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 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 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
900 # Special case: top level simple string treated as literal
902 my $where_exp = (ref($where)
903 ? $self->_expand_expr($where, $logic)
904 : { -literal => [ $where ] });
905 #::Dwarn([ EXPANDED => $where_exp ]);
907 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
909 # dispatch on appropriate method according to refkind of $where
910 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
912 # my ($sql, @bind) = $self->$method($where_exp, $logic);
914 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
915 # DBIx::Class used to call _recurse_where in scalar context
916 # something else might too...
918 return ($sql, @bind);
921 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
927 my ($self, $ident) = @_;
929 return $self->_convert($self->_quote($ident));
933 my ($self, $value) = @_;
935 return ($self->_convert('?'), $self->_bindtype(undef, $value));
938 my %unop_postfix = map +($_ => 1),
939 'is null', 'is not null',
947 my ($self, $args) = @_;
948 my ($left, $low, $high) = @$args;
949 my ($rhsql, @rhbind) = do {
951 puke "Single arg to between must be a literal"
952 unless $low->{-literal};
955 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
956 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
957 @{$l}[1..$#$l], @{$h}[1..$#$h])
960 my ($lhsql, @lhbind) = $self->_render_expr($left);
962 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
966 }), 'between', 'not between'),
970 my ($self, $args) = @_;
971 my ($lhs, $rhs) = @$args;
974 my ($sql, @bind) = $self->_render_expr($_);
975 push @in_bind, @bind;
978 my ($lhsql, @lbind) = $self->_render_expr($lhs);
980 $lhsql.' '.$self->_sqlcase($op).' ( '
991 my ($op, @args) = @$v;
992 $op =~ s/^-// if length($op) > 1;
994 if (my $h = $special{$op}) {
995 return $self->$h(\@args);
997 my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
998 if ($us and @args > 1) {
999 puke "Special op '${op}' requires first value to be identifier"
1000 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
1001 local our $Expand_Depth = 1;
1002 return $self->${\($us->{handler})}($k, $op, $args[1]);
1004 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
1005 return $self->${\($us->{handler})}($op, $args[0]);
1007 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
1008 if (@args == 1 and $op !~ /^(and|or)$/) {
1009 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
1010 my $op_sql = $self->_sqlcase($final_op);
1012 $unop_postfix{lc($final_op)}
1013 ? "${expr_sql} ${op_sql}"
1014 : "${op_sql} ${expr_sql}"
1016 return (($op eq 'not' || $us ? '('.$final_sql.')' : $final_sql), @bind);
1017 #} elsif (@args == 0) {
1020 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @args;
1021 return '' unless @parts;
1022 my $is_andor = !!($op =~ /^(and|or)$/);
1023 return @{$parts[0]} if $is_andor and @parts == 1;
1024 my ($final_sql) = map +($is_andor ? "( ${_} )" : $_), join(
1025 ' '.$self->_sqlcase($final_op).' ',
1030 map @{$_}[1..$#$_], @parts
1037 my ($self, $list) = @_;
1038 my @parts = grep length($_->[0]), map [ $self->_render_expr($_) ], @$list;
1039 return join(', ', map $_->[0], @parts), map @{$_}[1..$#$_], @parts;
1043 my ($self, $rest) = @_;
1044 my ($func, @args) = @$rest;
1048 push @arg_sql, shift @x;
1050 } map [ $self->_render_expr($_) ], @args;
1051 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1055 my ($self, $bind) = @_;
1056 return ($self->_convert('?'), $self->_bindtype(@$bind));
1059 sub _render_literal {
1060 my ($self, $literal) = @_;
1061 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1065 # Some databases (SQLite) treat col IN (1, 2) different from
1066 # col IN ( (1, 2) ). Use this to strip all outer parens while
1067 # adding them back in the corresponding method
1068 sub _open_outer_paren {
1069 my ($self, $sql) = @_;
1071 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1073 # there are closing parens inside, need the heavy duty machinery
1074 # to reevaluate the extraction starting from $sql (full reevaluation)
1075 if ($inner =~ /\)/) {
1076 require Text::Balanced;
1078 my (undef, $remainder) = do {
1079 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1081 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1084 # the entire expression needs to be a balanced bracketed thing
1085 # (after an extract no remainder sans trailing space)
1086 last if defined $remainder and $remainder =~ /\S/;
1096 #======================================================================
1098 #======================================================================
1100 sub _expand_order_by {
1101 my ($self, $arg) = @_;
1103 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1105 my $expander = sub {
1106 my ($self, $dir, $expr) = @_;
1107 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1108 foreach my $arg (@to_expand) {
1112 and grep /^-(asc|desc)$/, keys %$arg
1114 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1117 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1118 map $self->_expand_expr($_, undef, -ident),
1119 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1120 return (@exp > 1 ? { -list => \@exp } : $exp[0]);
1123 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1124 sub { shift->$expander(asc => @_) },
1125 sub { shift->$expander(desc => @_) },
1128 return $self->$expander(undef, $arg);
1132 my ($self, $arg) = @_;
1134 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1136 my ($sql, @bind) = $self->_render_expr($expanded);
1138 return '' unless length($sql);
1140 my $final_sql = $self->_sqlcase(' order by ').$sql;
1142 return wantarray ? ($final_sql, @bind) : $final_sql;
1145 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1147 sub _order_by_chunks {
1148 my ($self, $arg) = @_;
1150 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1152 return $self->_chunkify_order_by($expanded);
1155 sub _chunkify_order_by {
1156 my ($self, $expanded) = @_;
1158 return grep length, $self->_render_expr($expanded)
1159 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1162 if (ref() eq 'HASH' and my $l = $_->{-list}) {
1163 return map $self->_chunkify_order_by($_), @$l;
1165 return [ $self->_render_expr($_) ];
1169 #======================================================================
1170 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1171 #======================================================================
1176 ($self->_render_expr(
1177 $self->_expand_maybe_list_expr($from, undef, -ident)
1182 #======================================================================
1184 #======================================================================
1186 sub _expand_maybe_list_expr {
1187 my ($self, $expr, $logic, $default) = @_;
1189 if (ref($expr) eq 'ARRAY') {
1191 map $self->_expand_expr($_, $logic, $default), @$expr
1198 return $self->_expand_expr($e, $logic, $default);
1201 # highly optimized, as it's called way too often
1203 # my ($self, $label) = @_;
1205 return '' unless defined $_[1];
1206 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1207 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1209 unless ($_[0]->{quote_char}) {
1210 if (ref($_[1]) eq 'ARRAY') {
1211 return join($_[0]->{name_sep}||'.', @{$_[1]});
1213 $_[0]->_assert_pass_injection_guard($_[1]);
1218 my $qref = ref $_[0]->{quote_char};
1220 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1221 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1222 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1224 my $esc = $_[0]->{escape_char} || $r;
1226 # parts containing * are naturally unquoted
1228 $_[0]->{name_sep}||'',
1232 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1234 (ref($_[1]) eq 'ARRAY'
1238 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1246 # Conversion, if applicable
1248 #my ($self, $arg) = @_;
1249 if ($_[0]->{convert_where}) {
1250 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1257 #my ($self, $col, @vals) = @_;
1258 # called often - tighten code
1259 return $_[0]->{bindtype} eq 'columns'
1260 ? map {[$_[1], $_]} @_[2 .. $#_]
1265 # Dies if any element of @bind is not in [colname => value] format
1266 # if bindtype is 'columns'.
1267 sub _assert_bindval_matches_bindtype {
1268 # my ($self, @bind) = @_;
1270 if ($self->{bindtype} eq 'columns') {
1272 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1273 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1279 sub _join_sql_clauses {
1280 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1282 if (@$clauses_aref > 1) {
1283 my $join = " " . $self->_sqlcase($logic) . " ";
1284 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1285 return ($sql, @$bind_aref);
1287 elsif (@$clauses_aref) {
1288 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1291 return (); # if no SQL, ignore @$bind_aref
1296 # Fix SQL case, if so requested
1298 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1299 # don't touch the argument ... crooked logic, but let's not change it!
1300 return $_[0]->{case} ? $_[1] : uc($_[1]);
1304 #======================================================================
1305 # DISPATCHING FROM REFKIND
1306 #======================================================================
1309 my ($self, $data) = @_;
1311 return 'UNDEF' unless defined $data;
1313 # blessed objects are treated like scalars
1314 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1316 return 'SCALAR' unless $ref;
1319 while ($ref eq 'REF') {
1321 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1325 return ($ref||'SCALAR') . ('REF' x $n_steps);
1329 my ($self, $data) = @_;
1330 my @try = ($self->_refkind($data));
1331 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1332 push @try, 'FALLBACK';
1336 sub _METHOD_FOR_refkind {
1337 my ($self, $meth_prefix, $data) = @_;
1340 for (@{$self->_try_refkind($data)}) {
1341 $method = $self->can($meth_prefix."_".$_)
1345 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1349 sub _SWITCH_refkind {
1350 my ($self, $data, $dispatch_table) = @_;
1353 for (@{$self->_try_refkind($data)}) {
1354 $coderef = $dispatch_table->{$_}
1358 puke "no dispatch entry for ".$self->_refkind($data)
1367 #======================================================================
1368 # VALUES, GENERATE, AUTOLOAD
1369 #======================================================================
1371 # LDNOTE: original code from nwiger, didn't touch code in that section
1372 # I feel the AUTOLOAD stuff should not be the default, it should
1373 # only be activated on explicit demand by user.
1377 my $data = shift || return;
1378 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1379 unless ref $data eq 'HASH';
1382 foreach my $k (sort keys %$data) {
1383 my $v = $data->{$k};
1384 $self->_SWITCH_refkind($v, {
1386 if ($self->{array_datatypes}) { # array datatype
1387 push @all_bind, $self->_bindtype($k, $v);
1389 else { # literal SQL with bind
1390 my ($sql, @bind) = @$v;
1391 $self->_assert_bindval_matches_bindtype(@bind);
1392 push @all_bind, @bind;
1395 ARRAYREFREF => sub { # literal SQL with bind
1396 my ($sql, @bind) = @${$v};
1397 $self->_assert_bindval_matches_bindtype(@bind);
1398 push @all_bind, @bind;
1400 SCALARREF => sub { # literal SQL without bind
1402 SCALAR_or_UNDEF => sub {
1403 push @all_bind, $self->_bindtype($k, $v);
1414 my(@sql, @sqlq, @sqlv);
1418 if ($ref eq 'HASH') {
1419 for my $k (sort keys %$_) {
1422 my $label = $self->_quote($k);
1423 if ($r eq 'ARRAY') {
1424 # literal SQL with bind
1425 my ($sql, @bind) = @$v;
1426 $self->_assert_bindval_matches_bindtype(@bind);
1427 push @sqlq, "$label = $sql";
1429 } elsif ($r eq 'SCALAR') {
1430 # literal SQL without bind
1431 push @sqlq, "$label = $$v";
1433 push @sqlq, "$label = ?";
1434 push @sqlv, $self->_bindtype($k, $v);
1437 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1438 } elsif ($ref eq 'ARRAY') {
1439 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1442 if ($r eq 'ARRAY') { # literal SQL with bind
1443 my ($sql, @bind) = @$v;
1444 $self->_assert_bindval_matches_bindtype(@bind);
1447 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1448 # embedded literal SQL
1455 push @sql, '(' . join(', ', @sqlq) . ')';
1456 } elsif ($ref eq 'SCALAR') {
1460 # strings get case twiddled
1461 push @sql, $self->_sqlcase($_);
1465 my $sql = join ' ', @sql;
1467 # this is pretty tricky
1468 # if ask for an array, return ($stmt, @bind)
1469 # otherwise, s/?/shift @sqlv/ to put it inline
1471 return ($sql, @sqlv);
1473 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1474 ref $d ? $d->[1] : $d/e;
1483 # This allows us to check for a local, then _form, attr
1485 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1486 return $self->generate($name, @_);
1497 SQL::Abstract - Generate SQL from Perl data structures
1503 my $sql = SQL::Abstract->new;
1505 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1507 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1509 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1511 my($stmt, @bind) = $sql->delete($table, \%where);
1513 # Then, use these in your DBI statements
1514 my $sth = $dbh->prepare($stmt);
1515 $sth->execute(@bind);
1517 # Just generate the WHERE clause
1518 my($stmt, @bind) = $sql->where(\%where, $order);
1520 # Return values in the same order, for hashed queries
1521 # See PERFORMANCE section for more details
1522 my @bind = $sql->values(\%fieldvals);
1526 This module was inspired by the excellent L<DBIx::Abstract>.
1527 However, in using that module I found that what I really wanted
1528 to do was generate SQL, but still retain complete control over my
1529 statement handles and use the DBI interface. So, I set out to
1530 create an abstract SQL generation module.
1532 While based on the concepts used by L<DBIx::Abstract>, there are
1533 several important differences, especially when it comes to WHERE
1534 clauses. I have modified the concepts used to make the SQL easier
1535 to generate from Perl data structures and, IMO, more intuitive.
1536 The underlying idea is for this module to do what you mean, based
1537 on the data structures you provide it. The big advantage is that
1538 you don't have to modify your code every time your data changes,
1539 as this module figures it out.
1541 To begin with, an SQL INSERT is as easy as just specifying a hash
1542 of C<key=value> pairs:
1545 name => 'Jimbo Bobson',
1546 phone => '123-456-7890',
1547 address => '42 Sister Lane',
1548 city => 'St. Louis',
1549 state => 'Louisiana',
1552 The SQL can then be generated with this:
1554 my($stmt, @bind) = $sql->insert('people', \%data);
1556 Which would give you something like this:
1558 $stmt = "INSERT INTO people
1559 (address, city, name, phone, state)
1560 VALUES (?, ?, ?, ?, ?)";
1561 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1562 '123-456-7890', 'Louisiana');
1564 These are then used directly in your DBI code:
1566 my $sth = $dbh->prepare($stmt);
1567 $sth->execute(@bind);
1569 =head2 Inserting and Updating Arrays
1571 If your database has array types (like for example Postgres),
1572 activate the special option C<< array_datatypes => 1 >>
1573 when creating the C<SQL::Abstract> object.
1574 Then you may use an arrayref to insert and update database array types:
1576 my $sql = SQL::Abstract->new(array_datatypes => 1);
1578 planets => [qw/Mercury Venus Earth Mars/]
1581 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1585 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1587 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1590 =head2 Inserting and Updating SQL
1592 In order to apply SQL functions to elements of your C<%data> you may
1593 specify a reference to an arrayref for the given hash value. For example,
1594 if you need to execute the Oracle C<to_date> function on a value, you can
1595 say something like this:
1599 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1602 The first value in the array is the actual SQL. Any other values are
1603 optional and would be included in the bind values array. This gives
1606 my($stmt, @bind) = $sql->insert('people', \%data);
1608 $stmt = "INSERT INTO people (name, date_entered)
1609 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1610 @bind = ('Bill', '03/02/2003');
1612 An UPDATE is just as easy, all you change is the name of the function:
1614 my($stmt, @bind) = $sql->update('people', \%data);
1616 Notice that your C<%data> isn't touched; the module will generate
1617 the appropriately quirky SQL for you automatically. Usually you'll
1618 want to specify a WHERE clause for your UPDATE, though, which is
1619 where handling C<%where> hashes comes in handy...
1621 =head2 Complex where statements
1623 This module can generate pretty complicated WHERE statements
1624 easily. For example, simple C<key=value> pairs are taken to mean
1625 equality, and if you want to see if a field is within a set
1626 of values, you can use an arrayref. Let's say we wanted to
1627 SELECT some data based on this criteria:
1630 requestor => 'inna',
1631 worker => ['nwiger', 'rcwe', 'sfz'],
1632 status => { '!=', 'completed' }
1635 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1637 The above would give you something like this:
1639 $stmt = "SELECT * FROM tickets WHERE
1640 ( requestor = ? ) AND ( status != ? )
1641 AND ( worker = ? OR worker = ? OR worker = ? )";
1642 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1644 Which you could then use in DBI code like so:
1646 my $sth = $dbh->prepare($stmt);
1647 $sth->execute(@bind);
1653 The methods are simple. There's one for every major SQL operation,
1654 and a constructor you use first. The arguments are specified in a
1655 similar order for each method (table, then fields, then a where
1656 clause) to try and simplify things.
1658 =head2 new(option => 'value')
1660 The C<new()> function takes a list of options and values, and returns
1661 a new B<SQL::Abstract> object which can then be used to generate SQL
1662 through the methods below. The options accepted are:
1668 If set to 'lower', then SQL will be generated in all lowercase. By
1669 default SQL is generated in "textbook" case meaning something like:
1671 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1673 Any setting other than 'lower' is ignored.
1677 This determines what the default comparison operator is. By default
1678 it is C<=>, meaning that a hash like this:
1680 %where = (name => 'nwiger', email => 'nate@wiger.org');
1682 Will generate SQL like this:
1684 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1686 However, you may want loose comparisons by default, so if you set
1687 C<cmp> to C<like> you would get SQL such as:
1689 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1691 You can also override the comparison on an individual basis - see
1692 the huge section on L</"WHERE CLAUSES"> at the bottom.
1694 =item sqltrue, sqlfalse
1696 Expressions for inserting boolean values within SQL statements.
1697 By default these are C<1=1> and C<1=0>. They are used
1698 by the special operators C<-in> and C<-not_in> for generating
1699 correct SQL even when the argument is an empty array (see below).
1703 This determines the default logical operator for multiple WHERE
1704 statements in arrays or hashes. If absent, the default logic is "or"
1705 for arrays, and "and" for hashes. This means that a WHERE
1709 event_date => {'>=', '2/13/99'},
1710 event_date => {'<=', '4/24/03'},
1713 will generate SQL like this:
1715 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1717 This is probably not what you want given this query, though (look
1718 at the dates). To change the "OR" to an "AND", simply specify:
1720 my $sql = SQL::Abstract->new(logic => 'and');
1722 Which will change the above C<WHERE> to:
1724 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1726 The logic can also be changed locally by inserting
1727 a modifier in front of an arrayref:
1729 @where = (-and => [event_date => {'>=', '2/13/99'},
1730 event_date => {'<=', '4/24/03'} ]);
1732 See the L</"WHERE CLAUSES"> section for explanations.
1736 This will automatically convert comparisons using the specified SQL
1737 function for both column and value. This is mostly used with an argument
1738 of C<upper> or C<lower>, so that the SQL will have the effect of
1739 case-insensitive "searches". For example, this:
1741 $sql = SQL::Abstract->new(convert => 'upper');
1742 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1744 Will turn out the following SQL:
1746 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1748 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1749 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1750 not validate this option; it will just pass through what you specify verbatim).
1754 This is a kludge because many databases suck. For example, you can't
1755 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1756 Instead, you have to use C<bind_param()>:
1758 $sth->bind_param(1, 'reg data');
1759 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1761 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1762 which loses track of which field each slot refers to. Fear not.
1764 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1765 Currently, you can specify either C<normal> (default) or C<columns>. If you
1766 specify C<columns>, you will get an array that looks like this:
1768 my $sql = SQL::Abstract->new(bindtype => 'columns');
1769 my($stmt, @bind) = $sql->insert(...);
1772 [ 'column1', 'value1' ],
1773 [ 'column2', 'value2' ],
1774 [ 'column3', 'value3' ],
1777 You can then iterate through this manually, using DBI's C<bind_param()>.
1779 $sth->prepare($stmt);
1782 my($col, $data) = @$_;
1783 if ($col eq 'details' || $col eq 'comments') {
1784 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1785 } elsif ($col eq 'image') {
1786 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1788 $sth->bind_param($i, $data);
1792 $sth->execute; # execute without @bind now
1794 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1795 Basically, the advantage is still that you don't have to care which fields
1796 are or are not included. You could wrap that above C<for> loop in a simple
1797 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1798 get a layer of abstraction over manual SQL specification.
1800 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1801 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1802 will expect the bind values in this format.
1806 This is the character that a table or column name will be quoted
1807 with. By default this is an empty string, but you could set it to
1808 the character C<`>, to generate SQL like this:
1810 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1812 Alternatively, you can supply an array ref of two items, the first being the left
1813 hand quote character, and the second the right hand quote character. For
1814 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1815 that generates SQL like this:
1817 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1819 Quoting is useful if you have tables or columns names that are reserved
1820 words in your database's SQL dialect.
1824 This is the character that will be used to escape L</quote_char>s appearing
1825 in an identifier before it has been quoted.
1827 The parameter default in case of a single L</quote_char> character is the quote
1830 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1831 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1832 of the B<opening (left)> L</quote_char> within the identifier are currently left
1833 untouched. The default for opening-closing-style quotes may change in future
1834 versions, thus you are B<strongly encouraged> to specify the escape character
1839 This is the character that separates a table and column name. It is
1840 necessary to specify this when the C<quote_char> option is selected,
1841 so that tables and column names can be individually quoted like this:
1843 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1845 =item injection_guard
1847 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1848 column name specified in a query structure. This is a safety mechanism to avoid
1849 injection attacks when mishandling user input e.g.:
1851 my %condition_as_column_value_pairs = get_values_from_user();
1852 $sqla->select( ... , \%condition_as_column_value_pairs );
1854 If the expression matches an exception is thrown. Note that literal SQL
1855 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1857 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1859 =item array_datatypes
1861 When this option is true, arrayrefs in INSERT or UPDATE are
1862 interpreted as array datatypes and are passed directly
1864 When this option is false, arrayrefs are interpreted
1865 as literal SQL, just like refs to arrayrefs
1866 (but this behavior is for backwards compatibility; when writing
1867 new queries, use the "reference to arrayref" syntax
1873 Takes a reference to a list of "special operators"
1874 to extend the syntax understood by L<SQL::Abstract>.
1875 See section L</"SPECIAL OPERATORS"> for details.
1879 Takes a reference to a list of "unary operators"
1880 to extend the syntax understood by L<SQL::Abstract>.
1881 See section L</"UNARY OPERATORS"> for details.
1887 =head2 insert($table, \@values || \%fieldvals, \%options)
1889 This is the simplest function. You simply give it a table name
1890 and either an arrayref of values or hashref of field/value pairs.
1891 It returns an SQL INSERT statement and a list of bind values.
1892 See the sections on L</"Inserting and Updating Arrays"> and
1893 L</"Inserting and Updating SQL"> for information on how to insert
1894 with those data types.
1896 The optional C<\%options> hash reference may contain additional
1897 options to generate the insert SQL. Currently supported options
1904 Takes either a scalar of raw SQL fields, or an array reference of
1905 field names, and adds on an SQL C<RETURNING> statement at the end.
1906 This allows you to return data generated by the insert statement
1907 (such as row IDs) without performing another C<SELECT> statement.
1908 Note, however, this is not part of the SQL standard and may not
1909 be supported by all database engines.
1913 =head2 update($table, \%fieldvals, \%where, \%options)
1915 This takes a table, hashref of field/value pairs, and an optional
1916 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1918 See the sections on L</"Inserting and Updating Arrays"> and
1919 L</"Inserting and Updating SQL"> for information on how to insert
1920 with those data types.
1922 The optional C<\%options> hash reference may contain additional
1923 options to generate the update SQL. Currently supported options
1930 See the C<returning> option to
1931 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1935 =head2 select($source, $fields, $where, $order)
1937 This returns a SQL SELECT statement and associated list of bind values, as
1938 specified by the arguments:
1944 Specification of the 'FROM' part of the statement.
1945 The argument can be either a plain scalar (interpreted as a table
1946 name, will be quoted), or an arrayref (interpreted as a list
1947 of table names, joined by commas, quoted), or a scalarref
1948 (literal SQL, not quoted).
1952 Specification of the list of fields to retrieve from
1954 The argument can be either an arrayref (interpreted as a list
1955 of field names, will be joined by commas and quoted), or a
1956 plain scalar (literal SQL, not quoted).
1957 Please observe that this API is not as flexible as that of
1958 the first argument C<$source>, for backwards compatibility reasons.
1962 Optional argument to specify the WHERE part of the query.
1963 The argument is most often a hashref, but can also be
1964 an arrayref or plain scalar --
1965 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1969 Optional argument to specify the ORDER BY part of the query.
1970 The argument can be a scalar, a hashref or an arrayref
1971 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1977 =head2 delete($table, \%where, \%options)
1979 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1980 It returns an SQL DELETE statement and list of bind values.
1982 The optional C<\%options> hash reference may contain additional
1983 options to generate the delete SQL. Currently supported options
1990 See the C<returning> option to
1991 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1995 =head2 where(\%where, $order)
1997 This is used to generate just the WHERE clause. For example,
1998 if you have an arbitrary data structure and know what the
1999 rest of your SQL is going to look like, but want an easy way
2000 to produce a WHERE clause, use this. It returns an SQL WHERE
2001 clause and list of bind values.
2004 =head2 values(\%data)
2006 This just returns the values from the hash C<%data>, in the same
2007 order that would be returned from any of the other above queries.
2008 Using this allows you to markedly speed up your queries if you
2009 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2011 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2013 Warning: This is an experimental method and subject to change.
2015 This returns arbitrarily generated SQL. It's a really basic shortcut.
2016 It will return two different things, depending on return context:
2018 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2019 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2021 These would return the following:
2023 # First calling form
2024 $stmt = "CREATE TABLE test (?, ?)";
2025 @bind = (field1, field2);
2027 # Second calling form
2028 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2030 Depending on what you're trying to do, it's up to you to choose the correct
2031 format. In this example, the second form is what you would want.
2035 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2039 ALTER SESSION SET nls_date_format = 'MM/YY'
2041 You get the idea. Strings get their case twiddled, but everything
2042 else remains verbatim.
2044 =head1 EXPORTABLE FUNCTIONS
2046 =head2 is_plain_value
2048 Determines if the supplied argument is a plain value as understood by this
2053 =item * The value is C<undef>
2055 =item * The value is a non-reference
2057 =item * The value is an object with stringification overloading
2059 =item * The value is of the form C<< { -value => $anything } >>
2063 On failure returns C<undef>, on success returns a B<scalar> reference
2064 to the original supplied argument.
2070 The stringification overloading detection is rather advanced: it takes
2071 into consideration not only the presence of a C<""> overload, but if that
2072 fails also checks for enabled
2073 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2074 on either C<0+> or C<bool>.
2076 Unfortunately testing in the field indicates that this
2077 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2078 but only when very large numbers of stringifying objects are involved.
2079 At the time of writing ( Sep 2014 ) there is no clear explanation of
2080 the direct cause, nor is there a manageably small test case that reliably
2081 reproduces the problem.
2083 If you encounter any of the following exceptions in B<random places within
2084 your application stack> - this module may be to blame:
2086 Operation "ne": no method found,
2087 left argument in overloaded package <something>,
2088 right argument in overloaded package <something>
2092 Stub found while resolving method "???" overloading """" in package <something>
2094 If you fall victim to the above - please attempt to reduce the problem
2095 to something that could be sent to the L<SQL::Abstract developers
2096 |DBIx::Class/GETTING HELP/SUPPORT>
2097 (either publicly or privately). As a workaround in the meantime you can
2098 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2099 value, which will most likely eliminate your problem (at the expense of
2100 not being able to properly detect exotic forms of stringification).
2102 This notice and environment variable will be removed in a future version,
2103 as soon as the underlying problem is found and a reliable workaround is
2108 =head2 is_literal_value
2110 Determines if the supplied argument is a literal value as understood by this
2115 =item * C<\$sql_string>
2117 =item * C<\[ $sql_string, @bind_values ]>
2121 On failure returns C<undef>, on success returns an B<array> reference
2122 containing the unpacked version of the supplied literal SQL and bind values.
2124 =head1 WHERE CLAUSES
2128 This module uses a variation on the idea from L<DBIx::Abstract>. It
2129 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2130 module is that things in arrays are OR'ed, and things in hashes
2133 The easiest way to explain is to show lots of examples. After
2134 each C<%where> hash shown, it is assumed you used:
2136 my($stmt, @bind) = $sql->where(\%where);
2138 However, note that the C<%where> hash can be used directly in any
2139 of the other functions as well, as described above.
2141 =head2 Key-value pairs
2143 So, let's get started. To begin, a simple hash:
2147 status => 'completed'
2150 Is converted to SQL C<key = val> statements:
2152 $stmt = "WHERE user = ? AND status = ?";
2153 @bind = ('nwiger', 'completed');
2155 One common thing I end up doing is having a list of values that
2156 a field can be in. To do this, simply specify a list inside of
2161 status => ['assigned', 'in-progress', 'pending'];
2164 This simple code will create the following:
2166 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2167 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2169 A field associated to an empty arrayref will be considered a
2170 logical false and will generate 0=1.
2172 =head2 Tests for NULL values
2174 If the value part is C<undef> then this is converted to SQL <IS NULL>
2183 $stmt = "WHERE user = ? AND status IS NULL";
2186 To test if a column IS NOT NULL:
2190 status => { '!=', undef },
2193 =head2 Specific comparison operators
2195 If you want to specify a different type of operator for your comparison,
2196 you can use a hashref for a given column:
2200 status => { '!=', 'completed' }
2203 Which would generate:
2205 $stmt = "WHERE user = ? AND status != ?";
2206 @bind = ('nwiger', 'completed');
2208 To test against multiple values, just enclose the values in an arrayref:
2210 status => { '=', ['assigned', 'in-progress', 'pending'] };
2212 Which would give you:
2214 "WHERE status = ? OR status = ? OR status = ?"
2217 The hashref can also contain multiple pairs, in which case it is expanded
2218 into an C<AND> of its elements:
2222 status => { '!=', 'completed', -not_like => 'pending%' }
2225 # Or more dynamically, like from a form
2226 $where{user} = 'nwiger';
2227 $where{status}{'!='} = 'completed';
2228 $where{status}{'-not_like'} = 'pending%';
2230 # Both generate this
2231 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2232 @bind = ('nwiger', 'completed', 'pending%');
2235 To get an OR instead, you can combine it with the arrayref idea:
2239 priority => [ { '=', 2 }, { '>', 5 } ]
2242 Which would generate:
2244 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2245 @bind = ('2', '5', 'nwiger');
2247 If you want to include literal SQL (with or without bind values), just use a
2248 scalar reference or reference to an arrayref as the value:
2251 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2252 date_expires => { '<' => \"now()" }
2255 Which would generate:
2257 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2258 @bind = ('11/26/2008');
2261 =head2 Logic and nesting operators
2263 In the example above,
2264 there is a subtle trap if you want to say something like
2265 this (notice the C<AND>):
2267 WHERE priority != ? AND priority != ?
2269 Because, in Perl you I<can't> do this:
2271 priority => { '!=' => 2, '!=' => 1 }
2273 As the second C<!=> key will obliterate the first. The solution
2274 is to use the special C<-modifier> form inside an arrayref:
2276 priority => [ -and => {'!=', 2},
2280 Normally, these would be joined by C<OR>, but the modifier tells it
2281 to use C<AND> instead. (Hint: You can use this in conjunction with the
2282 C<logic> option to C<new()> in order to change the way your queries
2283 work by default.) B<Important:> Note that the C<-modifier> goes
2284 B<INSIDE> the arrayref, as an extra first element. This will
2285 B<NOT> do what you think it might:
2287 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2289 Here is a quick list of equivalencies, since there is some overlap:
2292 status => {'!=', 'completed', 'not like', 'pending%' }
2293 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2296 status => {'=', ['assigned', 'in-progress']}
2297 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2298 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2302 =head2 Special operators: IN, BETWEEN, etc.
2304 You can also use the hashref format to compare a list of fields using the
2305 C<IN> comparison operator, by specifying the list as an arrayref:
2308 status => 'completed',
2309 reportid => { -in => [567, 2335, 2] }
2312 Which would generate:
2314 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2315 @bind = ('completed', '567', '2335', '2');
2317 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2320 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2321 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2322 'sqltrue' (by default: C<1=1>).
2324 In addition to the array you can supply a chunk of literal sql or
2325 literal sql with bind:
2328 customer => { -in => \[
2329 'SELECT cust_id FROM cust WHERE balance > ?',
2332 status => { -in => \'SELECT status_codes FROM states' },
2338 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2339 AND status IN ( SELECT status_codes FROM states )
2343 Finally, if the argument to C<-in> is not a reference, it will be
2344 treated as a single-element array.
2346 Another pair of operators is C<-between> and C<-not_between>,
2347 used with an arrayref of two values:
2351 completion_date => {
2352 -not_between => ['2002-10-01', '2003-02-06']
2358 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2360 Just like with C<-in> all plausible combinations of literal SQL
2364 start0 => { -between => [ 1, 2 ] },
2365 start1 => { -between => \["? AND ?", 1, 2] },
2366 start2 => { -between => \"lower(x) AND upper(y)" },
2367 start3 => { -between => [
2369 \["upper(?)", 'stuff' ],
2376 ( start0 BETWEEN ? AND ? )
2377 AND ( start1 BETWEEN ? AND ? )
2378 AND ( start2 BETWEEN lower(x) AND upper(y) )
2379 AND ( start3 BETWEEN lower(x) AND upper(?) )
2381 @bind = (1, 2, 1, 2, 'stuff');
2384 These are the two builtin "special operators"; but the
2385 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2387 =head2 Unary operators: bool
2389 If you wish to test against boolean columns or functions within your
2390 database you can use the C<-bool> and C<-not_bool> operators. For
2391 example to test the column C<is_user> being true and the column
2392 C<is_enabled> being false you would use:-
2396 -not_bool => 'is_enabled',
2401 WHERE is_user AND NOT is_enabled
2403 If a more complex combination is required, testing more conditions,
2404 then you should use the and/or operators:-
2409 -not_bool => { two=> { -rlike => 'bar' } },
2410 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2421 (NOT ( three = ? OR three > ? ))
2424 =head2 Nested conditions, -and/-or prefixes
2426 So far, we've seen how multiple conditions are joined with a top-level
2427 C<AND>. We can change this by putting the different conditions we want in
2428 hashes and then putting those hashes in an array. For example:
2433 status => { -like => ['pending%', 'dispatched'] },
2437 status => 'unassigned',
2441 This data structure would create the following:
2443 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2444 OR ( user = ? AND status = ? ) )";
2445 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2448 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2449 to change the logic inside:
2455 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2456 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2463 $stmt = "WHERE ( user = ?
2464 AND ( ( workhrs > ? AND geo = ? )
2465 OR ( workhrs < ? OR geo = ? ) ) )";
2466 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2468 =head3 Algebraic inconsistency, for historical reasons
2470 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2471 operator goes C<outside> of the nested structure; whereas when connecting
2472 several constraints on one column, the C<-and> operator goes
2473 C<inside> the arrayref. Here is an example combining both features:
2476 -and => [a => 1, b => 2],
2477 -or => [c => 3, d => 4],
2478 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2483 WHERE ( ( ( a = ? AND b = ? )
2484 OR ( c = ? OR d = ? )
2485 OR ( e LIKE ? AND e LIKE ? ) ) )
2487 This difference in syntax is unfortunate but must be preserved for
2488 historical reasons. So be careful: the two examples below would
2489 seem algebraically equivalent, but they are not
2492 { -like => 'foo%' },
2493 { -like => '%bar' },
2495 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2498 { col => { -like => 'foo%' } },
2499 { col => { -like => '%bar' } },
2501 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2504 =head2 Literal SQL and value type operators
2506 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2507 side" is a column name and the "right side" is a value (normally rendered as
2508 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2509 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2510 alter this behavior. There are several ways of doing so.
2514 This is a virtual operator that signals the string to its right side is an
2515 identifier (a column name) and not a value. For example to compare two
2516 columns you would write:
2519 priority => { '<', 2 },
2520 requestor => { -ident => 'submitter' },
2525 $stmt = "WHERE priority < ? AND requestor = submitter";
2528 If you are maintaining legacy code you may see a different construct as
2529 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2534 This is a virtual operator that signals that the construct to its right side
2535 is a value to be passed to DBI. This is for example necessary when you want
2536 to write a where clause against an array (for RDBMS that support such
2537 datatypes). For example:
2540 array => { -value => [1, 2, 3] }
2545 $stmt = 'WHERE array = ?';
2546 @bind = ([1, 2, 3]);
2548 Note that if you were to simply say:
2554 the result would probably not be what you wanted:
2556 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2561 Finally, sometimes only literal SQL will do. To include a random snippet
2562 of SQL verbatim, you specify it as a scalar reference. Consider this only
2563 as a last resort. Usually there is a better way. For example:
2566 priority => { '<', 2 },
2567 requestor => { -in => \'(SELECT name FROM hitmen)' },
2572 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2575 Note that in this example, you only get one bind parameter back, since
2576 the verbatim SQL is passed as part of the statement.
2580 Never use untrusted input as a literal SQL argument - this is a massive
2581 security risk (there is no way to check literal snippets for SQL
2582 injections and other nastyness). If you need to deal with untrusted input
2583 use literal SQL with placeholders as described next.
2585 =head3 Literal SQL with placeholders and bind values (subqueries)
2587 If the literal SQL to be inserted has placeholders and bind values,
2588 use a reference to an arrayref (yes this is a double reference --
2589 not so common, but perfectly legal Perl). For example, to find a date
2590 in Postgres you can use something like this:
2593 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2598 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2601 Note that you must pass the bind values in the same format as they are returned
2602 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2603 to C<columns>, you must provide the bind values in the
2604 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2605 scalar value; most commonly the column name, but you can use any scalar value
2606 (including references and blessed references), L<SQL::Abstract> will simply
2607 pass it through intact. So if C<bindtype> is set to C<columns> the above
2608 example will look like:
2611 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2614 Literal SQL is especially useful for nesting parenthesized clauses in the
2615 main SQL query. Here is a first example:
2617 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2621 bar => \["IN ($sub_stmt)" => @sub_bind],
2626 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2627 WHERE c2 < ? AND c3 LIKE ?))";
2628 @bind = (1234, 100, "foo%");
2630 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2631 are expressed in the same way. Of course the C<$sub_stmt> and
2632 its associated bind values can be generated through a former call
2635 my ($sub_stmt, @sub_bind)
2636 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2637 c3 => {-like => "foo%"}});
2640 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2643 In the examples above, the subquery was used as an operator on a column;
2644 but the same principle also applies for a clause within the main C<%where>
2645 hash, like an EXISTS subquery:
2647 my ($sub_stmt, @sub_bind)
2648 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2649 my %where = ( -and => [
2651 \["EXISTS ($sub_stmt)" => @sub_bind],
2656 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2657 WHERE c1 = ? AND c2 > t0.c0))";
2661 Observe that the condition on C<c2> in the subquery refers to
2662 column C<t0.c0> of the main query: this is I<not> a bind
2663 value, so we have to express it through a scalar ref.
2664 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2665 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2666 what we wanted here.
2668 Finally, here is an example where a subquery is used
2669 for expressing unary negation:
2671 my ($sub_stmt, @sub_bind)
2672 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2673 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2675 lname => {like => '%son%'},
2676 \["NOT ($sub_stmt)" => @sub_bind],
2681 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2682 @bind = ('%son%', 10, 20)
2684 =head3 Deprecated usage of Literal SQL
2686 Below are some examples of archaic use of literal SQL. It is shown only as
2687 reference for those who deal with legacy code. Each example has a much
2688 better, cleaner and safer alternative that users should opt for in new code.
2694 my %where = ( requestor => \'IS NOT NULL' )
2696 $stmt = "WHERE requestor IS NOT NULL"
2698 This used to be the way of generating NULL comparisons, before the handling
2699 of C<undef> got formalized. For new code please use the superior syntax as
2700 described in L</Tests for NULL values>.
2704 my %where = ( requestor => \'= submitter' )
2706 $stmt = "WHERE requestor = submitter"
2708 This used to be the only way to compare columns. Use the superior L</-ident>
2709 method for all new code. For example an identifier declared in such a way
2710 will be properly quoted if L</quote_char> is properly set, while the legacy
2711 form will remain as supplied.
2715 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2717 $stmt = "WHERE completed > ? AND is_ready"
2718 @bind = ('2012-12-21')
2720 Using an empty string literal used to be the only way to express a boolean.
2721 For all new code please use the much more readable
2722 L<-bool|/Unary operators: bool> operator.
2728 These pages could go on for a while, since the nesting of the data
2729 structures this module can handle are pretty much unlimited (the
2730 module implements the C<WHERE> expansion as a recursive function
2731 internally). Your best bet is to "play around" with the module a
2732 little to see how the data structures behave, and choose the best
2733 format for your data based on that.
2735 And of course, all the values above will probably be replaced with
2736 variables gotten from forms or the command line. After all, if you
2737 knew everything ahead of time, you wouldn't have to worry about
2738 dynamically-generating SQL and could just hardwire it into your
2741 =head1 ORDER BY CLAUSES
2743 Some functions take an order by clause. This can either be a scalar (just a
2744 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2745 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2748 Given | Will Generate
2749 ---------------------------------------------------------------
2751 'colA' | ORDER BY colA
2753 [qw/colA colB/] | ORDER BY colA, colB
2755 {-asc => 'colA'} | ORDER BY colA ASC
2757 {-desc => 'colB'} | ORDER BY colB DESC
2759 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2761 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2763 \'colA DESC' | ORDER BY colA DESC
2765 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2766 | /* ...with $x bound to ? */
2769 { -asc => 'colA' }, | colA ASC,
2770 { -desc => [qw/colB/] }, | colB DESC,
2771 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2772 \'colE DESC', | colE DESC,
2773 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2774 ] | /* ...with $x bound to ? */
2775 ===============================================================
2779 =head1 SPECIAL OPERATORS
2781 my $sqlmaker = SQL::Abstract->new(special_ops => [
2785 my ($self, $field, $op, $arg) = @_;
2791 handler => 'method_name',
2795 A "special operator" is a SQL syntactic clause that can be
2796 applied to a field, instead of a usual binary operator.
2799 WHERE field IN (?, ?, ?)
2800 WHERE field BETWEEN ? AND ?
2801 WHERE MATCH(field) AGAINST (?, ?)
2803 Special operators IN and BETWEEN are fairly standard and therefore
2804 are builtin within C<SQL::Abstract> (as the overridable methods
2805 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2806 like the MATCH .. AGAINST example above which is specific to MySQL,
2807 you can write your own operator handlers - supply a C<special_ops>
2808 argument to the C<new> method. That argument takes an arrayref of
2809 operator definitions; each operator definition is a hashref with two
2816 the regular expression to match the operator
2820 Either a coderef or a plain scalar method name. In both cases
2821 the expected return is C<< ($sql, @bind) >>.
2823 When supplied with a method name, it is simply called on the
2824 L<SQL::Abstract> object as:
2826 $self->$method_name($field, $op, $arg)
2830 $field is the LHS of the operator
2831 $op is the part that matched the handler regex
2834 When supplied with a coderef, it is called as:
2836 $coderef->($self, $field, $op, $arg)
2841 For example, here is an implementation
2842 of the MATCH .. AGAINST syntax for MySQL
2844 my $sqlmaker = SQL::Abstract->new(special_ops => [
2846 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2847 {regex => qr/^match$/i,
2849 my ($self, $field, $op, $arg) = @_;
2850 $arg = [$arg] if not ref $arg;
2851 my $label = $self->_quote($field);
2852 my ($placeholder) = $self->_convert('?');
2853 my $placeholders = join ", ", (($placeholder) x @$arg);
2854 my $sql = $self->_sqlcase('match') . " ($label) "
2855 . $self->_sqlcase('against') . " ($placeholders) ";
2856 my @bind = $self->_bindtype($field, @$arg);
2857 return ($sql, @bind);
2864 =head1 UNARY OPERATORS
2866 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2870 my ($self, $op, $arg) = @_;
2876 handler => 'method_name',
2880 A "unary operator" is a SQL syntactic clause that can be
2881 applied to a field - the operator goes before the field
2883 You can write your own operator handlers - supply a C<unary_ops>
2884 argument to the C<new> method. That argument takes an arrayref of
2885 operator definitions; each operator definition is a hashref with two
2892 the regular expression to match the operator
2896 Either a coderef or a plain scalar method name. In both cases
2897 the expected return is C<< $sql >>.
2899 When supplied with a method name, it is simply called on the
2900 L<SQL::Abstract> object as:
2902 $self->$method_name($op, $arg)
2906 $op is the part that matched the handler regex
2907 $arg is the RHS or argument of the operator
2909 When supplied with a coderef, it is called as:
2911 $coderef->($self, $op, $arg)
2919 Thanks to some benchmarking by Mark Stosberg, it turns out that
2920 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2921 I must admit this wasn't an intentional design issue, but it's a
2922 byproduct of the fact that you get to control your C<DBI> handles
2925 To maximize performance, use a code snippet like the following:
2927 # prepare a statement handle using the first row
2928 # and then reuse it for the rest of the rows
2930 for my $href (@array_of_hashrefs) {
2931 $stmt ||= $sql->insert('table', $href);
2932 $sth ||= $dbh->prepare($stmt);
2933 $sth->execute($sql->values($href));
2936 The reason this works is because the keys in your C<$href> are sorted
2937 internally by B<SQL::Abstract>. Thus, as long as your data retains
2938 the same structure, you only have to generate the SQL the first time
2939 around. On subsequent queries, simply use the C<values> function provided
2940 by this module to return your values in the correct order.
2942 However this depends on the values having the same type - if, for
2943 example, the values of a where clause may either have values
2944 (resulting in sql of the form C<column = ?> with a single bind
2945 value), or alternatively the values might be C<undef> (resulting in
2946 sql of the form C<column IS NULL> with no bind value) then the
2947 caching technique suggested will not work.
2951 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2952 really like this part (I do, at least). Building up a complex query
2953 can be as simple as the following:
2960 use CGI::FormBuilder;
2963 my $form = CGI::FormBuilder->new(...);
2964 my $sql = SQL::Abstract->new;
2966 if ($form->submitted) {
2967 my $field = $form->field;
2968 my $id = delete $field->{id};
2969 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2972 Of course, you would still have to connect using C<DBI> to run the
2973 query, but the point is that if you make your form look like your
2974 table, the actual query script can be extremely simplistic.
2976 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2977 a fast interface to returning and formatting data. I frequently
2978 use these three modules together to write complex database query
2979 apps in under 50 lines.
2981 =head1 HOW TO CONTRIBUTE
2983 Contributions are always welcome, in all usable forms (we especially
2984 welcome documentation improvements). The delivery methods include git-
2985 or unified-diff formatted patches, GitHub pull requests, or plain bug
2986 reports either via RT or the Mailing list. Contributors are generally
2987 granted full access to the official repository after their first several
2988 patches pass successful review.
2990 This project is maintained in a git repository. The code and related tools are
2991 accessible at the following locations:
2995 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2997 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2999 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3001 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3007 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3008 Great care has been taken to preserve the I<published> behavior
3009 documented in previous versions in the 1.* family; however,
3010 some features that were previously undocumented, or behaved
3011 differently from the documentation, had to be changed in order
3012 to clarify the semantics. Hence, client code that was relying
3013 on some dark areas of C<SQL::Abstract> v1.*
3014 B<might behave differently> in v1.50.
3016 The main changes are:
3022 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3026 support for the { operator => \"..." } construct (to embed literal SQL)
3030 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3034 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3038 defensive programming: check arguments
3042 fixed bug with global logic, which was previously implemented
3043 through global variables yielding side-effects. Prior versions would
3044 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3045 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3046 Now this is interpreted
3047 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3052 fixed semantics of _bindtype on array args
3056 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3057 we just avoid shifting arrays within that tree.
3061 dropped the C<_modlogic> function
3065 =head1 ACKNOWLEDGEMENTS
3067 There are a number of individuals that have really helped out with
3068 this module. Unfortunately, most of them submitted bugs via CPAN
3069 so I have no idea who they are! But the people I do know are:
3071 Ash Berlin (order_by hash term support)
3072 Matt Trout (DBIx::Class support)
3073 Mark Stosberg (benchmarking)
3074 Chas Owens (initial "IN" operator support)
3075 Philip Collins (per-field SQL functions)
3076 Eric Kolve (hashref "AND" support)
3077 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3078 Dan Kubb (support for "quote_char" and "name_sep")
3079 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3080 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3081 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3082 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3083 Oliver Charles (support for "RETURNING" after "INSERT")
3089 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3093 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3095 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3097 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3098 While not an official support venue, C<DBIx::Class> makes heavy use of
3099 C<SQL::Abstract>, and as such list members there are very familiar with
3100 how to create queries.
3104 This module is free software; you may copy this under the same
3105 terms as perl itself (either the GNU General Public License or
3106 the Artistic License)