL C<RETURNING> statement at the end.
1879 This allows you to return data generated by the insert statement
1880 (such as row IDs) without performing another C<SELECT> statement.
1881 Note, however, this is not part of the SQL standard and may not
1882 be supported by all database engines.
1886 =head2 update($table, \%fieldvals, \%where, \%options)
1888 This takes a table, hashref of field/value pairs, and an optional
1889 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1891 See the sections on L</"Inserting and Updating Arrays"> and
1892 L</"Inserting and Updating SQL"> for information on how to insert
1893 with those data types.
1895 The optional C<\%options> hash reference may contain additional
1896 options to generate the update SQL. Currently supported options
1903 See the C<returning> option to
1904 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1908 =head2 select($source, $fields, $where, $order)
1910 This returns a SQL SELECT statement and associated list of bind values, as
1911 specified by the arguments:
1917 Specification of the 'FROM' part of the statement.
1918 The argument can be either a plain scalar (interpreted as a table
1919 name, will be quoted), or an arrayref (interpreted as a list
1920 of table names, joined by commas, quoted), or a scalarref
1921 (literal SQL, not quoted).
1925 Specification of the list of fields to retrieve from
1927 The argument can be either an arrayref (interpreted as a list
1928 of field names, will be joined by commas and quoted), or a
1929 plain scalar (literal SQL, not quoted).
1930 Please observe that this API is not as flexible as that of
1931 the first argument C<$source>, for backwards compatibility reasons.
1935 Optional argument to specify the WHERE part of the query.
1936 The argument is most often a hashref, but can also be
1937 an arrayref or plain scalar --
1938 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1942 Optional argument to specify the ORDER BY part of the query.
1943 The argument can be a scalar, a hashref or an arrayref
1944 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1950 =head2 delete($table, \%where, \%options)
1952 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1953 It returns an SQL DELETE statement and list of bind values.
1955 The optional C<\%options> hash reference may contain additional
1956 options to generate the delete SQL. Currently supported options
1963 See the C<returning> option to
1964 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1968 =head2 where(\%where, $order)
1970 This is used to generate just the WHERE clause. For example,
1971 if you have an arbitrary data structure and know what the
1972 rest of your SQL is going to look like, but want an easy way
1973 to produce a WHERE clause, use this. It returns an SQL WHERE
1974 clause and list of bind values.
1977 =head2 values(\%data)
1979 This just returns the values from the hash C<%data>, in the same
1980 order that would be returned from any of the other above queries.
1981 Using this allows you to markedly speed up your queries if you
1982 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1984 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1986 Warning: This is an experimental method and subject to change.
1988 This returns arbitrarily generated SQL. It's a really basic shortcut.
1989 It will return two different things, depending on return context:
1991 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1992 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1994 These would return the following:
1996 # First calling form
1997 $stmt = "CREATE TABLE test (?, ?)";
1998 @bind = (field1, field2);
2000 # Second calling form
2001 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2003 Depending on what you're trying to do, it's up to you to choose the correct
2004 format. In this example, the second form is what you would want.
2008 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2012 ALTER SESSION SET nls_date_format = 'MM/YY'
2014 You get the idea. Strings get their case twiddled, but everything
2015 else remains verbatim.
2017 =head1 EXPORTABLE FUNCTIONS
2019 =head2 is_plain_value
2021 Determines if the supplied argument is a plain value as understood by this
2026 =item * The value is C<undef>
2028 =item * The value is a non-reference
2030 =item * The value is an object with stringification overloading
2032 =item * The value is of the form C<< { -value => $anything } >>
2036 On failure returns C<undef>, on success returns a B<scalar> reference
2037 to the original supplied argument.
2043 The stringification overloading detection is rather advanced: it takes
2044 into consideration not only the presence of a C<""> overload, but if that
2045 fails also checks for enabled
2046 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2047 on either C<0+> or C<bool>.
2049 Unfortunately testing in the field indicates that this
2050 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2051 but only when very large numbers of stringifying objects are involved.
2052 At the time of writing ( Sep 2014 ) there is no clear explanation of
2053 the direct cause, nor is there a manageably small test case that reliably
2054 reproduces the problem.
2056 If you encounter any of the following exceptions in B<random places within
2057 your application stack> - this module may be to blame:
2059 Operation "ne": no method found,
2060 left argument in overloaded package <something>,
2061 right argument in overloaded package <something>
2065 Stub found while resolving method "???" overloading """" in package <something>
2067 If you fall victim to the above - please attempt to reduce the problem
2068 to something that could be sent to the L<SQL::Abstract developers
2069 |DBIx::Class/GETTING HELP/SUPPORT>
2070 (either publicly or privately). As a workaround in the meantime you can
2071 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2072 value, which will most likely eliminate your problem (at the expense of
2073 not being able to properly detect exotic forms of stringification).
2075 This notice and environment variable will be removed in a future version,
2076 as soon as the underlying problem is found and a reliable workaround is
2081 =head2 is_literal_value
2083 Determines if the supplied argument is a literal value as understood by this
2088 =item * C<\$sql_string>
2090 =item * C<\[ $sql_string, @bind_values ]>
2094 On failure returns C<undef>, on success returns an B<array> reference
2095 containing the unpacked version of the supplied literal SQL and bind values.
2097 =head1 WHERE CLAUSES
2101 This module uses a variation on the idea from L<DBIx::Abstract>. It
2102 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2103 module is that things in arrays are OR'ed, and things in hashes
2106 The easiest way to explain is to show lots of examples. After
2107 each C<%where> hash shown, it is assumed you used:
2109 my($stmt, @bind) = $sql->where(\%where);
2111 However, note that the C<%where> hash can be used directly in any
2112 of the other functions as well, as described above.
2114 =head2 Key-value pairs
2116 So, let's get started. To begin, a simple hash:
2120 status => 'completed'
2123 Is converted to SQL C<key = val> statements:
2125 $stmt = "WHERE user = ? AND status = ?";
2126 @bind = ('nwiger', 'completed');
2128 One common thing I end up doing is having a list of values that
2129 a field can be in. To do this, simply specify a list inside of
2134 status => ['assigned', 'in-progress', 'pending'];
2137 This simple code will create the following:
2139 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2140 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2142 A field associated to an empty arrayref will be considered a
2143 logical false and will generate 0=1.
2145 =head2 Tests for NULL values
2147 If the value part is C<undef> then this is converted to SQL <IS NULL>
2156 $stmt = "WHERE user = ? AND status IS NULL";
2159 To test if a column IS NOT NULL:
2163 status => { '!=', undef },
2166 =head2 Specific comparison operators
2168 If you want to specify a different type of operator for your comparison,
2169 you can use a hashref for a given column:
2173 status => { '!=', 'completed' }
2176 Which would generate:
2178 $stmt = "WHERE user = ? AND status != ?";
2179 @bind = ('nwiger', 'completed');
2181 To test against multiple values, just enclose the values in an arrayref:
2183 status => { '=', ['assigned', 'in-progress', 'pending'] };
2185 Which would give you:
2187 "WHERE status = ? OR status = ? OR status = ?"
2190 The hashref can also contain multiple pairs, in which case it is expanded
2191 into an C<AND> of its elements:
2195 status => { '!=', 'completed', -not_like => 'pending%' }
2198 # Or more dynamically, like from a form
2199 $where{user} = 'nwiger';
2200 $where{status}{'!='} = 'completed';
2201 $where{status}{'-not_like'} = 'pending%';
2203 # Both generate this
2204 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2205 @bind = ('nwiger', 'completed', 'pending%');
2208 To get an OR instead, you can combine it with the arrayref idea:
2212 priority => [ { '=', 2 }, { '>', 5 } ]
2215 Which would generate:
2217 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2218 @bind = ('2', '5', 'nwiger');
2220 If you want to include literal SQL (with or without bind values), just use a
2221 scalar reference or reference to an arrayref as the value:
2224 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2225 date_expires => { '<' => \"now()" }
2228 Which would generate:
2230 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2231 @bind = ('11/26/2008');
2234 =head2 Logic and nesting operators
2236 In the example above,
2237 there is a subtle trap if you want to say something like
2238 this (notice the C<AND>):
2240 WHERE priority != ? AND priority != ?
2242 Because, in Perl you I<can't> do this:
2244 priority => { '!=' => 2, '!=' => 1 }
2246 As the second C<!=> key will obliterate the first. The solution
2247 is to use the special C<-modifier> form inside an arrayref:
2249 priority => [ -and => {'!=', 2},
2253 Normally, these would be joined by C<OR>, but the modifier tells it
2254 to use C<AND> instead. (Hint: You can use this in conjunction with the
2255 C<logic> option to C<new()> in order to change the way your queries
2256 work by default.) B<Important:> Note that the C<-modifier> goes
2257 B<INSIDE> the arrayref, as an extra first element. This will
2258 B<NOT> do what you think it might:
2260 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2262 Here is a quick list of equivalencies, since there is some overlap:
2265 status => {'!=', 'completed', 'not like', 'pending%' }
2266 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2269 status => {'=', ['assigned', 'in-progress']}
2270 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2271 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2275 =head2 Special operators: IN, BETWEEN, etc.
2277 You can also use the hashref format to compare a list of fields using the
2278 C<IN> comparison operator, by specifying the list as an arrayref:
2281 status => 'completed',
2282 reportid => { -in => [567, 2335, 2] }
2285 Which would generate:
2287 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2288 @bind = ('completed', '567', '2335', '2');
2290 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2293 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2294 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2295 'sqltrue' (by default: C<1=1>).
2297 In addition to the array you can supply a chunk of literal sql or
2298 literal sql with bind:
2301 customer => { -in => \[
2302 'SELECT cust_id FROM cust WHERE balance > ?',
2305 status => { -in => \'SELECT status_codes FROM states' },
2311 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2312 AND status IN ( SELECT status_codes FROM states )
2316 Finally, if the argument to C<-in> is not a reference, it will be
2317 treated as a single-element array.
2319 Another pair of operators is C<-between> and C<-not_between>,
2320 used with an arrayref of two values:
2324 completion_date => {
2325 -not_between => ['2002-10-01', '2003-02-06']
2331 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2333 Just like with C<-in> all plausible combinations of literal SQL
2337 start0 => { -between => [ 1, 2 ] },
2338 start1 => { -between => \["? AND ?", 1, 2] },
2339 start2 => { -between => \"lower(x) AND upper(y)" },
2340 start3 => { -between => [
2342 \["upper(?)", 'stuff' ],
2349 ( start0 BETWEEN ? AND ? )
2350 AND ( start1 BETWEEN ? AND ? )
2351 AND ( start2 BETWEEN lower(x) AND upper(y) )
2352 AND ( start3 BETWEEN lower(x) AND upper(?) )
2354 @bind = (1, 2, 1, 2, 'stuff');
2357 These are the two builtin "special operators"; but the
2358 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2360 =head2 Unary operators: bool
2362 If you wish to test against boolean columns or functions within your
2363 database you can use the C<-bool> and C<-not_bool> operators. For
2364 example to test the column C<is_user> being true and the column
2365 C<is_enabled> being false you would use:-
2369 -not_bool => 'is_enabled',
2374 WHERE is_user AND NOT is_enabled
2376 If a more complex combination is required, testing more conditions,
2377 then you should use the and/or operators:-
2382 -not_bool => { two=> { -rlike => 'bar' } },
2383 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2394 (NOT ( three = ? OR three > ? ))
2397 =head2 Nested conditions, -and/-or prefixes
2399 So far, we've seen how multiple conditions are joined with a top-level
2400 C<AND>. We can change this by putting the different conditions we want in
2401 hashes and then putting those hashes in an array. For example:
2406 status => { -like => ['pending%', 'dispatched'] },
2410 status => 'unassigned',
2414 This data structure would create the following:
2416 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2417 OR ( user = ? AND status = ? ) )";
2418 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2421 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2422 to change the logic inside:
2428 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2429 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2436 $stmt = "WHERE ( user = ?
2437 AND ( ( workhrs > ? AND geo = ? )
2438 OR ( workhrs < ? OR geo = ? ) ) )";
2439 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2441 =head3 Algebraic inconsistency, for historical reasons
2443 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2444 operator goes C<outside> of the nested structure; whereas when connecting
2445 several constraints on one column, the C<-and> operator goes
2446 C<inside> the arrayref. Here is an example combining both features:
2449 -and => [a => 1, b => 2],
2450 -or => [c => 3, d => 4],
2451 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2456 WHERE ( ( ( a = ? AND b = ? )
2457 OR ( c = ? OR d = ? )
2458 OR ( e LIKE ? AND e LIKE ? ) ) )
2460 This difference in syntax is unfortunate but must be preserved for
2461 historical reasons. So be careful: the two examples below would
2462 seem algebraically equivalent, but they are not
2465 { -like => 'foo%' },
2466 { -like => '%bar' },
2468 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2471 { col => { -like => 'foo%' } },
2472 { col => { -like => '%bar' } },
2474 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2477 =head2 Literal SQL and value type operators
2479 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2480 side" is a column name and the "right side" is a value (normally rendered as
2481 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2482 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2483 alter this behavior. There are several ways of doing so.
2487 This is a virtual operator that signals the string to its right side is an
2488 identifier (a column name) and not a value. For example to compare two
2489 columns you would write:
2492 priority => { '<', 2 },
2493 requestor => { -ident => 'submitter' },
2498 $stmt = "WHERE priority < ? AND requestor = submitter";
2501 If you are maintaining legacy code you may see a different construct as
2502 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2507 This is a virtual operator that signals that the construct to its right side
2508 is a value to be passed to DBI. This is for example necessary when you want
2509 to write a where clause against an array (for RDBMS that support such
2510 datatypes). For example:
2513 array => { -value => [1, 2, 3] }
2518 $stmt = 'WHERE array = ?';
2519 @bind = ([1, 2, 3]);
2521 Note that if you were to simply say:
2527 the result would probably not be what you wanted:
2529 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2534 Finally, sometimes only literal SQL will do. To include a random snippet
2535 of SQL verbatim, you specify it as a scalar reference. Consider this only
2536 as a last resort. Usually there is a better way. For example:
2539 priority => { '<', 2 },
2540 requestor => { -in => \'(SELECT name FROM hitmen)' },
2545 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2548 Note that in this example, you only get one bind parameter back, since
2549 the verbatim SQL is passed as part of the statement.
2553 Never use untrusted input as a literal SQL argument - this is a massive
2554 security risk (there is no way to check literal snippets for SQL
2555 injections and other nastyness). If you need to deal with untrusted input
2556 use literal SQL with placeholders as described next.
2558 =head3 Literal SQL with placeholders and bind values (subqueries)
2560 If the literal SQL to be inserted has placeholders and bind values,
2561 use a reference to an arrayref (yes this is a double reference --
2562 not so common, but perfectly legal Perl). For example, to find a date
2563 in Postgres you can use something like this:
2566 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2571 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2574 Note that you must pass the bind values in the same format as they are returned
2575 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2576 to C<columns>, you must provide the bind values in the
2577 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2578 scalar value; most commonly the column name, but you can use any scalar value
2579 (including references and blessed references), L<SQL::Abstract> will simply
2580 pass it through intact. So if C<bindtype> is set to C<columns> the above
2581 example will look like:
2584 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2587 Literal SQL is especially useful for nesting parenthesized clauses in the
2588 main SQL query. Here is a first example:
2590 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2594 bar => \["IN ($sub_stmt)" => @sub_bind],
2599 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2600 WHERE c2 < ? AND c3 LIKE ?))";
2601 @bind = (1234, 100, "foo%");
2603 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2604 are expressed in the same way. Of course the C<$sub_stmt> and
2605 its associated bind values can be generated through a former call
2608 my ($sub_stmt, @sub_bind)
2609 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2610 c3 => {-like => "foo%"}});
2613 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2616 In the examples above, the subquery was used as an operator on a column;
2617 but the same principle also applies for a clause within the main C<%where>
2618 hash, like an EXISTS subquery:
2620 my ($sub_stmt, @sub_bind)
2621 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2622 my %where = ( -and => [
2624 \["EXISTS ($sub_stmt)" => @sub_bind],
2629 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2630 WHERE c1 = ? AND c2 > t0.c0))";
2634 Observe that the condition on C<c2> in the subquery refers to
2635 column C<t0.c0> of the main query: this is I<not> a bind
2636 value, so we have to express it through a scalar ref.
2637 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2638 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2639 what we wanted here.
2641 Finally, here is an example where a subquery is used
2642 for expressing unary negation:
2644 my ($sub_stmt, @sub_bind)
2645 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2646 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2648 lname => {like => '%son%'},
2649 \["NOT ($sub_stmt)" => @sub_bind],
2654 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2655 @bind = ('%son%', 10, 20)
2657 =head3 Deprecated usage of Literal SQL
2659 Below are some examples of archaic use of literal SQL. It is shown only as
2660 reference for those who deal with legacy code. Each example has a much
2661 better, cleaner and safer alternative that users should opt for in new code.
2667 my %where = ( requestor => \'IS NOT NULL' )
2669 $stmt = "WHERE requestor IS NOT NULL"
2671 This used to be the way of generating NULL comparisons, before the handling
2672 of C<undef> got formalized. For new code please use the superior syntax as
2673 described in L</Tests for NULL values>.
2677 my %where = ( requestor => \'= submitter' )
2679 $stmt = "WHERE requestor = submitter"
2681 This used to be the only way to compare columns. Use the superior L</-ident>
2682 method for all new code. For example an identifier declared in such a way
2683 will be properly quoted if L</quote_char> is properly set, while the legacy
2684 form will remain as supplied.
2688 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2690 $stmt = "WHERE completed > ? AND is_ready"
2691 @bind = ('2012-12-21')
2693 Using an empty string literal used to be the only way to express a boolean.
2694 For all new code please use the much more readable
2695 L<-bool|/Unary operators: bool> operator.
2701 These pages could go on for a while, since the nesting of the data
2702 structures this module can handle are pretty much unlimited (the
2703 module implements the C<WHERE> expansion as a recursive function
2704 internally). Your best bet is to "play around" with the module a
2705 little to see how the data structures behave, and choose the best
2706 format for your data based on that.
2708 And of course, all the values above will probably be replaced with
2709 variables gotten from forms or the command line. After all, if you
2710 knew everything ahead of time, you wouldn't have to worry about
2711 dynamically-generating SQL and could just hardwire it into your
2714 =head1 ORDER BY CLAUSES
2716 Some functions take an order by clause. This can either be a scalar (just a
2717 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2718 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2721 Given | Will Generate
2722 ---------------------------------------------------------------
2724 'colA' | ORDER BY colA
2726 [qw/colA colB/] | ORDER BY colA, colB
2728 {-asc => 'colA'} | ORDER BY colA ASC
2730 {-desc => 'colB'} | ORDER BY colB DESC
2732 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2734 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2736 \'colA DESC' | ORDER BY colA DESC
2738 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2739 | /* ...with $x bound to ? */
2742 { -asc => 'colA' }, | colA ASC,
2743 { -desc => [qw/colB/] }, | colB DESC,
2744 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2745 \'colE DESC', | colE DESC,
2746 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2747 ] | /* ...with $x bound to ? */
2748 ===============================================================
2752 =head1 SPECIAL OPERATORS
2754 my $sqlmaker = SQL::Abstract->new(special_ops => [
2758 my ($self, $field, $op, $arg) = @_;
2764 handler => 'method_name',
2768 A "special operator" is a SQL syntactic clause that can be
2769 applied to a field, instead of a usual binary operator.
2772 WHERE field IN (?, ?, ?)
2773 WHERE field BETWEEN ? AND ?
2774 WHERE MATCH(field) AGAINST (?, ?)
2776 Special operators IN and BETWEEN are fairly standard and therefore
2777 are builtin within C<SQL::Abstract> (as the overridable methods
2778 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2779 like the MATCH .. AGAINST example above which is specific to MySQL,
2780 you can write your own operator handlers - supply a C<special_ops>
2781 argument to the C<new> method. That argument takes an arrayref of
2782 operator definitions; each operator definition is a hashref with two
2789 the regular expression to match the operator
2793 Either a coderef or a plain scalar method name. In both cases
2794 the expected return is C<< ($sql, @bind) >>.
2796 When supplied with a method name, it is simply called on the
2797 L<SQL::Abstract> object as:
2799 $self->$method_name($field, $op, $arg)
2803 $field is the LHS of the operator
2804 $op is the part that matched the handler regex
2807 When supplied with a coderef, it is called as:
2809 $coderef->($self, $field, $op, $arg)
2814 For example, here is an implementation
2815 of the MATCH .. AGAINST syntax for MySQL
2817 my $sqlmaker = SQL::Abstract->new(special_ops => [
2819 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2820 {regex => qr/^match$/i,
2822 my ($self, $field, $op, $arg) = @_;
2823 $arg = [$arg] if not ref $arg;
2824 my $label = $self->_quote($field);
2825 my ($placeholder) = $self->_convert('?');
2826 my $placeholders = join ", ", (($placeholder) x @$arg);
2827 my $sql = $self->_sqlcase('match') . " ($label) "
2828 . $self->_sqlcase('against') . " ($placeholders) ";
2829 my @bind = $self->_bindtype($field, @$arg);
2830 return ($sql, @bind);
2837 =head1 UNARY OPERATORS
2839 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2843 my ($self, $op, $arg) = @_;
2849 handler => 'method_name',
2853 A "unary operator" is a SQL syntactic clause that can be
2854 applied to a field - the operator goes before the field
2856 You can write your own operator handlers - supply a C<unary_ops>
2857 argument to the C<new> method. That argument takes an arrayref of
2858 operator definitions; each operator definition is a hashref with two
2865 the regular expression to match the operator
2869 Either a coderef or a plain scalar method name. In both cases
2870 the expected return is C<< $sql >>.
2872 When supplied with a method name, it is simply called on the
2873 L<SQL::Abstract> object as:
2875 $self->$method_name($op, $arg)
2879 $op is the part that matched the handler regex
2880 $arg is the RHS or argument of the operator
2882 When supplied with a coderef, it is called as:
2884 $coderef->($self, $op, $arg)
2892 Thanks to some benchmarking by Mark Stosberg, it turns out that
2893 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2894 I must admit this wasn't an intentional design issue, but it's a
2895 byproduct of the fact that you get to control your C<DBI> handles
2898 To maximize performance, use a code snippet like the following:
2900 # prepare a statement handle using the first row
2901 # and then reuse it for the rest of the rows
2903 for my $href (@array_of_hashrefs) {
2904 $stmt ||= $sql->insert('table', $href);
2905 $sth ||= $dbh->prepare($stmt);
2906 $sth->execute($sql->values($href));
2909 The reason this works is because the keys in your C<$href> are sorted
2910 internally by B<SQL::Abstract>. Thus, as long as your data retains
2911 the same structure, you only have to generate the SQL the first time
2912 around. On subsequent queries, simply use the C<values> function provided
2913 by this module to return your values in the correct order.
2915 However this depends on the values having the same type - if, for
2916 example, the values of a where clause may either have values
2917 (resulting in sql of the form C<column = ?> with a single bind
2918 value), or alternatively the values might be C<undef> (resulting in
2919 sql of the form C<column IS NULL> with no bind value) then the
2920 caching technique suggested will not work.
2924 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2925 really like this part (I do, at least). Building up a complex query
2926 can be as simple as the following:
2933 use CGI::FormBuilder;
2936 my $form = CGI::FormBuilder->new(...);
2937 my $sql = SQL::Abstract->new;
2939 if ($form->submitted) {
2940 my $field = $form->field;
2941 my $id = delete $field->{id};
2942 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2945 Of course, you would still have to connect using C<DBI> to run the
2946 query, but the point is that if you make your form look like your
2947 table, the actual query script can be extremely simplistic.
2949 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2950 a fast interface to returning and formatting data. I frequently
2951 use these three modules together to write complex database query
2952 apps in under 50 lines.
2954 =head1 HOW TO CONTRIBUTE
2956 Contributions are always welcome, in all usable forms (we especially
2957 welcome documentation improvements). The delivery methods include git-
2958 or unified-diff formatted patches, GitHub pull requests, or plain bug
2959 reports either via RT or the Mailing list. Contributors are generally
2960 granted full access to the official repository after their first several
2961 patches pass successful review.
2963 This project is maintained in a git repository. The code and related tools are
2964 accessible at the following locations:
2968 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2970 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2972 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2974 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2980 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2981 Great care has been taken to preserve the I<published> behavior
2982 documented in previous versions in the 1.* family; however,
2983 some features that were previously undocumented, or behaved
2984 differently from the documentation, had to be changed in order
2985 to clarify the semantics. Hence, client code that was relying
2986 on some dark areas of C<SQL::Abstract> v1.*
2987 B<might behave differently> in v1.50.
2989 The main changes are:
2995 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2999 support for the { operator => \"..." } construct (to embed literal SQL)
3003 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3007 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3011 defensive programming: check arguments
3015 fixed bug with global logic, which was previously implemented
3016 through global variables yielding side-effects. Prior versions would
3017 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3018 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3019 Now this is interpreted
3020 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3025 fixed semantics of _bindtype on array args
3029 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3030 we just avoid shifting arrays within that tree.
3034 dropped the C<_modlogic> function
3038 =head1 ACKNOWLEDGEMENTS
3040 There are a number of individuals that have really helped out with
3041 this module. Unfortunately, most of them submitted bugs via CPAN
3042 so I have no idea who they are! But the people I do know are:
3044 Ash Berlin (order_by hash term support)
3045 Matt Trout (DBIx::Class support)
3046 Mark Stosberg (benchmarking)
3047 Chas Owens (initial "IN" operator support)
3048 Philip Collins (per-field SQL functions)
3049 Eric Kolve (hashref "AND" support)
3050 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3051 Dan Kubb (support for "quote_char" and "name_sep")
3052 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3053 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3054 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3055 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3056 Oliver Charles (support for "RETURNING" after "INSERT")
3062 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3066 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3068 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3070 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3071 While not an official support venue, C<DBIx::Class> makes heavy use of
3072 C<SQL::Abstract>, and as such list members there are very familiar with
3073 how to create queries.
3077 This module is free software; you may copy this under the same
3078 terms as perl itself (either the GNU General Public License or
3079 the Artistic License)