1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$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/
187 $opt{node_types} = +{
188 map +("-$_" => '_render_'.$_),
189 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_expr(
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_expr(
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_expr(
383 $self->_expand_update_set_values($data),
387 sub _expand_update_set_values {
388 my ($self, $data) = @_;
389 $self->_expand_maybe_list_expr( [
392 $set = { -bind => $_ } unless defined $set;
393 +{ -op => [ '=', { -ident => $k }, $set ] };
399 ? ($self->{array_datatypes}
400 ? [ $k, +{ -bind => [ $k, $v ] } ]
401 : [ $k, +{ -literal => $v } ])
403 local our $Cur_Col_Meta = $k;
404 [ $k, $self->_expand_expr($v) ]
411 # So that subclasses can override UPDATE ... RETURNING separately from
413 sub _update_returning { shift->_returning(@_) }
417 #======================================================================
419 #======================================================================
424 my $table = $self->_table(shift);
425 my $fields = shift || '*';
429 my ($fields_sql, @bind) = $self->_select_fields($fields);
431 my ($where_sql, @where_bind) = $self->where($where, $order);
432 push @bind, @where_bind;
434 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
435 $self->_sqlcase('from'), $table)
438 return wantarray ? ($sql, @bind) : $sql;
442 my ($self, $fields) = @_;
443 return $fields unless ref($fields);
444 return $self->_render_expr(
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, $logic, $default_scalar_to) = @_;
508 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
509 our $Expand_Depth ||= 0; local $Expand_Depth = $Expand_Depth + 1;
510 return undef unless defined($expr);
511 if (ref($expr) eq 'HASH') {
512 if (keys %$expr > 1) {
516 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
520 return { -literal => [ '' ] } unless keys %$expr;
521 return $self->_expand_expr_hashpair(%$expr, $logic);
523 if (ref($expr) eq 'ARRAY') {
524 my $logic = lc($logic || $self->{logic});
525 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
529 (ref($_) eq 'ARRAY' and @$_)
530 or (ref($_) eq 'HASH' and %$_)
536 while (my ($el) = splice @expr, 0, 1) {
537 puke "Supplying an empty left hand side argument is not supported in array-pairs"
538 unless defined($el) and length($el);
539 my $elref = ref($el);
541 local $Expand_Depth = 0;
542 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
543 } elsif ($elref eq 'ARRAY') {
544 push(@res, $self->_expand_expr($el)) if @$el;
545 } elsif (my $l = is_literal_value($el)) {
546 push @res, { -literal => $l };
547 } elsif ($elref eq 'HASH') {
548 local $Expand_Depth = 0;
549 push @res, $self->_expand_expr($el) if %$el;
554 return { -op => [ $logic, @res ] };
556 if (my $literal = is_literal_value($expr)) {
557 return +{ -literal => $literal };
559 if (!ref($expr) or Scalar::Util::blessed($expr)) {
560 if (my $d = $Default_Scalar_To) {
561 return $self->_expand_expr({ $d => $expr });
563 if (my $m = our $Cur_Col_Meta) {
564 return +{ -bind => [ $m, $expr ] };
566 return +{ -bind => [ undef, $expr ] };
571 sub _expand_expr_hashpair {
572 my ($self, $k, $v, $logic) = @_;
573 unless (defined($k) and length($k)) {
574 if (defined($k) and my $literal = is_literal_value($v)) {
575 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
576 return { -literal => $literal };
578 puke "Supplying an empty left hand side argument is not supported";
581 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
582 if ($k =~ s/ [_\s]? \d+ $//x ) {
583 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
584 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
587 # DBIx::Class requires a nest warning to be emitted once but the private
588 # method it overrode to do so no longer exists
589 if ($self->{is_dbic_sqlmaker}) {
590 unless (our $Nest_Warned) {
592 "-nest in search conditions is deprecated, you most probably wanted:\n"
593 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
598 return $self->_expand_expr($v);
602 return $self->_expand_expr($v);
604 puke "-bool => undef not supported" unless defined($v);
605 return { -ident => $v };
608 return { -op => [ 'not', $self->_expand_expr($v) ] };
610 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
613 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
616 if (my ($logic) = $k =~ /^-(and|or)$/i) {
617 if (ref($v) eq 'HASH') {
618 return $self->_expand_expr($v, $logic);
620 if (ref($v) eq 'ARRAY') {
621 return $self->_expand_expr($v, $logic);
626 $op =~ s/^-// if length($op) > 1;
628 # top level special ops are illegal in general
629 # note that, arguably, if it makes no sense at top level, it also
630 # makes no sense on the other side of an = sign or similar but DBIC
631 # gets disappointingly upset if I disallow it
633 (our $Expand_Depth) == 1
634 and List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}
636 puke "Illegal use of top-level '-$op'"
638 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
639 return { -op => [ $op, $v ] };
642 if ($k eq '-value') {
643 return +{ -bind => [ our $Cur_Col_Meta, $v ] };
645 if (my $custom = $self->{expand_unary}{$k}) {
646 return $self->$custom($v);
648 if ($self->{node_types}{$k}) {
654 and (keys %$v)[0] =~ /^-/
656 my ($func) = $k =~ /^-(.*)$/;
657 if (List::Util::first { $func =~ $_->{regex} } @{$self->{special_ops}}) {
658 return +{ -op => [ $func, $self->_expand_expr($v) ] };
660 return +{ -func => [ $func, $self->_expand_expr($v) ] };
662 if (!ref($v) or is_literal_value($v)) {
663 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
670 and exists $v->{-value}
671 and not defined $v->{-value}
674 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
676 if (!ref($v) or Scalar::Util::blessed($v)) {
677 my $d = our $Default_Scalar_To;
682 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
686 if (ref($v) eq 'HASH') {
690 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
694 return undef unless keys %$v;
698 $self->_assert_pass_injection_guard($vk);
699 if ($vk =~ s/ [_\s]? \d+ $//x ) {
700 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
701 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
703 if ($vk =~ /^(?:not[ _])?between$/) {
704 local our $Cur_Col_Meta = $k;
705 my @rhs = map $self->_expand_expr($_),
706 ref($vv) eq 'ARRAY' ? @$vv : $vv;
708 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
710 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
712 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
715 join(' ', split '_', $vk),
720 if ($vk =~ /^(?:not[ _])?in$/) {
721 if (my $literal = is_literal_value($vv)) {
722 my ($sql, @bind) = @$literal;
723 my $opened_sql = $self->_open_outer_paren($sql);
725 $vk, { -ident => $k },
726 [ { -literal => [ $opened_sql, @bind ] } ]
730 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
731 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
732 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
733 . 'will emit the logically correct SQL instead of raising this exception)'
735 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
737 my @rhs = map $self->_expand_expr($_),
738 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
739 map { defined($_) ? $_: puke($undef_err) }
740 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
741 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
744 join(' ', split '_', $vk),
749 if ($vk eq 'ident') {
750 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
751 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
759 if ($vk eq 'value') {
760 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
764 { -bind => [ $k, $vv ] }
767 if ($vk =~ /^is(?:[ _]not)?$/) {
768 puke "$vk can only take undef as argument"
772 and exists($vv->{-value})
773 and !defined($vv->{-value})
776 return +{ -op => [ $vk.' null', { -ident => $k } ] };
778 if ($vk =~ /^(and|or)$/) {
779 if (ref($vv) eq 'HASH') {
782 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
787 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
788 return { -op => [ $vk, { -ident => $k }, $vv ] };
790 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
794 { -op => [ $vk, $vv ] }
797 if (ref($vv) eq 'ARRAY') {
798 my ($logic, @values) = (
799 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
804 $vk =~ $self->{inequality_op}
805 or join(' ', split '_', $vk) =~ $self->{not_like_op}
807 if (lc($logic) eq '-or' and @values > 1) {
808 my $op = uc join ' ', split '_', $vk;
809 belch "A multi-element arrayref as an argument to the inequality op '$op' "
810 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
811 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
816 # try to DWIM on equality operators
817 my $op = join ' ', split '_', $vk;
819 $op =~ $self->{equality_op} ? $self->sqlfalse
820 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
821 : $op =~ $self->{inequality_op} ? $self->sqltrue
822 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
823 : puke "operator '$op' applied on an empty array (field '$k')";
827 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
835 and exists $vv->{-value}
836 and not defined $vv->{-value}
839 my $op = join ' ', split '_', $vk;
841 $op =~ /^not$/i ? 'is not' # legacy
842 : $op =~ $self->{equality_op} ? 'is'
843 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
844 : $op =~ $self->{inequality_op} ? 'is not'
845 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
846 : puke "unexpected operator '$op' with undef operand";
847 return +{ -op => [ $is.' null', { -ident => $k } ] };
849 local our $Cur_Col_Meta = $k;
853 $self->_expand_expr($vv)
856 if (ref($v) eq 'ARRAY') {
857 return $self->sqlfalse unless @$v;
858 $self->_debug("ARRAY($k) means distribute over elements");
860 $v->[0] =~ /^-((?:and|or))$/i
861 ? ($v = [ @{$v}[1..$#$v] ], $1)
862 : ($self->{logic} || 'or')
866 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
869 if (my $literal = is_literal_value($v)) {
871 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
874 my ($sql, @bind) = @$literal;
875 if ($self->{bindtype} eq 'columns') {
877 $self->_assert_bindval_matches_bindtype($_);
880 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
886 my ($self, $expr) = @_;
887 my ($k, $v, @rest) = %$expr;
889 if (my $meth = $self->{node_types}{$k}) {
890 return $self->$meth($v);
892 die "notreached: $k";
896 my ($self, $where, $logic) = @_;
898 # Special case: top level simple string treated as literal
900 my $where_exp = (ref($where)
901 ? $self->_expand_expr($where, $logic)
902 : { -literal => [ $where ] });
904 # dispatch expanded expression
906 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
907 # DBIx::Class used to call _recurse_where in scalar context
908 # something else might too...
910 return ($sql, @bind);
913 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
919 my ($self, $ident) = @_;
921 return $self->_convert($self->_quote($ident));
924 my %unop_postfix = map +($_ => 1),
925 'is null', 'is not null',
933 my ($self, $args) = @_;
934 my ($left, $low, $high) = @$args;
935 my ($rhsql, @rhbind) = do {
937 puke "Single arg to between must be a literal"
938 unless $low->{-literal};
941 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
942 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
943 @{$l}[1..$#$l], @{$h}[1..$#$h])
946 my ($lhsql, @lhbind) = $self->_render_expr($left);
948 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
952 }), 'between', 'not between'),
956 my ($self, $args) = @_;
957 my ($lhs, $rhs) = @$args;
960 my ($sql, @bind) = $self->_render_expr($_);
961 push @in_bind, @bind;
964 my ($lhsql, @lbind) = $self->_render_expr($lhs);
966 $lhsql.' '.$self->_sqlcase($op).' ( '
977 my ($op, @args) = @$v;
978 $op =~ s/^-// if length($op) > 1;
980 if (my $h = $special{$op}) {
981 return $self->$h(\@args);
983 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
984 if ($us and @args > 1) {
985 puke "Special op '${op}' requires first value to be identifier"
986 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
987 local our $Expand_Depth = 1;
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.')' : $final_sql), @bind);
1003 #} elsif (@args == 0) {
1006 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @args;
1007 return '' unless @parts;
1008 my $is_andor = !!($op =~ /^(and|or)$/);
1009 return @{$parts[0]} if $is_andor and @parts == 1;
1010 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1011 ' '.$self->_sqlcase($final_op).' ',
1016 map @{$_}[1..$#$_], @parts
1023 my ($self, $list) = @_;
1024 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @$list;
1025 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1029 my ($self, $rest) = @_;
1030 my ($func, @args) = @$rest;
1034 push @arg_sql, shift @x;
1036 } map [ $self->_render_expr($_) ], @args;
1037 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1041 my ($self, $bind) = @_;
1042 return ($self->_convert('?'), $self->_bindtype(@$bind));
1045 sub _render_literal {
1046 my ($self, $literal) = @_;
1047 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1051 # Some databases (SQLite) treat col IN (1, 2) different from
1052 # col IN ( (1, 2) ). Use this to strip all outer parens while
1053 # adding them back in the corresponding method
1054 sub _open_outer_paren {
1055 my ($self, $sql) = @_;
1057 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1059 # there are closing parens inside, need the heavy duty machinery
1060 # to reevaluate the extraction starting from $sql (full reevaluation)
1061 if ($inner =~ /\)/) {
1062 require Text::Balanced;
1064 my (undef, $remainder) = do {
1065 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1067 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1070 # the entire expression needs to be a balanced bracketed thing
1071 # (after an extract no remainder sans trailing space)
1072 last if defined $remainder and $remainder =~ /\S/;
1082 #======================================================================
1084 #======================================================================
1086 sub _expand_order_by {
1087 my ($self, $arg) = @_;
1089 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1091 my $expander = sub {
1092 my ($self, $dir, $expr) = @_;
1093 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1094 foreach my $arg (@to_expand) {
1098 and grep /^-(asc|desc)$/, keys %$arg
1100 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1103 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1104 map $self->_expand_expr($_, undef, -ident),
1105 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1106 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1109 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1110 sub { shift->$expander(asc => @_) },
1111 sub { shift->$expander(desc => @_) },
1114 return $self->$expander(undef, $arg);
1118 my ($self, $arg) = @_;
1120 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1122 my ($sql, @bind) = $self->_render_expr($expanded);
1124 return '' unless length($sql);
1126 my $final_sql = $self->_sqlcase(' order by ').$sql;
1128 return wantarray ? ($final_sql, @bind) : $final_sql;
1131 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1133 sub _order_by_chunks {
1134 my ($self, $arg) = @_;
1136 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1138 return $self->_chunkify_order_by($expanded);
1141 sub _chunkify_order_by {
1142 my ($self, $expanded) = @_;
1144 return grep length, $self->_render_expr($expanded)
1145 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1148 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1149 return map $self->_chunkify_order_by($_), @$l;
1151 return [ $self->_render_expr($_) ];
1155 #======================================================================
1156 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1157 #======================================================================
1162 ($self->_render_expr(
1163 $self->_expand_maybe_list_expr($from, undef, -ident)
1168 #======================================================================
1170 #======================================================================
1172 sub _expand_maybe_list_expr {
1173 my ($self, $expr, $logic, $default) = @_;
1175 if (ref($expr) eq 'ARRAY') {
1177 map $self->_expand_expr($_, $logic, $default), @$expr
1184 return $self->_expand_expr($e, $logic, $default);
1187 # highly optimized, as it's called way too often
1189 # my ($self, $label) = @_;
1191 return '' unless defined $_[1];
1192 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1193 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1195 unless ($_[0]->{quote_char}) {
1196 if (ref($_[1]) eq 'ARRAY') {
1197 return join($_[0]->{name_sep}||'.', @{$_[1]});
1199 $_[0]->_assert_pass_injection_guard($_[1]);
1204 my $qref = ref $_[0]->{quote_char};
1206 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1207 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1208 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1210 my $esc = $_[0]->{escape_char} || $r;
1212 # parts containing * are naturally unquoted
1214 $_[0]->{name_sep}||'',
1218 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1220 (ref($_[1]) eq 'ARRAY'
1224 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1232 # Conversion, if applicable
1234 #my ($self, $arg) = @_;
1235 if ($_[0]->{convert_where}) {
1236 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1243 #my ($self, $col, @vals) = @_;
1244 # called often - tighten code
1245 return $_[0]->{bindtype} eq 'columns'
1246 ? map {[$_[1], $_]} @_[2 .. $#_]
1251 # Dies if any element of @bind is not in [colname => value] format
1252 # if bindtype is 'columns'.
1253 sub _assert_bindval_matches_bindtype {
1254 # my ($self, @bind) = @_;
1256 if ($self->{bindtype} eq 'columns') {
1258 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1259 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1265 sub _join_sql_clauses {
1266 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1268 if (@$clauses_aref > 1) {
1269 my $join = " " . $self->_sqlcase($logic) . " ";
1270 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1271 return ($sql, @$bind_aref);
1273 elsif (@$clauses_aref) {
1274 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1277 return (); # if no SQL, ignore @$bind_aref
1282 # Fix SQL case, if so requested
1284 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1285 # don't touch the argument ... crooked logic, but let's not change it!
1286 return $_[0]->{case} ? $_[1] : uc($_[1]);
1290 #======================================================================
1291 # DISPATCHING FROM REFKIND
1292 #======================================================================
1295 my ($self, $data) = @_;
1297 return 'UNDEF' unless defined $data;
1299 # blessed objects are treated like scalars
1300 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1302 return 'SCALAR' unless $ref;
1305 while ($ref eq 'REF') {
1307 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1311 return ($ref||'SCALAR') . ('REF' x $n_steps);
1315 my ($self, $data) = @_;
1316 my @try = ($self->_refkind($data));
1317 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1318 push @try, 'FALLBACK';
1322 sub _METHOD_FOR_refkind {
1323 my ($self, $meth_prefix, $data) = @_;
1326 for (@{$self->_try_refkind($data)}) {
1327 $method = $self->can($meth_prefix."_".$_)
1331 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1335 sub _SWITCH_refkind {
1336 my ($self, $data, $dispatch_table) = @_;
1339 for (@{$self->_try_refkind($data)}) {
1340 $coderef = $dispatch_table->{$_}
1344 puke "no dispatch entry for ".$self->_refkind($data)
1353 #======================================================================
1354 # VALUES, GENERATE, AUTOLOAD
1355 #======================================================================
1357 # LDNOTE: original code from nwiger, didn't touch code in that section
1358 # I feel the AUTOLOAD stuff should not be the default, it should
1359 # only be activated on explicit demand by user.
1363 my $data = shift || return;
1364 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1365 unless ref $data eq 'HASH';
1368 foreach my $k (sort keys %$data) {
1369 my $v = $data->{$k};
1370 $self->_SWITCH_refkind($v, {
1372 if ($self->{array_datatypes}) { # array datatype
1373 push @all_bind, $self->_bindtype($k, $v);
1375 else { # literal SQL with bind
1376 my ($sql, @bind) = @$v;
1377 $self->_assert_bindval_matches_bindtype(@bind);
1378 push @all_bind, @bind;
1381 ARRAYREFREF => sub { # literal SQL with bind
1382 my ($sql, @bind) = @${$v};
1383 $self->_assert_bindval_matches_bindtype(@bind);
1384 push @all_bind, @bind;
1386 SCALARREF => sub { # literal SQL without bind
1388 SCALAR_or_UNDEF => sub {
1389 push @all_bind, $self->_bindtype($k, $v);
1400 my(@sql, @sqlq, @sqlv);
1404 if ($ref eq 'HASH') {
1405 for my $k (sort keys %$_) {
1408 my $label = $self->_quote($k);
1409 if ($r eq 'ARRAY') {
1410 # literal SQL with bind
1411 my ($sql, @bind) = @$v;
1412 $self->_assert_bindval_matches_bindtype(@bind);
1413 push @sqlq, "$label = $sql";
1415 } elsif ($r eq 'SCALAR') {
1416 # literal SQL without bind
1417 push @sqlq, "$label = $$v";
1419 push @sqlq, "$label = ?";
1420 push @sqlv, $self->_bindtype($k, $v);
1423 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1424 } elsif ($ref eq 'ARRAY') {
1425 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1428 if ($r eq 'ARRAY') { # literal SQL with bind
1429 my ($sql, @bind) = @$v;
1430 $self->_assert_bindval_matches_bindtype(@bind);
1433 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1434 # embedded literal SQL
1441 push @sql, '(' . join(', ', @sqlq) . ')';
1442 } elsif ($ref eq 'SCALAR') {
1446 # strings get case twiddled
1447 push @sql, $self->_sqlcase($_);
1451 my $sql = join ' ', @sql;
1453 # this is pretty tricky
1454 # if ask for an array, return ($stmt, @bind)
1455 # otherwise, s/?/shift @sqlv/ to put it inline
1457 return ($sql, @sqlv);
1459 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1460 ref $d ? $d->[1] : $d/e;
1469 # This allows us to check for a local, then _form, attr
1471 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1472 return $self->generate($name, @_);
1483 SQL::Abstract - Generate SQL from Perl data structures
1489 my $sql = SQL::Abstract->new;
1491 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1493 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1495 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1497 my($stmt, @bind) = $sql->delete($table, \%where);
1499 # Then, use these in your DBI statements
1500 my $sth = $dbh->prepare($stmt);
1501 $sth->execute(@bind);
1503 # Just generate the WHERE clause
1504 my($stmt, @bind) = $sql->where(\%where, $order);
1506 # Return values in the same order, for hashed queries
1507 # See PERFORMANCE section for more details
1508 my @bind = $sql->values(\%fieldvals);
1512 This module was inspired by the excellent L<DBIx::Abstract>.
1513 However, in using that module I found that what I really wanted
1514 to do was generate SQL, but still retain complete control over my
1515 statement handles and use the DBI interface. So, I set out to
1516 create an abstract SQL generation module.
1518 While based on the concepts used by L<DBIx::Abstract>, there are
1519 several important differences, especially when it comes to WHERE
1520 clauses. I have modified the concepts used to make the SQL easier
1521 to generate from Perl data structures and, IMO, more intuitive.
1522 The underlying idea is for this module to do what you mean, based
1523 on the data structures you provide it. The big advantage is that
1524 you don't have to modify your code every time your data changes,
1525 as this module figures it out.
1527 To begin with, an SQL INSERT is as easy as just specifying a hash
1528 of C<key=value> pairs:
1531 name => 'Jimbo Bobson',
1532 phone => '123-456-7890',
1533 address => '42 Sister Lane',
1534 city => 'St. Louis',
1535 state => 'Louisiana',
1538 The SQL can then be generated with this:
1540 my($stmt, @bind) = $sql->insert('people', \%data);
1542 Which would give you something like this:
1544 $stmt = "INSERT INTO people
1545 (address, city, name, phone, state)
1546 VALUES (?, ?, ?, ?, ?)";
1547 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1548 '123-456-7890', 'Louisiana');
1550 These are then used directly in your DBI code:
1552 my $sth = $dbh->prepare($stmt);
1553 $sth->execute(@bind);
1555 =head2 Inserting and Updating Arrays
1557 If your database has array types (like for example Postgres),
1558 activate the special option C<< array_datatypes => 1 >>
1559 when creating the C<SQL::Abstract> object.
1560 Then you may use an arrayref to insert and update database array types:
1562 my $sql = SQL::Abstract->new(array_datatypes => 1);
1564 planets => [qw/Mercury Venus Earth Mars/]
1567 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1571 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1573 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1576 =head2 Inserting and Updating SQL
1578 In order to apply SQL functions to elements of your C<%data> you may
1579 specify a reference to an arrayref for the given hash value. For example,
1580 if you need to execute the Oracle C<to_date> function on a value, you can
1581 say something like this:
1585 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1588 The first value in the array is the actual SQL. Any other values are
1589 optional and would be included in the bind values array. This gives
1592 my($stmt, @bind) = $sql->insert('people', \%data);
1594 $stmt = "INSERT INTO people (name, date_entered)
1595 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1596 @bind = ('Bill', '03/02/2003');
1598 An UPDATE is just as easy, all you change is the name of the function:
1600 my($stmt, @bind) = $sql->update('people', \%data);
1602 Notice that your C<%data> isn't touched; the module will generate
1603 the appropriately quirky SQL for you automatically. Usually you'll
1604 want to specify a WHERE clause for your UPDATE, though, which is
1605 where handling C<%where> hashes comes in handy...
1607 =head2 Complex where statements
1609 This module can generate pretty complicated WHERE statements
1610 easily. For example, simple C<key=value> pairs are taken to mean
1611 equality, and if you want to see if a field is within a set
1612 of values, you can use an arrayref. Let's say we wanted to
1613 SELECT some data based on this criteria:
1616 requestor => 'inna',
1617 worker => ['nwiger', 'rcwe', 'sfz'],
1618 status => { '!=', 'completed' }
1621 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1623 The above would give you something like this:
1625 $stmt = "SELECT * FROM tickets WHERE
1626 ( requestor = ? ) AND ( status != ? )
1627 AND ( worker = ? OR worker = ? OR worker = ? )";
1628 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1630 Which you could then use in DBI code like so:
1632 my $sth = $dbh->prepare($stmt);
1633 $sth->execute(@bind);
1639 The methods are simple. There's one for every major SQL operation,
1640 and a constructor you use first. The arguments are specified in a
1641 similar order for each method (table, then fields, then a where
1642 clause) to try and simplify things.
1644 =head2 new(option => 'value')
1646 The C<new()> function takes a list of options and values, and returns
1647 a new B<SQL::Abstract> object which can then be used to generate SQL
1648 through the methods below. The options accepted are:
1654 If set to 'lower', then SQL will be generated in all lowercase. By
1655 default SQL is generated in "textbook" case meaning something like:
1657 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1659 Any setting other than 'lower' is ignored.
1663 This determines what the default comparison operator is. By default
1664 it is C<=>, meaning that a hash like this:
1666 %where = (name => 'nwiger', email => 'nate@wiger.org');
1668 Will generate SQL like this:
1670 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1672 However, you may want loose comparisons by default, so if you set
1673 C<cmp> to C<like> you would get SQL such as:
1675 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1677 You can also override the comparison on an individual basis - see
1678 the huge section on L</"WHERE CLAUSES"> at the bottom.
1680 =item sqltrue, sqlfalse
1682 Expressions for inserting boolean values within SQL statements.
1683 By default these are C<1=1> and C<1=0>. They are used
1684 by the special operators C<-in> and C<-not_in> for generating
1685 correct SQL even when the argument is an empty array (see below).
1689 This determines the default logical operator for multiple WHERE
1690 statements in arrays or hashes. If absent, the default logic is "or"
1691 for arrays, and "and" for hashes. This means that a WHERE
1695 event_date => {'>=', '2/13/99'},
1696 event_date => {'<=', '4/24/03'},
1699 will generate SQL like this:
1701 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1703 This is probably not what you want given this query, though (look
1704 at the dates). To change the "OR" to an "AND", simply specify:
1706 my $sql = SQL::Abstract->new(logic => 'and');
1708 Which will change the above C<WHERE> to:
1710 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1712 The logic can also be changed locally by inserting
1713 a modifier in front of an arrayref:
1715 @where = (-and => [event_date => {'>=', '2/13/99'},
1716 event_date => {'<=', '4/24/03'} ]);
1718 See the L</"WHERE CLAUSES"> section for explanations.
1722 This will automatically convert comparisons using the specified SQL
1723 function for both column and value. This is mostly used with an argument
1724 of C<upper> or C<lower>, so that the SQL will have the effect of
1725 case-insensitive "searches". For example, this:
1727 $sql = SQL::Abstract->new(convert => 'upper');
1728 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1730 Will turn out the following SQL:
1732 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1734 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1735 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1736 not validate this option; it will just pass through what you specify verbatim).
1740 This is a kludge because many databases suck. For example, you can't
1741 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1742 Instead, you have to use C<bind_param()>:
1744 $sth->bind_param(1, 'reg data');
1745 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1747 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1748 which loses track of which field each slot refers to. Fear not.
1750 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1751 Currently, you can specify either C<normal> (default) or C<columns>. If you
1752 specify C<columns>, you will get an array that looks like this:
1754 my $sql = SQL::Abstract->new(bindtype => 'columns');
1755 my($stmt, @bind) = $sql->insert(...);
1758 [ 'column1', 'value1' ],
1759 [ 'column2', 'value2' ],
1760 [ 'column3', 'value3' ],
1763 You can then iterate through this manually, using DBI's C<bind_param()>.
1765 $sth->prepare($stmt);
1768 my($col, $data) = @$_;
1769 if ($col eq 'details' || $col eq 'comments') {
1770 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1771 } elsif ($col eq 'image') {
1772 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1774 $sth->bind_param($i, $data);
1778 $sth->execute; # execute without @bind now
1780 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1781 Basically, the advantage is still that you don't have to care which fields
1782 are or are not included. You could wrap that above C<for> loop in a simple
1783 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1784 get a layer of abstraction over manual SQL specification.
1786 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1787 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1788 will expect the bind values in this format.
1792 This is the character that a table or column name will be quoted
1793 with. By default this is an empty string, but you could set it to
1794 the character C<`>, to generate SQL like this:
1796 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1798 Alternatively, you can supply an array ref of two items, the first being the left
1799 hand quote character, and the second the right hand quote character. For
1800 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1801 that generates SQL like this:
1803 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1805 Quoting is useful if you have tables or columns names that are reserved
1806 words in your database's SQL dialect.
1810 This is the character that will be used to escape L</quote_char>s appearing
1811 in an identifier before it has been quoted.
1813 The parameter default in case of a single L</quote_char> character is the quote
1816 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1817 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1818 of the B<opening (left)> L</quote_char> within the identifier are currently left
1819 untouched. The default for opening-closing-style quotes may change in future
1820 versions, thus you are B<strongly encouraged> to specify the escape character
1825 This is the character that separates a table and column name. It is
1826 necessary to specify this when the C<quote_char> option is selected,
1827 so that tables and column names can be individually quoted like this:
1829 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1831 =item injection_guard
1833 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1834 column name specified in a query structure. This is a safety mechanism to avoid
1835 injection attacks when mishandling user input e.g.:
1837 my %condition_as_column_value_pairs = get_values_from_user();
1838 $sqla->select( ... , \%condition_as_column_value_pairs );
1840 If the expression matches an exception is thrown. Note that literal SQL
1841 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1843 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1845 =item array_datatypes
1847 When this option is true, arrayrefs in INSERT or UPDATE are
1848 interpreted as array datatypes and are passed directly
1850 When this option is false, arrayrefs are interpreted
1851 as literal SQL, just like refs to arrayrefs
1852 (but this behavior is for backwards compatibility; when writing
1853 new queries, use the "reference to arrayref" syntax
1859 Takes a reference to a list of "special operators"
1860 to extend the syntax understood by L<SQL::Abstract>.
1861 See section L</"SPECIAL OPERATORS"> for details.
1865 Takes a reference to a list of "unary operators"
1866 to extend the syntax understood by L<SQL::Abstract>.
1867 See section L</"UNARY OPERATORS"> for details.
1873 =head2 insert($table, \@values || \%fieldvals, \%options)
1875 This is the simplest function. You simply give it a table name
1876 and either an arrayref of values or hashref of field/value pairs.
1877 It returns an SQL INSERT statement and a list of bind values.
1878 See the sections on L</"Inserting and Updating Arrays"> and
1879 L</"Inserting and Updating SQL"> for information on how to insert
1880 with those data types.
1882 The optional C<\%options> hash reference may contain additional
1883 options to generate the insert SQL. Currently supported options
1890 Takes either a scalar of raw SQL fields, or an array reference of
1891 field names, and adds on an SQL C<RETURNING> statement at the end.
1892 This allows you to return data generated by the insert statement
1893 (such as row IDs) without performing another C<SELECT> statement.
1894 Note, however, this is not part of the SQL standard and may not
1895 be supported by all database engines.
1899 =head2 update($table, \%fieldvals, \%where, \%options)
1901 This takes a table, hashref of field/value pairs, and an optional
1902 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1904 See the sections on L</"Inserting and Updating Arrays"> and
1905 L</"Inserting and Updating SQL"> for information on how to insert
1906 with those data types.
1908 The optional C<\%options> hash reference may contain additional
1909 options to generate the update SQL. Currently supported options
1916 See the C<returning> option to
1917 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1921 =head2 select($source, $fields, $where, $order)
1923 This returns a SQL SELECT statement and associated list of bind values, as
1924 specified by the arguments:
1930 Specification of the 'FROM' part of the statement.
1931 The argument can be either a plain scalar (interpreted as a table
1932 name, will be quoted), or an arrayref (interpreted as a list
1933 of table names, joined by commas, quoted), or a scalarref
1934 (literal SQL, not quoted).
1938 Specification of the list of fields to retrieve from
1940 The argument can be either an arrayref (interpreted as a list
1941 of field names, will be joined by commas and quoted), or a
1942 plain scalar (literal SQL, not quoted).
1943 Please observe that this API is not as flexible as that of
1944 the first argument C<$source>, for backwards compatibility reasons.
1948 Optional argument to specify the WHERE part of the query.
1949 The argument is most often a hashref, but can also be
1950 an arrayref or plain scalar --
1951 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1955 Optional argument to specify the ORDER BY part of the query.
1956 The argument can be a scalar, a hashref or an arrayref
1957 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1963 =head2 delete($table, \%where, \%options)
1965 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1966 It returns an SQL DELETE statement and list of bind values.
1968 The optional C<\%options> hash reference may contain additional
1969 options to generate the delete SQL. Currently supported options
1976 See the C<returning> option to
1977 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1981 =head2 where(\%where, $order)
1983 This is used to generate just the WHERE clause. For example,
1984 if you have an arbitrary data structure and know what the
1985 rest of your SQL is going to look like, but want an easy way
1986 to produce a WHERE clause, use this. It returns an SQL WHERE
1987 clause and list of bind values.
1990 =head2 values(\%data)
1992 This just returns the values from the hash C<%data>, in the same
1993 order that would be returned from any of the other above queries.
1994 Using this allows you to markedly speed up your queries if you
1995 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1997 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1999 Warning: This is an experimental method and subject to change.
2001 This returns arbitrarily generated SQL. It's a really basic shortcut.
2002 It will return two different things, depending on return context:
2004 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2005 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2007 These would return the following:
2009 # First calling form
2010 $stmt = "CREATE TABLE test (?, ?)";
2011 @bind = (field1, field2);
2013 # Second calling form
2014 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2016 Depending on what you're trying to do, it's up to you to choose the correct
2017 format. In this example, the second form is what you would want.
2021 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2025 ALTER SESSION SET nls_date_format = 'MM/YY'
2027 You get the idea. Strings get their case twiddled, but everything
2028 else remains verbatim.
2030 =head1 EXPORTABLE FUNCTIONS
2032 =head2 is_plain_value
2034 Determines if the supplied argument is a plain value as understood by this
2039 =item * The value is C<undef>
2041 =item * The value is a non-reference
2043 =item * The value is an object with stringification overloading
2045 =item * The value is of the form C<< { -value => $anything } >>
2049 On failure returns C<undef>, on success returns a B<scalar> reference
2050 to the original supplied argument.
2056 The stringification overloading detection is rather advanced: it takes
2057 into consideration not only the presence of a C<""> overload, but if that
2058 fails also checks for enabled
2059 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2060 on either C<0+> or C<bool>.
2062 Unfortunately testing in the field indicates that this
2063 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2064 but only when very large numbers of stringifying objects are involved.
2065 At the time of writing ( Sep 2014 ) there is no clear explanation of
2066 the direct cause, nor is there a manageably small test case that reliably
2067 reproduces the problem.
2069 If you encounter any of the following exceptions in B<random places within
2070 your application stack> - this module may be to blame:
2072 Operation "ne": no method found,
2073 left argument in overloaded package <something>,
2074 right argument in overloaded package <something>
2078 Stub found while resolving method "???" overloading """" in package <something>
2080 If you fall victim to the above - please attempt to reduce the problem
2081 to something that could be sent to the L<SQL::Abstract developers
2082 |DBIx::Class/GETTING HELP/SUPPORT>
2083 (either publicly or privately). As a workaround in the meantime you can
2084 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2085 value, which will most likely eliminate your problem (at the expense of
2086 not being able to properly detect exotic forms of stringification).
2088 This notice and environment variable will be removed in a future version,
2089 as soon as the underlying problem is found and a reliable workaround is
2094 =head2 is_literal_value
2096 Determines if the supplied argument is a literal value as understood by this
2101 =item * C<\$sql_string>
2103 =item * C<\[ $sql_string, @bind_values ]>
2107 On failure returns C<undef>, on success returns an B<array> reference
2108 containing the unpacked version of the supplied literal SQL and bind values.
2110 =head1 WHERE CLAUSES
2114 This module uses a variation on the idea from L<DBIx::Abstract>. It
2115 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2116 module is that things in arrays are OR'ed, and things in hashes
2119 The easiest way to explain is to show lots of examples. After
2120 each C<%where> hash shown, it is assumed you used:
2122 my($stmt, @bind) = $sql->where(\%where);
2124 However, note that the C<%where> hash can be used directly in any
2125 of the other functions as well, as described above.
2127 =head2 Key-value pairs
2129 So, let's get started. To begin, a simple hash:
2133 status => 'completed'
2136 Is converted to SQL C<key = val> statements:
2138 $stmt = "WHERE user = ? AND status = ?";
2139 @bind = ('nwiger', 'completed');
2141 One common thing I end up doing is having a list of values that
2142 a field can be in. To do this, simply specify a list inside of
2147 status => ['assigned', 'in-progress', 'pending'];
2150 This simple code will create the following:
2152 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2153 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2155 A field associated to an empty arrayref will be considered a
2156 logical false and will generate 0=1.
2158 =head2 Tests for NULL values
2160 If the value part is C<undef> then this is converted to SQL <IS NULL>
2169 $stmt = "WHERE user = ? AND status IS NULL";
2172 To test if a column IS NOT NULL:
2176 status => { '!=', undef },
2179 =head2 Specific comparison operators
2181 If you want to specify a different type of operator for your comparison,
2182 you can use a hashref for a given column:
2186 status => { '!=', 'completed' }
2189 Which would generate:
2191 $stmt = "WHERE user = ? AND status != ?";
2192 @bind = ('nwiger', 'completed');
2194 To test against multiple values, just enclose the values in an arrayref:
2196 status => { '=', ['assigned', 'in-progress', 'pending'] };
2198 Which would give you:
2200 "WHERE status = ? OR status = ? OR status = ?"
2203 The hashref can also contain multiple pairs, in which case it is expanded
2204 into an C<AND> of its elements:
2208 status => { '!=', 'completed', -not_like => 'pending%' }
2211 # Or more dynamically, like from a form
2212 $where{user} = 'nwiger';
2213 $where{status}{'!='} = 'completed';
2214 $where{status}{'-not_like'} = 'pending%';
2216 # Both generate this
2217 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2218 @bind = ('nwiger', 'completed', 'pending%');
2221 To get an OR instead, you can combine it with the arrayref idea:
2225 priority => [ { '=', 2 }, { '>', 5 } ]
2228 Which would generate:
2230 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2231 @bind = ('2', '5', 'nwiger');
2233 If you want to include literal SQL (with or without bind values), just use a
2234 scalar reference or reference to an arrayref as the value:
2237 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2238 date_expires => { '<' => \"now()" }
2241 Which would generate:
2243 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2244 @bind = ('11/26/2008');
2247 =head2 Logic and nesting operators
2249 In the example above,
2250 there is a subtle trap if you want to say something like
2251 this (notice the C<AND>):
2253 WHERE priority != ? AND priority != ?
2255 Because, in Perl you I<can't> do this:
2257 priority => { '!=' => 2, '!=' => 1 }
2259 As the second C<!=> key will obliterate the first. The solution
2260 is to use the special C<-modifier> form inside an arrayref:
2262 priority => [ -and => {'!=', 2},
2266 Normally, these would be joined by C<OR>, but the modifier tells it
2267 to use C<AND> instead. (Hint: You can use this in conjunction with the
2268 C<logic> option to C<new()> in order to change the way your queries
2269 work by default.) B<Important:> Note that the C<-modifier> goes
2270 B<INSIDE> the arrayref, as an extra first element. This will
2271 B<NOT> do what you think it might:
2273 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2275 Here is a quick list of equivalencies, since there is some overlap:
2278 status => {'!=', 'completed', 'not like', 'pending%' }
2279 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2282 status => {'=', ['assigned', 'in-progress']}
2283 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2284 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2288 =head2 Special operators: IN, BETWEEN, etc.
2290 You can also use the hashref format to compare a list of fields using the
2291 C<IN> comparison operator, by specifying the list as an arrayref:
2294 status => 'completed',
2295 reportid => { -in => [567, 2335, 2] }
2298 Which would generate:
2300 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2301 @bind = ('completed', '567', '2335', '2');
2303 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2306 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2307 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2308 'sqltrue' (by default: C<1=1>).
2310 In addition to the array you can supply a chunk of literal sql or
2311 literal sql with bind:
2314 customer => { -in => \[
2315 'SELECT cust_id FROM cust WHERE balance > ?',
2318 status => { -in => \'SELECT status_codes FROM states' },
2324 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2325 AND status IN ( SELECT status_codes FROM states )
2329 Finally, if the argument to C<-in> is not a reference, it will be
2330 treated as a single-element array.
2332 Another pair of operators is C<-between> and C<-not_between>,
2333 used with an arrayref of two values:
2337 completion_date => {
2338 -not_between => ['2002-10-01', '2003-02-06']
2344 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2346 Just like with C<-in> all plausible combinations of literal SQL
2350 start0 => { -between => [ 1, 2 ] },
2351 start1 => { -between => \["? AND ?", 1, 2] },
2352 start2 => { -between => \"lower(x) AND upper(y)" },
2353 start3 => { -between => [
2355 \["upper(?)", 'stuff' ],
2362 ( start0 BETWEEN ? AND ? )
2363 AND ( start1 BETWEEN ? AND ? )
2364 AND ( start2 BETWEEN lower(x) AND upper(y) )
2365 AND ( start3 BETWEEN lower(x) AND upper(?) )
2367 @bind = (1, 2, 1, 2, 'stuff');
2370 These are the two builtin "special operators"; but the
2371 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2373 =head2 Unary operators: bool
2375 If you wish to test against boolean columns or functions within your
2376 database you can use the C<-bool> and C<-not_bool> operators. For
2377 example to test the column C<is_user> being true and the column
2378 C<is_enabled> being false you would use:-
2382 -not_bool => 'is_enabled',
2387 WHERE is_user AND NOT is_enabled
2389 If a more complex combination is required, testing more conditions,
2390 then you should use the and/or operators:-
2395 -not_bool => { two=> { -rlike => 'bar' } },
2396 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2407 (NOT ( three = ? OR three > ? ))
2410 =head2 Nested conditions, -and/-or prefixes
2412 So far, we've seen how multiple conditions are joined with a top-level
2413 C<AND>. We can change this by putting the different conditions we want in
2414 hashes and then putting those hashes in an array. For example:
2419 status => { -like => ['pending%', 'dispatched'] },
2423 status => 'unassigned',
2427 This data structure would create the following:
2429 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2430 OR ( user = ? AND status = ? ) )";
2431 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2434 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2435 to change the logic inside:
2441 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2442 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2449 $stmt = "WHERE ( user = ?
2450 AND ( ( workhrs > ? AND geo = ? )
2451 OR ( workhrs < ? OR geo = ? ) ) )";
2452 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2454 =head3 Algebraic inconsistency, for historical reasons
2456 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2457 operator goes C<outside> of the nested structure; whereas when connecting
2458 several constraints on one column, the C<-and> operator goes
2459 C<inside> the arrayref. Here is an example combining both features:
2462 -and => [a => 1, b => 2],
2463 -or => [c => 3, d => 4],
2464 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2469 WHERE ( ( ( a = ? AND b = ? )
2470 OR ( c = ? OR d = ? )
2471 OR ( e LIKE ? AND e LIKE ? ) ) )
2473 This difference in syntax is unfortunate but must be preserved for
2474 historical reasons. So be careful: the two examples below would
2475 seem algebraically equivalent, but they are not
2478 { -like => 'foo%' },
2479 { -like => '%bar' },
2481 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2484 { col => { -like => 'foo%' } },
2485 { col => { -like => '%bar' } },
2487 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2490 =head2 Literal SQL and value type operators
2492 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2493 side" is a column name and the "right side" is a value (normally rendered as
2494 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2495 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2496 alter this behavior. There are several ways of doing so.
2500 This is a virtual operator that signals the string to its right side is an
2501 identifier (a column name) and not a value. For example to compare two
2502 columns you would write:
2505 priority => { '<', 2 },
2506 requestor => { -ident => 'submitter' },
2511 $stmt = "WHERE priority < ? AND requestor = submitter";
2514 If you are maintaining legacy code you may see a different construct as
2515 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2520 This is a virtual operator that signals that the construct to its right side
2521 is a value to be passed to DBI. This is for example necessary when you want
2522 to write a where clause against an array (for RDBMS that support such
2523 datatypes). For example:
2526 array => { -value => [1, 2, 3] }
2531 $stmt = 'WHERE array = ?';
2532 @bind = ([1, 2, 3]);
2534 Note that if you were to simply say:
2540 the result would probably not be what you wanted:
2542 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2547 Finally, sometimes only literal SQL will do. To include a random snippet
2548 of SQL verbatim, you specify it as a scalar reference. Consider this only
2549 as a last resort. Usually there is a better way. For example:
2552 priority => { '<', 2 },
2553 requestor => { -in => \'(SELECT name FROM hitmen)' },
2558 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2561 Note that in this example, you only get one bind parameter back, since
2562 the verbatim SQL is passed as part of the statement.
2566 Never use untrusted input as a literal SQL argument - this is a massive
2567 security risk (there is no way to check literal snippets for SQL
2568 injections and other nastyness). If you need to deal with untrusted input
2569 use literal SQL with placeholders as described next.
2571 =head3 Literal SQL with placeholders and bind values (subqueries)
2573 If the literal SQL to be inserted has placeholders and bind values,
2574 use a reference to an arrayref (yes this is a double reference --
2575 not so common, but perfectly legal Perl). For example, to find a date
2576 in Postgres you can use something like this:
2579 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2584 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2587 Note that you must pass the bind values in the same format as they are returned
2588 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2589 to C<columns>, you must provide the bind values in the
2590 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2591 scalar value; most commonly the column name, but you can use any scalar value
2592 (including references and blessed references), L<SQL::Abstract> will simply
2593 pass it through intact. So if C<bindtype> is set to C<columns> the above
2594 example will look like:
2597 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2600 Literal SQL is especially useful for nesting parenthesized clauses in the
2601 main SQL query. Here is a first example:
2603 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2607 bar => \["IN ($sub_stmt)" => @sub_bind],
2612 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2613 WHERE c2 < ? AND c3 LIKE ?))";
2614 @bind = (1234, 100, "foo%");
2616 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2617 are expressed in the same way. Of course the C<$sub_stmt> and
2618 its associated bind values can be generated through a former call
2621 my ($sub_stmt, @sub_bind)
2622 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2623 c3 => {-like => "foo%"}});
2626 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2629 In the examples above, the subquery was used as an operator on a column;
2630 but the same principle also applies for a clause within the main C<%where>
2631 hash, like an EXISTS subquery:
2633 my ($sub_stmt, @sub_bind)
2634 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2635 my %where = ( -and => [
2637 \["EXISTS ($sub_stmt)" => @sub_bind],
2642 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2643 WHERE c1 = ? AND c2 > t0.c0))";
2647 Observe that the condition on C<c2> in the subquery refers to
2648 column C<t0.c0> of the main query: this is I<not> a bind
2649 value, so we have to express it through a scalar ref.
2650 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2651 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2652 what we wanted here.
2654 Finally, here is an example where a subquery is used
2655 for expressing unary negation:
2657 my ($sub_stmt, @sub_bind)
2658 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2659 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2661 lname => {like => '%son%'},
2662 \["NOT ($sub_stmt)" => @sub_bind],
2667 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2668 @bind = ('%son%', 10, 20)
2670 =head3 Deprecated usage of Literal SQL
2672 Below are some examples of archaic use of literal SQL. It is shown only as
2673 reference for those who deal with legacy code. Each example has a much
2674 better, cleaner and safer alternative that users should opt for in new code.
2680 my %where = ( requestor => \'IS NOT NULL' )
2682 $stmt = "WHERE requestor IS NOT NULL"
2684 This used to be the way of generating NULL comparisons, before the handling
2685 of C<undef> got formalized. For new code please use the superior syntax as
2686 described in L</Tests for NULL values>.
2690 my %where = ( requestor => \'= submitter' )
2692 $stmt = "WHERE requestor = submitter"
2694 This used to be the only way to compare columns. Use the superior L</-ident>
2695 method for all new code. For example an identifier declared in such a way
2696 will be properly quoted if L</quote_char> is properly set, while the legacy
2697 form will remain as supplied.
2701 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2703 $stmt = "WHERE completed > ? AND is_ready"
2704 @bind = ('2012-12-21')
2706 Using an empty string literal used to be the only way to express a boolean.
2707 For all new code please use the much more readable
2708 L<-bool|/Unary operators: bool> operator.
2714 These pages could go on for a while, since the nesting of the data
2715 structures this module can handle are pretty much unlimited (the
2716 module implements the C<WHERE> expansion as a recursive function
2717 internally). Your best bet is to "play around" with the module a
2718 little to see how the data structures behave, and choose the best
2719 format for your data based on that.
2721 And of course, all the values above will probably be replaced with
2722 variables gotten from forms or the command line. After all, if you
2723 knew everything ahead of time, you wouldn't have to worry about
2724 dynamically-generating SQL and could just hardwire it into your
2727 =head1 ORDER BY CLAUSES
2729 Some functions take an order by clause. This can either be a scalar (just a
2730 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2731 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2734 Given | Will Generate
2735 ---------------------------------------------------------------
2737 'colA' | ORDER BY colA
2739 [qw/colA colB/] | ORDER BY colA, colB
2741 {-asc => 'colA'} | ORDER BY colA ASC
2743 {-desc => 'colB'} | ORDER BY colB DESC
2745 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2747 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2749 \'colA DESC' | ORDER BY colA DESC
2751 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2752 | /* ...with $x bound to ? */
2755 { -asc => 'colA' }, | colA ASC,
2756 { -desc => [qw/colB/] }, | colB DESC,
2757 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2758 \'colE DESC', | colE DESC,
2759 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2760 ] | /* ...with $x bound to ? */
2761 ===============================================================
2765 =head1 SPECIAL OPERATORS
2767 my $sqlmaker = SQL::Abstract->new(special_ops => [
2771 my ($self, $field, $op, $arg) = @_;
2777 handler => 'method_name',
2781 A "special operator" is a SQL syntactic clause that can be
2782 applied to a field, instead of a usual binary operator.
2785 WHERE field IN (?, ?, ?)
2786 WHERE field BETWEEN ? AND ?
2787 WHERE MATCH(field) AGAINST (?, ?)
2789 Special operators IN and BETWEEN are fairly standard and therefore
2790 are builtin within C<SQL::Abstract> (as the overridable methods
2791 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2792 like the MATCH .. AGAINST example above which is specific to MySQL,
2793 you can write your own operator handlers - supply a C<special_ops>
2794 argument to the C<new> method. That argument takes an arrayref of
2795 operator definitions; each operator definition is a hashref with two
2802 the regular expression to match the operator
2806 Either a coderef or a plain scalar method name. In both cases
2807 the expected return is C<< ($sql, @bind) >>.
2809 When supplied with a method name, it is simply called on the
2810 L<SQL::Abstract> object as:
2812 $self->$method_name($field, $op, $arg)
2816 $field is the LHS of the operator
2817 $op is the part that matched the handler regex
2820 When supplied with a coderef, it is called as:
2822 $coderef->($self, $field, $op, $arg)
2827 For example, here is an implementation
2828 of the MATCH .. AGAINST syntax for MySQL
2830 my $sqlmaker = SQL::Abstract->new(special_ops => [
2832 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2833 {regex => qr/^match$/i,
2835 my ($self, $field, $op, $arg) = @_;
2836 $arg = [$arg] if not ref $arg;
2837 my $label = $self->_quote($field);
2838 my ($placeholder) = $self->_convert('?');
2839 my $placeholders = join ", ", (($placeholder) x @$arg);
2840 my $sql = $self->_sqlcase('match') . " ($label) "
2841 . $self->_sqlcase('against') . " ($placeholders) ";
2842 my @bind = $self->_bindtype($field, @$arg);
2843 return ($sql, @bind);
2850 =head1 UNARY OPERATORS
2852 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2856 my ($self, $op, $arg) = @_;
2862 handler => 'method_name',
2866 A "unary operator" is a SQL syntactic clause that can be
2867 applied to a field - the operator goes before the field
2869 You can write your own operator handlers - supply a C<unary_ops>
2870 argument to the C<new> method. That argument takes an arrayref of
2871 operator definitions; each operator definition is a hashref with two
2878 the regular expression to match the operator
2882 Either a coderef or a plain scalar method name. In both cases
2883 the expected return is C<< $sql >>.
2885 When supplied with a method name, it is simply called on the
2886 L<SQL::Abstract> object as:
2888 $self->$method_name($op, $arg)
2892 $op is the part that matched the handler regex
2893 $arg is the RHS or argument of the operator
2895 When supplied with a coderef, it is called as:
2897 $coderef->($self, $op, $arg)
2905 Thanks to some benchmarking by Mark Stosberg, it turns out that
2906 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2907 I must admit this wasn't an intentional design issue, but it's a
2908 byproduct of the fact that you get to control your C<DBI> handles
2911 To maximize performance, use a code snippet like the following:
2913 # prepare a statement handle using the first row
2914 # and then reuse it for the rest of the rows
2916 for my $href (@array_of_hashrefs) {
2917 $stmt ||= $sql->insert('table', $href);
2918 $sth ||= $dbh->prepare($stmt);
2919 $sth->execute($sql->values($href));
2922 The reason this works is because the keys in your C<$href> are sorted
2923 internally by B<SQL::Abstract>. Thus, as long as your data retains
2924 the same structure, you only have to generate the SQL the first time
2925 around. On subsequent queries, simply use the C<values> function provided
2926 by this module to return your values in the correct order.
2928 However this depends on the values having the same type - if, for
2929 example, the values of a where clause may either have values
2930 (resulting in sql of the form C<column = ?> with a single bind
2931 value), or alternatively the values might be C<undef> (resulting in
2932 sql of the form C<column IS NULL> with no bind value) then the
2933 caching technique suggested will not work.
2937 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2938 really like this part (I do, at least). Building up a complex query
2939 can be as simple as the following:
2946 use CGI::FormBuilder;
2949 my $form = CGI::FormBuilder->new(...);
2950 my $sql = SQL::Abstract->new;
2952 if ($form->submitted) {
2953 my $field = $form->field;
2954 my $id = delete $field->{id};
2955 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2958 Of course, you would still have to connect using C<DBI> to run the
2959 query, but the point is that if you make your form look like your
2960 table, the actual query script can be extremely simplistic.
2962 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2963 a fast interface to returning and formatting data. I frequently
2964 use these three modules together to write complex database query
2965 apps in under 50 lines.
2967 =head1 HOW TO CONTRIBUTE
2969 Contributions are always welcome, in all usable forms (we especially
2970 welcome documentation improvements). The delivery methods include git-
2971 or unified-diff formatted patches, GitHub pull requests, or plain bug
2972 reports either via RT or the Mailing list. Contributors are generally
2973 granted full access to the official repository after their first several
2974 patches pass successful review.
2976 This project is maintained in a git repository. The code and related tools are
2977 accessible at the following locations:
2981 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2983 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2985 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2987 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2993 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2994 Great care has been taken to preserve the I<published> behavior
2995 documented in previous versions in the 1.* family; however,
2996 some features that were previously undocumented, or behaved
2997 differently from the documentation, had to be changed in order
2998 to clarify the semantics. Hence, client code that was relying
2999 on some dark areas of C<SQL::Abstract> v1.*
3000 B<might behave differently> in v1.50.
3002 The main changes are:
3008 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3012 support for the { operator => \"..." } construct (to embed literal SQL)
3016 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3020 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3024 defensive programming: check arguments
3028 fixed bug with global logic, which was previously implemented
3029 through global variables yielding side-effects. Prior versions would
3030 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3031 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3032 Now this is interpreted
3033 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3038 fixed semantics of _bindtype on array args
3042 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3043 we just avoid shifting arrays within that tree.
3047 dropped the C<_modlogic> function
3051 =head1 ACKNOWLEDGEMENTS
3053 There are a number of individuals that have really helped out with
3054 this module. Unfortunately, most of them submitted bugs via CPAN
3055 so I have no idea who they are! But the people I do know are:
3057 Ash Berlin (order_by hash term support)
3058 Matt Trout (DBIx::Class support)
3059 Mark Stosberg (benchmarking)
3060 Chas Owens (initial "IN" operator support)
3061 Philip Collins (per-field SQL functions)
3062 Eric Kolve (hashref "AND" support)
3063 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3064 Dan Kubb (support for "quote_char" and "name_sep")
3065 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3066 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3067 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3068 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3069 Oliver Charles (support for "RETURNING" after "INSERT")
3075 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3079 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3081 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3083 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3084 While not an official support venue, C<DBIx::Class> makes heavy use of
3085 C<SQL::Abstract>, and as such list members there are very familiar with
3086 how to create queries.
3090 This module is free software; you may copy this under the same
3091 terms as perl itself (either the GNU General Public License or
3092 the Artistic License)