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 $opt{user_special_ops} = [ @{$opt{special_ops} ||= []} ];
159 # regexes are applied in order, thus push after user-defines
160 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 $opt{unary_ops} ||= [];
165 # rudimentary sanity-check for user supplied bits treated as functions/operators
166 # If a purported function matches this regular expression, an exception is thrown.
167 # Literal SQL is *NOT* subject to this check, only functions (and column names
168 # when quoting is not in effect)
171 # need to guard against ()'s in column names too, but this will break tons of
172 # hacks... ideas anyone?
173 $opt{injection_guard} ||= qr/
179 return bless \%opt, $class;
182 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
183 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
185 sub _assert_pass_injection_guard {
186 if ($_[1] =~ $_[0]->{injection_guard}) {
187 my $class = ref $_[0];
188 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
189 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
190 . "{injection_guard} attribute to ${class}->new()"
195 #======================================================================
197 #======================================================================
201 my $table = $self->_table(shift);
202 my $data = shift || return;
205 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
206 my ($sql, @bind) = $self->$method($data);
207 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
209 if ($options->{returning}) {
210 my ($s, @b) = $self->_insert_returning($options);
215 return wantarray ? ($sql, @bind) : $sql;
218 # So that subclasses can override INSERT ... RETURNING separately from
219 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
220 sub _insert_returning { shift->_returning(@_) }
223 my ($self, $options) = @_;
225 my $f = $options->{returning};
227 my ($sql, @bind) = $self->_render_expr(
228 $self->_expand_maybe_list_expr($f, undef, -ident)
231 ? $self->_sqlcase(' returning ') . $sql
232 : ($self->_sqlcase(' returning ').$sql, @bind);
235 sub _insert_HASHREF { # explicit list of fields and then values
236 my ($self, $data) = @_;
238 my @fields = sort keys %$data;
240 my ($sql, @bind) = $self->_insert_values($data);
243 $_ = $self->_quote($_) foreach @fields;
244 $sql = "( ".join(", ", @fields).") ".$sql;
246 return ($sql, @bind);
249 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
250 my ($self, $data) = @_;
252 # no names (arrayref) so can't generate bindtype
253 $self->{bindtype} ne 'columns'
254 or belch "can't do 'columns' bindtype when called with arrayref";
256 my (@values, @all_bind);
257 foreach my $value (@$data) {
258 my ($values, @bind) = $self->_insert_value(undef, $value);
259 push @values, $values;
260 push @all_bind, @bind;
262 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
263 return ($sql, @all_bind);
266 sub _insert_ARRAYREFREF { # literal SQL with bind
267 my ($self, $data) = @_;
269 my ($sql, @bind) = @${$data};
270 $self->_assert_bindval_matches_bindtype(@bind);
272 return ($sql, @bind);
276 sub _insert_SCALARREF { # literal SQL without bind
277 my ($self, $data) = @_;
283 my ($self, $data) = @_;
285 my (@values, @all_bind);
286 foreach my $column (sort keys %$data) {
287 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
288 push @values, $values;
289 push @all_bind, @bind;
291 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
292 return ($sql, @all_bind);
296 my ($self, $column, $v) = @_;
298 return $self->_render_expr(
299 $self->_expand_insert_value($column, $v)
303 sub _expand_insert_value {
304 my ($self, $column, $v) = @_;
306 if (ref($v) eq 'ARRAY') {
307 if ($self->{array_datatypes}) {
308 return +{ -bind => [ $column, $v ] };
310 my ($sql, @bind) = @$v;
311 $self->_assert_bindval_matches_bindtype(@bind);
312 return +{ -literal => $v };
314 if (ref($v) eq 'HASH') {
315 if (grep !/^-/, keys %$v) {
316 belch "HASH ref as bind value in insert is not supported";
317 return +{ -bind => [ $column, $v ] };
321 return +{ -bind => [ $column, undef ] };
323 local our $Cur_Col_Meta = $column;
324 return $self->_expand_expr($v);
329 #======================================================================
331 #======================================================================
336 my $table = $self->_table(shift);
337 my $data = shift || return;
341 # first build the 'SET' part of the sql statement
342 puke "Unsupported data type specified to \$sql->update"
343 unless ref $data eq 'HASH';
345 my ($sql, @all_bind) = $self->_update_set_values($data);
346 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
350 my($where_sql, @where_bind) = $self->where($where);
352 push @all_bind, @where_bind;
355 if ($options->{returning}) {
356 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
357 $sql .= $returning_sql;
358 push @all_bind, @returning_bind;
361 return wantarray ? ($sql, @all_bind) : $sql;
364 sub _update_set_values {
365 my ($self, $data) = @_;
367 return $self->_render_expr(
368 $self->_expand_update_set_values($data),
372 sub _expand_update_set_values {
373 my ($self, $data) = @_;
374 $self->_expand_maybe_list_expr( [
377 +{ -op => [ '=', { -ident => $k }, $set ] };
383 ? ($self->{array_datatypes}
384 ? [ $k, +{ -bind => [ $k, $v ] } ]
385 : [ $k, +{ -literal => $v } ])
387 local our $Cur_Col_Meta = $k;
388 [ $k, $self->_expand_expr($v) ]
395 # So that subclasses can override UPDATE ... RETURNING separately from
397 sub _update_returning { shift->_returning(@_) }
401 #======================================================================
403 #======================================================================
408 my $table = $self->_table(shift);
409 my $fields = shift || '*';
413 my ($fields_sql, @bind) = $self->_select_fields($fields);
415 my ($where_sql, @where_bind) = $self->where($where, $order);
416 push @bind, @where_bind;
418 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
419 $self->_sqlcase('from'), $table)
422 return wantarray ? ($sql, @bind) : $sql;
426 my ($self, $fields) = @_;
427 return $self->_render_expr(
428 $self->_expand_maybe_list_expr($fields, undef, '-ident')
432 #======================================================================
434 #======================================================================
439 my $table = $self->_table(shift);
443 my($where_sql, @bind) = $self->where($where);
444 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
446 if ($options->{returning}) {
447 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
448 $sql .= $returning_sql;
449 push @bind, @returning_bind;
452 return wantarray ? ($sql, @bind) : $sql;
455 # So that subclasses can override DELETE ... RETURNING separately from
457 sub _delete_returning { shift->_returning(@_) }
461 #======================================================================
463 #======================================================================
467 # Finally, a separate routine just to handle WHERE clauses
469 my ($self, $where, $order) = @_;
471 local $self->{convert_where} = $self->{convert};
474 my ($sql, @bind) = defined($where)
475 ? $self->_recurse_where($where)
477 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
481 my ($order_sql, @order_bind) = $self->_order_by($order);
483 push @bind, @order_bind;
486 return wantarray ? ($sql, @bind) : $sql;
490 my ($self, $expr, $logic, $default_scalar_to) = @_;
491 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
492 return undef unless defined($expr);
493 if (ref($expr) eq 'HASH') {
494 if (keys %$expr > 1) {
498 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
502 return unless %$expr;
503 return $self->_expand_expr_hashpair(%$expr, $logic);
505 if (ref($expr) eq 'ARRAY') {
506 my $logic = lc($logic || $self->{logic});
507 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
513 while (my ($el) = splice @expr, 0, 1) {
514 puke "Supplying an empty left hand side argument is not supported in array-pairs"
515 unless defined($el) and length($el);
516 my $elref = ref($el);
518 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
519 } elsif ($elref eq 'ARRAY') {
520 push(@res, $self->_expand_expr($el)) if @$el;
521 } elsif (my $l = is_literal_value($el)) {
522 push @res, { -literal => $l };
523 } elsif ($elref eq 'HASH') {
524 push @res, $self->_expand_expr($el);
529 return { -op => [ $logic, @res ] };
531 if (my $literal = is_literal_value($expr)) {
532 return +{ -literal => $literal };
534 if (!ref($expr) or Scalar::Util::blessed($expr)) {
535 if (my $d = $Default_Scalar_To) {
536 return +{ $d => $expr };
538 if (my $m = our $Cur_Col_Meta) {
539 return +{ -bind => [ $m, $expr ] };
541 return +{ -value => $expr };
546 sub _expand_expr_hashpair {
547 my ($self, $k, $v, $logic) = @_;
548 unless (defined($k) and length($k)) {
549 if (defined($k) and my $literal = is_literal_value($v)) {
550 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
551 return { -literal => $literal };
553 puke "Supplying an empty left hand side argument is not supported";
556 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
557 if ($k =~ s/ [_\s]? \d+ $//x ) {
558 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
559 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
562 return $self->_expand_expr($v);
566 return $self->_expand_expr($v);
568 puke "-bool => undef not supported" unless defined($v);
569 return { -ident => $v };
572 return { -op => [ 'not', $self->_expand_expr($v) ] };
574 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
577 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
580 if (my ($logic) = $k =~ /^-(and|or)$/i) {
581 if (ref($v) eq 'HASH') {
582 return $self->_expand_expr($v, $logic);
584 if (ref($v) eq 'ARRAY') {
585 return $self->_expand_expr($v, $logic);
590 $op =~ s/^-// if length($op) > 1;
592 # top level special ops are illegal in general
593 puke "Illegal use of top-level '-$op'"
594 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
596 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
597 return +{ -bind => [ $m, $v ] };
599 if ($k eq '-op' or $k eq '-ident' or $k eq '-value' or $k eq '-bind' or $k eq '-literal' or $k eq '-func') {
602 if (my $custom = $self->{custom_expansions}{($k =~ /^-(.*)$/)[0]}) {
603 return $self->$custom($v);
608 and (keys %$v)[0] =~ /^-/
610 my ($func) = $k =~ /^-(.*)$/;
611 return +{ -func => [ $func, $self->_expand_expr($v) ] };
613 if (!ref($v) or is_literal_value($v)) {
614 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
621 and exists $v->{-value}
622 and not defined $v->{-value}
625 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
627 if (!ref($v) or Scalar::Util::blessed($v)) {
632 { -bind => [ $k, $v ] }
636 if (ref($v) eq 'HASH') {
640 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
647 $self->_assert_pass_injection_guard($vk);
648 if ($vk =~ s/ [_\s]? \d+ $//x ) {
649 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
650 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
652 if ($vk =~ /^(?:not[ _])?between$/) {
653 local our $Cur_Col_Meta = $k;
654 my @rhs = map $self->_expand_expr($_),
655 ref($vv) eq 'ARRAY' ? @$vv : $vv;
657 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
659 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
661 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
664 join(' ', split '_', $vk),
669 if ($vk =~ /^(?:not[ _])?in$/) {
670 if (my $literal = is_literal_value($vv)) {
671 my ($sql, @bind) = @$literal;
672 my $opened_sql = $self->_open_outer_paren($sql);
674 $vk, { -ident => $k },
675 [ { -literal => [ $opened_sql, @bind ] } ]
679 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
680 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
681 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
682 . 'will emit the logically correct SQL instead of raising this exception)'
684 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
686 my @rhs = map $self->_expand_expr($_),
687 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
688 map { defined($_) ? $_: puke($undef_err) }
689 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
690 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
693 join(' ', split '_', $vk),
698 if ($vk eq 'ident') {
699 if (! defined $vv or ref $vv) {
700 puke "-$vk requires a single plain scalar argument (a quotable identifier)";
708 if ($vk eq 'value') {
709 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
713 { -bind => [ $k, $vv ] }
716 if ($vk =~ /^is(?:[ _]not)?$/) {
717 puke "$vk can only take undef as argument"
721 and exists($vv->{-value})
722 and !defined($vv->{-value})
725 return +{ -op => [ $vk.' null', { -ident => $k } ] };
727 if ($vk =~ /^(and|or)$/) {
728 if (ref($vv) eq 'HASH') {
731 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
736 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{user_special_ops}}) {
737 return { -op => [ $vk, { -ident => $k }, $vv ] };
739 if (ref($vv) eq 'ARRAY') {
740 my ($logic, @values) = (
741 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
746 $vk =~ $self->{inequality_op}
747 or join(' ', split '_', $vk) =~ $self->{not_like_op}
749 if (lc($logic) eq '-or' and @values > 1) {
750 my $op = uc join ' ', split '_', $vk;
751 belch "A multi-element arrayref as an argument to the inequality op '$op' "
752 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
753 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
758 # try to DWIM on equality operators
759 my $op = join ' ', split '_', $vk;
761 $op =~ $self->{equality_op} ? $self->sqlfalse
762 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
763 : $op =~ $self->{inequality_op} ? $self->sqltrue
764 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
765 : puke "operator '$op' applied on an empty array (field '$k')";
769 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
777 and exists $vv->{-value}
778 and not defined $vv->{-value}
781 my $op = join ' ', split '_', $vk;
783 $op =~ /^not$/i ? 'is not' # legacy
784 : $op =~ $self->{equality_op} ? 'is'
785 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
786 : $op =~ $self->{inequality_op} ? 'is not'
787 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
788 : puke "unexpected operator '$op' with undef operand";
789 return +{ -op => [ $is.' null', { -ident => $k } ] };
791 local our $Cur_Col_Meta = $k;
795 $self->_expand_expr($vv)
798 if (ref($v) eq 'ARRAY') {
799 return $self->sqlfalse unless @$v;
800 $self->_debug("ARRAY($k) means distribute over elements");
802 $v->[0] =~ /^-((?:and|or))$/i
803 ? ($v = [ @{$v}[1..$#$v] ], $1)
804 : ($self->{logic} || 'or')
808 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
811 if (my $literal = is_literal_value($v)) {
813 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
816 my ($sql, @bind) = @$literal;
817 if ($self->{bindtype} eq 'columns') {
819 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
820 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
824 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
830 my ($self, $expr) = @_;
831 my ($k, $v, @rest) = %$expr;
833 my %op = map +("-$_" => '_render_'.$_),
834 qw(op func value bind ident literal);
835 if (my $meth = $op{$k}) {
836 return $self->$meth($v);
838 die "notreached: $k";
842 my ($self, $where, $logic) = @_;
844 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
846 my $where_exp = $self->_expand_expr($where, $logic);
848 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
850 # dispatch on appropriate method according to refkind of $where
851 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
853 # my ($sql, @bind) = $self->$method($where_exp, $logic);
855 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
857 # DBIx::Class used to call _recurse_where in scalar context
858 # something else might too...
860 return ($sql, @bind);
863 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
869 my ($self, $ident) = @_;
871 return $self->_convert($self->_quote($ident));
875 my ($self, $value) = @_;
877 return ($self->_convert('?'), $self->_bindtype(undef, $value));
880 my %unop_postfix = map +($_ => 1),
881 'is null', 'is not null',
889 my ($self, $args) = @_;
890 my ($left, $low, $high) = @$args;
891 my ($rhsql, @rhbind) = do {
893 puke "Single arg to between must be a literal"
894 unless $low->{-literal};
897 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
898 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
899 @{$l}[1..$#$l], @{$h}[1..$#$h])
902 my ($lhsql, @lhbind) = $self->_render_expr($left);
904 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
908 }), 'between', 'not between'),
912 my ($self, $args) = @_;
913 my ($lhs, $rhs) = @$args;
916 my ($sql, @bind) = $self->_render_expr($_);
917 push @in_bind, @bind;
920 my ($lhsql, @lbind) = $self->_render_expr($lhs);
922 $lhsql.' '.$self->_sqlcase($op).' ( '
933 my ($op, @args) = @$v;
934 $op =~ s/^-// if length($op) > 1;
936 if (my $h = $special{$op}) {
937 return $self->$h(\@args);
939 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{user_special_ops}}) {
940 puke "Special op '${op}' requires first value to be identifier"
941 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
942 return $self->${\($us->{handler})}($k, $op, $args[1]);
944 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
945 if (@args == 1 and $op !~ /^(and|or)$/) {
946 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
947 my $op_sql = $self->_sqlcase($final_op);
949 $unop_postfix{lc($final_op)}
950 ? "${expr_sql} ${op_sql}"
951 : "${op_sql} ${expr_sql}"
953 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
955 my @parts = map [ $self->_render_expr($_) ], @args;
956 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
957 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
962 map @{$_}[1..$#$_], @parts
969 my ($self, $rest) = @_;
970 my ($func, @args) = @$rest;
974 push @arg_sql, shift @x;
976 } map [ $self->_render_expr($_) ], @args;
977 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
981 my ($self, $bind) = @_;
982 return ($self->_convert('?'), $self->_bindtype(@$bind));
985 sub _render_literal {
986 my ($self, $literal) = @_;
987 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
991 # Some databases (SQLite) treat col IN (1, 2) different from
992 # col IN ( (1, 2) ). Use this to strip all outer parens while
993 # adding them back in the corresponding method
994 sub _open_outer_paren {
995 my ($self, $sql) = @_;
997 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
999 # there are closing parens inside, need the heavy duty machinery
1000 # to reevaluate the extraction starting from $sql (full reevaluation)
1001 if ($inner =~ /\)/) {
1002 require Text::Balanced;
1004 my (undef, $remainder) = do {
1005 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1007 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1010 # the entire expression needs to be a balanced bracketed thing
1011 # (after an extract no remainder sans trailing space)
1012 last if defined $remainder and $remainder =~ /\S/;
1022 #======================================================================
1024 #======================================================================
1027 my ($self, $arg) = @_;
1029 return '' unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1031 my $expander = sub {
1032 my ($self, $dir, $expr) = @_;
1033 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1034 map $self->_expand_expr($_, undef, -ident),
1035 ref($expr) eq 'ARRAY' ? @$expr : $expr;
1036 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1039 local $self->{custom_expansions} = {
1040 asc => sub { shift->$expander(asc => @_) },
1041 desc => sub { shift->$expander(desc => @_) },
1044 my $expanded = $self->$expander(undef, $arg);
1046 my ($sql, @bind) = $self->_render_expr($expanded);
1048 my $final_sql = $self->_sqlcase(' order by ').$sql;
1050 return wantarray ? ($final_sql, @bind) : $final_sql;
1053 #======================================================================
1054 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1055 #======================================================================
1060 ($self->_render_expr(
1061 $self->_expand_maybe_list_expr($from, undef, -ident)
1066 #======================================================================
1068 #======================================================================
1070 sub _expand_maybe_list_expr {
1071 my ($self, $expr, $logic, $default) = @_;
1073 if (ref($expr) eq 'ARRAY') {
1075 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1082 return $self->_expand_expr($e, $logic, $default);
1085 # highly optimized, as it's called way too often
1087 # my ($self, $label) = @_;
1089 return '' unless defined $_[1];
1090 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1092 $_[0]->{quote_char} or
1093 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1095 my $qref = ref $_[0]->{quote_char};
1097 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1098 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1099 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1101 my $esc = $_[0]->{escape_char} || $r;
1103 # parts containing * are naturally unquoted
1104 return join($_[0]->{name_sep}||'', map
1105 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1106 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1111 # Conversion, if applicable
1113 #my ($self, $arg) = @_;
1114 if ($_[0]->{convert_where}) {
1115 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1122 #my ($self, $col, @vals) = @_;
1123 # called often - tighten code
1124 return $_[0]->{bindtype} eq 'columns'
1125 ? map {[$_[1], $_]} @_[2 .. $#_]
1130 # Dies if any element of @bind is not in [colname => value] format
1131 # if bindtype is 'columns'.
1132 sub _assert_bindval_matches_bindtype {
1133 # my ($self, @bind) = @_;
1135 if ($self->{bindtype} eq 'columns') {
1137 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1138 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1144 sub _join_sql_clauses {
1145 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1147 if (@$clauses_aref > 1) {
1148 my $join = " " . $self->_sqlcase($logic) . " ";
1149 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1150 return ($sql, @$bind_aref);
1152 elsif (@$clauses_aref) {
1153 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1156 return (); # if no SQL, ignore @$bind_aref
1161 # Fix SQL case, if so requested
1163 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1164 # don't touch the argument ... crooked logic, but let's not change it!
1165 return $_[0]->{case} ? $_[1] : uc($_[1]);
1169 #======================================================================
1170 # DISPATCHING FROM REFKIND
1171 #======================================================================
1174 my ($self, $data) = @_;
1176 return 'UNDEF' unless defined $data;
1178 # blessed objects are treated like scalars
1179 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1181 return 'SCALAR' unless $ref;
1184 while ($ref eq 'REF') {
1186 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1190 return ($ref||'SCALAR') . ('REF' x $n_steps);
1194 my ($self, $data) = @_;
1195 my @try = ($self->_refkind($data));
1196 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1197 push @try, 'FALLBACK';
1201 sub _METHOD_FOR_refkind {
1202 my ($self, $meth_prefix, $data) = @_;
1205 for (@{$self->_try_refkind($data)}) {
1206 $method = $self->can($meth_prefix."_".$_)
1210 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1214 sub _SWITCH_refkind {
1215 my ($self, $data, $dispatch_table) = @_;
1218 for (@{$self->_try_refkind($data)}) {
1219 $coderef = $dispatch_table->{$_}
1223 puke "no dispatch entry for ".$self->_refkind($data)
1232 #======================================================================
1233 # VALUES, GENERATE, AUTOLOAD
1234 #======================================================================
1236 # LDNOTE: original code from nwiger, didn't touch code in that section
1237 # I feel the AUTOLOAD stuff should not be the default, it should
1238 # only be activated on explicit demand by user.
1242 my $data = shift || return;
1243 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1244 unless ref $data eq 'HASH';
1247 foreach my $k (sort keys %$data) {
1248 my $v = $data->{$k};
1249 $self->_SWITCH_refkind($v, {
1251 if ($self->{array_datatypes}) { # array datatype
1252 push @all_bind, $self->_bindtype($k, $v);
1254 else { # literal SQL with bind
1255 my ($sql, @bind) = @$v;
1256 $self->_assert_bindval_matches_bindtype(@bind);
1257 push @all_bind, @bind;
1260 ARRAYREFREF => sub { # literal SQL with bind
1261 my ($sql, @bind) = @${$v};
1262 $self->_assert_bindval_matches_bindtype(@bind);
1263 push @all_bind, @bind;
1265 SCALARREF => sub { # literal SQL without bind
1267 SCALAR_or_UNDEF => sub {
1268 push @all_bind, $self->_bindtype($k, $v);
1279 my(@sql, @sqlq, @sqlv);
1283 if ($ref eq 'HASH') {
1284 for my $k (sort keys %$_) {
1287 my $label = $self->_quote($k);
1288 if ($r eq 'ARRAY') {
1289 # literal SQL with bind
1290 my ($sql, @bind) = @$v;
1291 $self->_assert_bindval_matches_bindtype(@bind);
1292 push @sqlq, "$label = $sql";
1294 } elsif ($r eq 'SCALAR') {
1295 # literal SQL without bind
1296 push @sqlq, "$label = $$v";
1298 push @sqlq, "$label = ?";
1299 push @sqlv, $self->_bindtype($k, $v);
1302 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1303 } elsif ($ref eq 'ARRAY') {
1304 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1307 if ($r eq 'ARRAY') { # literal SQL with bind
1308 my ($sql, @bind) = @$v;
1309 $self->_assert_bindval_matches_bindtype(@bind);
1312 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1313 # embedded literal SQL
1320 push @sql, '(' . join(', ', @sqlq) . ')';
1321 } elsif ($ref eq 'SCALAR') {
1325 # strings get case twiddled
1326 push @sql, $self->_sqlcase($_);
1330 my $sql = join ' ', @sql;
1332 # this is pretty tricky
1333 # if ask for an array, return ($stmt, @bind)
1334 # otherwise, s/?/shift @sqlv/ to put it inline
1336 return ($sql, @sqlv);
1338 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1339 ref $d ? $d->[1] : $d/e;
1348 # This allows us to check for a local, then _form, attr
1350 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1351 return $self->generate($name, @_);
1362 SQL::Abstract - Generate SQL from Perl data structures
1368 my $sql = SQL::Abstract->new;
1370 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1372 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1374 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1376 my($stmt, @bind) = $sql->delete($table, \%where);
1378 # Then, use these in your DBI statements
1379 my $sth = $dbh->prepare($stmt);
1380 $sth->execute(@bind);
1382 # Just generate the WHERE clause
1383 my($stmt, @bind) = $sql->where(\%where, $order);
1385 # Return values in the same order, for hashed queries
1386 # See PERFORMANCE section for more details
1387 my @bind = $sql->values(\%fieldvals);
1391 This module was inspired by the excellent L<DBIx::Abstract>.
1392 However, in using that module I found that what I really wanted
1393 to do was generate SQL, but still retain complete control over my
1394 statement handles and use the DBI interface. So, I set out to
1395 create an abstract SQL generation module.
1397 While based on the concepts used by L<DBIx::Abstract>, there are
1398 several important differences, especially when it comes to WHERE
1399 clauses. I have modified the concepts used to make the SQL easier
1400 to generate from Perl data structures and, IMO, more intuitive.
1401 The underlying idea is for this module to do what you mean, based
1402 on the data structures you provide it. The big advantage is that
1403 you don't have to modify your code every time your data changes,
1404 as this module figures it out.
1406 To begin with, an SQL INSERT is as easy as just specifying a hash
1407 of C<key=value> pairs:
1410 name => 'Jimbo Bobson',
1411 phone => '123-456-7890',
1412 address => '42 Sister Lane',
1413 city => 'St. Louis',
1414 state => 'Louisiana',
1417 The SQL can then be generated with this:
1419 my($stmt, @bind) = $sql->insert('people', \%data);
1421 Which would give you something like this:
1423 $stmt = "INSERT INTO people
1424 (address, city, name, phone, state)
1425 VALUES (?, ?, ?, ?, ?)";
1426 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1427 '123-456-7890', 'Louisiana');
1429 These are then used directly in your DBI code:
1431 my $sth = $dbh->prepare($stmt);
1432 $sth->execute(@bind);
1434 =head2 Inserting and Updating Arrays
1436 If your database has array types (like for example Postgres),
1437 activate the special option C<< array_datatypes => 1 >>
1438 when creating the C<SQL::Abstract> object.
1439 Then you may use an arrayref to insert and update database array types:
1441 my $sql = SQL::Abstract->new(array_datatypes => 1);
1443 planets => [qw/Mercury Venus Earth Mars/]
1446 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1450 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1452 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1455 =head2 Inserting and Updating SQL
1457 In order to apply SQL functions to elements of your C<%data> you may
1458 specify a reference to an arrayref for the given hash value. For example,
1459 if you need to execute the Oracle C<to_date> function on a value, you can
1460 say something like this:
1464 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1467 The first value in the array is the actual SQL. Any other values are
1468 optional and would be included in the bind values array. This gives
1471 my($stmt, @bind) = $sql->insert('people', \%data);
1473 $stmt = "INSERT INTO people (name, date_entered)
1474 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1475 @bind = ('Bill', '03/02/2003');
1477 An UPDATE is just as easy, all you change is the name of the function:
1479 my($stmt, @bind) = $sql->update('people', \%data);
1481 Notice that your C<%data> isn't touched; the module will generate
1482 the appropriately quirky SQL for you automatically. Usually you'll
1483 want to specify a WHERE clause for your UPDATE, though, which is
1484 where handling C<%where> hashes comes in handy...
1486 =head2 Complex where statements
1488 This module can generate pretty complicated WHERE statements
1489 easily. For example, simple C<key=value> pairs are taken to mean
1490 equality, and if you want to see if a field is within a set
1491 of values, you can use an arrayref. Let's say we wanted to
1492 SELECT some data based on this criteria:
1495 requestor => 'inna',
1496 worker => ['nwiger', 'rcwe', 'sfz'],
1497 status => { '!=', 'completed' }
1500 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1502 The above would give you something like this:
1504 $stmt = "SELECT * FROM tickets WHERE
1505 ( requestor = ? ) AND ( status != ? )
1506 AND ( worker = ? OR worker = ? OR worker = ? )";
1507 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1509 Which you could then use in DBI code like so:
1511 my $sth = $dbh->prepare($stmt);
1512 $sth->execute(@bind);
1518 The methods are simple. There's one for every major SQL operation,
1519 and a constructor you use first. The arguments are specified in a
1520 similar order for each method (table, then fields, then a where
1521 clause) to try and simplify things.
1523 =head2 new(option => 'value')
1525 The C<new()> function takes a list of options and values, and returns
1526 a new B<SQL::Abstract> object which can then be used to generate SQL
1527 through the methods below. The options accepted are:
1533 If set to 'lower', then SQL will be generated in all lowercase. By
1534 default SQL is generated in "textbook" case meaning something like:
1536 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1538 Any setting other than 'lower' is ignored.
1542 This determines what the default comparison operator is. By default
1543 it is C<=>, meaning that a hash like this:
1545 %where = (name => 'nwiger', email => 'nate@wiger.org');
1547 Will generate SQL like this:
1549 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1551 However, you may want loose comparisons by default, so if you set
1552 C<cmp> to C<like> you would get SQL such as:
1554 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1556 You can also override the comparison on an individual basis - see
1557 the huge section on L</"WHERE CLAUSES"> at the bottom.
1559 =item sqltrue, sqlfalse
1561 Expressions for inserting boolean values within SQL statements.
1562 By default these are C<1=1> and C<1=0>. They are used
1563 by the special operators C<-in> and C<-not_in> for generating
1564 correct SQL even when the argument is an empty array (see below).
1568 This determines the default logical operator for multiple WHERE
1569 statements in arrays or hashes. If absent, the default logic is "or"
1570 for arrays, and "and" for hashes. This means that a WHERE
1574 event_date => {'>=', '2/13/99'},
1575 event_date => {'<=', '4/24/03'},
1578 will generate SQL like this:
1580 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1582 This is probably not what you want given this query, though (look
1583 at the dates). To change the "OR" to an "AND", simply specify:
1585 my $sql = SQL::Abstract->new(logic => 'and');
1587 Which will change the above C<WHERE> to:
1589 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1591 The logic can also be changed locally by inserting
1592 a modifier in front of an arrayref:
1594 @where = (-and => [event_date => {'>=', '2/13/99'},
1595 event_date => {'<=', '4/24/03'} ]);
1597 See the L</"WHERE CLAUSES"> section for explanations.
1601 This will automatically convert comparisons using the specified SQL
1602 function for both column and value. This is mostly used with an argument
1603 of C<upper> or C<lower>, so that the SQL will have the effect of
1604 case-insensitive "searches". For example, this:
1606 $sql = SQL::Abstract->new(convert => 'upper');
1607 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1609 Will turn out the following SQL:
1611 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1613 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1614 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1615 not validate this option; it will just pass through what you specify verbatim).
1619 This is a kludge because many databases suck. For example, you can't
1620 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1621 Instead, you have to use C<bind_param()>:
1623 $sth->bind_param(1, 'reg data');
1624 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1626 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1627 which loses track of which field each slot refers to. Fear not.
1629 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1630 Currently, you can specify either C<normal> (default) or C<columns>. If you
1631 specify C<columns>, you will get an array that looks like this:
1633 my $sql = SQL::Abstract->new(bindtype => 'columns');
1634 my($stmt, @bind) = $sql->insert(...);
1637 [ 'column1', 'value1' ],
1638 [ 'column2', 'value2' ],
1639 [ 'column3', 'value3' ],
1642 You can then iterate through this manually, using DBI's C<bind_param()>.
1644 $sth->prepare($stmt);
1647 my($col, $data) = @$_;
1648 if ($col eq 'details' || $col eq 'comments') {
1649 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1650 } elsif ($col eq 'image') {
1651 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1653 $sth->bind_param($i, $data);
1657 $sth->execute; # execute without @bind now
1659 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1660 Basically, the advantage is still that you don't have to care which fields
1661 are or are not included. You could wrap that above C<for> loop in a simple
1662 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1663 get a layer of abstraction over manual SQL specification.
1665 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1666 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1667 will expect the bind values in this format.
1671 This is the character that a table or column name will be quoted
1672 with. By default this is an empty string, but you could set it to
1673 the character C<`>, to generate SQL like this:
1675 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1677 Alternatively, you can supply an array ref of two items, the first being the left
1678 hand quote character, and the second the right hand quote character. For
1679 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1680 that generates SQL like this:
1682 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1684 Quoting is useful if you have tables or columns names that are reserved
1685 words in your database's SQL dialect.
1689 This is the character that will be used to escape L</quote_char>s appearing
1690 in an identifier before it has been quoted.
1692 The parameter default in case of a single L</quote_char> character is the quote
1695 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1696 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1697 of the B<opening (left)> L</quote_char> within the identifier are currently left
1698 untouched. The default for opening-closing-style quotes may change in future
1699 versions, thus you are B<strongly encouraged> to specify the escape character
1704 This is the character that separates a table and column name. It is
1705 necessary to specify this when the C<quote_char> option is selected,
1706 so that tables and column names can be individually quoted like this:
1708 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1710 =item injection_guard
1712 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1713 column name specified in a query structure. This is a safety mechanism to avoid
1714 injection attacks when mishandling user input e.g.:
1716 my %condition_as_column_value_pairs = get_values_from_user();
1717 $sqla->select( ... , \%condition_as_column_value_pairs );
1719 If the expression matches an exception is thrown. Note that literal SQL
1720 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1722 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1724 =item array_datatypes
1726 When this option is true, arrayrefs in INSERT or UPDATE are
1727 interpreted as array datatypes and are passed directly
1729 When this option is false, arrayrefs are interpreted
1730 as literal SQL, just like refs to arrayrefs
1731 (but this behavior is for backwards compatibility; when writing
1732 new queries, use the "reference to arrayref" syntax
1738 Takes a reference to a list of "special operators"
1739 to extend the syntax understood by L<SQL::Abstract>.
1740 See section L</"SPECIAL OPERATORS"> for details.
1744 Takes a reference to a list of "unary operators"
1745 to extend the syntax understood by L<SQL::Abstract>.
1746 See section L</"UNARY OPERATORS"> for details.
1752 =head2 insert($table, \@values || \%fieldvals, \%options)
1754 This is the simplest function. You simply give it a table name
1755 and either an arrayref of values or hashref of field/value pairs.
1756 It returns an SQL INSERT statement and a list of bind values.
1757 See the sections on L</"Inserting and Updating Arrays"> and
1758 L</"Inserting and Updating SQL"> for information on how to insert
1759 with those data types.
1761 The optional C<\%options> hash reference may contain additional
1762 options to generate the insert SQL. Currently supported options
1769 Takes either a scalar of raw SQL fields, or an array reference of
1770 field names, and adds on an SQL C<RETURNING> statement at the end.
1771 This allows you to return data generated by the insert statement
1772 (such as row IDs) without performing another C<SELECT> statement.
1773 Note, however, this is not part of the SQL standard and may not
1774 be supported by all database engines.
1778 =head2 update($table, \%fieldvals, \%where, \%options)
1780 This takes a table, hashref of field/value pairs, and an optional
1781 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1783 See the sections on L</"Inserting and Updating Arrays"> and
1784 L</"Inserting and Updating SQL"> for information on how to insert
1785 with those data types.
1787 The optional C<\%options> hash reference may contain additional
1788 options to generate the update SQL. Currently supported options
1795 See the C<returning> option to
1796 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1800 =head2 select($source, $fields, $where, $order)
1802 This returns a SQL SELECT statement and associated list of bind values, as
1803 specified by the arguments:
1809 Specification of the 'FROM' part of the statement.
1810 The argument can be either a plain scalar (interpreted as a table
1811 name, will be quoted), or an arrayref (interpreted as a list
1812 of table names, joined by commas, quoted), or a scalarref
1813 (literal SQL, not quoted).
1817 Specification of the list of fields to retrieve from
1819 The argument can be either an arrayref (interpreted as a list
1820 of field names, will be joined by commas and quoted), or a
1821 plain scalar (literal SQL, not quoted).
1822 Please observe that this API is not as flexible as that of
1823 the first argument C<$source>, for backwards compatibility reasons.
1827 Optional argument to specify the WHERE part of the query.
1828 The argument is most often a hashref, but can also be
1829 an arrayref or plain scalar --
1830 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1834 Optional argument to specify the ORDER BY part of the query.
1835 The argument can be a scalar, a hashref or an arrayref
1836 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1842 =head2 delete($table, \%where, \%options)
1844 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1845 It returns an SQL DELETE statement and list of bind values.
1847 The optional C<\%options> hash reference may contain additional
1848 options to generate the delete SQL. Currently supported options
1855 See the C<returning> option to
1856 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1860 =head2 where(\%where, $order)
1862 This is used to generate just the WHERE clause. For example,
1863 if you have an arbitrary data structure and know what the
1864 rest of your SQL is going to look like, but want an easy way
1865 to produce a WHERE clause, use this. It returns an SQL WHERE
1866 clause and list of bind values.
1869 =head2 values(\%data)
1871 This just returns the values from the hash C<%data>, in the same
1872 order that would be returned from any of the other above queries.
1873 Using this allows you to markedly speed up your queries if you
1874 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1876 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1878 Warning: This is an experimental method and subject to change.
1880 This returns arbitrarily generated SQL. It's a really basic shortcut.
1881 It will return two different things, depending on return context:
1883 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1884 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1886 These would return the following:
1888 # First calling form
1889 $stmt = "CREATE TABLE test (?, ?)";
1890 @bind = (field1, field2);
1892 # Second calling form
1893 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1895 Depending on what you're trying to do, it's up to you to choose the correct
1896 format. In this example, the second form is what you would want.
1900 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1904 ALTER SESSION SET nls_date_format = 'MM/YY'
1906 You get the idea. Strings get their case twiddled, but everything
1907 else remains verbatim.
1909 =head1 EXPORTABLE FUNCTIONS
1911 =head2 is_plain_value
1913 Determines if the supplied argument is a plain value as understood by this
1918 =item * The value is C<undef>
1920 =item * The value is a non-reference
1922 =item * The value is an object with stringification overloading
1924 =item * The value is of the form C<< { -value => $anything } >>
1928 On failure returns C<undef>, on success returns a B<scalar> reference
1929 to the original supplied argument.
1935 The stringification overloading detection is rather advanced: it takes
1936 into consideration not only the presence of a C<""> overload, but if that
1937 fails also checks for enabled
1938 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1939 on either C<0+> or C<bool>.
1941 Unfortunately testing in the field indicates that this
1942 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1943 but only when very large numbers of stringifying objects are involved.
1944 At the time of writing ( Sep 2014 ) there is no clear explanation of
1945 the direct cause, nor is there a manageably small test case that reliably
1946 reproduces the problem.
1948 If you encounter any of the following exceptions in B<random places within
1949 your application stack> - this module may be to blame:
1951 Operation "ne": no method found,
1952 left argument in overloaded package <something>,
1953 right argument in overloaded package <something>
1957 Stub found while resolving method "???" overloading """" in package <something>
1959 If you fall victim to the above - please attempt to reduce the problem
1960 to something that could be sent to the L<SQL::Abstract developers
1961 |DBIx::Class/GETTING HELP/SUPPORT>
1962 (either publicly or privately). As a workaround in the meantime you can
1963 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
1964 value, which will most likely eliminate your problem (at the expense of
1965 not being able to properly detect exotic forms of stringification).
1967 This notice and environment variable will be removed in a future version,
1968 as soon as the underlying problem is found and a reliable workaround is
1973 =head2 is_literal_value
1975 Determines if the supplied argument is a literal value as understood by this
1980 =item * C<\$sql_string>
1982 =item * C<\[ $sql_string, @bind_values ]>
1986 On failure returns C<undef>, on success returns an B<array> reference
1987 containing the unpacked version of the supplied literal SQL and bind values.
1989 =head1 WHERE CLAUSES
1993 This module uses a variation on the idea from L<DBIx::Abstract>. It
1994 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
1995 module is that things in arrays are OR'ed, and things in hashes
1998 The easiest way to explain is to show lots of examples. After
1999 each C<%where> hash shown, it is assumed you used:
2001 my($stmt, @bind) = $sql->where(\%where);
2003 However, note that the C<%where> hash can be used directly in any
2004 of the other functions as well, as described above.
2006 =head2 Key-value pairs
2008 So, let's get started. To begin, a simple hash:
2012 status => 'completed'
2015 Is converted to SQL C<key = val> statements:
2017 $stmt = "WHERE user = ? AND status = ?";
2018 @bind = ('nwiger', 'completed');
2020 One common thing I end up doing is having a list of values that
2021 a field can be in. To do this, simply specify a list inside of
2026 status => ['assigned', 'in-progress', 'pending'];
2029 This simple code will create the following:
2031 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2032 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2034 A field associated to an empty arrayref will be considered a
2035 logical false and will generate 0=1.
2037 =head2 Tests for NULL values
2039 If the value part is C<undef> then this is converted to SQL <IS NULL>
2048 $stmt = "WHERE user = ? AND status IS NULL";
2051 To test if a column IS NOT NULL:
2055 status => { '!=', undef },
2058 =head2 Specific comparison operators
2060 If you want to specify a different type of operator for your comparison,
2061 you can use a hashref for a given column:
2065 status => { '!=', 'completed' }
2068 Which would generate:
2070 $stmt = "WHERE user = ? AND status != ?";
2071 @bind = ('nwiger', 'completed');
2073 To test against multiple values, just enclose the values in an arrayref:
2075 status => { '=', ['assigned', 'in-progress', 'pending'] };
2077 Which would give you:
2079 "WHERE status = ? OR status = ? OR status = ?"
2082 The hashref can also contain multiple pairs, in which case it is expanded
2083 into an C<AND> of its elements:
2087 status => { '!=', 'completed', -not_like => 'pending%' }
2090 # Or more dynamically, like from a form
2091 $where{user} = 'nwiger';
2092 $where{status}{'!='} = 'completed';
2093 $where{status}{'-not_like'} = 'pending%';
2095 # Both generate this
2096 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2097 @bind = ('nwiger', 'completed', 'pending%');
2100 To get an OR instead, you can combine it with the arrayref idea:
2104 priority => [ { '=', 2 }, { '>', 5 } ]
2107 Which would generate:
2109 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2110 @bind = ('2', '5', 'nwiger');
2112 If you want to include literal SQL (with or without bind values), just use a
2113 scalar reference or reference to an arrayref as the value:
2116 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2117 date_expires => { '<' => \"now()" }
2120 Which would generate:
2122 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2123 @bind = ('11/26/2008');
2126 =head2 Logic and nesting operators
2128 In the example above,
2129 there is a subtle trap if you want to say something like
2130 this (notice the C<AND>):
2132 WHERE priority != ? AND priority != ?
2134 Because, in Perl you I<can't> do this:
2136 priority => { '!=' => 2, '!=' => 1 }
2138 As the second C<!=> key will obliterate the first. The solution
2139 is to use the special C<-modifier> form inside an arrayref:
2141 priority => [ -and => {'!=', 2},
2145 Normally, these would be joined by C<OR>, but the modifier tells it
2146 to use C<AND> instead. (Hint: You can use this in conjunction with the
2147 C<logic> option to C<new()> in order to change the way your queries
2148 work by default.) B<Important:> Note that the C<-modifier> goes
2149 B<INSIDE> the arrayref, as an extra first element. This will
2150 B<NOT> do what you think it might:
2152 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2154 Here is a quick list of equivalencies, since there is some overlap:
2157 status => {'!=', 'completed', 'not like', 'pending%' }
2158 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2161 status => {'=', ['assigned', 'in-progress']}
2162 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2163 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2167 =head2 Special operators: IN, BETWEEN, etc.
2169 You can also use the hashref format to compare a list of fields using the
2170 C<IN> comparison operator, by specifying the list as an arrayref:
2173 status => 'completed',
2174 reportid => { -in => [567, 2335, 2] }
2177 Which would generate:
2179 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2180 @bind = ('completed', '567', '2335', '2');
2182 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2185 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2186 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2187 'sqltrue' (by default: C<1=1>).
2189 In addition to the array you can supply a chunk of literal sql or
2190 literal sql with bind:
2193 customer => { -in => \[
2194 'SELECT cust_id FROM cust WHERE balance > ?',
2197 status => { -in => \'SELECT status_codes FROM states' },
2203 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2204 AND status IN ( SELECT status_codes FROM states )
2208 Finally, if the argument to C<-in> is not a reference, it will be
2209 treated as a single-element array.
2211 Another pair of operators is C<-between> and C<-not_between>,
2212 used with an arrayref of two values:
2216 completion_date => {
2217 -not_between => ['2002-10-01', '2003-02-06']
2223 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2225 Just like with C<-in> all plausible combinations of literal SQL
2229 start0 => { -between => [ 1, 2 ] },
2230 start1 => { -between => \["? AND ?", 1, 2] },
2231 start2 => { -between => \"lower(x) AND upper(y)" },
2232 start3 => { -between => [
2234 \["upper(?)", 'stuff' ],
2241 ( start0 BETWEEN ? AND ? )
2242 AND ( start1 BETWEEN ? AND ? )
2243 AND ( start2 BETWEEN lower(x) AND upper(y) )
2244 AND ( start3 BETWEEN lower(x) AND upper(?) )
2246 @bind = (1, 2, 1, 2, 'stuff');
2249 These are the two builtin "special operators"; but the
2250 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2252 =head2 Unary operators: bool
2254 If you wish to test against boolean columns or functions within your
2255 database you can use the C<-bool> and C<-not_bool> operators. For
2256 example to test the column C<is_user> being true and the column
2257 C<is_enabled> being false you would use:-
2261 -not_bool => 'is_enabled',
2266 WHERE is_user AND NOT is_enabled
2268 If a more complex combination is required, testing more conditions,
2269 then you should use the and/or operators:-
2274 -not_bool => { two=> { -rlike => 'bar' } },
2275 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2286 (NOT ( three = ? OR three > ? ))
2289 =head2 Nested conditions, -and/-or prefixes
2291 So far, we've seen how multiple conditions are joined with a top-level
2292 C<AND>. We can change this by putting the different conditions we want in
2293 hashes and then putting those hashes in an array. For example:
2298 status => { -like => ['pending%', 'dispatched'] },
2302 status => 'unassigned',
2306 This data structure would create the following:
2308 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2309 OR ( user = ? AND status = ? ) )";
2310 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2313 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2314 to change the logic inside:
2320 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2321 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2328 $stmt = "WHERE ( user = ?
2329 AND ( ( workhrs > ? AND geo = ? )
2330 OR ( workhrs < ? OR geo = ? ) ) )";
2331 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2333 =head3 Algebraic inconsistency, for historical reasons
2335 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2336 operator goes C<outside> of the nested structure; whereas when connecting
2337 several constraints on one column, the C<-and> operator goes
2338 C<inside> the arrayref. Here is an example combining both features:
2341 -and => [a => 1, b => 2],
2342 -or => [c => 3, d => 4],
2343 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2348 WHERE ( ( ( a = ? AND b = ? )
2349 OR ( c = ? OR d = ? )
2350 OR ( e LIKE ? AND e LIKE ? ) ) )
2352 This difference in syntax is unfortunate but must be preserved for
2353 historical reasons. So be careful: the two examples below would
2354 seem algebraically equivalent, but they are not
2357 { -like => 'foo%' },
2358 { -like => '%bar' },
2360 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2363 { col => { -like => 'foo%' } },
2364 { col => { -like => '%bar' } },
2366 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2369 =head2 Literal SQL and value type operators
2371 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2372 side" is a column name and the "right side" is a value (normally rendered as
2373 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2374 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2375 alter this behavior. There are several ways of doing so.
2379 This is a virtual operator that signals the string to its right side is an
2380 identifier (a column name) and not a value. For example to compare two
2381 columns you would write:
2384 priority => { '<', 2 },
2385 requestor => { -ident => 'submitter' },
2390 $stmt = "WHERE priority < ? AND requestor = submitter";
2393 If you are maintaining legacy code you may see a different construct as
2394 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2399 This is a virtual operator that signals that the construct to its right side
2400 is a value to be passed to DBI. This is for example necessary when you want
2401 to write a where clause against an array (for RDBMS that support such
2402 datatypes). For example:
2405 array => { -value => [1, 2, 3] }
2410 $stmt = 'WHERE array = ?';
2411 @bind = ([1, 2, 3]);
2413 Note that if you were to simply say:
2419 the result would probably not be what you wanted:
2421 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2426 Finally, sometimes only literal SQL will do. To include a random snippet
2427 of SQL verbatim, you specify it as a scalar reference. Consider this only
2428 as a last resort. Usually there is a better way. For example:
2431 priority => { '<', 2 },
2432 requestor => { -in => \'(SELECT name FROM hitmen)' },
2437 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2440 Note that in this example, you only get one bind parameter back, since
2441 the verbatim SQL is passed as part of the statement.
2445 Never use untrusted input as a literal SQL argument - this is a massive
2446 security risk (there is no way to check literal snippets for SQL
2447 injections and other nastyness). If you need to deal with untrusted input
2448 use literal SQL with placeholders as described next.
2450 =head3 Literal SQL with placeholders and bind values (subqueries)
2452 If the literal SQL to be inserted has placeholders and bind values,
2453 use a reference to an arrayref (yes this is a double reference --
2454 not so common, but perfectly legal Perl). For example, to find a date
2455 in Postgres you can use something like this:
2458 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2463 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2466 Note that you must pass the bind values in the same format as they are returned
2467 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2468 to C<columns>, you must provide the bind values in the
2469 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2470 scalar value; most commonly the column name, but you can use any scalar value
2471 (including references and blessed references), L<SQL::Abstract> will simply
2472 pass it through intact. So if C<bindtype> is set to C<columns> the above
2473 example will look like:
2476 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2479 Literal SQL is especially useful for nesting parenthesized clauses in the
2480 main SQL query. Here is a first example:
2482 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2486 bar => \["IN ($sub_stmt)" => @sub_bind],
2491 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2492 WHERE c2 < ? AND c3 LIKE ?))";
2493 @bind = (1234, 100, "foo%");
2495 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2496 are expressed in the same way. Of course the C<$sub_stmt> and
2497 its associated bind values can be generated through a former call
2500 my ($sub_stmt, @sub_bind)
2501 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2502 c3 => {-like => "foo%"}});
2505 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2508 In the examples above, the subquery was used as an operator on a column;
2509 but the same principle also applies for a clause within the main C<%where>
2510 hash, like an EXISTS subquery:
2512 my ($sub_stmt, @sub_bind)
2513 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2514 my %where = ( -and => [
2516 \["EXISTS ($sub_stmt)" => @sub_bind],
2521 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2522 WHERE c1 = ? AND c2 > t0.c0))";
2526 Observe that the condition on C<c2> in the subquery refers to
2527 column C<t0.c0> of the main query: this is I<not> a bind
2528 value, so we have to express it through a scalar ref.
2529 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2530 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2531 what we wanted here.
2533 Finally, here is an example where a subquery is used
2534 for expressing unary negation:
2536 my ($sub_stmt, @sub_bind)
2537 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2538 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2540 lname => {like => '%son%'},
2541 \["NOT ($sub_stmt)" => @sub_bind],
2546 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2547 @bind = ('%son%', 10, 20)
2549 =head3 Deprecated usage of Literal SQL
2551 Below are some examples of archaic use of literal SQL. It is shown only as
2552 reference for those who deal with legacy code. Each example has a much
2553 better, cleaner and safer alternative that users should opt for in new code.
2559 my %where = ( requestor => \'IS NOT NULL' )
2561 $stmt = "WHERE requestor IS NOT NULL"
2563 This used to be the way of generating NULL comparisons, before the handling
2564 of C<undef> got formalized. For new code please use the superior syntax as
2565 described in L</Tests for NULL values>.
2569 my %where = ( requestor => \'= submitter' )
2571 $stmt = "WHERE requestor = submitter"
2573 This used to be the only way to compare columns. Use the superior L</-ident>
2574 method for all new code. For example an identifier declared in such a way
2575 will be properly quoted if L</quote_char> is properly set, while the legacy
2576 form will remain as supplied.
2580 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2582 $stmt = "WHERE completed > ? AND is_ready"
2583 @bind = ('2012-12-21')
2585 Using an empty string literal used to be the only way to express a boolean.
2586 For all new code please use the much more readable
2587 L<-bool|/Unary operators: bool> operator.
2593 These pages could go on for a while, since the nesting of the data
2594 structures this module can handle are pretty much unlimited (the
2595 module implements the C<WHERE> expansion as a recursive function
2596 internally). Your best bet is to "play around" with the module a
2597 little to see how the data structures behave, and choose the best
2598 format for your data based on that.
2600 And of course, all the values above will probably be replaced with
2601 variables gotten from forms or the command line. After all, if you
2602 knew everything ahead of time, you wouldn't have to worry about
2603 dynamically-generating SQL and could just hardwire it into your
2606 =head1 ORDER BY CLAUSES
2608 Some functions take an order by clause. This can either be a scalar (just a
2609 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2610 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2613 Given | Will Generate
2614 ---------------------------------------------------------------
2616 'colA' | ORDER BY colA
2618 [qw/colA colB/] | ORDER BY colA, colB
2620 {-asc => 'colA'} | ORDER BY colA ASC
2622 {-desc => 'colB'} | ORDER BY colB DESC
2624 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2626 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2628 \'colA DESC' | ORDER BY colA DESC
2630 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2631 | /* ...with $x bound to ? */
2634 { -asc => 'colA' }, | colA ASC,
2635 { -desc => [qw/colB/] }, | colB DESC,
2636 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2637 \'colE DESC', | colE DESC,
2638 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2639 ] | /* ...with $x bound to ? */
2640 ===============================================================
2644 =head1 SPECIAL OPERATORS
2646 my $sqlmaker = SQL::Abstract->new(special_ops => [
2650 my ($self, $field, $op, $arg) = @_;
2656 handler => 'method_name',
2660 A "special operator" is a SQL syntactic clause that can be
2661 applied to a field, instead of a usual binary operator.
2664 WHERE field IN (?, ?, ?)
2665 WHERE field BETWEEN ? AND ?
2666 WHERE MATCH(field) AGAINST (?, ?)
2668 Special operators IN and BETWEEN are fairly standard and therefore
2669 are builtin within C<SQL::Abstract> (as the overridable methods
2670 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2671 like the MATCH .. AGAINST example above which is specific to MySQL,
2672 you can write your own operator handlers - supply a C<special_ops>
2673 argument to the C<new> method. That argument takes an arrayref of
2674 operator definitions; each operator definition is a hashref with two
2681 the regular expression to match the operator
2685 Either a coderef or a plain scalar method name. In both cases
2686 the expected return is C<< ($sql, @bind) >>.
2688 When supplied with a method name, it is simply called on the
2689 L<SQL::Abstract> object as:
2691 $self->$method_name($field, $op, $arg)
2695 $field is the LHS of the operator
2696 $op is the part that matched the handler regex
2699 When supplied with a coderef, it is called as:
2701 $coderef->($self, $field, $op, $arg)
2706 For example, here is an implementation
2707 of the MATCH .. AGAINST syntax for MySQL
2709 my $sqlmaker = SQL::Abstract->new(special_ops => [
2711 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2712 {regex => qr/^match$/i,
2714 my ($self, $field, $op, $arg) = @_;
2715 $arg = [$arg] if not ref $arg;
2716 my $label = $self->_quote($field);
2717 my ($placeholder) = $self->_convert('?');
2718 my $placeholders = join ", ", (($placeholder) x @$arg);
2719 my $sql = $self->_sqlcase('match') . " ($label) "
2720 . $self->_sqlcase('against') . " ($placeholders) ";
2721 my @bind = $self->_bindtype($field, @$arg);
2722 return ($sql, @bind);
2729 =head1 UNARY OPERATORS
2731 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2735 my ($self, $op, $arg) = @_;
2741 handler => 'method_name',
2745 A "unary operator" is a SQL syntactic clause that can be
2746 applied to a field - the operator goes before the field
2748 You can write your own operator handlers - supply a C<unary_ops>
2749 argument to the C<new> method. That argument takes an arrayref of
2750 operator definitions; each operator definition is a hashref with two
2757 the regular expression to match the operator
2761 Either a coderef or a plain scalar method name. In both cases
2762 the expected return is C<< $sql >>.
2764 When supplied with a method name, it is simply called on the
2765 L<SQL::Abstract> object as:
2767 $self->$method_name($op, $arg)
2771 $op is the part that matched the handler regex
2772 $arg is the RHS or argument of the operator
2774 When supplied with a coderef, it is called as:
2776 $coderef->($self, $op, $arg)
2784 Thanks to some benchmarking by Mark Stosberg, it turns out that
2785 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2786 I must admit this wasn't an intentional design issue, but it's a
2787 byproduct of the fact that you get to control your C<DBI> handles
2790 To maximize performance, use a code snippet like the following:
2792 # prepare a statement handle using the first row
2793 # and then reuse it for the rest of the rows
2795 for my $href (@array_of_hashrefs) {
2796 $stmt ||= $sql->insert('table', $href);
2797 $sth ||= $dbh->prepare($stmt);
2798 $sth->execute($sql->values($href));
2801 The reason this works is because the keys in your C<$href> are sorted
2802 internally by B<SQL::Abstract>. Thus, as long as your data retains
2803 the same structure, you only have to generate the SQL the first time
2804 around. On subsequent queries, simply use the C<values> function provided
2805 by this module to return your values in the correct order.
2807 However this depends on the values having the same type - if, for
2808 example, the values of a where clause may either have values
2809 (resulting in sql of the form C<column = ?> with a single bind
2810 value), or alternatively the values might be C<undef> (resulting in
2811 sql of the form C<column IS NULL> with no bind value) then the
2812 caching technique suggested will not work.
2816 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2817 really like this part (I do, at least). Building up a complex query
2818 can be as simple as the following:
2825 use CGI::FormBuilder;
2828 my $form = CGI::FormBuilder->new(...);
2829 my $sql = SQL::Abstract->new;
2831 if ($form->submitted) {
2832 my $field = $form->field;
2833 my $id = delete $field->{id};
2834 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2837 Of course, you would still have to connect using C<DBI> to run the
2838 query, but the point is that if you make your form look like your
2839 table, the actual query script can be extremely simplistic.
2841 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2842 a fast interface to returning and formatting data. I frequently
2843 use these three modules together to write complex database query
2844 apps in under 50 lines.
2846 =head1 HOW TO CONTRIBUTE
2848 Contributions are always welcome, in all usable forms (we especially
2849 welcome documentation improvements). The delivery methods include git-
2850 or unified-diff formatted patches, GitHub pull requests, or plain bug
2851 reports either via RT or the Mailing list. Contributors are generally
2852 granted full access to the official repository after their first several
2853 patches pass successful review.
2855 This project is maintained in a git repository. The code and related tools are
2856 accessible at the following locations:
2860 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2862 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2864 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2866 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2872 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2873 Great care has been taken to preserve the I<published> behavior
2874 documented in previous versions in the 1.* family; however,
2875 some features that were previously undocumented, or behaved
2876 differently from the documentation, had to be changed in order
2877 to clarify the semantics. Hence, client code that was relying
2878 on some dark areas of C<SQL::Abstract> v1.*
2879 B<might behave differently> in v1.50.
2881 The main changes are:
2887 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2891 support for the { operator => \"..." } construct (to embed literal SQL)
2895 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2899 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2903 defensive programming: check arguments
2907 fixed bug with global logic, which was previously implemented
2908 through global variables yielding side-effects. Prior versions would
2909 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2910 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2911 Now this is interpreted
2912 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2917 fixed semantics of _bindtype on array args
2921 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2922 we just avoid shifting arrays within that tree.
2926 dropped the C<_modlogic> function
2930 =head1 ACKNOWLEDGEMENTS
2932 There are a number of individuals that have really helped out with
2933 this module. Unfortunately, most of them submitted bugs via CPAN
2934 so I have no idea who they are! But the people I do know are:
2936 Ash Berlin (order_by hash term support)
2937 Matt Trout (DBIx::Class support)
2938 Mark Stosberg (benchmarking)
2939 Chas Owens (initial "IN" operator support)
2940 Philip Collins (per-field SQL functions)
2941 Eric Kolve (hashref "AND" support)
2942 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2943 Dan Kubb (support for "quote_char" and "name_sep")
2944 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2945 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2946 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2947 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2948 Oliver Charles (support for "RETURNING" after "INSERT")
2954 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
2958 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
2960 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
2962 For support, your best bet is to try the C<DBIx::Class> users mailing list.
2963 While not an official support venue, C<DBIx::Class> makes heavy use of
2964 C<SQL::Abstract>, and as such list members there are very familiar with
2965 how to create queries.
2969 This module is free software; you may copy this under the same
2970 terms as perl itself (either the GNU General Public License or
2971 the Artistic License)