1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.87';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 if ($class->isa('DBIx::Class::SQLMaker')) {
164 push @{$opt{special_ops}}, our $DBIC_Compat_Op ||= {
165 regex => qr/^(?:ident|value)$/i, handler => sub { die "NOPE" }
167 $opt{is_dbic_sqlmaker} = 1;
171 $opt{unary_ops} ||= [];
173 # rudimentary sanity-check for user supplied bits treated as functions/operators
174 # If a purported function matches this regular expression, an exception is thrown.
175 # Literal SQL is *NOT* subject to this check, only functions (and column names
176 # when quoting is not in effect)
179 # need to guard against ()'s in column names too, but this will break tons of
180 # hacks... ideas anyone?
181 $opt{injection_guard} ||= qr/
187 $opt{node_types} = +{
188 map +("-$_" => '_render_'.$_),
189 qw(op func value 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 +{ $d => $expr };
563 if (my $m = our $Cur_Col_Meta) {
564 return +{ -bind => [ $m, $expr ] };
566 return +{ -value => $expr };
571 sub _expand_expr_hashpair {
572 my ($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' and my $m = our $Cur_Col_Meta) {
643 return +{ -bind => [ $m, $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 { -literal => [ '' ] } 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($ident));
925 my ($self, $value) = @_;
927 return ($self->_convert('?'), $self->_bindtype(undef, $value));
930 my %unop_postfix = map +($_ => 1),
931 'is null', 'is not null',
939 my ($self, $args) = @_;
940 my ($left, $low, $high) = @$args;
941 my ($rhsql, @rhbind) = do {
943 puke "Single arg to between must be a literal"
944 unless $low->{-literal};
947 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
948 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
949 @{$l}[1..$#$l], @{$h}[1..$#$h])
952 my ($lhsql, @lhbind) = $self->_render_expr($left);
954 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
958 }), 'between', 'not between'),
962 my ($self, $args) = @_;
963 my ($lhs, $rhs) = @$args;
966 my ($sql, @bind) = $self->_render_expr($_);
967 push @in_bind, @bind;
970 my ($lhsql, @lbind) = $self->_render_expr($lhs);
972 $lhsql.' '.$self->_sqlcase($op).' ( '
983 my ($op, @args) = @$v;
984 $op =~ s/^-// if length($op) > 1;
986 if (my $h = $special{$op}) {
987 return $self->$h(\@args);
989 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
990 if ($us and @args > 1) {
991 puke "Special op '${op}' requires first value to be identifier"
992 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
993 local our $Expand_Depth = 1;
994 return $self->${\($us->{handler})}($k, $op, $args[1]);
996 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
997 return $self->${\($us->{handler})}($op, $args[0]);
999 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1000 if (@args == 1 and $op !~ /^(and|or)$/) {
1001 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
1002 my $op_sql = $self->_sqlcase($final_op);
1004 $unop_postfix{lc($final_op)}
1005 ? "${expr_sql} ${op_sql}"
1006 : "${op_sql} ${expr_sql}"
1008 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1009 #} elsif (@args == 0) {
1012 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @args;
1013 return '' unless @parts;
1014 my $is_andor = !!($op =~ /^(and|or)$/);
1015 return @{$parts[0]} if $is_andor and @parts == 1;
1016 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1017 ' '.$self->_sqlcase($final_op).' ',
1022 map @{$_}[1..$#$_], @parts
1029 my ($self, $list) = @_;
1030 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @$list;
1031 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1035 my ($self, $rest) = @_;
1036 my ($func, @args) = @$rest;
1040 push @arg_sql, shift @x;
1042 } map [ $self->_render_expr($_) ], @args;
1043 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1047 my ($self, $bind) = @_;
1048 return ($self->_convert('?'), $self->_bindtype(@$bind));
1051 sub _render_literal {
1052 my ($self, $literal) = @_;
1053 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1057 # Some databases (SQLite) treat col IN (1, 2) different from
1058 # col IN ( (1, 2) ). Use this to strip all outer parens while
1059 # adding them back in the corresponding method
1060 sub _open_outer_paren {
1061 my ($self, $sql) = @_;
1063 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1065 # there are closing parens inside, need the heavy duty machinery
1066 # to reevaluate the extraction starting from $sql (full reevaluation)
1067 if ($inner =~ /\)/) {
1068 require Text::Balanced;
1070 my (undef, $remainder) = do {
1071 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1073 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1076 # the entire expression needs to be a balanced bracketed thing
1077 # (after an extract no remainder sans trailing space)
1078 last if defined $remainder and $remainder =~ /\S/;
1088 #======================================================================
1090 #======================================================================
1092 sub _expand_order_by {
1093 my ($self, $arg) = @_;
1095 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1097 my $expander = sub {
1098 my ($self, $dir, $expr) = @_;
1099 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1100 foreach my $arg (@to_expand) {
1104 and grep /^-(asc|desc)$/, keys %$arg
1106 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1109 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1110 map $self->_expand_expr($_, undef, -ident),
1111 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1112 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1115 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1116 sub { shift->$expander(asc => @_) },
1117 sub { shift->$expander(desc => @_) },
1120 return $self->$expander(undef, $arg);
1124 my ($self, $arg) = @_;
1126 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1128 my ($sql, @bind) = $self->_render_expr($expanded);
1130 return '' unless length($sql);
1132 my $final_sql = $self->_sqlcase(' order by ').$sql;
1134 return wantarray ? ($final_sql, @bind) : $final_sql;
1137 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1139 sub _order_by_chunks {
1140 my ($self, $arg) = @_;
1142 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1144 return $self->_chunkify_order_by($expanded);
1147 sub _chunkify_order_by {
1148 my ($self, $expanded) = @_;
1150 return grep length, $self->_render_expr($expanded)
1151 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1154 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1155 return map $self->_chunkify_order_by($_), @$l;
1157 return [ $self->_render_expr($_) ];
1161 #======================================================================
1162 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1163 #======================================================================
1168 ($self->_render_expr(
1169 $self->_expand_maybe_list_expr($from, undef, -ident)
1174 #======================================================================
1176 #======================================================================
1178 sub _expand_maybe_list_expr {
1179 my ($self, $expr, $logic, $default) = @_;
1181 if (ref($expr) eq 'ARRAY') {
1183 map $self->_expand_expr($_, $logic, $default), @$expr
1190 return $self->_expand_expr($e, $logic, $default);
1193 # highly optimized, as it's called way too often
1195 # my ($self, $label) = @_;
1197 return '' unless defined $_[1];
1198 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1199 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1201 unless ($_[0]->{quote_char}) {
1202 if (ref($_[1]) eq 'ARRAY') {
1203 return join($_[0]->{name_sep}||'.', @{$_[1]});
1205 $_[0]->_assert_pass_injection_guard($_[1]);
1210 my $qref = ref $_[0]->{quote_char};
1212 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1213 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1214 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1216 my $esc = $_[0]->{escape_char} || $r;
1218 # parts containing * are naturally unquoted
1220 $_[0]->{name_sep}||'',
1224 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1226 (ref($_[1]) eq 'ARRAY'
1230 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1238 # Conversion, if applicable
1240 #my ($self, $arg) = @_;
1241 if ($_[0]->{convert_where}) {
1242 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1249 #my ($self, $col, @vals) = @_;
1250 # called often - tighten code
1251 return $_[0]->{bindtype} eq 'columns'
1252 ? map {[$_[1], $_]} @_[2 .. $#_]
1257 # Dies if any element of @bind is not in [colname => value] format
1258 # if bindtype is 'columns'.
1259 sub _assert_bindval_matches_bindtype {
1260 # my ($self, @bind) = @_;
1262 if ($self->{bindtype} eq 'columns') {
1264 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1265 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1271 sub _join_sql_clauses {
1272 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1274 if (@$clauses_aref > 1) {
1275 my $join = " " . $self->_sqlcase($logic) . " ";
1276 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1277 return ($sql, @$bind_aref);
1279 elsif (@$clauses_aref) {
1280 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1283 return (); # if no SQL, ignore @$bind_aref
1288 # Fix SQL case, if so requested
1290 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1291 # don't touch the argument ... crooked logic, but let's not change it!
1292 return $_[0]->{case} ? $_[1] : uc($_[1]);
1296 #======================================================================
1297 # DISPATCHING FROM REFKIND
1298 #======================================================================
1301 my ($self, $data) = @_;
1303 return 'UNDEF' unless defined $data;
1305 # blessed objects are treated like scalars
1306 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1308 return 'SCALAR' unless $ref;
1311 while ($ref eq 'REF') {
1313 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1317 return ($ref||'SCALAR') . ('REF' x $n_steps);
1321 my ($self, $data) = @_;
1322 my @try = ($self->_refkind($data));
1323 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1324 push @try, 'FALLBACK';
1328 sub _METHOD_FOR_refkind {
1329 my ($self, $meth_prefix, $data) = @_;
1332 for (@{$self->_try_refkind($data)}) {
1333 $method = $self->can($meth_prefix."_".$_)
1337 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1341 sub _SWITCH_refkind {
1342 my ($self, $data, $dispatch_table) = @_;
1345 for (@{$self->_try_refkind($data)}) {
1346 $coderef = $dispatch_table->{$_}
1350 puke "no dispatch entry for ".$self->_refkind($data)
1359 #======================================================================
1360 # VALUES, GENERATE, AUTOLOAD
1361 #======================================================================
1363 # LDNOTE: original code from nwiger, didn't touch code in that section
1364 # I feel the AUTOLOAD stuff should not be the default, it should
1365 # only be activated on explicit demand by user.
1369 my $data = shift || return;
1370 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1371 unless ref $data eq 'HASH';
1374 foreach my $k (sort keys %$data) {
1375 my $v = $data->{$k};
1376 $self->_SWITCH_refkind($v, {
1378 if ($self->{array_datatypes}) { # array datatype
1379 push @all_bind, $self->_bindtype($k, $v);
1381 else { # literal SQL with bind
1382 my ($sql, @bind) = @$v;
1383 $self->_assert_bindval_matches_bindtype(@bind);
1384 push @all_bind, @bind;
1387 ARRAYREFREF => sub { # literal SQL with bind
1388 my ($sql, @bind) = @${$v};
1389 $self->_assert_bindval_matches_bindtype(@bind);
1390 push @all_bind, @bind;
1392 SCALARREF => sub { # literal SQL without bind
1394 SCALAR_or_UNDEF => sub {
1395 push @all_bind, $self->_bindtype($k, $v);
1406 my(@sql, @sqlq, @sqlv);
1410 if ($ref eq 'HASH') {
1411 for my $k (sort keys %$_) {
1414 my $label = $self->_quote($k);
1415 if ($r eq 'ARRAY') {
1416 # literal SQL with bind
1417 my ($sql, @bind) = @$v;
1418 $self->_assert_bindval_matches_bindtype(@bind);
1419 push @sqlq, "$label = $sql";
1421 } elsif ($r eq 'SCALAR') {
1422 # literal SQL without bind
1423 push @sqlq, "$label = $$v";
1425 push @sqlq, "$label = ?";
1426 push @sqlv, $self->_bindtype($k, $v);
1429 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1430 } elsif ($ref eq 'ARRAY') {
1431 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1434 if ($r eq 'ARRAY') { # literal SQL with bind
1435 my ($sql, @bind) = @$v;
1436 $self->_assert_bindval_matches_bindtype(@bind);
1439 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1440 # embedded literal SQL
1447 push @sql, '(' . join(', ', @sqlq) . ')';
1448 } elsif ($ref eq 'SCALAR') {
1452 # strings get case twiddled
1453 push @sql, $self->_sqlcase($_);
1457 my $sql = join ' ', @sql;
1459 # this is pretty tricky
1460 # if ask for an array, return ($stmt, @bind)
1461 # otherwise, s/?/shift @sqlv/ to put it inline
1463 return ($sql, @sqlv);
1465 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1466 ref $d ? $d->[1] : $d/e;
1475 # This allows us to check for a local, then _form, attr
1477 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1478 return $self->generate($name, @_);
1489 SQL::Abstract - Generate SQL from Perl data structures
1495 my $sql = SQL::Abstract->new;
1497 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1499 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1501 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1503 my($stmt, @bind) = $sql->delete($table, \%where);
1505 # Then, use these in your DBI statements
1506 my $sth = $dbh->prepare($stmt);
1507 $sth->execute(@bind);
1509 # Just generate the WHERE clause
1510 my($stmt, @bind) = $sql->where(\%where, $order);
1512 # Return values in the same order, for hashed queries
1513 # See PERFORMANCE section for more details
1514 my @bind = $sql->values(\%fieldvals);
1518 This module was inspired by the excellent L<DBIx::Abstract>.
1519 However, in using that module I found that what I really wanted
1520 to do was generate SQL, but still retain complete control over my
1521 statement handles and use the DBI interface. So, I set out to
1522 create an abstract SQL generation module.
1524 While based on the concepts used by L<DBIx::Abstract>, there are
1525 several important differences, especially when it comes to WHERE
1526 clauses. I have modified the concepts used to make the SQL easier
1527 to generate from Perl data structures and, IMO, more intuitive.
1528 The underlying idea is for this module to do what you mean, based
1529 on the data structures you provide it. The big advantage is that
1530 you don't have to modify your code every time your data changes,
1531 as this module figures it out.
1533 To begin with, an SQL INSERT is as easy as just specifying a hash
1534 of C<key=value> pairs:
1537 name => 'Jimbo Bobson',
1538 phone => '123-456-7890',
1539 address => '42 Sister Lane',
1540 city => 'St. Louis',
1541 state => 'Louisiana',
1544 The SQL can then be generated with this:
1546 my($stmt, @bind) = $sql->insert('people', \%data);
1548 Which would give you something like this:
1550 $stmt = "INSERT INTO people
1551 (address, city, name, phone, state)
1552 VALUES (?, ?, ?, ?, ?)";
1553 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1554 '123-456-7890', 'Louisiana');
1556 These are then used directly in your DBI code:
1558 my $sth = $dbh->prepare($stmt);
1559 $sth->execute(@bind);
1561 =head2 Inserting and Updating Arrays
1563 If your database has array types (like for example Postgres),
1564 activate the special option C<< array_datatypes => 1 >>
1565 when creating the C<SQL::Abstract> object.
1566 Then you may use an arrayref to insert and update database array types:
1568 my $sql = SQL::Abstract->new(array_datatypes => 1);
1570 planets => [qw/Mercury Venus Earth Mars/]
1573 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1577 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1579 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1582 =head2 Inserting and Updating SQL
1584 In order to apply SQL functions to elements of your C<%data> you may
1585 specify a reference to an arrayref for the given hash value. For example,
1586 if you need to execute the Oracle C<to_date> function on a value, you can
1587 say something like this:
1591 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1594 The first value in the array is the actual SQL. Any other values are
1595 optional and would be included in the bind values array. This gives
1598 my($stmt, @bind) = $sql->insert('people', \%data);
1600 $stmt = "INSERT INTO people (name, date_entered)
1601 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1602 @bind = ('Bill', '03/02/2003');
1604 An UPDATE is just as easy, all you change is the name of the function:
1606 my($stmt, @bind) = $sql->update('people', \%data);
1608 Notice that your C<%data> isn't touched; the module will generate
1609 the appropriately quirky SQL for you automatically. Usually you'll
1610 want to specify a WHERE clause for your UPDATE, though, which is
1611 where handling C<%where> hashes comes in handy...
1613 =head2 Complex where statements
1615 This module can generate pretty complicated WHERE statements
1616 easily. For example, simple C<key=value> pairs are taken to mean
1617 equality, and if you want to see if a field is within a set
1618 of values, you can use an arrayref. Let's say we wanted to
1619 SELECT some data based on this criteria:
1622 requestor => 'inna',
1623 worker => ['nwiger', 'rcwe', 'sfz'],
1624 status => { '!=', 'completed' }
1627 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1629 The above would give you something like this:
1631 $stmt = "SELECT * FROM tickets WHERE
1632 ( requestor = ? ) AND ( status != ? )
1633 AND ( worker = ? OR worker = ? OR worker = ? )";
1634 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1636 Which you could then use in DBI code like so:
1638 my $sth = $dbh->prepare($stmt);
1639 $sth->execute(@bind);
1645 The methods are simple. There's one for every major SQL operation,
1646 and a constructor you use first. The arguments are specified in a
1647 similar order for each method (table, then fields, then a where
1648 clause) to try and simplify things.
1650 =head2 new(option => 'value')
1652 The C<new()> function takes a list of options and values, and returns
1653 a new B<SQL::Abstract> object which can then be used to generate SQL
1654 through the methods below. The options accepted are:
1660 If set to 'lower', then SQL will be generated in all lowercase. By
1661 default SQL is generated in "textbook" case meaning something like:
1663 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1665 Any setting other than 'lower' is ignored.
1669 This determines what the default comparison operator is. By default
1670 it is C<=>, meaning that a hash like this:
1672 %where = (name => 'nwiger', email => 'nate@wiger.org');
1674 Will generate SQL like this:
1676 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1678 However, you may want loose comparisons by default, so if you set
1679 C<cmp> to C<like> you would get SQL such as:
1681 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1683 You can also override the comparison on an individual basis - see
1684 the huge section on L</"WHERE CLAUSES"> at the bottom.
1686 =item sqltrue, sqlfalse
1688 Expressions for inserting boolean values within SQL statements.
1689 By default these are C<1=1> and C<1=0>. They are used
1690 by the special operators C<-in> and C<-not_in> for generating
1691 correct SQL even when the argument is an empty array (see below).
1695 This determines the default logical operator for multiple WHERE
1696 statements in arrays or hashes. If absent, the default logic is "or"
1697 for arrays, and "and" for hashes. This means that a WHERE
1701 event_date => {'>=', '2/13/99'},
1702 event_date => {'<=', '4/24/03'},
1705 will generate SQL like this:
1707 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1709 This is probably not what you want given this query, though (look
1710 at the dates). To change the "OR" to an "AND", simply specify:
1712 my $sql = SQL::Abstract->new(logic => 'and');
1714 Which will change the above C<WHERE> to:
1716 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1718 The logic can also be changed locally by inserting
1719 a modifier in front of an arrayref:
1721 @where = (-and => [event_date => {'>=', '2/13/99'},
1722 event_date => {'<=', '4/24/03'} ]);
1724 See the L</"WHERE CLAUSES"> section for explanations.
1728 This will automatically convert comparisons using the specified SQL
1729 function for both column and value. This is mostly used with an argument
1730 of C<upper> or C<lower>, so that the SQL will have the effect of
1731 case-insensitive "searches". For example, this:
1733 $sql = SQL::Abstract->new(convert => 'upper');
1734 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1736 Will turn out the following SQL:
1738 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1740 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1741 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1742 not validate this option; it will just pass through what you specify verbatim).
1746 This is a kludge because many databases suck. For example, you can't
1747 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1748 Instead, you have to use C<bind_param()>:
1750 $sth->bind_param(1, 'reg data');
1751 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1753 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1754 which loses track of which field each slot refers to. Fear not.
1756 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1757 Currently, you can specify either C<normal> (default) or C<columns>. If you
1758 specify C<columns>, you will get an array that looks like this:
1760 my $sql = SQL::Abstract->new(bindtype => 'columns');
1761 my($stmt, @bind) = $sql->insert(...);
1764 [ 'column1', 'value1' ],
1765 [ 'column2', 'value2' ],
1766 [ 'column3', 'value3' ],
1769 You can then iterate through this manually, using DBI's C<bind_param()>.
1771 $sth->prepare($stmt);
1774 my($col, $data) = @$_;
1775 if ($col eq 'details' || $col eq 'comments') {
1776 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1777 } elsif ($col eq 'image') {
1778 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1780 $sth->bind_param($i, $data);
1784 $sth->execute; # execute without @bind now
1786 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1787 Basically, the advantage is still that you don't have to care which fields
1788 are or are not included. You could wrap that above C<for> loop in a simple
1789 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1790 get a layer of abstraction over manual SQL specification.
1792 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1793 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1794 will expect the bind values in this format.
1798 This is the character that a table or column name will be quoted
1799 with. By default this is an empty string, but you could set it to
1800 the character C<`>, to generate SQL like this:
1802 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1804 Alternatively, you can supply an array ref of two items, the first being the left
1805 hand quote character, and the second the right hand quote character. For
1806 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1807 that generates SQL like this:
1809 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1811 Quoting is useful if you have tables or columns names that are reserved
1812 words in your database's SQL dialect.
1816 This is the character that will be used to escape L</quote_char>s appearing
1817 in an identifier before it has been quoted.
1819 The parameter default in case of a single L</quote_char> character is the quote
1822 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1823 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1824 of the B<opening (left)> L</quote_char> within the identifier are currently left
1825 untouched. The default for opening-closing-style quotes may change in future
1826 versions, thus you are B<strongly encouraged> to specify the escape character
1831 This is the character that separates a table and column name. It is
1832 necessary to specify this when the C<quote_char> option is selected,
1833 so that tables and column names can be individually quoted like this:
1835 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1837 =item injection_guard
1839 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1840 column name specified in a query structure. This is a safety mechanism to avoid
1841 injection attacks when mishandling user input e.g.:
1843 my %condition_as_column_value_pairs = get_values_from_user();
1844 $sqla->select( ... , \%condition_as_column_value_pairs );
1846 If the expression matches an exception is thrown. Note that literal SQL
1847 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1849 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1851 =item array_datatypes
1853 When this option is true, arrayrefs in INSERT or UPDATE are
1854 interpreted as array datatypes and are passed directly
1856 When this option is false, arrayrefs are interpreted
1857 as literal SQL, just like refs to arrayrefs
1858 (but this behavior is for backwards compatibility; when writing
1859 new queries, use the "reference to arrayref" syntax
1865 Takes a reference to a list of "special operators"
1866 to extend the syntax understood by L<SQL::Abstract>.
1867 See section L</"SPECIAL OPERATORS"> for details.
1871 Takes a reference to a list of "unary operators"
1872 to extend the syntax understood by L<SQL::Abstract>.
1873 See section L</"UNARY OPERATORS"> for details.
1879 =head2 insert($table, \@values || \%fieldvals, \%options)
1881 This is the simplest function. You simply give it a table name
1882 and either an arrayref of values or hashref of field/value pairs.
1883 It returns an SQL INSERT statement and a list of bind values.
1884 See the sections on L</"Inserting and Updating Arrays"> and
1885 L</"Inserting and Updating SQL"> for information on how to insert
1886 with those data types.
1888 The optional C<\%options> hash reference may contain additional
1889 options to generate the insert SQL. Currently supported options
1896 Takes either a scalar of raw SQL fields, or an array reference of
1897 field names, and adds on an SQL C<RETURNING> statement at the end.
1898 This allows you to return data generated by the insert statement
1899 (such as row IDs) without performing another C<SELECT> statement.
1900 Note, however, this is not part of the SQL standard and may not
1901 be supported by all database engines.
1905 =head2 update($table, \%fieldvals, \%where, \%options)
1907 This takes a table, hashref of field/value pairs, and an optional
1908 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1910 See the sections on L</"Inserting and Updating Arrays"> and
1911 L</"Inserting and Updating SQL"> for information on how to insert
1912 with those data types.
1914 The optional C<\%options> hash reference may contain additional
1915 options to generate the update SQL. Currently supported options
1922 See the C<returning> option to
1923 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1927 =head2 select($source, $fields, $where, $order)
1929 This returns a SQL SELECT statement and associated list of bind values, as
1930 specified by the arguments:
1936 Specification of the 'FROM' part of the statement.
1937 The argument can be either a plain scalar (interpreted as a table
1938 name, will be quoted), or an arrayref (interpreted as a list
1939 of table names, joined by commas, quoted), or a scalarref
1940 (literal SQL, not quoted).
1944 Specification of the list of fields to retrieve from
1946 The argument can be either an arrayref (interpreted as a list
1947 of field names, will be joined by commas and quoted), or a
1948 plain scalar (literal SQL, not quoted).
1949 Please observe that this API is not as flexible as that of
1950 the first argument C<$source>, for backwards compatibility reasons.
1954 Optional argument to specify the WHERE part of the query.
1955 The argument is most often a hashref, but can also be
1956 an arrayref or plain scalar --
1957 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1961 Optional argument to specify the ORDER BY part of the query.
1962 The argument can be a scalar, a hashref or an arrayref
1963 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1969 =head2 delete($table, \%where, \%options)
1971 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1972 It returns an SQL DELETE statement and list of bind values.
1974 The optional C<\%options> hash reference may contain additional
1975 options to generate the delete SQL. Currently supported options
1982 See the C<returning> option to
1983 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1987 =head2 where(\%where, $order)
1989 This is used to generate just the WHERE clause. For example,
1990 if you have an arbitrary data structure and know what the
1991 rest of your SQL is going to look like, but want an easy way
1992 to produce a WHERE clause, use this. It returns an SQL WHERE
1993 clause and list of bind values.
1996 =head2 values(\%data)
1998 This just returns the values from the hash C<%data>, in the same
1999 order that would be returned from any of the other above queries.
2000 Using this allows you to markedly speed up your queries if you
2001 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2003 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2005 Warning: This is an experimental method and subject to change.
2007 This returns arbitrarily generated SQL. It's a really basic shortcut.
2008 It will return two different things, depending on return context:
2010 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2011 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2013 These would return the following:
2015 # First calling form
2016 $stmt = "CREATE TABLE test (?, ?)";
2017 @bind = (field1, field2);
2019 # Second calling form
2020 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2022 Depending on what you're trying to do, it's up to you to choose the correct
2023 format. In this example, the second form is what you would want.
2027 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2031 ALTER SESSION SET nls_date_format = 'MM/YY'
2033 You get the idea. Strings get their case twiddled, but everything
2034 else remains verbatim.
2036 =head1 EXPORTABLE FUNCTIONS
2038 =head2 is_plain_value
2040 Determines if the supplied argument is a plain value as understood by this
2045 =item * The value is C<undef>
2047 =item * The value is a non-reference
2049 =item * The value is an object with stringification overloading
2051 =item * The value is of the form C<< { -value => $anything } >>
2055 On failure returns C<undef>, on success returns a B<scalar> reference
2056 to the original supplied argument.
2062 The stringification overloading detection is rather advanced: it takes
2063 into consideration not only the presence of a C<""> overload, but if that
2064 fails also checks for enabled
2065 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2066 on either C<0+> or C<bool>.
2068 Unfortunately testing in the field indicates that this
2069 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2070 but only when very large numbers of stringifying objects are involved.
2071 At the time of writing ( Sep 2014 ) there is no clear explanation of
2072 the direct cause, nor is there a manageably small test case that reliably
2073 reproduces the problem.
2075 If you encounter any of the following exceptions in B<random places within
2076 your application stack> - this module may be to blame:
2078 Operation "ne": no method found,
2079 left argument in overloaded package <something>,
2080 right argument in overloaded package <something>
2084 Stub found while resolving method "???" overloading """" in package <something>
2086 If you fall victim to the above - please attempt to reduce the problem
2087 to something that could be sent to the L<SQL::Abstract developers
2088 |DBIx::Class/GETTING HELP/SUPPORT>
2089 (either publicly or privately). As a workaround in the meantime you can
2090 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2091 value, which will most likely eliminate your problem (at the expense of
2092 not being able to properly detect exotic forms of stringification).
2094 This notice and environment variable will be removed in a future version,
2095 as soon as the underlying problem is found and a reliable workaround is
2100 =head2 is_literal_value
2102 Determines if the supplied argument is a literal value as understood by this
2107 =item * C<\$sql_string>
2109 =item * C<\[ $sql_string, @bind_values ]>
2113 On failure returns C<undef>, on success returns an B<array> reference
2114 containing the unpacked version of the supplied literal SQL and bind values.
2116 =head1 WHERE CLAUSES
2120 This module uses a variation on the idea from L<DBIx::Abstract>. It
2121 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2122 module is that things in arrays are OR'ed, and things in hashes
2125 The easiest way to explain is to show lots of examples. After
2126 each C<%where> hash shown, it is assumed you used:
2128 my($stmt, @bind) = $sql->where(\%where);
2130 However, note that the C<%where> hash can be used directly in any
2131 of the other functions as well, as described above.
2133 =head2 Key-value pairs
2135 So, let's get started. To begin, a simple hash:
2139 status => 'completed'
2142 Is converted to SQL C<key = val> statements:
2144 $stmt = "WHERE user = ? AND status = ?";
2145 @bind = ('nwiger', 'completed');
2147 One common thing I end up doing is having a list of values that
2148 a field can be in. To do this, simply specify a list inside of
2153 status => ['assigned', 'in-progress', 'pending'];
2156 This simple code will create the following:
2158 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2159 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2161 A field associated to an empty arrayref will be considered a
2162 logical false and will generate 0=1.
2164 =head2 Tests for NULL values
2166 If the value part is C<undef> then this is converted to SQL <IS NULL>
2175 $stmt = "WHERE user = ? AND status IS NULL";
2178 To test if a column IS NOT NULL:
2182 status => { '!=', undef },
2185 =head2 Specific comparison operators
2187 If you want to specify a different type of operator for your comparison,
2188 you can use a hashref for a given column:
2192 status => { '!=', 'completed' }
2195 Which would generate:
2197 $stmt = "WHERE user = ? AND status != ?";
2198 @bind = ('nwiger', 'completed');
2200 To test against multiple values, just enclose the values in an arrayref:
2202 status => { '=', ['assigned', 'in-progress', 'pending'] };
2204 Which would give you:
2206 "WHERE status = ? OR status = ? OR status = ?"
2209 The hashref can also contain multiple pairs, in which case it is expanded
2210 into an C<AND> of its elements:
2214 status => { '!=', 'completed', -not_like => 'pending%' }
2217 # Or more dynamically, like from a form
2218 $where{user} = 'nwiger';
2219 $where{status}{'!='} = 'completed';
2220 $where{status}{'-not_like'} = 'pending%';
2222 # Both generate this
2223 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2224 @bind = ('nwiger', 'completed', 'pending%');
2227 To get an OR instead, you can combine it with the arrayref idea:
2231 priority => [ { '=', 2 }, { '>', 5 } ]
2234 Which would generate:
2236 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2237 @bind = ('2', '5', 'nwiger');
2239 If you want to include literal SQL (with or without bind values), just use a
2240 scalar reference or reference to an arrayref as the value:
2243 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2244 date_expires => { '<' => \"now()" }
2247 Which would generate:
2249 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2250 @bind = ('11/26/2008');
2253 =head2 Logic and nesting operators
2255 In the example above,
2256 there is a subtle trap if you want to say something like
2257 this (notice the C<AND>):
2259 WHERE priority != ? AND priority != ?
2261 Because, in Perl you I<can't> do this:
2263 priority => { '!=' => 2, '!=' => 1 }
2265 As the second C<!=> key will obliterate the first. The solution
2266 is to use the special C<-modifier> form inside an arrayref:
2268 priority => [ -and => {'!=', 2},
2272 Normally, these would be joined by C<OR>, but the modifier tells it
2273 to use C<AND> instead. (Hint: You can use this in conjunction with the
2274 C<logic> option to C<new()> in order to change the way your queries
2275 work by default.) B<Important:> Note that the C<-modifier> goes
2276 B<INSIDE> the arrayref, as an extra first element. This will
2277 B<NOT> do what you think it might:
2279 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2281 Here is a quick list of equivalencies, since there is some overlap:
2284 status => {'!=', 'completed', 'not like', 'pending%' }
2285 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2288 status => {'=', ['assigned', 'in-progress']}
2289 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2290 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2294 =head2 Special operators: IN, BETWEEN, etc.
2296 You can also use the hashref format to compare a list of fields using the
2297 C<IN> comparison operator, by specifying the list as an arrayref:
2300 status => 'completed',
2301 reportid => { -in => [567, 2335, 2] }
2304 Which would generate:
2306 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2307 @bind = ('completed', '567', '2335', '2');
2309 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2312 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2313 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2314 'sqltrue' (by default: C<1=1>).
2316 In addition to the array you can supply a chunk of literal sql or
2317 literal sql with bind:
2320 customer => { -in => \[
2321 'SELECT cust_id FROM cust WHERE balance > ?',
2324 status => { -in => \'SELECT status_codes FROM states' },
2330 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2331 AND status IN ( SELECT status_codes FROM states )
2335 Finally, if the argument to C<-in> is not a reference, it will be
2336 treated as a single-element array.
2338 Another pair of operators is C<-between> and C<-not_between>,
2339 used with an arrayref of two values:
2343 completion_date => {
2344 -not_between => ['2002-10-01', '2003-02-06']
2350 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2352 Just like with C<-in> all plausible combinations of literal SQL
2356 start0 => { -between => [ 1, 2 ] },
2357 start1 => { -between => \["? AND ?", 1, 2] },
2358 start2 => { -between => \"lower(x) AND upper(y)" },
2359 start3 => { -between => [
2361 \["upper(?)", 'stuff' ],
2368 ( start0 BETWEEN ? AND ? )
2369 AND ( start1 BETWEEN ? AND ? )
2370 AND ( start2 BETWEEN lower(x) AND upper(y) )
2371 AND ( start3 BETWEEN lower(x) AND upper(?) )
2373 @bind = (1, 2, 1, 2, 'stuff');
2376 These are the two builtin "special operators"; but the
2377 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2379 =head2 Unary operators: bool
2381 If you wish to test against boolean columns or functions within your
2382 database you can use the C<-bool> and C<-not_bool> operators. For
2383 example to test the column C<is_user> being true and the column
2384 C<is_enabled> being false you would use:-
2388 -not_bool => 'is_enabled',
2393 WHERE is_user AND NOT is_enabled
2395 If a more complex combination is required, testing more conditions,
2396 then you should use the and/or operators:-
2401 -not_bool => { two=> { -rlike => 'bar' } },
2402 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2413 (NOT ( three = ? OR three > ? ))
2416 =head2 Nested conditions, -and/-or prefixes
2418 So far, we've seen how multiple conditions are joined with a top-level
2419 C<AND>. We can change this by putting the different conditions we want in
2420 hashes and then putting those hashes in an array. For example:
2425 status => { -like => ['pending%', 'dispatched'] },
2429 status => 'unassigned',
2433 This data structure would create the following:
2435 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2436 OR ( user = ? AND status = ? ) )";
2437 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2440 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2441 to change the logic inside:
2447 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2448 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2455 $stmt = "WHERE ( user = ?
2456 AND ( ( workhrs > ? AND geo = ? )
2457 OR ( workhrs < ? OR geo = ? ) ) )";
2458 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2460 =head3 Algebraic inconsistency, for historical reasons
2462 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2463 operator goes C<outside> of the nested structure; whereas when connecting
2464 several constraints on one column, the C<-and> operator goes
2465 C<inside> the arrayref. Here is an example combining both features:
2468 -and => [a => 1, b => 2],
2469 -or => [c => 3, d => 4],
2470 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2475 WHERE ( ( ( a = ? AND b = ? )
2476 OR ( c = ? OR d = ? )
2477 OR ( e LIKE ? AND e LIKE ? ) ) )
2479 This difference in syntax is unfortunate but must be preserved for
2480 historical reasons. So be careful: the two examples below would
2481 seem algebraically equivalent, but they are not
2484 { -like => 'foo%' },
2485 { -like => '%bar' },
2487 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2490 { col => { -like => 'foo%' } },
2491 { col => { -like => '%bar' } },
2493 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2496 =head2 Literal SQL and value type operators
2498 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2499 side" is a column name and the "right side" is a value (normally rendered as
2500 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2501 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2502 alter this behavior. There are several ways of doing so.
2506 This is a virtual operator that signals the string to its right side is an
2507 identifier (a column name) and not a value. For example to compare two
2508 columns you would write:
2511 priority => { '<', 2 },
2512 requestor => { -ident => 'submitter' },
2517 $stmt = "WHERE priority < ? AND requestor = submitter";
2520 If you are maintaining legacy code you may see a different construct as
2521 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2526 This is a virtual operator that signals that the construct to its right side
2527 is a value to be passed to DBI. This is for example necessary when you want
2528 to write a where clause against an array (for RDBMS that support such
2529 datatypes). For example:
2532 array => { -value => [1, 2, 3] }
2537 $stmt = 'WHERE array = ?';
2538 @bind = ([1, 2, 3]);
2540 Note that if you were to simply say:
2546 the result would probably not be what you wanted:
2548 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2553 Finally, sometimes only literal SQL will do. To include a random snippet
2554 of SQL verbatim, you specify it as a scalar reference. Consider this only
2555 as a last resort. Usually there is a better way. For example:
2558 priority => { '<', 2 },
2559 requestor => { -in => \'(SELECT name FROM hitmen)' },
2564 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2567 Note that in this example, you only get one bind parameter back, since
2568 the verbatim SQL is passed as part of the statement.
2572 Never use untrusted input as a literal SQL argument - this is a massive
2573 security risk (there is no way to check literal snippets for SQL
2574 injections and other nastyness). If you need to deal with untrusted input
2575 use literal SQL with placeholders as described next.
2577 =head3 Literal SQL with placeholders and bind values (subqueries)
2579 If the literal SQL to be inserted has placeholders and bind values,
2580 use a reference to an arrayref (yes this is a double reference --
2581 not so common, but perfectly legal Perl). For example, to find a date
2582 in Postgres you can use something like this:
2585 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2590 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2593 Note that you must pass the bind values in the same format as they are returned
2594 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2595 to C<columns>, you must provide the bind values in the
2596 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2597 scalar value; most commonly the column name, but you can use any scalar value
2598 (including references and blessed references), L<SQL::Abstract> will simply
2599 pass it through intact. So if C<bindtype> is set to C<columns> the above
2600 example will look like:
2603 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2606 Literal SQL is especially useful for nesting parenthesized clauses in the
2607 main SQL query. Here is a first example:
2609 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2613 bar => \["IN ($sub_stmt)" => @sub_bind],
2618 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2619 WHERE c2 < ? AND c3 LIKE ?))";
2620 @bind = (1234, 100, "foo%");
2622 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2623 are expressed in the same way. Of course the C<$sub_stmt> and
2624 its associated bind values can be generated through a former call
2627 my ($sub_stmt, @sub_bind)
2628 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2629 c3 => {-like => "foo%"}});
2632 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2635 In the examples above, the subquery was used as an operator on a column;
2636 but the same principle also applies for a clause within the main C<%where>
2637 hash, like an EXISTS subquery:
2639 my ($sub_stmt, @sub_bind)
2640 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2641 my %where = ( -and => [
2643 \["EXISTS ($sub_stmt)" => @sub_bind],
2648 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2649 WHERE c1 = ? AND c2 > t0.c0))";
2653 Observe that the condition on C<c2> in the subquery refers to
2654 column C<t0.c0> of the main query: this is I<not> a bind
2655 value, so we have to express it through a scalar ref.
2656 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2657 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2658 what we wanted here.
2660 Finally, here is an example where a subquery is used
2661 for expressing unary negation:
2663 my ($sub_stmt, @sub_bind)
2664 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2665 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2667 lname => {like => '%son%'},
2668 \["NOT ($sub_stmt)" => @sub_bind],
2673 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2674 @bind = ('%son%', 10, 20)
2676 =head3 Deprecated usage of Literal SQL
2678 Below are some examples of archaic use of literal SQL. It is shown only as
2679 reference for those who deal with legacy code. Each example has a much
2680 better, cleaner and safer alternative that users should opt for in new code.
2686 my %where = ( requestor => \'IS NOT NULL' )
2688 $stmt = "WHERE requestor IS NOT NULL"
2690 This used to be the way of generating NULL comparisons, before the handling
2691 of C<undef> got formalized. For new code please use the superior syntax as
2692 described in L</Tests for NULL values>.
2696 my %where = ( requestor => \'= submitter' )
2698 $stmt = "WHERE requestor = submitter"
2700 This used to be the only way to compare columns. Use the superior L</-ident>
2701 method for all new code. For example an identifier declared in such a way
2702 will be properly quoted if L</quote_char> is properly set, while the legacy
2703 form will remain as supplied.
2707 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2709 $stmt = "WHERE completed > ? AND is_ready"
2710 @bind = ('2012-12-21')
2712 Using an empty string literal used to be the only way to express a boolean.
2713 For all new code please use the much more readable
2714 L<-bool|/Unary operators: bool> operator.
2720 These pages could go on for a while, since the nesting of the data
2721 structures this module can handle are pretty much unlimited (the
2722 module implements the C<WHERE> expansion as a recursive function
2723 internally). Your best bet is to "play around" with the module a
2724 little to see how the data structures behave, and choose the best
2725 format for your data based on that.
2727 And of course, all the values above will probably be replaced with
2728 variables gotten from forms or the command line. After all, if you
2729 knew everything ahead of time, you wouldn't have to worry about
2730 dynamically-generating SQL and could just hardwire it into your
2733 =head1 ORDER BY CLAUSES
2735 Some functions take an order by clause. This can either be a scalar (just a
2736 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2737 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2740 Given | Will Generate
2741 ---------------------------------------------------------------
2743 'colA' | ORDER BY colA
2745 [qw/colA colB/] | ORDER BY colA, colB
2747 {-asc => 'colA'} | ORDER BY colA ASC
2749 {-desc => 'colB'} | ORDER BY colB DESC
2751 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2753 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2755 \'colA DESC' | ORDER BY colA DESC
2757 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2758 | /* ...with $x bound to ? */
2761 { -asc => 'colA' }, | colA ASC,
2762 { -desc => [qw/colB/] }, | colB DESC,
2763 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2764 \'colE DESC', | colE DESC,
2765 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2766 ] | /* ...with $x bound to ? */
2767 ===============================================================
2771 =head1 SPECIAL OPERATORS
2773 my $sqlmaker = SQL::Abstract->new(special_ops => [
2777 my ($self, $field, $op, $arg) = @_;
2783 handler => 'method_name',
2787 A "special operator" is a SQL syntactic clause that can be
2788 applied to a field, instead of a usual binary operator.
2791 WHERE field IN (?, ?, ?)
2792 WHERE field BETWEEN ? AND ?
2793 WHERE MATCH(field) AGAINST (?, ?)
2795 Special operators IN and BETWEEN are fairly standard and therefore
2796 are builtin within C<SQL::Abstract> (as the overridable methods
2797 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2798 like the MATCH .. AGAINST example above which is specific to MySQL,
2799 you can write your own operator handlers - supply a C<special_ops>
2800 argument to the C<new> method. That argument takes an arrayref of
2801 operator definitions; each operator definition is a hashref with two
2808 the regular expression to match the operator
2812 Either a coderef or a plain scalar method name. In both cases
2813 the expected return is C<< ($sql, @bind) >>.
2815 When supplied with a method name, it is simply called on the
2816 L<SQL::Abstract> object as:
2818 $self->$method_name($field, $op, $arg)
2822 $field is the LHS of the operator
2823 $op is the part that matched the handler regex
2826 When supplied with a coderef, it is called as:
2828 $coderef->($self, $field, $op, $arg)
2833 For example, here is an implementation
2834 of the MATCH .. AGAINST syntax for MySQL
2836 my $sqlmaker = SQL::Abstract->new(special_ops => [
2838 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2839 {regex => qr/^match$/i,
2841 my ($self, $field, $op, $arg) = @_;
2842 $arg = [$arg] if not ref $arg;
2843 my $label = $self->_quote($field);
2844 my ($placeholder) = $self->_convert('?');
2845 my $placeholders = join ", ", (($placeholder) x @$arg);
2846 my $sql = $self->_sqlcase('match') . " ($label) "
2847 . $self->_sqlcase('against') . " ($placeholders) ";
2848 my @bind = $self->_bindtype($field, @$arg);
2849 return ($sql, @bind);
2856 =head1 UNARY OPERATORS
2858 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2862 my ($self, $op, $arg) = @_;
2868 handler => 'method_name',
2872 A "unary operator" is a SQL syntactic clause that can be
2873 applied to a field - the operator goes before the field
2875 You can write your own operator handlers - supply a C<unary_ops>
2876 argument to the C<new> method. That argument takes an arrayref of
2877 operator definitions; each operator definition is a hashref with two
2884 the regular expression to match the operator
2888 Either a coderef or a plain scalar method name. In both cases
2889 the expected return is C<< $sql >>.
2891 When supplied with a method name, it is simply called on the
2892 L<SQL::Abstract> object as:
2894 $self->$method_name($op, $arg)
2898 $op is the part that matched the handler regex
2899 $arg is the RHS or argument of the operator
2901 When supplied with a coderef, it is called as:
2903 $coderef->($self, $op, $arg)
2911 Thanks to some benchmarking by Mark Stosberg, it turns out that
2912 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2913 I must admit this wasn't an intentional design issue, but it's a
2914 byproduct of the fact that you get to control your C<DBI> handles
2917 To maximize performance, use a code snippet like the following:
2919 # prepare a statement handle using the first row
2920 # and then reuse it for the rest of the rows
2922 for my $href (@array_of_hashrefs) {
2923 $stmt ||= $sql->insert('table', $href);
2924 $sth ||= $dbh->prepare($stmt);
2925 $sth->execute($sql->values($href));
2928 The reason this works is because the keys in your C<$href> are sorted
2929 internally by B<SQL::Abstract>. Thus, as long as your data retains
2930 the same structure, you only have to generate the SQL the first time
2931 around. On subsequent queries, simply use the C<values> function provided
2932 by this module to return your values in the correct order.
2934 However this depends on the values having the same type - if, for
2935 example, the values of a where clause may either have values
2936 (resulting in sql of the form C<column = ?> with a single bind
2937 value), or alternatively the values might be C<undef> (resulting in
2938 sql of the form C<column IS NULL> with no bind value) then the
2939 caching technique suggested will not work.
2943 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2944 really like this part (I do, at least). Building up a complex query
2945 can be as simple as the following:
2952 use CGI::FormBuilder;
2955 my $form = CGI::FormBuilder->new(...);
2956 my $sql = SQL::Abstract->new;
2958 if ($form->submitted) {
2959 my $field = $form->field;
2960 my $id = delete $field->{id};
2961 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2964 Of course, you would still have to connect using C<DBI> to run the
2965 query, but the point is that if you make your form look like your
2966 table, the actual query script can be extremely simplistic.
2968 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2969 a fast interface to returning and formatting data. I frequently
2970 use these three modules together to write complex database query
2971 apps in under 50 lines.
2973 =head1 HOW TO CONTRIBUTE
2975 Contributions are always welcome, in all usable forms (we especially
2976 welcome documentation improvements). The delivery methods include git-
2977 or unified-diff formatted patches, GitHub pull requests, or plain bug
2978 reports either via RT or the Mailing list. Contributors are generally
2979 granted full access to the official repository after their first several
2980 patches pass successful review.
2982 This project is maintained in a git repository. The code and related tools are
2983 accessible at the following locations:
2987 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2989 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2991 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2993 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2999 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3000 Great care has been taken to preserve the I<published> behavior
3001 documented in previous versions in the 1.* family; however,
3002 some features that were previously undocumented, or behaved
3003 differently from the documentation, had to be changed in order
3004 to clarify the semantics. Hence, client code that was relying
3005 on some dark areas of C<SQL::Abstract> v1.*
3006 B<might behave differently> in v1.50.
3008 The main changes are:
3014 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3018 support for the { operator => \"..." } construct (to embed literal SQL)
3022 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3026 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3030 defensive programming: check arguments
3034 fixed bug with global logic, which was previously implemented
3035 through global variables yielding side-effects. Prior versions would
3036 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3037 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3038 Now this is interpreted
3039 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3044 fixed semantics of _bindtype on array args
3048 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3049 we just avoid shifting arrays within that tree.
3053 dropped the C<_modlogic> function
3057 =head1 ACKNOWLEDGEMENTS
3059 There are a number of individuals that have really helped out with
3060 this module. Unfortunately, most of them submitted bugs via CPAN
3061 so I have no idea who they are! But the people I do know are:
3063 Ash Berlin (order_by hash term support)
3064 Matt Trout (DBIx::Class support)
3065 Mark Stosberg (benchmarking)
3066 Chas Owens (initial "IN" operator support)
3067 Philip Collins (per-field SQL functions)
3068 Eric Kolve (hashref "AND" support)
3069 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3070 Dan Kubb (support for "quote_char" and "name_sep")
3071 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3072 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3073 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3074 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3075 Oliver Charles (support for "RETURNING" after "INSERT")
3081 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3085 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3087 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3089 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3090 While not an official support venue, C<DBIx::Class> makes heavy use of
3091 C<SQL::Abstract>, and as such list members there are very familiar with
3092 how to create queries.
3096 This module is free software; you may copy this under the same
3097 terms as perl itself (either the GNU General Public License or
3098 the Artistic License)