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;
164 $opt{unary_ops} ||= [];
166 # rudimentary sanity-check for user supplied bits treated as functions/operators
167 # If a purported function matches this regular expression, an exception is thrown.
168 # Literal SQL is *NOT* subject to this check, only functions (and column names
169 # when quoting is not in effect)
172 # need to guard against ()'s in column names too, but this will break tons of
173 # hacks... ideas anyone?
174 $opt{injection_guard} ||= qr/
180 $opt{node_types} = +{
181 map +("-$_" => '_render_'.$_),
182 qw(op func value bind ident literal)
185 $opt{expand_unary} = {};
187 return bless \%opt, $class;
190 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
191 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
193 sub _assert_pass_injection_guard {
194 if ($_[1] =~ $_[0]->{injection_guard}) {
195 my $class = ref $_[0];
196 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
197 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
198 . "{injection_guard} attribute to ${class}->new()"
203 #======================================================================
205 #======================================================================
209 my $table = $self->_table(shift);
210 my $data = shift || return;
213 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
214 my ($sql, @bind) = $self->$method($data);
215 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
217 if ($options->{returning}) {
218 my ($s, @b) = $self->_insert_returning($options);
223 return wantarray ? ($sql, @bind) : $sql;
226 # So that subclasses can override INSERT ... RETURNING separately from
227 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
228 sub _insert_returning { shift->_returning(@_) }
231 my ($self, $options) = @_;
233 my $f = $options->{returning};
235 my ($sql, @bind) = $self->_render_expr(
236 $self->_expand_maybe_list_expr($f, undef, -ident)
239 ? $self->_sqlcase(' returning ') . $sql
240 : ($self->_sqlcase(' returning ').$sql, @bind);
243 sub _insert_HASHREF { # explicit list of fields and then values
244 my ($self, $data) = @_;
246 my @fields = sort keys %$data;
248 my ($sql, @bind) = $self->_insert_values($data);
251 $_ = $self->_quote($_) foreach @fields;
252 $sql = "( ".join(", ", @fields).") ".$sql;
254 return ($sql, @bind);
257 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
258 my ($self, $data) = @_;
260 # no names (arrayref) so can't generate bindtype
261 $self->{bindtype} ne 'columns'
262 or belch "can't do 'columns' bindtype when called with arrayref";
264 my (@values, @all_bind);
265 foreach my $value (@$data) {
266 my ($values, @bind) = $self->_insert_value(undef, $value);
267 push @values, $values;
268 push @all_bind, @bind;
270 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
271 return ($sql, @all_bind);
274 sub _insert_ARRAYREFREF { # literal SQL with bind
275 my ($self, $data) = @_;
277 my ($sql, @bind) = @${$data};
278 $self->_assert_bindval_matches_bindtype(@bind);
280 return ($sql, @bind);
284 sub _insert_SCALARREF { # literal SQL without bind
285 my ($self, $data) = @_;
291 my ($self, $data) = @_;
293 my (@values, @all_bind);
294 foreach my $column (sort keys %$data) {
295 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
296 push @values, $values;
297 push @all_bind, @bind;
299 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
300 return ($sql, @all_bind);
304 my ($self, $column, $v) = @_;
306 return $self->_render_expr(
307 $self->_expand_insert_value($column, $v)
311 sub _expand_insert_value {
312 my ($self, $column, $v) = @_;
314 if (ref($v) eq 'ARRAY') {
315 if ($self->{array_datatypes}) {
316 return +{ -bind => [ $column, $v ] };
318 my ($sql, @bind) = @$v;
319 $self->_assert_bindval_matches_bindtype(@bind);
320 return +{ -literal => $v };
322 if (ref($v) eq 'HASH') {
323 if (grep !/^-/, keys %$v) {
324 belch "HASH ref as bind value in insert is not supported";
325 return +{ -bind => [ $column, $v ] };
329 return +{ -bind => [ $column, undef ] };
331 local our $Cur_Col_Meta = $column;
332 return $self->_expand_expr($v);
337 #======================================================================
339 #======================================================================
344 my $table = $self->_table(shift);
345 my $data = shift || return;
349 # first build the 'SET' part of the sql statement
350 puke "Unsupported data type specified to \$sql->update"
351 unless ref $data eq 'HASH';
353 my ($sql, @all_bind) = $self->_update_set_values($data);
354 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
358 my($where_sql, @where_bind) = $self->where($where);
360 push @all_bind, @where_bind;
363 if ($options->{returning}) {
364 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
365 $sql .= $returning_sql;
366 push @all_bind, @returning_bind;
369 return wantarray ? ($sql, @all_bind) : $sql;
372 sub _update_set_values {
373 my ($self, $data) = @_;
375 return $self->_render_expr(
376 $self->_expand_update_set_values($data),
380 sub _expand_update_set_values {
381 my ($self, $data) = @_;
382 $self->_expand_maybe_list_expr( [
385 +{ -op => [ '=', { -ident => $k }, $set ] };
391 ? ($self->{array_datatypes}
392 ? [ $k, +{ -bind => [ $k, $v ] } ]
393 : [ $k, +{ -literal => $v } ])
395 local our $Cur_Col_Meta = $k;
396 [ $k, $self->_expand_expr($v) ]
403 # So that subclasses can override UPDATE ... RETURNING separately from
405 sub _update_returning { shift->_returning(@_) }
409 #======================================================================
411 #======================================================================
416 my $table = $self->_table(shift);
417 my $fields = shift || '*';
421 my ($fields_sql, @bind) = $self->_select_fields($fields);
423 my ($where_sql, @where_bind) = $self->where($where, $order);
424 push @bind, @where_bind;
426 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
427 $self->_sqlcase('from'), $table)
430 return wantarray ? ($sql, @bind) : $sql;
434 my ($self, $fields) = @_;
435 return $self->_render_expr(
436 $self->_expand_maybe_list_expr($fields, undef, '-ident')
440 #======================================================================
442 #======================================================================
447 my $table = $self->_table(shift);
451 my($where_sql, @bind) = $self->where($where);
452 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
454 if ($options->{returning}) {
455 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
456 $sql .= $returning_sql;
457 push @bind, @returning_bind;
460 return wantarray ? ($sql, @bind) : $sql;
463 # So that subclasses can override DELETE ... RETURNING separately from
465 sub _delete_returning { shift->_returning(@_) }
469 #======================================================================
471 #======================================================================
475 # Finally, a separate routine just to handle WHERE clauses
477 my ($self, $where, $order) = @_;
479 local $self->{convert_where} = $self->{convert};
482 my ($sql, @bind) = defined($where)
483 ? $self->_recurse_where($where)
485 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
489 my ($order_sql, @order_bind) = $self->_order_by($order);
491 push @bind, @order_bind;
494 return wantarray ? ($sql, @bind) : $sql;
498 my ($self, $expr, $logic, $default_scalar_to) = @_;
499 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
500 return undef unless defined($expr);
501 if (ref($expr) eq 'HASH') {
502 if (keys %$expr > 1) {
506 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
510 return unless %$expr;
511 return $self->_expand_expr_hashpair(%$expr, $logic);
513 if (ref($expr) eq 'ARRAY') {
514 my $logic = lc($logic || $self->{logic});
515 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
521 while (my ($el) = splice @expr, 0, 1) {
522 puke "Supplying an empty left hand side argument is not supported in array-pairs"
523 unless defined($el) and length($el);
524 my $elref = ref($el);
526 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
527 } elsif ($elref eq 'ARRAY') {
528 push(@res, $self->_expand_expr($el)) if @$el;
529 } elsif (my $l = is_literal_value($el)) {
530 push @res, { -literal => $l };
531 } elsif ($elref eq 'HASH') {
532 push @res, $self->_expand_expr($el);
537 return { -op => [ $logic, @res ] };
539 if (my $literal = is_literal_value($expr)) {
540 return +{ -literal => $literal };
542 if (!ref($expr) or Scalar::Util::blessed($expr)) {
543 if (my $d = $Default_Scalar_To) {
544 return +{ $d => $expr };
546 if (my $m = our $Cur_Col_Meta) {
547 return +{ -bind => [ $m, $expr ] };
549 return +{ -value => $expr };
554 sub _expand_expr_hashpair {
555 my ($self, $k, $v, $logic) = @_;
556 unless (defined($k) and length($k)) {
557 if (defined($k) and my $literal = is_literal_value($v)) {
558 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
559 return { -literal => $literal };
561 puke "Supplying an empty left hand side argument is not supported";
564 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
565 if ($k =~ s/ [_\s]? \d+ $//x ) {
566 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
567 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
570 return $self->_expand_expr($v);
574 return $self->_expand_expr($v);
576 puke "-bool => undef not supported" unless defined($v);
577 return { -ident => $v };
580 return { -op => [ 'not', $self->_expand_expr($v) ] };
582 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
585 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
588 if (my ($logic) = $k =~ /^-(and|or)$/i) {
589 if (ref($v) eq 'HASH') {
590 return $self->_expand_expr($v, $logic);
592 if (ref($v) eq 'ARRAY') {
593 return $self->_expand_expr($v, $logic);
598 $op =~ s/^-// if length($op) > 1;
600 # top level special ops are illegal in general
601 puke "Illegal use of top-level '-$op'"
602 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
603 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
604 return { -op => [ $op, $v ] };
607 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
608 return +{ -bind => [ $m, $v ] };
610 if (my $custom = $self->{expand_unary}{$k}) {
611 return $self->$custom($v);
613 if ($self->{node_types}{$k}) {
619 and (keys %$v)[0] =~ /^-/
621 my ($func) = $k =~ /^-(.*)$/;
622 return +{ -func => [ $func, $self->_expand_expr($v) ] };
624 if (!ref($v) or is_literal_value($v)) {
625 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
632 and exists $v->{-value}
633 and not defined $v->{-value}
636 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
638 if (!ref($v) or Scalar::Util::blessed($v)) {
639 my $d = our $Default_Scalar_To;
644 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
648 if (ref($v) eq 'HASH') {
652 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
659 $self->_assert_pass_injection_guard($vk);
660 if ($vk =~ s/ [_\s]? \d+ $//x ) {
661 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
662 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
664 if ($vk =~ /^(?:not[ _])?between$/) {
665 local our $Cur_Col_Meta = $k;
666 my @rhs = map $self->_expand_expr($_),
667 ref($vv) eq 'ARRAY' ? @$vv : $vv;
669 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
671 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
673 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
676 join(' ', split '_', $vk),
681 if ($vk =~ /^(?:not[ _])?in$/) {
682 if (my $literal = is_literal_value($vv)) {
683 my ($sql, @bind) = @$literal;
684 my $opened_sql = $self->_open_outer_paren($sql);
686 $vk, { -ident => $k },
687 [ { -literal => [ $opened_sql, @bind ] } ]
691 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
692 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
693 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
694 . 'will emit the logically correct SQL instead of raising this exception)'
696 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
698 my @rhs = map $self->_expand_expr($_),
699 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
700 map { defined($_) ? $_: puke($undef_err) }
701 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
702 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
705 join(' ', split '_', $vk),
710 if ($vk eq 'ident') {
711 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
712 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
720 if ($vk eq 'value') {
721 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
725 { -bind => [ $k, $vv ] }
728 if ($vk =~ /^is(?:[ _]not)?$/) {
729 puke "$vk can only take undef as argument"
733 and exists($vv->{-value})
734 and !defined($vv->{-value})
737 return +{ -op => [ $vk.' null', { -ident => $k } ] };
739 if ($vk =~ /^(and|or)$/) {
740 if (ref($vv) eq 'HASH') {
743 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
748 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
749 return { -op => [ $vk, { -ident => $k }, $vv ] };
751 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
755 { -op => [ $vk, $vv ] }
758 if (ref($vv) eq 'ARRAY') {
759 my ($logic, @values) = (
760 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
765 $vk =~ $self->{inequality_op}
766 or join(' ', split '_', $vk) =~ $self->{not_like_op}
768 if (lc($logic) eq '-or' and @values > 1) {
769 my $op = uc join ' ', split '_', $vk;
770 belch "A multi-element arrayref as an argument to the inequality op '$op' "
771 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
772 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
777 # try to DWIM on equality operators
778 my $op = join ' ', split '_', $vk;
780 $op =~ $self->{equality_op} ? $self->sqlfalse
781 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
782 : $op =~ $self->{inequality_op} ? $self->sqltrue
783 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
784 : puke "operator '$op' applied on an empty array (field '$k')";
788 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
796 and exists $vv->{-value}
797 and not defined $vv->{-value}
800 my $op = join ' ', split '_', $vk;
802 $op =~ /^not$/i ? 'is not' # legacy
803 : $op =~ $self->{equality_op} ? 'is'
804 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
805 : $op =~ $self->{inequality_op} ? 'is not'
806 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
807 : puke "unexpected operator '$op' with undef operand";
808 return +{ -op => [ $is.' null', { -ident => $k } ] };
810 local our $Cur_Col_Meta = $k;
814 $self->_expand_expr($vv)
817 if (ref($v) eq 'ARRAY') {
818 return $self->sqlfalse unless @$v;
819 $self->_debug("ARRAY($k) means distribute over elements");
821 $v->[0] =~ /^-((?:and|or))$/i
822 ? ($v = [ @{$v}[1..$#$v] ], $1)
823 : ($self->{logic} || 'or')
827 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
830 if (my $literal = is_literal_value($v)) {
832 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
835 my ($sql, @bind) = @$literal;
836 if ($self->{bindtype} eq 'columns') {
838 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
839 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
843 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
849 my ($self, $expr) = @_;
850 my ($k, $v, @rest) = %$expr;
852 if (my $meth = $self->{node_types}{$k}) {
853 return $self->$meth($v);
855 die "notreached: $k";
859 my ($self, $where, $logic) = @_;
861 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
863 my $where_exp = $self->_expand_expr($where, $logic);
865 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
867 # dispatch on appropriate method according to refkind of $where
868 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
870 # my ($sql, @bind) = $self->$method($where_exp, $logic);
872 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
874 # DBIx::Class used to call _recurse_where in scalar context
875 # something else might too...
877 return ($sql, @bind);
880 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
886 my ($self, $ident) = @_;
888 return $self->_convert($self->_quote($ident));
892 my ($self, $value) = @_;
894 return ($self->_convert('?'), $self->_bindtype(undef, $value));
897 my %unop_postfix = map +($_ => 1),
898 'is null', 'is not null',
906 my ($self, $args) = @_;
907 my ($left, $low, $high) = @$args;
908 my ($rhsql, @rhbind) = do {
910 puke "Single arg to between must be a literal"
911 unless $low->{-literal};
914 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
915 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
916 @{$l}[1..$#$l], @{$h}[1..$#$h])
919 my ($lhsql, @lhbind) = $self->_render_expr($left);
921 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
925 }), 'between', 'not between'),
929 my ($self, $args) = @_;
930 my ($lhs, $rhs) = @$args;
933 my ($sql, @bind) = $self->_render_expr($_);
934 push @in_bind, @bind;
937 my ($lhsql, @lbind) = $self->_render_expr($lhs);
939 $lhsql.' '.$self->_sqlcase($op).' ( '
950 my ($op, @args) = @$v;
951 $op =~ s/^-// if length($op) > 1;
953 if (my $h = $special{$op}) {
954 return $self->$h(\@args);
956 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
957 puke "Special op '${op}' requires first value to be identifier"
958 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
959 return $self->${\($us->{handler})}($k, $op, $args[1]);
961 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
962 return $self->${\($us->{handler})}($op, $args[0]);
964 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
965 if (@args == 1 and $op !~ /^(and|or)$/) {
966 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
967 my $op_sql = $self->_sqlcase($final_op);
969 $unop_postfix{lc($final_op)}
970 ? "${expr_sql} ${op_sql}"
971 : "${op_sql} ${expr_sql}"
973 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
975 my @parts = map [ $self->_render_expr($_) ], @args;
976 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
977 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
982 map @{$_}[1..$#$_], @parts
989 my ($self, $rest) = @_;
990 my ($func, @args) = @$rest;
994 push @arg_sql, shift @x;
996 } map [ $self->_render_expr($_) ], @args;
997 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1001 my ($self, $bind) = @_;
1002 return ($self->_convert('?'), $self->_bindtype(@$bind));
1005 sub _render_literal {
1006 my ($self, $literal) = @_;
1007 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1011 # Some databases (SQLite) treat col IN (1, 2) different from
1012 # col IN ( (1, 2) ). Use this to strip all outer parens while
1013 # adding them back in the corresponding method
1014 sub _open_outer_paren {
1015 my ($self, $sql) = @_;
1017 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1019 # there are closing parens inside, need the heavy duty machinery
1020 # to reevaluate the extraction starting from $sql (full reevaluation)
1021 if ($inner =~ /\)/) {
1022 require Text::Balanced;
1024 my (undef, $remainder) = do {
1025 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1027 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1030 # the entire expression needs to be a balanced bracketed thing
1031 # (after an extract no remainder sans trailing space)
1032 last if defined $remainder and $remainder =~ /\S/;
1042 #======================================================================
1044 #======================================================================
1047 my ($self, $arg) = @_;
1049 return '' unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1051 my $expander = sub {
1052 my ($self, $dir, $expr) = @_;
1053 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1054 map $self->_expand_expr($_, undef, -ident),
1055 ref($expr) eq 'ARRAY' ? @$expr : $expr;
1056 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1062 and grep /^-(asc|desc)$/, keys %$arg
1064 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1067 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1068 sub { shift->$expander(asc => @_) },
1069 sub { shift->$expander(desc => @_) },
1072 my $expanded = $self->$expander(undef, $arg);
1074 my ($sql, @bind) = $self->_render_expr($expanded);
1076 my $final_sql = $self->_sqlcase(' order by ').$sql;
1078 return wantarray ? ($final_sql, @bind) : $final_sql;
1081 #======================================================================
1082 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1083 #======================================================================
1088 ($self->_render_expr(
1089 $self->_expand_maybe_list_expr($from, undef, -ident)
1094 #======================================================================
1096 #======================================================================
1098 sub _expand_maybe_list_expr {
1099 my ($self, $expr, $logic, $default) = @_;
1101 if (ref($expr) eq 'ARRAY') {
1103 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1110 return $self->_expand_expr($e, $logic, $default);
1113 # highly optimized, as it's called way too often
1115 # my ($self, $label) = @_;
1117 return '' unless defined $_[1];
1118 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1119 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1121 unless ($_[0]->{quote_char}) {
1122 if (ref($_[1]) eq 'ARRAY') {
1123 return join($_[0]->{name_sep}||'.', @{$_[1]});
1125 $_[0]->_assert_pass_injection_guard($_[1]);
1130 my $qref = ref $_[0]->{quote_char};
1132 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1133 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1134 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1136 my $esc = $_[0]->{escape_char} || $r;
1138 # parts containing * are naturally unquoted
1140 $_[0]->{name_sep}||'',
1144 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1146 (ref($_[1]) eq 'ARRAY'
1150 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1158 # Conversion, if applicable
1160 #my ($self, $arg) = @_;
1161 if ($_[0]->{convert_where}) {
1162 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1169 #my ($self, $col, @vals) = @_;
1170 # called often - tighten code
1171 return $_[0]->{bindtype} eq 'columns'
1172 ? map {[$_[1], $_]} @_[2 .. $#_]
1177 # Dies if any element of @bind is not in [colname => value] format
1178 # if bindtype is 'columns'.
1179 sub _assert_bindval_matches_bindtype {
1180 # my ($self, @bind) = @_;
1182 if ($self->{bindtype} eq 'columns') {
1184 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1185 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1191 sub _join_sql_clauses {
1192 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1194 if (@$clauses_aref > 1) {
1195 my $join = " " . $self->_sqlcase($logic) . " ";
1196 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1197 return ($sql, @$bind_aref);
1199 elsif (@$clauses_aref) {
1200 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1203 return (); # if no SQL, ignore @$bind_aref
1208 # Fix SQL case, if so requested
1210 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1211 # don't touch the argument ... crooked logic, but let's not change it!
1212 return $_[0]->{case} ? $_[1] : uc($_[1]);
1216 #======================================================================
1217 # DISPATCHING FROM REFKIND
1218 #======================================================================
1221 my ($self, $data) = @_;
1223 return 'UNDEF' unless defined $data;
1225 # blessed objects are treated like scalars
1226 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1228 return 'SCALAR' unless $ref;
1231 while ($ref eq 'REF') {
1233 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1237 return ($ref||'SCALAR') . ('REF' x $n_steps);
1241 my ($self, $data) = @_;
1242 my @try = ($self->_refkind($data));
1243 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1244 push @try, 'FALLBACK';
1248 sub _METHOD_FOR_refkind {
1249 my ($self, $meth_prefix, $data) = @_;
1252 for (@{$self->_try_refkind($data)}) {
1253 $method = $self->can($meth_prefix."_".$_)
1257 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1261 sub _SWITCH_refkind {
1262 my ($self, $data, $dispatch_table) = @_;
1265 for (@{$self->_try_refkind($data)}) {
1266 $coderef = $dispatch_table->{$_}
1270 puke "no dispatch entry for ".$self->_refkind($data)
1279 #======================================================================
1280 # VALUES, GENERATE, AUTOLOAD
1281 #======================================================================
1283 # LDNOTE: original code from nwiger, didn't touch code in that section
1284 # I feel the AUTOLOAD stuff should not be the default, it should
1285 # only be activated on explicit demand by user.
1289 my $data = shift || return;
1290 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1291 unless ref $data eq 'HASH';
1294 foreach my $k (sort keys %$data) {
1295 my $v = $data->{$k};
1296 $self->_SWITCH_refkind($v, {
1298 if ($self->{array_datatypes}) { # array datatype
1299 push @all_bind, $self->_bindtype($k, $v);
1301 else { # literal SQL with bind
1302 my ($sql, @bind) = @$v;
1303 $self->_assert_bindval_matches_bindtype(@bind);
1304 push @all_bind, @bind;
1307 ARRAYREFREF => sub { # literal SQL with bind
1308 my ($sql, @bind) = @${$v};
1309 $self->_assert_bindval_matches_bindtype(@bind);
1310 push @all_bind, @bind;
1312 SCALARREF => sub { # literal SQL without bind
1314 SCALAR_or_UNDEF => sub {
1315 push @all_bind, $self->_bindtype($k, $v);
1326 my(@sql, @sqlq, @sqlv);
1330 if ($ref eq 'HASH') {
1331 for my $k (sort keys %$_) {
1334 my $label = $self->_quote($k);
1335 if ($r eq 'ARRAY') {
1336 # literal SQL with bind
1337 my ($sql, @bind) = @$v;
1338 $self->_assert_bindval_matches_bindtype(@bind);
1339 push @sqlq, "$label = $sql";
1341 } elsif ($r eq 'SCALAR') {
1342 # literal SQL without bind
1343 push @sqlq, "$label = $$v";
1345 push @sqlq, "$label = ?";
1346 push @sqlv, $self->_bindtype($k, $v);
1349 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1350 } elsif ($ref eq 'ARRAY') {
1351 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1354 if ($r eq 'ARRAY') { # literal SQL with bind
1355 my ($sql, @bind) = @$v;
1356 $self->_assert_bindval_matches_bindtype(@bind);
1359 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1360 # embedded literal SQL
1367 push @sql, '(' . join(', ', @sqlq) . ')';
1368 } elsif ($ref eq 'SCALAR') {
1372 # strings get case twiddled
1373 push @sql, $self->_sqlcase($_);
1377 my $sql = join ' ', @sql;
1379 # this is pretty tricky
1380 # if ask for an array, return ($stmt, @bind)
1381 # otherwise, s/?/shift @sqlv/ to put it inline
1383 return ($sql, @sqlv);
1385 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1386 ref $d ? $d->[1] : $d/e;
1395 # This allows us to check for a local, then _form, attr
1397 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1398 return $self->generate($name, @_);
1409 SQL::Abstract - Generate SQL from Perl data structures
1415 my $sql = SQL::Abstract->new;
1417 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1419 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1421 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1423 my($stmt, @bind) = $sql->delete($table, \%where);
1425 # Then, use these in your DBI statements
1426 my $sth = $dbh->prepare($stmt);
1427 $sth->execute(@bind);
1429 # Just generate the WHERE clause
1430 my($stmt, @bind) = $sql->where(\%where, $order);
1432 # Return values in the same order, for hashed queries
1433 # See PERFORMANCE section for more details
1434 my @bind = $sql->values(\%fieldvals);
1438 This module was inspired by the excellent L<DBIx::Abstract>.
1439 However, in using that module I found that what I really wanted
1440 to do was generate SQL, but still retain complete control over my
1441 statement handles and use the DBI interface. So, I set out to
1442 create an abstract SQL generation module.
1444 While based on the concepts used by L<DBIx::Abstract>, there are
1445 several important differences, especially when it comes to WHERE
1446 clauses. I have modified the concepts used to make the SQL easier
1447 to generate from Perl data structures and, IMO, more intuitive.
1448 The underlying idea is for this module to do what you mean, based
1449 on the data structures you provide it. The big advantage is that
1450 you don't have to modify your code every time your data changes,
1451 as this module figures it out.
1453 To begin with, an SQL INSERT is as easy as just specifying a hash
1454 of C<key=value> pairs:
1457 name => 'Jimbo Bobson',
1458 phone => '123-456-7890',
1459 address => '42 Sister Lane',
1460 city => 'St. Louis',
1461 state => 'Louisiana',
1464 The SQL can then be generated with this:
1466 my($stmt, @bind) = $sql->insert('people', \%data);
1468 Which would give you something like this:
1470 $stmt = "INSERT INTO people
1471 (address, city, name, phone, state)
1472 VALUES (?, ?, ?, ?, ?)";
1473 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1474 '123-456-7890', 'Louisiana');
1476 These are then used directly in your DBI code:
1478 my $sth = $dbh->prepare($stmt);
1479 $sth->execute(@bind);
1481 =head2 Inserting and Updating Arrays
1483 If your database has array types (like for example Postgres),
1484 activate the special option C<< array_datatypes => 1 >>
1485 when creating the C<SQL::Abstract> object.
1486 Then you may use an arrayref to insert and update database array types:
1488 my $sql = SQL::Abstract->new(array_datatypes => 1);
1490 planets => [qw/Mercury Venus Earth Mars/]
1493 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1497 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1499 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1502 =head2 Inserting and Updating SQL
1504 In order to apply SQL functions to elements of your C<%data> you may
1505 specify a reference to an arrayref for the given hash value. For example,
1506 if you need to execute the Oracle C<to_date> function on a value, you can
1507 say something like this:
1511 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1514 The first value in the array is the actual SQL. Any other values are
1515 optional and would be included in the bind values array. This gives
1518 my($stmt, @bind) = $sql->insert('people', \%data);
1520 $stmt = "INSERT INTO people (name, date_entered)
1521 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1522 @bind = ('Bill', '03/02/2003');
1524 An UPDATE is just as easy, all you change is the name of the function:
1526 my($stmt, @bind) = $sql->update('people', \%data);
1528 Notice that your C<%data> isn't touched; the module will generate
1529 the appropriately quirky SQL for you automatically. Usually you'll
1530 want to specify a WHERE clause for your UPDATE, though, which is
1531 where handling C<%where> hashes comes in handy...
1533 =head2 Complex where statements
1535 This module can generate pretty complicated WHERE statements
1536 easily. For example, simple C<key=value> pairs are taken to mean
1537 equality, and if you want to see if a field is within a set
1538 of values, you can use an arrayref. Let's say we wanted to
1539 SELECT some data based on this criteria:
1542 requestor => 'inna',
1543 worker => ['nwiger', 'rcwe', 'sfz'],
1544 status => { '!=', 'completed' }
1547 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1549 The above would give you something like this:
1551 $stmt = "SELECT * FROM tickets WHERE
1552 ( requestor = ? ) AND ( status != ? )
1553 AND ( worker = ? OR worker = ? OR worker = ? )";
1554 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1556 Which you could then use in DBI code like so:
1558 my $sth = $dbh->prepare($stmt);
1559 $sth->execute(@bind);
1565 The methods are simple. There's one for every major SQL operation,
1566 and a constructor you use first. The arguments are specified in a
1567 similar order for each method (table, then fields, then a where
1568 clause) to try and simplify things.
1570 =head2 new(option => 'value')
1572 The C<new()> function takes a list of options and values, and returns
1573 a new B<SQL::Abstract> object which can then be used to generate SQL
1574 through the methods below. The options accepted are:
1580 If set to 'lower', then SQL will be generated in all lowercase. By
1581 default SQL is generated in "textbook" case meaning something like:
1583 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1585 Any setting other than 'lower' is ignored.
1589 This determines what the default comparison operator is. By default
1590 it is C<=>, meaning that a hash like this:
1592 %where = (name => 'nwiger', email => 'nate@wiger.org');
1594 Will generate SQL like this:
1596 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1598 However, you may want loose comparisons by default, so if you set
1599 C<cmp> to C<like> you would get SQL such as:
1601 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1603 You can also override the comparison on an individual basis - see
1604 the huge section on L</"WHERE CLAUSES"> at the bottom.
1606 =item sqltrue, sqlfalse
1608 Expressions for inserting boolean values within SQL statements.
1609 By default these are C<1=1> and C<1=0>. They are used
1610 by the special operators C<-in> and C<-not_in> for generating
1611 correct SQL even when the argument is an empty array (see below).
1615 This determines the default logical operator for multiple WHERE
1616 statements in arrays or hashes. If absent, the default logic is "or"
1617 for arrays, and "and" for hashes. This means that a WHERE
1621 event_date => {'>=', '2/13/99'},
1622 event_date => {'<=', '4/24/03'},
1625 will generate SQL like this:
1627 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1629 This is probably not what you want given this query, though (look
1630 at the dates). To change the "OR" to an "AND", simply specify:
1632 my $sql = SQL::Abstract->new(logic => 'and');
1634 Which will change the above C<WHERE> to:
1636 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1638 The logic can also be changed locally by inserting
1639 a modifier in front of an arrayref:
1641 @where = (-and => [event_date => {'>=', '2/13/99'},
1642 event_date => {'<=', '4/24/03'} ]);
1644 See the L</"WHERE CLAUSES"> section for explanations.
1648 This will automatically convert comparisons using the specified SQL
1649 function for both column and value. This is mostly used with an argument
1650 of C<upper> or C<lower>, so that the SQL will have the effect of
1651 case-insensitive "searches". For example, this:
1653 $sql = SQL::Abstract->new(convert => 'upper');
1654 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1656 Will turn out the following SQL:
1658 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1660 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1661 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1662 not validate this option; it will just pass through what you specify verbatim).
1666 This is a kludge because many databases suck. For example, you can't
1667 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1668 Instead, you have to use C<bind_param()>:
1670 $sth->bind_param(1, 'reg data');
1671 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1673 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1674 which loses track of which field each slot refers to. Fear not.
1676 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1677 Currently, you can specify either C<normal> (default) or C<columns>. If you
1678 specify C<columns>, you will get an array that looks like this:
1680 my $sql = SQL::Abstract->new(bindtype => 'columns');
1681 my($stmt, @bind) = $sql->insert(...);
1684 [ 'column1', 'value1' ],
1685 [ 'column2', 'value2' ],
1686 [ 'column3', 'value3' ],
1689 You can then iterate through this manually, using DBI's C<bind_param()>.
1691 $sth->prepare($stmt);
1694 my($col, $data) = @$_;
1695 if ($col eq 'details' || $col eq 'comments') {
1696 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1697 } elsif ($col eq 'image') {
1698 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1700 $sth->bind_param($i, $data);
1704 $sth->execute; # execute without @bind now
1706 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1707 Basically, the advantage is still that you don't have to care which fields
1708 are or are not included. You could wrap that above C<for> loop in a simple
1709 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1710 get a layer of abstraction over manual SQL specification.
1712 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1713 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1714 will expect the bind values in this format.
1718 This is the character that a table or column name will be quoted
1719 with. By default this is an empty string, but you could set it to
1720 the character C<`>, to generate SQL like this:
1722 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1724 Alternatively, you can supply an array ref of two items, the first being the left
1725 hand quote character, and the second the right hand quote character. For
1726 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1727 that generates SQL like this:
1729 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1731 Quoting is useful if you have tables or columns names that are reserved
1732 words in your database's SQL dialect.
1736 This is the character that will be used to escape L</quote_char>s appearing
1737 in an identifier before it has been quoted.
1739 The parameter default in case of a single L</quote_char> character is the quote
1742 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1743 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1744 of the B<opening (left)> L</quote_char> within the identifier are currently left
1745 untouched. The default for opening-closing-style quotes may change in future
1746 versions, thus you are B<strongly encouraged> to specify the escape character
1751 This is the character that separates a table and column name. It is
1752 necessary to specify this when the C<quote_char> option is selected,
1753 so that tables and column names can be individually quoted like this:
1755 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1757 =item injection_guard
1759 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1760 column name specified in a query structure. This is a safety mechanism to avoid
1761 injection attacks when mishandling user input e.g.:
1763 my %condition_as_column_value_pairs = get_values_from_user();
1764 $sqla->select( ... , \%condition_as_column_value_pairs );
1766 If the expression matches an exception is thrown. Note that literal SQL
1767 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1769 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1771 =item array_datatypes
1773 When this option is true, arrayrefs in INSERT or UPDATE are
1774 interpreted as array datatypes and are passed directly
1776 When this option is false, arrayrefs are interpreted
1777 as literal SQL, just like refs to arrayrefs
1778 (but this behavior is for backwards compatibility; when writing
1779 new queries, use the "reference to arrayref" syntax
1785 Takes a reference to a list of "special operators"
1786 to extend the syntax understood by L<SQL::Abstract>.
1787 See section L</"SPECIAL OPERATORS"> for details.
1791 Takes a reference to a list of "unary operators"
1792 to extend the syntax understood by L<SQL::Abstract>.
1793 See section L</"UNARY OPERATORS"> for details.
1799 =head2 insert($table, \@values || \%fieldvals, \%options)
1801 This is the simplest function. You simply give it a table name
1802 and either an arrayref of values or hashref of field/value pairs.
1803 It returns an SQL INSERT statement and a list of bind values.
1804 See the sections on L</"Inserting and Updating Arrays"> and
1805 L</"Inserting and Updating SQL"> for information on how to insert
1806 with those data types.
1808 The optional C<\%options> hash reference may contain additional
1809 options to generate the insert SQL. Currently supported options
1816 Takes either a scalar of raw SQL fields, or an array reference of
1817 field names, and adds on an SQL C<RETURNING> statement at the end.
1818 This allows you to return data generated by the insert statement
1819 (such as row IDs) without performing another C<SELECT> statement.
1820 Note, however, this is not part of the SQL standard and may not
1821 be supported by all database engines.
1825 =head2 update($table, \%fieldvals, \%where, \%options)
1827 This takes a table, hashref of field/value pairs, and an optional
1828 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1830 See the sections on L</"Inserting and Updating Arrays"> and
1831 L</"Inserting and Updating SQL"> for information on how to insert
1832 with those data types.
1834 The optional C<\%options> hash reference may contain additional
1835 options to generate the update SQL. Currently supported options
1842 See the C<returning> option to
1843 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1847 =head2 select($source, $fields, $where, $order)
1849 This returns a SQL SELECT statement and associated list of bind values, as
1850 specified by the arguments:
1856 Specification of the 'FROM' part of the statement.
1857 The argument can be either a plain scalar (interpreted as a table
1858 name, will be quoted), or an arrayref (interpreted as a list
1859 of table names, joined by commas, quoted), or a scalarref
1860 (literal SQL, not quoted).
1864 Specification of the list of fields to retrieve from
1866 The argument can be either an arrayref (interpreted as a list
1867 of field names, will be joined by commas and quoted), or a
1868 plain scalar (literal SQL, not quoted).
1869 Please observe that this API is not as flexible as that of
1870 the first argument C<$source>, for backwards compatibility reasons.
1874 Optional argument to specify the WHERE part of the query.
1875 The argument is most often a hashref, but can also be
1876 an arrayref or plain scalar --
1877 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1881 Optional argument to specify the ORDER BY part of the query.
1882 The argument can be a scalar, a hashref or an arrayref
1883 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1889 =head2 delete($table, \%where, \%options)
1891 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1892 It returns an SQL DELETE statement and list of bind values.
1894 The optional C<\%options> hash reference may contain additional
1895 options to generate the delete SQL. Currently supported options
1902 See the C<returning> option to
1903 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1907 =head2 where(\%where, $order)
1909 This is used to generate just the WHERE clause. For example,
1910 if you have an arbitrary data structure and know what the
1911 rest of your SQL is going to look like, but want an easy way
1912 to produce a WHERE clause, use this. It returns an SQL WHERE
1913 clause and list of bind values.
1916 =head2 values(\%data)
1918 This just returns the values from the hash C<%data>, in the same
1919 order that would be returned from any of the other above queries.
1920 Using this allows you to markedly speed up your queries if you
1921 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1923 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1925 Warning: This is an experimental method and subject to change.
1927 This returns arbitrarily generated SQL. It's a really basic shortcut.
1928 It will return two different things, depending on return context:
1930 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1931 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1933 These would return the following:
1935 # First calling form
1936 $stmt = "CREATE TABLE test (?, ?)";
1937 @bind = (field1, field2);
1939 # Second calling form
1940 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1942 Depending on what you're trying to do, it's up to you to choose the correct
1943 format. In this example, the second form is what you would want.
1947 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1951 ALTER SESSION SET nls_date_format = 'MM/YY'
1953 You get the idea. Strings get their case twiddled, but everything
1954 else remains verbatim.
1956 =head1 EXPORTABLE FUNCTIONS
1958 =head2 is_plain_value
1960 Determines if the supplied argument is a plain value as understood by this
1965 =item * The value is C<undef>
1967 =item * The value is a non-reference
1969 =item * The value is an object with stringification overloading
1971 =item * The value is of the form C<< { -value => $anything } >>
1975 On failure returns C<undef>, on success returns a B<scalar> reference
1976 to the original supplied argument.
1982 The stringification overloading detection is rather advanced: it takes
1983 into consideration not only the presence of a C<""> overload, but if that
1984 fails also checks for enabled
1985 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1986 on either C<0+> or C<bool>.
1988 Unfortunately testing in the field indicates that this
1989 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1990 but only when very large numbers of stringifying objects are involved.
1991 At the time of writing ( Sep 2014 ) there is no clear explanation of
1992 the direct cause, nor is there a manageably small test case that reliably
1993 reproduces the problem.
1995 If you encounter any of the following exceptions in B<random places within
1996 your application stack> - this module may be to blame:
1998 Operation "ne": no method found,
1999 left argument in overloaded package <something>,
2000 right argument in overloaded package <something>
2004 Stub found while resolving method "???" overloading """" in package <something>
2006 If you fall victim to the above - please attempt to reduce the problem
2007 to something that could be sent to the L<SQL::Abstract developers
2008 |DBIx::Class/GETTING HELP/SUPPORT>
2009 (either publicly or privately). As a workaround in the meantime you can
2010 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2011 value, which will most likely eliminate your problem (at the expense of
2012 not being able to properly detect exotic forms of stringification).
2014 This notice and environment variable will be removed in a future version,
2015 as soon as the underlying problem is found and a reliable workaround is
2020 =head2 is_literal_value
2022 Determines if the supplied argument is a literal value as understood by this
2027 =item * C<\$sql_string>
2029 =item * C<\[ $sql_string, @bind_values ]>
2033 On failure returns C<undef>, on success returns an B<array> reference
2034 containing the unpacked version of the supplied literal SQL and bind values.
2036 =head1 WHERE CLAUSES
2040 This module uses a variation on the idea from L<DBIx::Abstract>. It
2041 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2042 module is that things in arrays are OR'ed, and things in hashes
2045 The easiest way to explain is to show lots of examples. After
2046 each C<%where> hash shown, it is assumed you used:
2048 my($stmt, @bind) = $sql->where(\%where);
2050 However, note that the C<%where> hash can be used directly in any
2051 of the other functions as well, as described above.
2053 =head2 Key-value pairs
2055 So, let's get started. To begin, a simple hash:
2059 status => 'completed'
2062 Is converted to SQL C<key = val> statements:
2064 $stmt = "WHERE user = ? AND status = ?";
2065 @bind = ('nwiger', 'completed');
2067 One common thing I end up doing is having a list of values that
2068 a field can be in. To do this, simply specify a list inside of
2073 status => ['assigned', 'in-progress', 'pending'];
2076 This simple code will create the following:
2078 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2079 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2081 A field associated to an empty arrayref will be considered a
2082 logical false and will generate 0=1.
2084 =head2 Tests for NULL values
2086 If the value part is C<undef> then this is converted to SQL <IS NULL>
2095 $stmt = "WHERE user = ? AND status IS NULL";
2098 To test if a column IS NOT NULL:
2102 status => { '!=', undef },
2105 =head2 Specific comparison operators
2107 If you want to specify a different type of operator for your comparison,
2108 you can use a hashref for a given column:
2112 status => { '!=', 'completed' }
2115 Which would generate:
2117 $stmt = "WHERE user = ? AND status != ?";
2118 @bind = ('nwiger', 'completed');
2120 To test against multiple values, just enclose the values in an arrayref:
2122 status => { '=', ['assigned', 'in-progress', 'pending'] };
2124 Which would give you:
2126 "WHERE status = ? OR status = ? OR status = ?"
2129 The hashref can also contain multiple pairs, in which case it is expanded
2130 into an C<AND> of its elements:
2134 status => { '!=', 'completed', -not_like => 'pending%' }
2137 # Or more dynamically, like from a form
2138 $where{user} = 'nwiger';
2139 $where{status}{'!='} = 'completed';
2140 $where{status}{'-not_like'} = 'pending%';
2142 # Both generate this
2143 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2144 @bind = ('nwiger', 'completed', 'pending%');
2147 To get an OR instead, you can combine it with the arrayref idea:
2151 priority => [ { '=', 2 }, { '>', 5 } ]
2154 Which would generate:
2156 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2157 @bind = ('2', '5', 'nwiger');
2159 If you want to include literal SQL (with or without bind values), just use a
2160 scalar reference or reference to an arrayref as the value:
2163 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2164 date_expires => { '<' => \"now()" }
2167 Which would generate:
2169 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2170 @bind = ('11/26/2008');
2173 =head2 Logic and nesting operators
2175 In the example above,
2176 there is a subtle trap if you want to say something like
2177 this (notice the C<AND>):
2179 WHERE priority != ? AND priority != ?
2181 Because, in Perl you I<can't> do this:
2183 priority => { '!=' => 2, '!=' => 1 }
2185 As the second C<!=> key will obliterate the first. The solution
2186 is to use the special C<-modifier> form inside an arrayref:
2188 priority => [ -and => {'!=', 2},
2192 Normally, these would be joined by C<OR>, but the modifier tells it
2193 to use C<AND> instead. (Hint: You can use this in conjunction with the
2194 C<logic> option to C<new()> in order to change the way your queries
2195 work by default.) B<Important:> Note that the C<-modifier> goes
2196 B<INSIDE> the arrayref, as an extra first element. This will
2197 B<NOT> do what you think it might:
2199 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2201 Here is a quick list of equivalencies, since there is some overlap:
2204 status => {'!=', 'completed', 'not like', 'pending%' }
2205 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2208 status => {'=', ['assigned', 'in-progress']}
2209 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2210 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2214 =head2 Special operators: IN, BETWEEN, etc.
2216 You can also use the hashref format to compare a list of fields using the
2217 C<IN> comparison operator, by specifying the list as an arrayref:
2220 status => 'completed',
2221 reportid => { -in => [567, 2335, 2] }
2224 Which would generate:
2226 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2227 @bind = ('completed', '567', '2335', '2');
2229 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2232 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2233 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2234 'sqltrue' (by default: C<1=1>).
2236 In addition to the array you can supply a chunk of literal sql or
2237 literal sql with bind:
2240 customer => { -in => \[
2241 'SELECT cust_id FROM cust WHERE balance > ?',
2244 status => { -in => \'SELECT status_codes FROM states' },
2250 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2251 AND status IN ( SELECT status_codes FROM states )
2255 Finally, if the argument to C<-in> is not a reference, it will be
2256 treated as a single-element array.
2258 Another pair of operators is C<-between> and C<-not_between>,
2259 used with an arrayref of two values:
2263 completion_date => {
2264 -not_between => ['2002-10-01', '2003-02-06']
2270 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2272 Just like with C<-in> all plausible combinations of literal SQL
2276 start0 => { -between => [ 1, 2 ] },
2277 start1 => { -between => \["? AND ?", 1, 2] },
2278 start2 => { -between => \"lower(x) AND upper(y)" },
2279 start3 => { -between => [
2281 \["upper(?)", 'stuff' ],
2288 ( start0 BETWEEN ? AND ? )
2289 AND ( start1 BETWEEN ? AND ? )
2290 AND ( start2 BETWEEN lower(x) AND upper(y) )
2291 AND ( start3 BETWEEN lower(x) AND upper(?) )
2293 @bind = (1, 2, 1, 2, 'stuff');
2296 These are the two builtin "special operators"; but the
2297 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2299 =head2 Unary operators: bool
2301 If you wish to test against boolean columns or functions within your
2302 database you can use the C<-bool> and C<-not_bool> operators. For
2303 example to test the column C<is_user> being true and the column
2304 C<is_enabled> being false you would use:-
2308 -not_bool => 'is_enabled',
2313 WHERE is_user AND NOT is_enabled
2315 If a more complex combination is required, testing more conditions,
2316 then you should use the and/or operators:-
2321 -not_bool => { two=> { -rlike => 'bar' } },
2322 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2333 (NOT ( three = ? OR three > ? ))
2336 =head2 Nested conditions, -and/-or prefixes
2338 So far, we've seen how multiple conditions are joined with a top-level
2339 C<AND>. We can change this by putting the different conditions we want in
2340 hashes and then putting those hashes in an array. For example:
2345 status => { -like => ['pending%', 'dispatched'] },
2349 status => 'unassigned',
2353 This data structure would create the following:
2355 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2356 OR ( user = ? AND status = ? ) )";
2357 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2360 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2361 to change the logic inside:
2367 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2368 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2375 $stmt = "WHERE ( user = ?
2376 AND ( ( workhrs > ? AND geo = ? )
2377 OR ( workhrs < ? OR geo = ? ) ) )";
2378 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2380 =head3 Algebraic inconsistency, for historical reasons
2382 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2383 operator goes C<outside> of the nested structure; whereas when connecting
2384 several constraints on one column, the C<-and> operator goes
2385 C<inside> the arrayref. Here is an example combining both features:
2388 -and => [a => 1, b => 2],
2389 -or => [c => 3, d => 4],
2390 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2395 WHERE ( ( ( a = ? AND b = ? )
2396 OR ( c = ? OR d = ? )
2397 OR ( e LIKE ? AND e LIKE ? ) ) )
2399 This difference in syntax is unfortunate but must be preserved for
2400 historical reasons. So be careful: the two examples below would
2401 seem algebraically equivalent, but they are not
2404 { -like => 'foo%' },
2405 { -like => '%bar' },
2407 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2410 { col => { -like => 'foo%' } },
2411 { col => { -like => '%bar' } },
2413 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2416 =head2 Literal SQL and value type operators
2418 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2419 side" is a column name and the "right side" is a value (normally rendered as
2420 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2421 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2422 alter this behavior. There are several ways of doing so.
2426 This is a virtual operator that signals the string to its right side is an
2427 identifier (a column name) and not a value. For example to compare two
2428 columns you would write:
2431 priority => { '<', 2 },
2432 requestor => { -ident => 'submitter' },
2437 $stmt = "WHERE priority < ? AND requestor = submitter";
2440 If you are maintaining legacy code you may see a different construct as
2441 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2446 This is a virtual operator that signals that the construct to its right side
2447 is a value to be passed to DBI. This is for example necessary when you want
2448 to write a where clause against an array (for RDBMS that support such
2449 datatypes). For example:
2452 array => { -value => [1, 2, 3] }
2457 $stmt = 'WHERE array = ?';
2458 @bind = ([1, 2, 3]);
2460 Note that if you were to simply say:
2466 the result would probably not be what you wanted:
2468 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2473 Finally, sometimes only literal SQL will do. To include a random snippet
2474 of SQL verbatim, you specify it as a scalar reference. Consider this only
2475 as a last resort. Usually there is a better way. For example:
2478 priority => { '<', 2 },
2479 requestor => { -in => \'(SELECT name FROM hitmen)' },
2484 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2487 Note that in this example, you only get one bind parameter back, since
2488 the verbatim SQL is passed as part of the statement.
2492 Never use untrusted input as a literal SQL argument - this is a massive
2493 security risk (there is no way to check literal snippets for SQL
2494 injections and other nastyness). If you need to deal with untrusted input
2495 use literal SQL with placeholders as described next.
2497 =head3 Literal SQL with placeholders and bind values (subqueries)
2499 If the literal SQL to be inserted has placeholders and bind values,
2500 use a reference to an arrayref (yes this is a double reference --
2501 not so common, but perfectly legal Perl). For example, to find a date
2502 in Postgres you can use something like this:
2505 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2510 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2513 Note that you must pass the bind values in the same format as they are returned
2514 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2515 to C<columns>, you must provide the bind values in the
2516 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2517 scalar value; most commonly the column name, but you can use any scalar value
2518 (including references and blessed references), L<SQL::Abstract> will simply
2519 pass it through intact. So if C<bindtype> is set to C<columns> the above
2520 example will look like:
2523 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2526 Literal SQL is especially useful for nesting parenthesized clauses in the
2527 main SQL query. Here is a first example:
2529 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2533 bar => \["IN ($sub_stmt)" => @sub_bind],
2538 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2539 WHERE c2 < ? AND c3 LIKE ?))";
2540 @bind = (1234, 100, "foo%");
2542 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2543 are expressed in the same way. Of course the C<$sub_stmt> and
2544 its associated bind values can be generated through a former call
2547 my ($sub_stmt, @sub_bind)
2548 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2549 c3 => {-like => "foo%"}});
2552 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2555 In the examples above, the subquery was used as an operator on a column;
2556 but the same principle also applies for a clause within the main C<%where>
2557 hash, like an EXISTS subquery:
2559 my ($sub_stmt, @sub_bind)
2560 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2561 my %where = ( -and => [
2563 \["EXISTS ($sub_stmt)" => @sub_bind],
2568 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2569 WHERE c1 = ? AND c2 > t0.c0))";
2573 Observe that the condition on C<c2> in the subquery refers to
2574 column C<t0.c0> of the main query: this is I<not> a bind
2575 value, so we have to express it through a scalar ref.
2576 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2577 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2578 what we wanted here.
2580 Finally, here is an example where a subquery is used
2581 for expressing unary negation:
2583 my ($sub_stmt, @sub_bind)
2584 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2585 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2587 lname => {like => '%son%'},
2588 \["NOT ($sub_stmt)" => @sub_bind],
2593 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2594 @bind = ('%son%', 10, 20)
2596 =head3 Deprecated usage of Literal SQL
2598 Below are some examples of archaic use of literal SQL. It is shown only as
2599 reference for those who deal with legacy code. Each example has a much
2600 better, cleaner and safer alternative that users should opt for in new code.
2606 my %where = ( requestor => \'IS NOT NULL' )
2608 $stmt = "WHERE requestor IS NOT NULL"
2610 This used to be the way of generating NULL comparisons, before the handling
2611 of C<undef> got formalized. For new code please use the superior syntax as
2612 described in L</Tests for NULL values>.
2616 my %where = ( requestor => \'= submitter' )
2618 $stmt = "WHERE requestor = submitter"
2620 This used to be the only way to compare columns. Use the superior L</-ident>
2621 method for all new code. For example an identifier declared in such a way
2622 will be properly quoted if L</quote_char> is properly set, while the legacy
2623 form will remain as supplied.
2627 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2629 $stmt = "WHERE completed > ? AND is_ready"
2630 @bind = ('2012-12-21')
2632 Using an empty string literal used to be the only way to express a boolean.
2633 For all new code please use the much more readable
2634 L<-bool|/Unary operators: bool> operator.
2640 These pages could go on for a while, since the nesting of the data
2641 structures this module can handle are pretty much unlimited (the
2642 module implements the C<WHERE> expansion as a recursive function
2643 internally). Your best bet is to "play around" with the module a
2644 little to see how the data structures behave, and choose the best
2645 format for your data based on that.
2647 And of course, all the values above will probably be replaced with
2648 variables gotten from forms or the command line. After all, if you
2649 knew everything ahead of time, you wouldn't have to worry about
2650 dynamically-generating SQL and could just hardwire it into your
2653 =head1 ORDER BY CLAUSES
2655 Some functions take an order by clause. This can either be a scalar (just a
2656 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2657 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2660 Given | Will Generate
2661 ---------------------------------------------------------------
2663 'colA' | ORDER BY colA
2665 [qw/colA colB/] | ORDER BY colA, colB
2667 {-asc => 'colA'} | ORDER BY colA ASC
2669 {-desc => 'colB'} | ORDER BY colB DESC
2671 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2673 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2675 \'colA DESC' | ORDER BY colA DESC
2677 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2678 | /* ...with $x bound to ? */
2681 { -asc => 'colA' }, | colA ASC,
2682 { -desc => [qw/colB/] }, | colB DESC,
2683 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2684 \'colE DESC', | colE DESC,
2685 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2686 ] | /* ...with $x bound to ? */
2687 ===============================================================
2691 =head1 SPECIAL OPERATORS
2693 my $sqlmaker = SQL::Abstract->new(special_ops => [
2697 my ($self, $field, $op, $arg) = @_;
2703 handler => 'method_name',
2707 A "special operator" is a SQL syntactic clause that can be
2708 applied to a field, instead of a usual binary operator.
2711 WHERE field IN (?, ?, ?)
2712 WHERE field BETWEEN ? AND ?
2713 WHERE MATCH(field) AGAINST (?, ?)
2715 Special operators IN and BETWEEN are fairly standard and therefore
2716 are builtin within C<SQL::Abstract> (as the overridable methods
2717 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2718 like the MATCH .. AGAINST example above which is specific to MySQL,
2719 you can write your own operator handlers - supply a C<special_ops>
2720 argument to the C<new> method. That argument takes an arrayref of
2721 operator definitions; each operator definition is a hashref with two
2728 the regular expression to match the operator
2732 Either a coderef or a plain scalar method name. In both cases
2733 the expected return is C<< ($sql, @bind) >>.
2735 When supplied with a method name, it is simply called on the
2736 L<SQL::Abstract> object as:
2738 $self->$method_name($field, $op, $arg)
2742 $field is the LHS of the operator
2743 $op is the part that matched the handler regex
2746 When supplied with a coderef, it is called as:
2748 $coderef->($self, $field, $op, $arg)
2753 For example, here is an implementation
2754 of the MATCH .. AGAINST syntax for MySQL
2756 my $sqlmaker = SQL::Abstract->new(special_ops => [
2758 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2759 {regex => qr/^match$/i,
2761 my ($self, $field, $op, $arg) = @_;
2762 $arg = [$arg] if not ref $arg;
2763 my $label = $self->_quote($field);
2764 my ($placeholder) = $self->_convert('?');
2765 my $placeholders = join ", ", (($placeholder) x @$arg);
2766 my $sql = $self->_sqlcase('match') . " ($label) "
2767 . $self->_sqlcase('against') . " ($placeholders) ";
2768 my @bind = $self->_bindtype($field, @$arg);
2769 return ($sql, @bind);
2776 =head1 UNARY OPERATORS
2778 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2782 my ($self, $op, $arg) = @_;
2788 handler => 'method_name',
2792 A "unary operator" is a SQL syntactic clause that can be
2793 applied to a field - the operator goes before the field
2795 You can write your own operator handlers - supply a C<unary_ops>
2796 argument to the C<new> method. That argument takes an arrayref of
2797 operator definitions; each operator definition is a hashref with two
2804 the regular expression to match the operator
2808 Either a coderef or a plain scalar method name. In both cases
2809 the expected return is C<< $sql >>.
2811 When supplied with a method name, it is simply called on the
2812 L<SQL::Abstract> object as:
2814 $self->$method_name($op, $arg)
2818 $op is the part that matched the handler regex
2819 $arg is the RHS or argument of the operator
2821 When supplied with a coderef, it is called as:
2823 $coderef->($self, $op, $arg)
2831 Thanks to some benchmarking by Mark Stosberg, it turns out that
2832 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2833 I must admit this wasn't an intentional design issue, but it's a
2834 byproduct of the fact that you get to control your C<DBI> handles
2837 To maximize performance, use a code snippet like the following:
2839 # prepare a statement handle using the first row
2840 # and then reuse it for the rest of the rows
2842 for my $href (@array_of_hashrefs) {
2843 $stmt ||= $sql->insert('table', $href);
2844 $sth ||= $dbh->prepare($stmt);
2845 $sth->execute($sql->values($href));
2848 The reason this works is because the keys in your C<$href> are sorted
2849 internally by B<SQL::Abstract>. Thus, as long as your data retains
2850 the same structure, you only have to generate the SQL the first time
2851 around. On subsequent queries, simply use the C<values> function provided
2852 by this module to return your values in the correct order.
2854 However this depends on the values having the same type - if, for
2855 example, the values of a where clause may either have values
2856 (resulting in sql of the form C<column = ?> with a single bind
2857 value), or alternatively the values might be C<undef> (resulting in
2858 sql of the form C<column IS NULL> with no bind value) then the
2859 caching technique suggested will not work.
2863 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2864 really like this part (I do, at least). Building up a complex query
2865 can be as simple as the following:
2872 use CGI::FormBuilder;
2875 my $form = CGI::FormBuilder->new(...);
2876 my $sql = SQL::Abstract->new;
2878 if ($form->submitted) {
2879 my $field = $form->field;
2880 my $id = delete $field->{id};
2881 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2884 Of course, you would still have to connect using C<DBI> to run the
2885 query, but the point is that if you make your form look like your
2886 table, the actual query script can be extremely simplistic.
2888 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2889 a fast interface to returning and formatting data. I frequently
2890 use these three modules together to write complex database query
2891 apps in under 50 lines.
2893 =head1 HOW TO CONTRIBUTE
2895 Contributions are always welcome, in all usable forms (we especially
2896 welcome documentation improvements). The delivery methods include git-
2897 or unified-diff formatted patches, GitHub pull requests, or plain bug
2898 reports either via RT or the Mailing list. Contributors are generally
2899 granted full access to the official repository after their first several
2900 patches pass successful review.
2902 This project is maintained in a git repository. The code and related tools are
2903 accessible at the following locations:
2907 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2909 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2911 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2913 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2919 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2920 Great care has been taken to preserve the I<published> behavior
2921 documented in previous versions in the 1.* family; however,
2922 some features that were previously undocumented, or behaved
2923 differently from the documentation, had to be changed in order
2924 to clarify the semantics. Hence, client code that was relying
2925 on some dark areas of C<SQL::Abstract> v1.*
2926 B<might behave differently> in v1.50.
2928 The main changes are:
2934 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2938 support for the { operator => \"..." } construct (to embed literal SQL)
2942 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2946 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2950 defensive programming: check arguments
2954 fixed bug with global logic, which was previously implemented
2955 through global variables yielding side-effects. Prior versions would
2956 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2957 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2958 Now this is interpreted
2959 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2964 fixed semantics of _bindtype on array args
2968 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2969 we just avoid shifting arrays within that tree.
2973 dropped the C<_modlogic> function
2977 =head1 ACKNOWLEDGEMENTS
2979 There are a number of individuals that have really helped out with
2980 this module. Unfortunately, most of them submitted bugs via CPAN
2981 so I have no idea who they are! But the people I do know are:
2983 Ash Berlin (order_by hash term support)
2984 Matt Trout (DBIx::Class support)
2985 Mark Stosberg (benchmarking)
2986 Chas Owens (initial "IN" operator support)
2987 Philip Collins (per-field SQL functions)
2988 Eric Kolve (hashref "AND" support)
2989 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2990 Dan Kubb (support for "quote_char" and "name_sep")
2991 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2992 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2993 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2994 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2995 Oliver Charles (support for "RETURNING" after "INSERT")
3001 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3005 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3007 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3009 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3010 While not an official support venue, C<DBIx::Class> makes heavy use of
3011 C<SQL::Abstract>, and as such list members there are very familiar with
3012 how to create queries.
3016 This module is free software; you may copy this under the same
3017 terms as perl itself (either the GNU General Public License or
3018 the Artistic License)