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)
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 ? "( ${_} )" : $_), join(
1025 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
1030 map @{$_}[1..$#$_], @parts
1037 my ($self, $rest) = @_;
1038 my ($func, @args) = @$rest;
1042 push @arg_sql, shift @x;
1044 } map [ $self->_render_expr($_) ], @args;
1045 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1049 my ($self, $bind) = @_;
1050 return ($self->_convert('?'), $self->_bindtype(@$bind));
1053 sub _render_literal {
1054 my ($self, $literal) = @_;
1055 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1059 # Some databases (SQLite) treat col IN (1, 2) different from
1060 # col IN ( (1, 2) ). Use this to strip all outer parens while
1061 # adding them back in the corresponding method
1062 sub _open_outer_paren {
1063 my ($self, $sql) = @_;
1065 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1067 # there are closing parens inside, need the heavy duty machinery
1068 # to reevaluate the extraction starting from $sql (full reevaluation)
1069 if ($inner =~ /\)/) {
1070 require Text::Balanced;
1072 my (undef, $remainder) = do {
1073 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1075 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1078 # the entire expression needs to be a balanced bracketed thing
1079 # (after an extract no remainder sans trailing space)
1080 last if defined $remainder and $remainder =~ /\S/;
1090 #======================================================================
1092 #======================================================================
1094 sub _expand_order_by {
1095 my ($self, $arg) = @_;
1097 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1099 my $expander = sub {
1100 my ($self, $dir, $expr) = @_;
1101 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1102 foreach my $arg (@to_expand) {
1106 and grep /^-(asc|desc)$/, keys %$arg
1108 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1111 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1112 map $self->_expand_expr($_, undef, -ident),
1113 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1114 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1117 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1118 sub { shift->$expander(asc => @_) },
1119 sub { shift->$expander(desc => @_) },
1122 return $self->$expander(undef, $arg);
1126 my ($self, $arg) = @_;
1128 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1130 my ($sql, @bind) = $self->_render_expr($expanded);
1132 return '' unless length($sql);
1134 my $final_sql = $self->_sqlcase(' order by ').$sql;
1136 return wantarray ? ($final_sql, @bind) : $final_sql;
1139 # _order_by no longer needs to call this so doesn't but DBIC uses it.
1141 sub _order_by_chunks {
1142 my ($self, $arg) = @_;
1144 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1146 return $self->_chunkify_order_by($expanded);
1149 sub _chunkify_order_by {
1150 my ($self, $expanded) = @_;
1152 return grep length, $self->_render_expr($expanded)
1153 if $expanded->{-ident} or @{$expanded->{-literal}||[]} == 1;
1156 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1157 if ($op->[0] eq ',') {
1158 return map $self->_chunkify_order_by($_), @{$op}[1..$#$op];
1161 return [ $self->_render_expr($_) ];
1165 #======================================================================
1166 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1167 #======================================================================
1172 ($self->_render_expr(
1173 $self->_expand_maybe_list_expr($from, undef, -ident)
1178 #======================================================================
1180 #======================================================================
1182 sub _expand_maybe_list_expr {
1183 my ($self, $expr, $logic, $default) = @_;
1185 if (ref($expr) eq 'ARRAY') {
1187 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1194 return $self->_expand_expr($e, $logic, $default);
1197 # highly optimized, as it's called way too often
1199 # my ($self, $label) = @_;
1201 return '' unless defined $_[1];
1202 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1203 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1205 unless ($_[0]->{quote_char}) {
1206 if (ref($_[1]) eq 'ARRAY') {
1207 return join($_[0]->{name_sep}||'.', @{$_[1]});
1209 $_[0]->_assert_pass_injection_guard($_[1]);
1214 my $qref = ref $_[0]->{quote_char};
1216 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1217 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1218 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1220 my $esc = $_[0]->{escape_char} || $r;
1222 # parts containing * are naturally unquoted
1224 $_[0]->{name_sep}||'',
1228 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1230 (ref($_[1]) eq 'ARRAY'
1234 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1242 # Conversion, if applicable
1244 #my ($self, $arg) = @_;
1245 if ($_[0]->{convert_where}) {
1246 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1253 #my ($self, $col, @vals) = @_;
1254 # called often - tighten code
1255 return $_[0]->{bindtype} eq 'columns'
1256 ? map {[$_[1], $_]} @_[2 .. $#_]
1261 # Dies if any element of @bind is not in [colname => value] format
1262 # if bindtype is 'columns'.
1263 sub _assert_bindval_matches_bindtype {
1264 # my ($self, @bind) = @_;
1266 if ($self->{bindtype} eq 'columns') {
1268 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1269 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1275 sub _join_sql_clauses {
1276 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1278 if (@$clauses_aref > 1) {
1279 my $join = " " . $self->_sqlcase($logic) . " ";
1280 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1281 return ($sql, @$bind_aref);
1283 elsif (@$clauses_aref) {
1284 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1287 return (); # if no SQL, ignore @$bind_aref
1292 # Fix SQL case, if so requested
1294 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1295 # don't touch the argument ... crooked logic, but let's not change it!
1296 return $_[0]->{case} ? $_[1] : uc($_[1]);
1300 #======================================================================
1301 # DISPATCHING FROM REFKIND
1302 #======================================================================
1305 my ($self, $data) = @_;
1307 return 'UNDEF' unless defined $data;
1309 # blessed objects are treated like scalars
1310 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1312 return 'SCALAR' unless $ref;
1315 while ($ref eq 'REF') {
1317 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1321 return ($ref||'SCALAR') . ('REF' x $n_steps);
1325 my ($self, $data) = @_;
1326 my @try = ($self->_refkind($data));
1327 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1328 push @try, 'FALLBACK';
1332 sub _METHOD_FOR_refkind {
1333 my ($self, $meth_prefix, $data) = @_;
1336 for (@{$self->_try_refkind($data)}) {
1337 $method = $self->can($meth_prefix."_".$_)
1341 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1345 sub _SWITCH_refkind {
1346 my ($self, $data, $dispatch_table) = @_;
1349 for (@{$self->_try_refkind($data)}) {
1350 $coderef = $dispatch_table->{$_}
1354 puke "no dispatch entry for ".$self->_refkind($data)
1363 #======================================================================
1364 # VALUES, GENERATE, AUTOLOAD
1365 #======================================================================
1367 # LDNOTE: original code from nwiger, didn't touch code in that section
1368 # I feel the AUTOLOAD stuff should not be the default, it should
1369 # only be activated on explicit demand by user.
1373 my $data = shift || return;
1374 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1375 unless ref $data eq 'HASH';
1378 foreach my $k (sort keys %$data) {
1379 my $v = $data->{$k};
1380 $self->_SWITCH_refkind($v, {
1382 if ($self->{array_datatypes}) { # array datatype
1383 push @all_bind, $self->_bindtype($k, $v);
1385 else { # literal SQL with bind
1386 my ($sql, @bind) = @$v;
1387 $self->_assert_bindval_matches_bindtype(@bind);
1388 push @all_bind, @bind;
1391 ARRAYREFREF => sub { # literal SQL with bind
1392 my ($sql, @bind) = @${$v};
1393 $self->_assert_bindval_matches_bindtype(@bind);
1394 push @all_bind, @bind;
1396 SCALARREF => sub { # literal SQL without bind
1398 SCALAR_or_UNDEF => sub {
1399 push @all_bind, $self->_bindtype($k, $v);
1410 my(@sql, @sqlq, @sqlv);
1414 if ($ref eq 'HASH') {
1415 for my $k (sort keys %$_) {
1418 my $label = $self->_quote($k);
1419 if ($r eq 'ARRAY') {
1420 # literal SQL with bind
1421 my ($sql, @bind) = @$v;
1422 $self->_assert_bindval_matches_bindtype(@bind);
1423 push @sqlq, "$label = $sql";
1425 } elsif ($r eq 'SCALAR') {
1426 # literal SQL without bind
1427 push @sqlq, "$label = $$v";
1429 push @sqlq, "$label = ?";
1430 push @sqlv, $self->_bindtype($k, $v);
1433 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1434 } elsif ($ref eq 'ARRAY') {
1435 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1438 if ($r eq 'ARRAY') { # literal SQL with bind
1439 my ($sql, @bind) = @$v;
1440 $self->_assert_bindval_matches_bindtype(@bind);
1443 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1444 # embedded literal SQL
1451 push @sql, '(' . join(', ', @sqlq) . ')';
1452 } elsif ($ref eq 'SCALAR') {
1456 # strings get case twiddled
1457 push @sql, $self->_sqlcase($_);
1461 my $sql = join ' ', @sql;
1463 # this is pretty tricky
1464 # if ask for an array, return ($stmt, @bind)
1465 # otherwise, s/?/shift @sqlv/ to put it inline
1467 return ($sql, @sqlv);
1469 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1470 ref $d ? $d->[1] : $d/e;
1479 # This allows us to check for a local, then _form, attr
1481 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1482 return $self->generate($name, @_);
1493 SQL::Abstract - Generate SQL from Perl data structures
1499 my $sql = SQL::Abstract->new;
1501 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1503 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1505 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1507 my($stmt, @bind) = $sql->delete($table, \%where);
1509 # Then, use these in your DBI statements
1510 my $sth = $dbh->prepare($stmt);
1511 $sth->execute(@bind);
1513 # Just generate the WHERE clause
1514 my($stmt, @bind) = $sql->where(\%where, $order);
1516 # Return values in the same order, for hashed queries
1517 # See PERFORMANCE section for more details
1518 my @bind = $sql->values(\%fieldvals);
1522 This module was inspired by the excellent L<DBIx::Abstract>.
1523 However, in using that module I found that what I really wanted
1524 to do was generate SQL, but still retain complete control over my
1525 statement handles and use the DBI interface. So, I set out to
1526 create an abstract SQL generation module.
1528 While based on the concepts used by L<DBIx::Abstract>, there are
1529 several important differences, especially when it comes to WHERE
1530 clauses. I have modified the concepts used to make the SQL easier
1531 to generate from Perl data structures and, IMO, more intuitive.
1532 The underlying idea is for this module to do what you mean, based
1533 on the data structures you provide it. The big advantage is that
1534 you don't have to modify your code every time your data changes,
1535 as this module figures it out.
1537 To begin with, an SQL INSERT is as easy as just specifying a hash
1538 of C<key=value> pairs:
1541 name => 'Jimbo Bobson',
1542 phone => '123-456-7890',
1543 address => '42 Sister Lane',
1544 city => 'St. Louis',
1545 state => 'Louisiana',
1548 The SQL can then be generated with this:
1550 my($stmt, @bind) = $sql->insert('people', \%data);
1552 Which would give you something like this:
1554 $stmt = "INSERT INTO people
1555 (address, city, name, phone, state)
1556 VALUES (?, ?, ?, ?, ?)";
1557 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1558 '123-456-7890', 'Louisiana');
1560 These are then used directly in your DBI code:
1562 my $sth = $dbh->prepare($stmt);
1563 $sth->execute(@bind);
1565 =head2 Inserting and Updating Arrays
1567 If your database has array types (like for example Postgres),
1568 activate the special option C<< array_datatypes => 1 >>
1569 when creating the C<SQL::Abstract> object.
1570 Then you may use an arrayref to insert and update database array types:
1572 my $sql = SQL::Abstract->new(array_datatypes => 1);
1574 planets => [qw/Mercury Venus Earth Mars/]
1577 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1581 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1583 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1586 =head2 Inserting and Updating SQL
1588 In order to apply SQL functions to elements of your C<%data> you may
1589 specify a reference to an arrayref for the given hash value. For example,
1590 if you need to execute the Oracle C<to_date> function on a value, you can
1591 say something like this:
1595 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1598 The first value in the array is the actual SQL. Any other values are
1599 optional and would be included in the bind values array. This gives
1602 my($stmt, @bind) = $sql->insert('people', \%data);
1604 $stmt = "INSERT INTO people (name, date_entered)
1605 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1606 @bind = ('Bill', '03/02/2003');
1608 An UPDATE is just as easy, all you change is the name of the function:
1610 my($stmt, @bind) = $sql->update('people', \%data);
1612 Notice that your C<%data> isn't touched; the module will generate
1613 the appropriately quirky SQL for you automatically. Usually you'll
1614 want to specify a WHERE clause for your UPDATE, though, which is
1615 where handling C<%where> hashes comes in handy...
1617 =head2 Complex where statements
1619 This module can generate pretty complicated WHERE statements
1620 easily. For example, simple C<key=value> pairs are taken to mean
1621 equality, and if you want to see if a field is within a set
1622 of values, you can use an arrayref. Let's say we wanted to
1623 SELECT some data based on this criteria:
1626 requestor => 'inna',
1627 worker => ['nwiger', 'rcwe', 'sfz'],
1628 status => { '!=', 'completed' }
1631 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1633 The above would give you something like this:
1635 $stmt = "SELECT * FROM tickets WHERE
1636 ( requestor = ? ) AND ( status != ? )
1637 AND ( worker = ? OR worker = ? OR worker = ? )";
1638 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1640 Which you could then use in DBI code like so:
1642 my $sth = $dbh->prepare($stmt);
1643 $sth->execute(@bind);
1649 The methods are simple. There's one for every major SQL operation,
1650 and a constructor you use first. The arguments are specified in a
1651 similar order for each method (table, then fields, then a where
1652 clause) to try and simplify things.
1654 =head2 new(option => 'value')
1656 The C<new()> function takes a list of options and values, and returns
1657 a new B<SQL::Abstract> object which can then be used to generate SQL
1658 through the methods below. The options accepted are:
1664 If set to 'lower', then SQL will be generated in all lowercase. By
1665 default SQL is generated in "textbook" case meaning something like:
1667 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1669 Any setting other than 'lower' is ignored.
1673 This determines what the default comparison operator is. By default
1674 it is C<=>, meaning that a hash like this:
1676 %where = (name => 'nwiger', email => 'nate@wiger.org');
1678 Will generate SQL like this:
1680 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1682 However, you may want loose comparisons by default, so if you set
1683 C<cmp> to C<like> you would get SQL such as:
1685 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1687 You can also override the comparison on an individual basis - see
1688 the huge section on L</"WHERE CLAUSES"> at the bottom.
1690 =item sqltrue, sqlfalse
1692 Expressions for inserting boolean values within SQL statements.
1693 By default these are C<1=1> and C<1=0>. They are used
1694 by the special operators C<-in> and C<-not_in> for generating
1695 correct SQL even when the argument is an empty array (see below).
1699 This determines the default logical operator for multiple WHERE
1700 statements in arrays or hashes. If absent, the default logic is "or"
1701 for arrays, and "and" for hashes. This means that a WHERE
1705 event_date => {'>=', '2/13/99'},
1706 event_date => {'<=', '4/24/03'},
1709 will generate SQL like this:
1711 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1713 This is probably not what you want given this query, though (look
1714 at the dates). To change the "OR" to an "AND", simply specify:
1716 my $sql = SQL::Abstract->new(logic => 'and');
1718 Which will change the above C<WHERE> to:
1720 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1722 The logic can also be changed locally by inserting
1723 a modifier in front of an arrayref:
1725 @where = (-and => [event_date => {'>=', '2/13/99'},
1726 event_date => {'<=', '4/24/03'} ]);
1728 See the L</"WHERE CLAUSES"> section for explanations.
1732 This will automatically convert comparisons using the specified SQL
1733 function for both column and value. This is mostly used with an argument
1734 of C<upper> or C<lower>, so that the SQL will have the effect of
1735 case-insensitive "searches". For example, this:
1737 $sql = SQL::Abstract->new(convert => 'upper');
1738 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1740 Will turn out the following SQL:
1742 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1744 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1745 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1746 not validate this option; it will just pass through what you specify verbatim).
1750 This is a kludge because many databases suck. For example, you can't
1751 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1752 Instead, you have to use C<bind_param()>:
1754 $sth->bind_param(1, 'reg data');
1755 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1757 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1758 which loses track of which field each slot refers to. Fear not.
1760 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1761 Currently, you can specify either C<normal> (default) or C<columns>. If you
1762 specify C<columns>, you will get an array that looks like this:
1764 my $sql = SQL::Abstract->new(bindtype => 'columns');
1765 my($stmt, @bind) = $sql->insert(...);
1768 [ 'column1', 'value1' ],
1769 [ 'column2', 'value2' ],
1770 [ 'column3', 'value3' ],
1773 You can then iterate through this manually, using DBI's C<bind_param()>.
1775 $sth->prepare($stmt);
1778 my($col, $data) = @$_;
1779 if ($col eq 'details' || $col eq 'comments') {
1780 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1781 } elsif ($col eq 'image') {
1782 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1784 $sth->bind_param($i, $data);
1788 $sth->execute; # execute without @bind now
1790 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1791 Basically, the advantage is still that you don't have to care which fields
1792 are or are not included. You could wrap that above C<for> loop in a simple
1793 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1794 get a layer of abstraction over manual SQL specification.
1796 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1797 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1798 will expect the bind values in this format.
1802 This is the character that a table or column name will be quoted
1803 with. By default this is an empty string, but you could set it to
1804 the character C<`>, to generate SQL like this:
1806 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1808 Alternatively, you can supply an array ref of two items, the first being the left
1809 hand quote character, and the second the right hand quote character. For
1810 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1811 that generates SQL like this:
1813 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1815 Quoting is useful if you have tables or columns names that are reserved
1816 words in your database's SQL dialect.
1820 This is the character that will be used to escape L</quote_char>s appearing
1821 in an identifier before it has been quoted.
1823 The parameter default in case of a single L</quote_char> character is the quote
1826 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1827 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1828 of the B<opening (left)> L</quote_char> within the identifier are currently left
1829 untouched. The default for opening-closing-style quotes may change in future
1830 versions, thus you are B<strongly encouraged> to specify the escape character
1835 This is the character that separates a table and column name. It is
1836 necessary to specify this when the C<quote_char> option is selected,
1837 so that tables and column names can be individually quoted like this:
1839 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1841 =item injection_guard
1843 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1844 column name specified in a query structure. This is a safety mechanism to avoid
1845 injection attacks when mishandling user input e.g.:
1847 my %condition_as_column_value_pairs = get_values_from_user();
1848 $sqla->select( ... , \%condition_as_column_value_pairs );
1850 If the expression matches an exception is thrown. Note that literal SQL
1851 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1853 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1855 =item array_datatypes
1857 When this option is true, arrayrefs in INSERT or UPDATE are
1858 interpreted as array datatypes and are passed directly
1860 When this option is false, arrayrefs are interpreted
1861 as literal SQL, just like refs to arrayrefs
1862 (but this behavior is for backwards compatibility; when writing
1863 new queries, use the "reference to arrayref" syntax
1869 Takes a reference to a list of "special operators"
1870 to extend the syntax understood by L<SQL::Abstract>.
1871 See section L</"SPECIAL OPERATORS"> for details.
1875 Takes a reference to a list of "unary operators"
1876 to extend the syntax understood by L<SQL::Abstract>.
1877 See section L</"UNARY OPERATORS"> for details.
1883 =head2 insert($table, \@values || \%fieldvals, \%options)
1885 This is the simplest function. You simply give it a table name
1886 and either an arrayref of values or hashref of field/value pairs.
1887 It returns an SQL INSERT statement and a list of bind values.
1888 See the sections on L</"Inserting and Updating Arrays"> and
1889 L</"Inserting and Updating SQL"> for information on how to insert
1890 with those data types.
1892 The optional C<\%options> hash reference may contain additional
1893 options to generate the insert SQL. Currently supported options
1900 Takes either a scalar of raw SQL fields, or an array reference of
1901 field names, and adds on an SQL C<RETURNING> statement at the end.
1902 This allows you to return data generated by the insert statement
1903 (such as row IDs) without performing another C<SELECT> statement.
1904 Note, however, this is not part of the SQL standard and may not
1905 be supported by all database engines.
1909 =head2 update($table, \%fieldvals, \%where, \%options)
1911 This takes a table, hashref of field/value pairs, and an optional
1912 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1914 See the sections on L</"Inserting and Updating Arrays"> and
1915 L</"Inserting and Updating SQL"> for information on how to insert
1916 with those data types.
1918 The optional C<\%options> hash reference may contain additional
1919 options to generate the update SQL. Currently supported options
1926 See the C<returning> option to
1927 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1931 =head2 select($source, $fields, $where, $order)
1933 This returns a SQL SELECT statement and associated list of bind values, as
1934 specified by the arguments:
1940 Specification of the 'FROM' part of the statement.
1941 The argument can be either a plain scalar (interpreted as a table
1942 name, will be quoted), or an arrayref (interpreted as a list
1943 of table names, joined by commas, quoted), or a scalarref
1944 (literal SQL, not quoted).
1948 Specification of the list of fields to retrieve from
1950 The argument can be either an arrayref (interpreted as a list
1951 of field names, will be joined by commas and quoted), or a
1952 plain scalar (literal SQL, not quoted).
1953 Please observe that this API is not as flexible as that of
1954 the first argument C<$source>, for backwards compatibility reasons.
1958 Optional argument to specify the WHERE part of the query.
1959 The argument is most often a hashref, but can also be
1960 an arrayref or plain scalar --
1961 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1965 Optional argument to specify the ORDER BY part of the query.
1966 The argument can be a scalar, a hashref or an arrayref
1967 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1973 =head2 delete($table, \%where, \%options)
1975 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1976 It returns an SQL DELETE statement and list of bind values.
1978 The optional C<\%options> hash reference may contain additional
1979 options to generate the delete SQL. Currently supported options
1986 See the C<returning> option to
1987 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1991 =head2 where(\%where, $order)
1993 This is used to generate just the WHERE clause. For example,
1994 if you have an arbitrary data structure and know what the
1995 rest of your SQL is going to look like, but want an easy way
1996 to produce a WHERE clause, use this. It returns an SQL WHERE
1997 clause and list of bind values.
2000 =head2 values(\%data)
2002 This just returns the values from the hash C<%data>, in the same
2003 order that would be returned from any of the other above queries.
2004 Using this allows you to markedly speed up your queries if you
2005 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2007 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2009 Warning: This is an experimental method and subject to change.
2011 This returns arbitrarily generated SQL. It's a really basic shortcut.
2012 It will return two different things, depending on return context:
2014 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2015 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2017 These would return the following:
2019 # First calling form
2020 $stmt = "CREATE TABLE test (?, ?)";
2021 @bind = (field1, field2);
2023 # Second calling form
2024 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2026 Depending on what you're trying to do, it's up to you to choose the correct
2027 format. In this example, the second form is what you would want.
2031 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2035 ALTER SESSION SET nls_date_format = 'MM/YY'
2037 You get the idea. Strings get their case twiddled, but everything
2038 else remains verbatim.
2040 =head1 EXPORTABLE FUNCTIONS
2042 =head2 is_plain_value
2044 Determines if the supplied argument is a plain value as understood by this
2049 =item * The value is C<undef>
2051 =item * The value is a non-reference
2053 =item * The value is an object with stringification overloading
2055 =item * The value is of the form C<< { -value => $anything } >>
2059 On failure returns C<undef>, on success returns a B<scalar> reference
2060 to the original supplied argument.
2066 The stringification overloading detection is rather advanced: it takes
2067 into consideration not only the presence of a C<""> overload, but if that
2068 fails also checks for enabled
2069 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2070 on either C<0+> or C<bool>.
2072 Unfortunately testing in the field indicates that this
2073 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2074 but only when very large numbers of stringifying objects are involved.
2075 At the time of writing ( Sep 2014 ) there is no clear explanation of
2076 the direct cause, nor is there a manageably small test case that reliably
2077 reproduces the problem.
2079 If you encounter any of the following exceptions in B<random places within
2080 your application stack> - this module may be to blame:
2082 Operation "ne": no method found,
2083 left argument in overloaded package <something>,
2084 right argument in overloaded package <something>
2088 Stub found while resolving method "???" overloading """" in package <something>
2090 If you fall victim to the above - please attempt to reduce the problem
2091 to something that could be sent to the L<SQL::Abstract developers
2092 |DBIx::Class/GETTING HELP/SUPPORT>
2093 (either publicly or privately). As a workaround in the meantime you can
2094 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2095 value, which will most likely eliminate your problem (at the expense of
2096 not being able to properly detect exotic forms of stringification).
2098 This notice and environment variable will be removed in a future version,
2099 as soon as the underlying problem is found and a reliable workaround is
2104 =head2 is_literal_value
2106 Determines if the supplied argument is a literal value as understood by this
2111 =item * C<\$sql_string>
2113 =item * C<\[ $sql_string, @bind_values ]>
2117 On failure returns C<undef>, on success returns an B<array> reference
2118 containing the unpacked version of the supplied literal SQL and bind values.
2120 =head1 WHERE CLAUSES
2124 This module uses a variation on the idea from L<DBIx::Abstract>. It
2125 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2126 module is that things in arrays are OR'ed, and things in hashes
2129 The easiest way to explain is to show lots of examples. After
2130 each C<%where> hash shown, it is assumed you used:
2132 my($stmt, @bind) = $sql->where(\%where);
2134 However, note that the C<%where> hash can be used directly in any
2135 of the other functions as well, as described above.
2137 =head2 Key-value pairs
2139 So, let's get started. To begin, a simple hash:
2143 status => 'completed'
2146 Is converted to SQL C<key = val> statements:
2148 $stmt = "WHERE user = ? AND status = ?";
2149 @bind = ('nwiger', 'completed');
2151 One common thing I end up doing is having a list of values that
2152 a field can be in. To do this, simply specify a list inside of
2157 status => ['assigned', 'in-progress', 'pending'];
2160 This simple code will create the following:
2162 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2163 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2165 A field associated to an empty arrayref will be considered a
2166 logical false and will generate 0=1.
2168 =head2 Tests for NULL values
2170 If the value part is C<undef> then this is converted to SQL <IS NULL>
2179 $stmt = "WHERE user = ? AND status IS NULL";
2182 To test if a column IS NOT NULL:
2186 status => { '!=', undef },
2189 =head2 Specific comparison operators
2191 If you want to specify a different type of operator for your comparison,
2192 you can use a hashref for a given column:
2196 status => { '!=', 'completed' }
2199 Which would generate:
2201 $stmt = "WHERE user = ? AND status != ?";
2202 @bind = ('nwiger', 'completed');
2204 To test against multiple values, just enclose the values in an arrayref:
2206 status => { '=', ['assigned', 'in-progress', 'pending'] };
2208 Which would give you:
2210 "WHERE status = ? OR status = ? OR status = ?"
2213 The hashref can also contain multiple pairs, in which case it is expanded
2214 into an C<AND> of its elements:
2218 status => { '!=', 'completed', -not_like => 'pending%' }
2221 # Or more dynamically, like from a form
2222 $where{user} = 'nwiger';
2223 $where{status}{'!='} = 'completed';
2224 $where{status}{'-not_like'} = 'pending%';
2226 # Both generate this
2227 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2228 @bind = ('nwiger', 'completed', 'pending%');
2231 To get an OR instead, you can combine it with the arrayref idea:
2235 priority => [ { '=', 2 }, { '>', 5 } ]
2238 Which would generate:
2240 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2241 @bind = ('2', '5', 'nwiger');
2243 If you want to include literal SQL (with or without bind values), just use a
2244 scalar reference or reference to an arrayref as the value:
2247 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2248 date_expires => { '<' => \"now()" }
2251 Which would generate:
2253 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2254 @bind = ('11/26/2008');
2257 =head2 Logic and nesting operators
2259 In the example above,
2260 there is a subtle trap if you want to say something like
2261 this (notice the C<AND>):
2263 WHERE priority != ? AND priority != ?
2265 Because, in Perl you I<can't> do this:
2267 priority => { '!=' => 2, '!=' => 1 }
2269 As the second C<!=> key will obliterate the first. The solution
2270 is to use the special C<-modifier> form inside an arrayref:
2272 priority => [ -and => {'!=', 2},
2276 Normally, these would be joined by C<OR>, but the modifier tells it
2277 to use C<AND> instead. (Hint: You can use this in conjunction with the
2278 C<logic> option to C<new()> in order to change the way your queries
2279 work by default.) B<Important:> Note that the C<-modifier> goes
2280 B<INSIDE> the arrayref, as an extra first element. This will
2281 B<NOT> do what you think it might:
2283 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2285 Here is a quick list of equivalencies, since there is some overlap:
2288 status => {'!=', 'completed', 'not like', 'pending%' }
2289 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2292 status => {'=', ['assigned', 'in-progress']}
2293 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2294 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2298 =head2 Special operators: IN, BETWEEN, etc.
2300 You can also use the hashref format to compare a list of fields using the
2301 C<IN> comparison operator, by specifying the list as an arrayref:
2304 status => 'completed',
2305 reportid => { -in => [567, 2335, 2] }
2308 Which would generate:
2310 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2311 @bind = ('completed', '567', '2335', '2');
2313 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2316 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2317 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2318 'sqltrue' (by default: C<1=1>).
2320 In addition to the array you can supply a chunk of literal sql or
2321 literal sql with bind:
2324 customer => { -in => \[
2325 'SELECT cust_id FROM cust WHERE balance > ?',
2328 status => { -in => \'SELECT status_codes FROM states' },
2334 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2335 AND status IN ( SELECT status_codes FROM states )
2339 Finally, if the argument to C<-in> is not a reference, it will be
2340 treated as a single-element array.
2342 Another pair of operators is C<-between> and C<-not_between>,
2343 used with an arrayref of two values:
2347 completion_date => {
2348 -not_between => ['2002-10-01', '2003-02-06']
2354 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2356 Just like with C<-in> all plausible combinations of literal SQL
2360 start0 => { -between => [ 1, 2 ] },
2361 start1 => { -between => \["? AND ?", 1, 2] },
2362 start2 => { -between => \"lower(x) AND upper(y)" },
2363 start3 => { -between => [
2365 \["upper(?)", 'stuff' ],
2372 ( start0 BETWEEN ? AND ? )
2373 AND ( start1 BETWEEN ? AND ? )
2374 AND ( start2 BETWEEN lower(x) AND upper(y) )
2375 AND ( start3 BETWEEN lower(x) AND upper(?) )
2377 @bind = (1, 2, 1, 2, 'stuff');
2380 These are the two builtin "special operators"; but the
2381 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2383 =head2 Unary operators: bool
2385 If you wish to test against boolean columns or functions within your
2386 database you can use the C<-bool> and C<-not_bool> operators. For
2387 example to test the column C<is_user> being true and the column
2388 C<is_enabled> being false you would use:-
2392 -not_bool => 'is_enabled',
2397 WHERE is_user AND NOT is_enabled
2399 If a more complex combination is required, testing more conditions,
2400 then you should use the and/or operators:-
2405 -not_bool => { two=> { -rlike => 'bar' } },
2406 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2417 (NOT ( three = ? OR three > ? ))
2420 =head2 Nested conditions, -and/-or prefixes
2422 So far, we've seen how multiple conditions are joined with a top-level
2423 C<AND>. We can change this by putting the different conditions we want in
2424 hashes and then putting those hashes in an array. For example:
2429 status => { -like => ['pending%', 'dispatched'] },
2433 status => 'unassigned',
2437 This data structure would create the following:
2439 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2440 OR ( user = ? AND status = ? ) )";
2441 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2444 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2445 to change the logic inside:
2451 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2452 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2459 $stmt = "WHERE ( user = ?
2460 AND ( ( workhrs > ? AND geo = ? )
2461 OR ( workhrs < ? OR geo = ? ) ) )";
2462 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2464 =head3 Algebraic inconsistency, for historical reasons
2466 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2467 operator goes C<outside> of the nested structure; whereas when connecting
2468 several constraints on one column, the C<-and> operator goes
2469 C<inside> the arrayref. Here is an example combining both features:
2472 -and => [a => 1, b => 2],
2473 -or => [c => 3, d => 4],
2474 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2479 WHERE ( ( ( a = ? AND b = ? )
2480 OR ( c = ? OR d = ? )
2481 OR ( e LIKE ? AND e LIKE ? ) ) )
2483 This difference in syntax is unfortunate but must be preserved for
2484 historical reasons. So be careful: the two examples below would
2485 seem algebraically equivalent, but they are not
2488 { -like => 'foo%' },
2489 { -like => '%bar' },
2491 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2494 { col => { -like => 'foo%' } },
2495 { col => { -like => '%bar' } },
2497 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2500 =head2 Literal SQL and value type operators
2502 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2503 side" is a column name and the "right side" is a value (normally rendered as
2504 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2505 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2506 alter this behavior. There are several ways of doing so.
2510 This is a virtual operator that signals the string to its right side is an
2511 identifier (a column name) and not a value. For example to compare two
2512 columns you would write:
2515 priority => { '<', 2 },
2516 requestor => { -ident => 'submitter' },
2521 $stmt = "WHERE priority < ? AND requestor = submitter";
2524 If you are maintaining legacy code you may see a different construct as
2525 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2530 This is a virtual operator that signals that the construct to its right side
2531 is a value to be passed to DBI. This is for example necessary when you want
2532 to write a where clause against an array (for RDBMS that support such
2533 datatypes). For example:
2536 array => { -value => [1, 2, 3] }
2541 $stmt = 'WHERE array = ?';
2542 @bind = ([1, 2, 3]);
2544 Note that if you were to simply say:
2550 the result would probably not be what you wanted:
2552 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2557 Finally, sometimes only literal SQL will do. To include a random snippet
2558 of SQL verbatim, you specify it as a scalar reference. Consider this only
2559 as a last resort. Usually there is a better way. For example:
2562 priority => { '<', 2 },
2563 requestor => { -in => \'(SELECT name FROM hitmen)' },
2568 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2571 Note that in this example, you only get one bind parameter back, since
2572 the verbatim SQL is passed as part of the statement.
2576 Never use untrusted input as a literal SQL argument - this is a massive
2577 security risk (there is no way to check literal snippets for SQL
2578 injections and other nastyness). If you need to deal with untrusted input
2579 use literal SQL with placeholders as described next.
2581 =head3 Literal SQL with placeholders and bind values (subqueries)
2583 If the literal SQL to be inserted has placeholders and bind values,
2584 use a reference to an arrayref (yes this is a double reference --
2585 not so common, but perfectly legal Perl). For example, to find a date
2586 in Postgres you can use something like this:
2589 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2594 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2597 Note that you must pass the bind values in the same format as they are returned
2598 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2599 to C<columns>, you must provide the bind values in the
2600 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2601 scalar value; most commonly the column name, but you can use any scalar value
2602 (including references and blessed references), L<SQL::Abstract> will simply
2603 pass it through intact. So if C<bindtype> is set to C<columns> the above
2604 example will look like:
2607 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2610 Literal SQL is especially useful for nesting parenthesized clauses in the
2611 main SQL query. Here is a first example:
2613 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2617 bar => \["IN ($sub_stmt)" => @sub_bind],
2622 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2623 WHERE c2 < ? AND c3 LIKE ?))";
2624 @bind = (1234, 100, "foo%");
2626 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2627 are expressed in the same way. Of course the C<$sub_stmt> and
2628 its associated bind values can be generated through a former call
2631 my ($sub_stmt, @sub_bind)
2632 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2633 c3 => {-like => "foo%"}});
2636 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2639 In the examples above, the subquery was used as an operator on a column;
2640 but the same principle also applies for a clause within the main C<%where>
2641 hash, like an EXISTS subquery:
2643 my ($sub_stmt, @sub_bind)
2644 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2645 my %where = ( -and => [
2647 \["EXISTS ($sub_stmt)" => @sub_bind],
2652 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2653 WHERE c1 = ? AND c2 > t0.c0))";
2657 Observe that the condition on C<c2> in the subquery refers to
2658 column C<t0.c0> of the main query: this is I<not> a bind
2659 value, so we have to express it through a scalar ref.
2660 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2661 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2662 what we wanted here.
2664 Finally, here is an example where a subquery is used
2665 for expressing unary negation:
2667 my ($sub_stmt, @sub_bind)
2668 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2669 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2671 lname => {like => '%son%'},
2672 \["NOT ($sub_stmt)" => @sub_bind],
2677 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2678 @bind = ('%son%', 10, 20)
2680 =head3 Deprecated usage of Literal SQL
2682 Below are some examples of archaic use of literal SQL. It is shown only as
2683 reference for those who deal with legacy code. Each example has a much
2684 better, cleaner and safer alternative that users should opt for in new code.
2690 my %where = ( requestor => \'IS NOT NULL' )
2692 $stmt = "WHERE requestor IS NOT NULL"
2694 This used to be the way of generating NULL comparisons, before the handling
2695 of C<undef> got formalized. For new code please use the superior syntax as
2696 described in L</Tests for NULL values>.
2700 my %where = ( requestor => \'= submitter' )
2702 $stmt = "WHERE requestor = submitter"
2704 This used to be the only way to compare columns. Use the superior L</-ident>
2705 method for all new code. For example an identifier declared in such a way
2706 will be properly quoted if L</quote_char> is properly set, while the legacy
2707 form will remain as supplied.
2711 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2713 $stmt = "WHERE completed > ? AND is_ready"
2714 @bind = ('2012-12-21')
2716 Using an empty string literal used to be the only way to express a boolean.
2717 For all new code please use the much more readable
2718 L<-bool|/Unary operators: bool> operator.
2724 These pages could go on for a while, since the nesting of the data
2725 structures this module can handle are pretty much unlimited (the
2726 module implements the C<WHERE> expansion as a recursive function
2727 internally). Your best bet is to "play around" with the module a
2728 little to see how the data structures behave, and choose the best
2729 format for your data based on that.
2731 And of course, all the values above will probably be replaced with
2732 variables gotten from forms or the command line. After all, if you
2733 knew everything ahead of time, you wouldn't have to worry about
2734 dynamically-generating SQL and could just hardwire it into your
2737 =head1 ORDER BY CLAUSES
2739 Some functions take an order by clause. This can either be a scalar (just a
2740 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2741 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2744 Given | Will Generate
2745 ---------------------------------------------------------------
2747 'colA' | ORDER BY colA
2749 [qw/colA colB/] | ORDER BY colA, colB
2751 {-asc => 'colA'} | ORDER BY colA ASC
2753 {-desc => 'colB'} | ORDER BY colB DESC
2755 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2757 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2759 \'colA DESC' | ORDER BY colA DESC
2761 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2762 | /* ...with $x bound to ? */
2765 { -asc => 'colA' }, | colA ASC,
2766 { -desc => [qw/colB/] }, | colB DESC,
2767 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2768 \'colE DESC', | colE DESC,
2769 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2770 ] | /* ...with $x bound to ? */
2771 ===============================================================
2775 =head1 SPECIAL OPERATORS
2777 my $sqlmaker = SQL::Abstract->new(special_ops => [
2781 my ($self, $field, $op, $arg) = @_;
2787 handler => 'method_name',
2791 A "special operator" is a SQL syntactic clause that can be
2792 applied to a field, instead of a usual binary operator.
2795 WHERE field IN (?, ?, ?)
2796 WHERE field BETWEEN ? AND ?
2797 WHERE MATCH(field) AGAINST (?, ?)
2799 Special operators IN and BETWEEN are fairly standard and therefore
2800 are builtin within C<SQL::Abstract> (as the overridable methods
2801 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2802 like the MATCH .. AGAINST example above which is specific to MySQL,
2803 you can write your own operator handlers - supply a C<special_ops>
2804 argument to the C<new> method. That argument takes an arrayref of
2805 operator definitions; each operator definition is a hashref with two
2812 the regular expression to match the operator
2816 Either a coderef or a plain scalar method name. In both cases
2817 the expected return is C<< ($sql, @bind) >>.
2819 When supplied with a method name, it is simply called on the
2820 L<SQL::Abstract> object as:
2822 $self->$method_name($field, $op, $arg)
2826 $field is the LHS of the operator
2827 $op is the part that matched the handler regex
2830 When supplied with a coderef, it is called as:
2832 $coderef->($self, $field, $op, $arg)
2837 For example, here is an implementation
2838 of the MATCH .. AGAINST syntax for MySQL
2840 my $sqlmaker = SQL::Abstract->new(special_ops => [
2842 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2843 {regex => qr/^match$/i,
2845 my ($self, $field, $op, $arg) = @_;
2846 $arg = [$arg] if not ref $arg;
2847 my $label = $self->_quote($field);
2848 my ($placeholder) = $self->_convert('?');
2849 my $placeholders = join ", ", (($placeholder) x @$arg);
2850 my $sql = $self->_sqlcase('match') . " ($label) "
2851 . $self->_sqlcase('against') . " ($placeholders) ";
2852 my @bind = $self->_bindtype($field, @$arg);
2853 return ($sql, @bind);
2860 =head1 UNARY OPERATORS
2862 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2866 my ($self, $op, $arg) = @_;
2872 handler => 'method_name',
2876 A "unary operator" is a SQL syntactic clause that can be
2877 applied to a field - the operator goes before the field
2879 You can write your own operator handlers - supply a C<unary_ops>
2880 argument to the C<new> method. That argument takes an arrayref of
2881 operator definitions; each operator definition is a hashref with two
2888 the regular expression to match the operator
2892 Either a coderef or a plain scalar method name. In both cases
2893 the expected return is C<< $sql >>.
2895 When supplied with a method name, it is simply called on the
2896 L<SQL::Abstract> object as:
2898 $self->$method_name($op, $arg)
2902 $op is the part that matched the handler regex
2903 $arg is the RHS or argument of the operator
2905 When supplied with a coderef, it is called as:
2907 $coderef->($self, $op, $arg)
2915 Thanks to some benchmarking by Mark Stosberg, it turns out that
2916 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2917 I must admit this wasn't an intentional design issue, but it's a
2918 byproduct of the fact that you get to control your C<DBI> handles
2921 To maximize performance, use a code snippet like the following:
2923 # prepare a statement handle using the first row
2924 # and then reuse it for the rest of the rows
2926 for my $href (@array_of_hashrefs) {
2927 $stmt ||= $sql->insert('table', $href);
2928 $sth ||= $dbh->prepare($stmt);
2929 $sth->execute($sql->values($href));
2932 The reason this works is because the keys in your C<$href> are sorted
2933 internally by B<SQL::Abstract>. Thus, as long as your data retains
2934 the same structure, you only have to generate the SQL the first time
2935 around. On subsequent queries, simply use the C<values> function provided
2936 by this module to return your values in the correct order.
2938 However this depends on the values having the same type - if, for
2939 example, the values of a where clause may either have values
2940 (resulting in sql of the form C<column = ?> with a single bind
2941 value), or alternatively the values might be C<undef> (resulting in
2942 sql of the form C<column IS NULL> with no bind value) then the
2943 caching technique suggested will not work.
2947 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2948 really like this part (I do, at least). Building up a complex query
2949 can be as simple as the following:
2956 use CGI::FormBuilder;
2959 my $form = CGI::FormBuilder->new(...);
2960 my $sql = SQL::Abstract->new;
2962 if ($form->submitted) {
2963 my $field = $form->field;
2964 my $id = delete $field->{id};
2965 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2968 Of course, you would still have to connect using C<DBI> to run the
2969 query, but the point is that if you make your form look like your
2970 table, the actual query script can be extremely simplistic.
2972 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2973 a fast interface to returning and formatting data. I frequently
2974 use these three modules together to write complex database query
2975 apps in under 50 lines.
2977 =head1 HOW TO CONTRIBUTE
2979 Contributions are always welcome, in all usable forms (we especially
2980 welcome documentation improvements). The delivery methods include git-
2981 or unified-diff formatted patches, GitHub pull requests, or plain bug
2982 reports either via RT or the Mailing list. Contributors are generally
2983 granted full access to the official repository after their first several
2984 patches pass successful review.
2986 This project is maintained in a git repository. The code and related tools are
2987 accessible at the following locations:
2991 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2993 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2995 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2997 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3003 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3004 Great care has been taken to preserve the I<published> behavior
3005 documented in previous versions in the 1.* family; however,
3006 some features that were previously undocumented, or behaved
3007 differently from the documentation, had to be changed in order
3008 to clarify the semantics. Hence, client code that was relying
3009 on some dark areas of C<SQL::Abstract> v1.*
3010 B<might behave differently> in v1.50.
3012 The main changes are:
3018 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3022 support for the { operator => \"..." } construct (to embed literal SQL)
3026 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3030 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3034 defensive programming: check arguments
3038 fixed bug with global logic, which was previously implemented
3039 through global variables yielding side-effects. Prior versions would
3040 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3041 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3042 Now this is interpreted
3043 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3048 fixed semantics of _bindtype on array args
3052 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3053 we just avoid shifting arrays within that tree.
3057 dropped the C<_modlogic> function
3061 =head1 ACKNOWLEDGEMENTS
3063 There are a number of individuals that have really helped out with
3064 this module. Unfortunately, most of them submitted bugs via CPAN
3065 so I have no idea who they are! But the people I do know are:
3067 Ash Berlin (order_by hash term support)
3068 Matt Trout (DBIx::Class support)
3069 Mark Stosberg (benchmarking)
3070 Chas Owens (initial "IN" operator support)
3071 Philip Collins (per-field SQL functions)
3072 Eric Kolve (hashref "AND" support)
3073 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3074 Dan Kubb (support for "quote_char" and "name_sep")
3075 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3076 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3077 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3078 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3079 Oliver Charles (support for "RETURNING" after "INSERT")
3085 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3089 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3091 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3093 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3094 While not an official support venue, C<DBIx::Class> makes heavy use of
3095 C<SQL::Abstract>, and as such list members there are very familiar with
3096 how to create queries.
3100 This module is free software; you may copy this under the same
3101 terms as perl itself (either the GNU General Public License or
3102 the Artistic License)