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, $expr) = @_;
1053 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1054 foreach my $arg (@to_expand) {
1058 and grep /^-(asc|desc)$/, keys %$arg
1060 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1063 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1064 map $self->_expand_expr($_, undef, -ident), @to_expand;
1065 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1068 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1069 sub { shift->$expander(asc => @_) },
1070 sub { shift->$expander(desc => @_) },
1073 my $expanded = $self->$expander(undef, $arg);
1075 my ($sql, @bind) = $self->_render_expr($expanded);
1077 my $final_sql = $self->_sqlcase(' order by ').$sql;
1079 return wantarray ? ($final_sql, @bind) : $final_sql;
1082 #======================================================================
1083 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1084 #======================================================================
1089 ($self->_render_expr(
1090 $self->_expand_maybe_list_expr($from, undef, -ident)
1095 #======================================================================
1097 #======================================================================
1099 sub _expand_maybe_list_expr {
1100 my ($self, $expr, $logic, $default) = @_;
1102 if (ref($expr) eq 'ARRAY') {
1104 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1111 return $self->_expand_expr($e, $logic, $default);
1114 # highly optimized, as it's called way too often
1116 # my ($self, $label) = @_;
1118 return '' unless defined $_[1];
1119 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1120 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1122 unless ($_[0]->{quote_char}) {
1123 if (ref($_[1]) eq 'ARRAY') {
1124 return join($_[0]->{name_sep}||'.', @{$_[1]});
1126 $_[0]->_assert_pass_injection_guard($_[1]);
1131 my $qref = ref $_[0]->{quote_char};
1133 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1134 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1135 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1137 my $esc = $_[0]->{escape_char} || $r;
1139 # parts containing * are naturally unquoted
1141 $_[0]->{name_sep}||'',
1145 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1147 (ref($_[1]) eq 'ARRAY'
1151 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1159 # Conversion, if applicable
1161 #my ($self, $arg) = @_;
1162 if ($_[0]->{convert_where}) {
1163 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1170 #my ($self, $col, @vals) = @_;
1171 # called often - tighten code
1172 return $_[0]->{bindtype} eq 'columns'
1173 ? map {[$_[1], $_]} @_[2 .. $#_]
1178 # Dies if any element of @bind is not in [colname => value] format
1179 # if bindtype is 'columns'.
1180 sub _assert_bindval_matches_bindtype {
1181 # my ($self, @bind) = @_;
1183 if ($self->{bindtype} eq 'columns') {
1185 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1186 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1192 sub _join_sql_clauses {
1193 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1195 if (@$clauses_aref > 1) {
1196 my $join = " " . $self->_sqlcase($logic) . " ";
1197 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1198 return ($sql, @$bind_aref);
1200 elsif (@$clauses_aref) {
1201 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1204 return (); # if no SQL, ignore @$bind_aref
1209 # Fix SQL case, if so requested
1211 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1212 # don't touch the argument ... crooked logic, but let's not change it!
1213 return $_[0]->{case} ? $_[1] : uc($_[1]);
1217 #======================================================================
1218 # DISPATCHING FROM REFKIND
1219 #======================================================================
1222 my ($self, $data) = @_;
1224 return 'UNDEF' unless defined $data;
1226 # blessed objects are treated like scalars
1227 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1229 return 'SCALAR' unless $ref;
1232 while ($ref eq 'REF') {
1234 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1238 return ($ref||'SCALAR') . ('REF' x $n_steps);
1242 my ($self, $data) = @_;
1243 my @try = ($self->_refkind($data));
1244 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1245 push @try, 'FALLBACK';
1249 sub _METHOD_FOR_refkind {
1250 my ($self, $meth_prefix, $data) = @_;
1253 for (@{$self->_try_refkind($data)}) {
1254 $method = $self->can($meth_prefix."_".$_)
1258 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1262 sub _SWITCH_refkind {
1263 my ($self, $data, $dispatch_table) = @_;
1266 for (@{$self->_try_refkind($data)}) {
1267 $coderef = $dispatch_table->{$_}
1271 puke "no dispatch entry for ".$self->_refkind($data)
1280 #======================================================================
1281 # VALUES, GENERATE, AUTOLOAD
1282 #======================================================================
1284 # LDNOTE: original code from nwiger, didn't touch code in that section
1285 # I feel the AUTOLOAD stuff should not be the default, it should
1286 # only be activated on explicit demand by user.
1290 my $data = shift || return;
1291 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1292 unless ref $data eq 'HASH';
1295 foreach my $k (sort keys %$data) {
1296 my $v = $data->{$k};
1297 $self->_SWITCH_refkind($v, {
1299 if ($self->{array_datatypes}) { # array datatype
1300 push @all_bind, $self->_bindtype($k, $v);
1302 else { # literal SQL with bind
1303 my ($sql, @bind) = @$v;
1304 $self->_assert_bindval_matches_bindtype(@bind);
1305 push @all_bind, @bind;
1308 ARRAYREFREF => sub { # literal SQL with bind
1309 my ($sql, @bind) = @${$v};
1310 $self->_assert_bindval_matches_bindtype(@bind);
1311 push @all_bind, @bind;
1313 SCALARREF => sub { # literal SQL without bind
1315 SCALAR_or_UNDEF => sub {
1316 push @all_bind, $self->_bindtype($k, $v);
1327 my(@sql, @sqlq, @sqlv);
1331 if ($ref eq 'HASH') {
1332 for my $k (sort keys %$_) {
1335 my $label = $self->_quote($k);
1336 if ($r eq 'ARRAY') {
1337 # literal SQL with bind
1338 my ($sql, @bind) = @$v;
1339 $self->_assert_bindval_matches_bindtype(@bind);
1340 push @sqlq, "$label = $sql";
1342 } elsif ($r eq 'SCALAR') {
1343 # literal SQL without bind
1344 push @sqlq, "$label = $$v";
1346 push @sqlq, "$label = ?";
1347 push @sqlv, $self->_bindtype($k, $v);
1350 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1351 } elsif ($ref eq 'ARRAY') {
1352 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1355 if ($r eq 'ARRAY') { # literal SQL with bind
1356 my ($sql, @bind) = @$v;
1357 $self->_assert_bindval_matches_bindtype(@bind);
1360 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1361 # embedded literal SQL
1368 push @sql, '(' . join(', ', @sqlq) . ')';
1369 } elsif ($ref eq 'SCALAR') {
1373 # strings get case twiddled
1374 push @sql, $self->_sqlcase($_);
1378 my $sql = join ' ', @sql;
1380 # this is pretty tricky
1381 # if ask for an array, return ($stmt, @bind)
1382 # otherwise, s/?/shift @sqlv/ to put it inline
1384 return ($sql, @sqlv);
1386 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1387 ref $d ? $d->[1] : $d/e;
1396 # This allows us to check for a local, then _form, attr
1398 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1399 return $self->generate($name, @_);
1410 SQL::Abstract - Generate SQL from Perl data structures
1416 my $sql = SQL::Abstract->new;
1418 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1420 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1422 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1424 my($stmt, @bind) = $sql->delete($table, \%where);
1426 # Then, use these in your DBI statements
1427 my $sth = $dbh->prepare($stmt);
1428 $sth->execute(@bind);
1430 # Just generate the WHERE clause
1431 my($stmt, @bind) = $sql->where(\%where, $order);
1433 # Return values in the same order, for hashed queries
1434 # See PERFORMANCE section for more details
1435 my @bind = $sql->values(\%fieldvals);
1439 This module was inspired by the excellent L<DBIx::Abstract>.
1440 However, in using that module I found that what I really wanted
1441 to do was generate SQL, but still retain complete control over my
1442 statement handles and use the DBI interface. So, I set out to
1443 create an abstract SQL generation module.
1445 While based on the concepts used by L<DBIx::Abstract>, there are
1446 several important differences, especially when it comes to WHERE
1447 clauses. I have modified the concepts used to make the SQL easier
1448 to generate from Perl data structures and, IMO, more intuitive.
1449 The underlying idea is for this module to do what you mean, based
1450 on the data structures you provide it. The big advantage is that
1451 you don't have to modify your code every time your data changes,
1452 as this module figures it out.
1454 To begin with, an SQL INSERT is as easy as just specifying a hash
1455 of C<key=value> pairs:
1458 name => 'Jimbo Bobson',
1459 phone => '123-456-7890',
1460 address => '42 Sister Lane',
1461 city => 'St. Louis',
1462 state => 'Louisiana',
1465 The SQL can then be generated with this:
1467 my($stmt, @bind) = $sql->insert('people', \%data);
1469 Which would give you something like this:
1471 $stmt = "INSERT INTO people
1472 (address, city, name, phone, state)
1473 VALUES (?, ?, ?, ?, ?)";
1474 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1475 '123-456-7890', 'Louisiana');
1477 These are then used directly in your DBI code:
1479 my $sth = $dbh->prepare($stmt);
1480 $sth->execute(@bind);
1482 =head2 Inserting and Updating Arrays
1484 If your database has array types (like for example Postgres),
1485 activate the special option C<< array_datatypes => 1 >>
1486 when creating the C<SQL::Abstract> object.
1487 Then you may use an arrayref to insert and update database array types:
1489 my $sql = SQL::Abstract->new(array_datatypes => 1);
1491 planets => [qw/Mercury Venus Earth Mars/]
1494 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1498 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1500 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1503 =head2 Inserting and Updating SQL
1505 In order to apply SQL functions to elements of your C<%data> you may
1506 specify a reference to an arrayref for the given hash value. For example,
1507 if you need to execute the Oracle C<to_date> function on a value, you can
1508 say something like this:
1512 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1515 The first value in the array is the actual SQL. Any other values are
1516 optional and would be included in the bind values array. This gives
1519 my($stmt, @bind) = $sql->insert('people', \%data);
1521 $stmt = "INSERT INTO people (name, date_entered)
1522 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1523 @bind = ('Bill', '03/02/2003');
1525 An UPDATE is just as easy, all you change is the name of the function:
1527 my($stmt, @bind) = $sql->update('people', \%data);
1529 Notice that your C<%data> isn't touched; the module will generate
1530 the appropriately quirky SQL for you automatically. Usually you'll
1531 want to specify a WHERE clause for your UPDATE, though, which is
1532 where handling C<%where> hashes comes in handy...
1534 =head2 Complex where statements
1536 This module can generate pretty complicated WHERE statements
1537 easily. For example, simple C<key=value> pairs are taken to mean
1538 equality, and if you want to see if a field is within a set
1539 of values, you can use an arrayref. Let's say we wanted to
1540 SELECT some data based on this criteria:
1543 requestor => 'inna',
1544 worker => ['nwiger', 'rcwe', 'sfz'],
1545 status => { '!=', 'completed' }
1548 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1550 The above would give you something like this:
1552 $stmt = "SELECT * FROM tickets WHERE
1553 ( requestor = ? ) AND ( status != ? )
1554 AND ( worker = ? OR worker = ? OR worker = ? )";
1555 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1557 Which you could then use in DBI code like so:
1559 my $sth = $dbh->prepare($stmt);
1560 $sth->execute(@bind);
1566 The methods are simple. There's one for every major SQL operation,
1567 and a constructor you use first. The arguments are specified in a
1568 similar order for each method (table, then fields, then a where
1569 clause) to try and simplify things.
1571 =head2 new(option => 'value')
1573 The C<new()> function takes a list of options and values, and returns
1574 a new B<SQL::Abstract> object which can then be used to generate SQL
1575 through the methods below. The options accepted are:
1581 If set to 'lower', then SQL will be generated in all lowercase. By
1582 default SQL is generated in "textbook" case meaning something like:
1584 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1586 Any setting other than 'lower' is ignored.
1590 This determines what the default comparison operator is. By default
1591 it is C<=>, meaning that a hash like this:
1593 %where = (name => 'nwiger', email => 'nate@wiger.org');
1595 Will generate SQL like this:
1597 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1599 However, you may want loose comparisons by default, so if you set
1600 C<cmp> to C<like> you would get SQL such as:
1602 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1604 You can also override the comparison on an individual basis - see
1605 the huge section on L</"WHERE CLAUSES"> at the bottom.
1607 =item sqltrue, sqlfalse
1609 Expressions for inserting boolean values within SQL statements.
1610 By default these are C<1=1> and C<1=0>. They are used
1611 by the special operators C<-in> and C<-not_in> for generating
1612 correct SQL even when the argument is an empty array (see below).
1616 This determines the default logical operator for multiple WHERE
1617 statements in arrays or hashes. If absent, the default logic is "or"
1618 for arrays, and "and" for hashes. This means that a WHERE
1622 event_date => {'>=', '2/13/99'},
1623 event_date => {'<=', '4/24/03'},
1626 will generate SQL like this:
1628 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1630 This is probably not what you want given this query, though (look
1631 at the dates). To change the "OR" to an "AND", simply specify:
1633 my $sql = SQL::Abstract->new(logic => 'and');
1635 Which will change the above C<WHERE> to:
1637 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1639 The logic can also be changed locally by inserting
1640 a modifier in front of an arrayref:
1642 @where = (-and => [event_date => {'>=', '2/13/99'},
1643 event_date => {'<=', '4/24/03'} ]);
1645 See the L</"WHERE CLAUSES"> section for explanations.
1649 This will automatically convert comparisons using the specified SQL
1650 function for both column and value. This is mostly used with an argument
1651 of C<upper> or C<lower>, so that the SQL will have the effect of
1652 case-insensitive "searches". For example, this:
1654 $sql = SQL::Abstract->new(convert => 'upper');
1655 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1657 Will turn out the following SQL:
1659 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1661 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1662 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1663 not validate this option; it will just pass through what you specify verbatim).
1667 This is a kludge because many databases suck. For example, you can't
1668 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1669 Instead, you have to use C<bind_param()>:
1671 $sth->bind_param(1, 'reg data');
1672 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1674 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1675 which loses track of which field each slot refers to. Fear not.
1677 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1678 Currently, you can specify either C<normal> (default) or C<columns>. If you
1679 specify C<columns>, you will get an array that looks like this:
1681 my $sql = SQL::Abstract->new(bindtype => 'columns');
1682 my($stmt, @bind) = $sql->insert(...);
1685 [ 'column1', 'value1' ],
1686 [ 'column2', 'value2' ],
1687 [ 'column3', 'value3' ],
1690 You can then iterate through this manually, using DBI's C<bind_param()>.
1692 $sth->prepare($stmt);
1695 my($col, $data) = @$_;
1696 if ($col eq 'details' || $col eq 'comments') {
1697 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1698 } elsif ($col eq 'image') {
1699 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1701 $sth->bind_param($i, $data);
1705 $sth->execute; # execute without @bind now
1707 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1708 Basically, the advantage is still that you don't have to care which fields
1709 are or are not included. You could wrap that above C<for> loop in a simple
1710 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1711 get a layer of abstraction over manual SQL specification.
1713 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1714 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1715 will expect the bind values in this format.
1719 This is the character that a table or column name will be quoted
1720 with. By default this is an empty string, but you could set it to
1721 the character C<`>, to generate SQL like this:
1723 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1725 Alternatively, you can supply an array ref of two items, the first being the left
1726 hand quote character, and the second the right hand quote character. For
1727 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1728 that generates SQL like this:
1730 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1732 Quoting is useful if you have tables or columns names that are reserved
1733 words in your database's SQL dialect.
1737 This is the character that will be used to escape L</quote_char>s appearing
1738 in an identifier before it has been quoted.
1740 The parameter default in case of a single L</quote_char> character is the quote
1743 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1744 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1745 of the B<opening (left)> L</quote_char> within the identifier are currently left
1746 untouched. The default for opening-closing-style quotes may change in future
1747 versions, thus you are B<strongly encouraged> to specify the escape character
1752 This is the character that separates a table and column name. It is
1753 necessary to specify this when the C<quote_char> option is selected,
1754 so that tables and column names can be individually quoted like this:
1756 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1758 =item injection_guard
1760 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1761 column name specified in a query structure. This is a safety mechanism to avoid
1762 injection attacks when mishandling user input e.g.:
1764 my %condition_as_column_value_pairs = get_values_from_user();
1765 $sqla->select( ... , \%condition_as_column_value_pairs );
1767 If the expression matches an exception is thrown. Note that literal SQL
1768 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1770 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1772 =item array_datatypes
1774 When this option is true, arrayrefs in INSERT or UPDATE are
1775 interpreted as array datatypes and are passed directly
1777 When this option is false, arrayrefs are interpreted
1778 as literal SQL, just like refs to arrayrefs
1779 (but this behavior is for backwards compatibility; when writing
1780 new queries, use the "reference to arrayref" syntax
1786 Takes a reference to a list of "special operators"
1787 to extend the syntax understood by L<SQL::Abstract>.
1788 See section L</"SPECIAL OPERATORS"> for details.
1792 Takes a reference to a list of "unary operators"
1793 to extend the syntax understood by L<SQL::Abstract>.
1794 See section L</"UNARY OPERATORS"> for details.
1800 =head2 insert($table, \@values || \%fieldvals, \%options)
1802 This is the simplest function. You simply give it a table name
1803 and either an arrayref of values or hashref of field/value pairs.
1804 It returns an SQL INSERT statement and a list of bind values.
1805 See the sections on L</"Inserting and Updating Arrays"> and
1806 L</"Inserting and Updating SQL"> for information on how to insert
1807 with those data types.
1809 The optional C<\%options> hash reference may contain additional
1810 options to generate the insert SQL. Currently supported options
1817 Takes either a scalar of raw SQL fields, or an array reference of
1818 field names, and adds on an SQL C<RETURNING> statement at the end.
1819 This allows you to return data generated by the insert statement
1820 (such as row IDs) without performing another C<SELECT> statement.
1821 Note, however, this is not part of the SQL standard and may not
1822 be supported by all database engines.
1826 =head2 update($table, \%fieldvals, \%where, \%options)
1828 This takes a table, hashref of field/value pairs, and an optional
1829 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1831 See the sections on L</"Inserting and Updating Arrays"> and
1832 L</"Inserting and Updating SQL"> for information on how to insert
1833 with those data types.
1835 The optional C<\%options> hash reference may contain additional
1836 options to generate the update SQL. Currently supported options
1843 See the C<returning> option to
1844 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1848 =head2 select($source, $fields, $where, $order)
1850 This returns a SQL SELECT statement and associated list of bind values, as
1851 specified by the arguments:
1857 Specification of the 'FROM' part of the statement.
1858 The argument can be either a plain scalar (interpreted as a table
1859 name, will be quoted), or an arrayref (interpreted as a list
1860 of table names, joined by commas, quoted), or a scalarref
1861 (literal SQL, not quoted).
1865 Specification of the list of fields to retrieve from
1867 The argument can be either an arrayref (interpreted as a list
1868 of field names, will be joined by commas and quoted), or a
1869 plain scalar (literal SQL, not quoted).
1870 Please observe that this API is not as flexible as that of
1871 the first argument C<$source>, for backwards compatibility reasons.
1875 Optional argument to specify the WHERE part of the query.
1876 The argument is most often a hashref, but can also be
1877 an arrayref or plain scalar --
1878 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1882 Optional argument to specify the ORDER BY part of the query.
1883 The argument can be a scalar, a hashref or an arrayref
1884 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1890 =head2 delete($table, \%where, \%options)
1892 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1893 It returns an SQL DELETE statement and list of bind values.
1895 The optional C<\%options> hash reference may contain additional
1896 options to generate the delete SQL. Currently supported options
1903 See the C<returning> option to
1904 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1908 =head2 where(\%where, $order)
1910 This is used to generate just the WHERE clause. For example,
1911 if you have an arbitrary data structure and know what the
1912 rest of your SQL is going to look like, but want an easy way
1913 to produce a WHERE clause, use this. It returns an SQL WHERE
1914 clause and list of bind values.
1917 =head2 values(\%data)
1919 This just returns the values from the hash C<%data>, in the same
1920 order that would be returned from any of the other above queries.
1921 Using this allows you to markedly speed up your queries if you
1922 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1924 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1926 Warning: This is an experimental method and subject to change.
1928 This returns arbitrarily generated SQL. It's a really basic shortcut.
1929 It will return two different things, depending on return context:
1931 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1932 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1934 These would return the following:
1936 # First calling form
1937 $stmt = "CREATE TABLE test (?, ?)";
1938 @bind = (field1, field2);
1940 # Second calling form
1941 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1943 Depending on what you're trying to do, it's up to you to choose the correct
1944 format. In this example, the second form is what you would want.
1948 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1952 ALTER SESSION SET nls_date_format = 'MM/YY'
1954 You get the idea. Strings get their case twiddled, but everything
1955 else remains verbatim.
1957 =head1 EXPORTABLE FUNCTIONS
1959 =head2 is_plain_value
1961 Determines if the supplied argument is a plain value as understood by this
1966 =item * The value is C<undef>
1968 =item * The value is a non-reference
1970 =item * The value is an object with stringification overloading
1972 =item * The value is of the form C<< { -value => $anything } >>
1976 On failure returns C<undef>, on success returns a B<scalar> reference
1977 to the original supplied argument.
1983 The stringification overloading detection is rather advanced: it takes
1984 into consideration not only the presence of a C<""> overload, but if that
1985 fails also checks for enabled
1986 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1987 on either C<0+> or C<bool>.
1989 Unfortunately testing in the field indicates that this
1990 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1991 but only when very large numbers of stringifying objects are involved.
1992 At the time of writing ( Sep 2014 ) there is no clear explanation of
1993 the direct cause, nor is there a manageably small test case that reliably
1994 reproduces the problem.
1996 If you encounter any of the following exceptions in B<random places within
1997 your application stack> - this module may be to blame:
1999 Operation "ne": no method found,
2000 left argument in overloaded package <something>,
2001 right argument in overloaded package <something>
2005 Stub found while resolving method "???" overloading """" in package <something>
2007 If you fall victim to the above - please attempt to reduce the problem
2008 to something that could be sent to the L<SQL::Abstract developers
2009 |DBIx::Class/GETTING HELP/SUPPORT>
2010 (either publicly or privately). As a workaround in the meantime you can
2011 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2012 value, which will most likely eliminate your problem (at the expense of
2013 not being able to properly detect exotic forms of stringification).
2015 This notice and environment variable will be removed in a future version,
2016 as soon as the underlying problem is found and a reliable workaround is
2021 =head2 is_literal_value
2023 Determines if the supplied argument is a literal value as understood by this
2028 =item * C<\$sql_string>
2030 =item * C<\[ $sql_string, @bind_values ]>
2034 On failure returns C<undef>, on success returns an B<array> reference
2035 containing the unpacked version of the supplied literal SQL and bind values.
2037 =head1 WHERE CLAUSES
2041 This module uses a variation on the idea from L<DBIx::Abstract>. It
2042 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2043 module is that things in arrays are OR'ed, and things in hashes
2046 The easiest way to explain is to show lots of examples. After
2047 each C<%where> hash shown, it is assumed you used:
2049 my($stmt, @bind) = $sql->where(\%where);
2051 However, note that the C<%where> hash can be used directly in any
2052 of the other functions as well, as described above.
2054 =head2 Key-value pairs
2056 So, let's get started. To begin, a simple hash:
2060 status => 'completed'
2063 Is converted to SQL C<key = val> statements:
2065 $stmt = "WHERE user = ? AND status = ?";
2066 @bind = ('nwiger', 'completed');
2068 One common thing I end up doing is having a list of values that
2069 a field can be in. To do this, simply specify a list inside of
2074 status => ['assigned', 'in-progress', 'pending'];
2077 This simple code will create the following:
2079 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2080 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2082 A field associated to an empty arrayref will be considered a
2083 logical false and will generate 0=1.
2085 =head2 Tests for NULL values
2087 If the value part is C<undef> then this is converted to SQL <IS NULL>
2096 $stmt = "WHERE user = ? AND status IS NULL";
2099 To test if a column IS NOT NULL:
2103 status => { '!=', undef },
2106 =head2 Specific comparison operators
2108 If you want to specify a different type of operator for your comparison,
2109 you can use a hashref for a given column:
2113 status => { '!=', 'completed' }
2116 Which would generate:
2118 $stmt = "WHERE user = ? AND status != ?";
2119 @bind = ('nwiger', 'completed');
2121 To test against multiple values, just enclose the values in an arrayref:
2123 status => { '=', ['assigned', 'in-progress', 'pending'] };
2125 Which would give you:
2127 "WHERE status = ? OR status = ? OR status = ?"
2130 The hashref can also contain multiple pairs, in which case it is expanded
2131 into an C<AND> of its elements:
2135 status => { '!=', 'completed', -not_like => 'pending%' }
2138 # Or more dynamically, like from a form
2139 $where{user} = 'nwiger';
2140 $where{status}{'!='} = 'completed';
2141 $where{status}{'-not_like'} = 'pending%';
2143 # Both generate this
2144 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2145 @bind = ('nwiger', 'completed', 'pending%');
2148 To get an OR instead, you can combine it with the arrayref idea:
2152 priority => [ { '=', 2 }, { '>', 5 } ]
2155 Which would generate:
2157 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2158 @bind = ('2', '5', 'nwiger');
2160 If you want to include literal SQL (with or without bind values), just use a
2161 scalar reference or reference to an arrayref as the value:
2164 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2165 date_expires => { '<' => \"now()" }
2168 Which would generate:
2170 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2171 @bind = ('11/26/2008');
2174 =head2 Logic and nesting operators
2176 In the example above,
2177 there is a subtle trap if you want to say something like
2178 this (notice the C<AND>):
2180 WHERE priority != ? AND priority != ?
2182 Because, in Perl you I<can't> do this:
2184 priority => { '!=' => 2, '!=' => 1 }
2186 As the second C<!=> key will obliterate the first. The solution
2187 is to use the special C<-modifier> form inside an arrayref:
2189 priority => [ -and => {'!=', 2},
2193 Normally, these would be joined by C<OR>, but the modifier tells it
2194 to use C<AND> instead. (Hint: You can use this in conjunction with the
2195 C<logic> option to C<new()> in order to change the way your queries
2196 work by default.) B<Important:> Note that the C<-modifier> goes
2197 B<INSIDE> the arrayref, as an extra first element. This will
2198 B<NOT> do what you think it might:
2200 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2202 Here is a quick list of equivalencies, since there is some overlap:
2205 status => {'!=', 'completed', 'not like', 'pending%' }
2206 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2209 status => {'=', ['assigned', 'in-progress']}
2210 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2211 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2215 =head2 Special operators: IN, BETWEEN, etc.
2217 You can also use the hashref format to compare a list of fields using the
2218 C<IN> comparison operator, by specifying the list as an arrayref:
2221 status => 'completed',
2222 reportid => { -in => [567, 2335, 2] }
2225 Which would generate:
2227 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2228 @bind = ('completed', '567', '2335', '2');
2230 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2233 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2234 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2235 'sqltrue' (by default: C<1=1>).
2237 In addition to the array you can supply a chunk of literal sql or
2238 literal sql with bind:
2241 customer => { -in => \[
2242 'SELECT cust_id FROM cust WHERE balance > ?',
2245 status => { -in => \'SELECT status_codes FROM states' },
2251 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2252 AND status IN ( SELECT status_codes FROM states )
2256 Finally, if the argument to C<-in> is not a reference, it will be
2257 treated as a single-element array.
2259 Another pair of operators is C<-between> and C<-not_between>,
2260 used with an arrayref of two values:
2264 completion_date => {
2265 -not_between => ['2002-10-01', '2003-02-06']
2271 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2273 Just like with C<-in> all plausible combinations of literal SQL
2277 start0 => { -between => [ 1, 2 ] },
2278 start1 => { -between => \["? AND ?", 1, 2] },
2279 start2 => { -between => \"lower(x) AND upper(y)" },
2280 start3 => { -between => [
2282 \["upper(?)", 'stuff' ],
2289 ( start0 BETWEEN ? AND ? )
2290 AND ( start1 BETWEEN ? AND ? )
2291 AND ( start2 BETWEEN lower(x) AND upper(y) )
2292 AND ( start3 BETWEEN lower(x) AND upper(?) )
2294 @bind = (1, 2, 1, 2, 'stuff');
2297 These are the two builtin "special operators"; but the
2298 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2300 =head2 Unary operators: bool
2302 If you wish to test against boolean columns or functions within your
2303 database you can use the C<-bool> and C<-not_bool> operators. For
2304 example to test the column C<is_user> being true and the column
2305 C<is_enabled> being false you would use:-
2309 -not_bool => 'is_enabled',
2314 WHERE is_user AND NOT is_enabled
2316 If a more complex combination is required, testing more conditions,
2317 then you should use the and/or operators:-
2322 -not_bool => { two=> { -rlike => 'bar' } },
2323 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2334 (NOT ( three = ? OR three > ? ))
2337 =head2 Nested conditions, -and/-or prefixes
2339 So far, we've seen how multiple conditions are joined with a top-level
2340 C<AND>. We can change this by putting the different conditions we want in
2341 hashes and then putting those hashes in an array. For example:
2346 status => { -like => ['pending%', 'dispatched'] },
2350 status => 'unassigned',
2354 This data structure would create the following:
2356 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2357 OR ( user = ? AND status = ? ) )";
2358 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2361 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2362 to change the logic inside:
2368 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2369 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2376 $stmt = "WHERE ( user = ?
2377 AND ( ( workhrs > ? AND geo = ? )
2378 OR ( workhrs < ? OR geo = ? ) ) )";
2379 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2381 =head3 Algebraic inconsistency, for historical reasons
2383 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2384 operator goes C<outside> of the nested structure; whereas when connecting
2385 several constraints on one column, the C<-and> operator goes
2386 C<inside> the arrayref. Here is an example combining both features:
2389 -and => [a => 1, b => 2],
2390 -or => [c => 3, d => 4],
2391 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2396 WHERE ( ( ( a = ? AND b = ? )
2397 OR ( c = ? OR d = ? )
2398 OR ( e LIKE ? AND e LIKE ? ) ) )
2400 This difference in syntax is unfortunate but must be preserved for
2401 historical reasons. So be careful: the two examples below would
2402 seem algebraically equivalent, but they are not
2405 { -like => 'foo%' },
2406 { -like => '%bar' },
2408 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2411 { col => { -like => 'foo%' } },
2412 { col => { -like => '%bar' } },
2414 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2417 =head2 Literal SQL and value type operators
2419 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2420 side" is a column name and the "right side" is a value (normally rendered as
2421 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2422 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2423 alter this behavior. There are several ways of doing so.
2427 This is a virtual operator that signals the string to its right side is an
2428 identifier (a column name) and not a value. For example to compare two
2429 columns you would write:
2432 priority => { '<', 2 },
2433 requestor => { -ident => 'submitter' },
2438 $stmt = "WHERE priority < ? AND requestor = submitter";
2441 If you are maintaining legacy code you may see a different construct as
2442 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2447 This is a virtual operator that signals that the construct to its right side
2448 is a value to be passed to DBI. This is for example necessary when you want
2449 to write a where clause against an array (for RDBMS that support such
2450 datatypes). For example:
2453 array => { -value => [1, 2, 3] }
2458 $stmt = 'WHERE array = ?';
2459 @bind = ([1, 2, 3]);
2461 Note that if you were to simply say:
2467 the result would probably not be what you wanted:
2469 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2474 Finally, sometimes only literal SQL will do. To include a random snippet
2475 of SQL verbatim, you specify it as a scalar reference. Consider this only
2476 as a last resort. Usually there is a better way. For example:
2479 priority => { '<', 2 },
2480 requestor => { -in => \'(SELECT name FROM hitmen)' },
2485 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2488 Note that in this example, you only get one bind parameter back, since
2489 the verbatim SQL is passed as part of the statement.
2493 Never use untrusted input as a literal SQL argument - this is a massive
2494 security risk (there is no way to check literal snippets for SQL
2495 injections and other nastyness). If you need to deal with untrusted input
2496 use literal SQL with placeholders as described next.
2498 =head3 Literal SQL with placeholders and bind values (subqueries)
2500 If the literal SQL to be inserted has placeholders and bind values,
2501 use a reference to an arrayref (yes this is a double reference --
2502 not so common, but perfectly legal Perl). For example, to find a date
2503 in Postgres you can use something like this:
2506 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2511 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2514 Note that you must pass the bind values in the same format as they are returned
2515 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2516 to C<columns>, you must provide the bind values in the
2517 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2518 scalar value; most commonly the column name, but you can use any scalar value
2519 (including references and blessed references), L<SQL::Abstract> will simply
2520 pass it through intact. So if C<bindtype> is set to C<columns> the above
2521 example will look like:
2524 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2527 Literal SQL is especially useful for nesting parenthesized clauses in the
2528 main SQL query. Here is a first example:
2530 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2534 bar => \["IN ($sub_stmt)" => @sub_bind],
2539 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2540 WHERE c2 < ? AND c3 LIKE ?))";
2541 @bind = (1234, 100, "foo%");
2543 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2544 are expressed in the same way. Of course the C<$sub_stmt> and
2545 its associated bind values can be generated through a former call
2548 my ($sub_stmt, @sub_bind)
2549 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2550 c3 => {-like => "foo%"}});
2553 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2556 In the examples above, the subquery was used as an operator on a column;
2557 but the same principle also applies for a clause within the main C<%where>
2558 hash, like an EXISTS subquery:
2560 my ($sub_stmt, @sub_bind)
2561 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2562 my %where = ( -and => [
2564 \["EXISTS ($sub_stmt)" => @sub_bind],
2569 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2570 WHERE c1 = ? AND c2 > t0.c0))";
2574 Observe that the condition on C<c2> in the subquery refers to
2575 column C<t0.c0> of the main query: this is I<not> a bind
2576 value, so we have to express it through a scalar ref.
2577 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2578 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2579 what we wanted here.
2581 Finally, here is an example where a subquery is used
2582 for expressing unary negation:
2584 my ($sub_stmt, @sub_bind)
2585 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2586 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2588 lname => {like => '%son%'},
2589 \["NOT ($sub_stmt)" => @sub_bind],
2594 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2595 @bind = ('%son%', 10, 20)
2597 =head3 Deprecated usage of Literal SQL
2599 Below are some examples of archaic use of literal SQL. It is shown only as
2600 reference for those who deal with legacy code. Each example has a much
2601 better, cleaner and safer alternative that users should opt for in new code.
2607 my %where = ( requestor => \'IS NOT NULL' )
2609 $stmt = "WHERE requestor IS NOT NULL"
2611 This used to be the way of generating NULL comparisons, before the handling
2612 of C<undef> got formalized. For new code please use the superior syntax as
2613 described in L</Tests for NULL values>.
2617 my %where = ( requestor => \'= submitter' )
2619 $stmt = "WHERE requestor = submitter"
2621 This used to be the only way to compare columns. Use the superior L</-ident>
2622 method for all new code. For example an identifier declared in such a way
2623 will be properly quoted if L</quote_char> is properly set, while the legacy
2624 form will remain as supplied.
2628 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2630 $stmt = "WHERE completed > ? AND is_ready"
2631 @bind = ('2012-12-21')
2633 Using an empty string literal used to be the only way to express a boolean.
2634 For all new code please use the much more readable
2635 L<-bool|/Unary operators: bool> operator.
2641 These pages could go on for a while, since the nesting of the data
2642 structures this module can handle are pretty much unlimited (the
2643 module implements the C<WHERE> expansion as a recursive function
2644 internally). Your best bet is to "play around" with the module a
2645 little to see how the data structures behave, and choose the best
2646 format for your data based on that.
2648 And of course, all the values above will probably be replaced with
2649 variables gotten from forms or the command line. After all, if you
2650 knew everything ahead of time, you wouldn't have to worry about
2651 dynamically-generating SQL and could just hardwire it into your
2654 =head1 ORDER BY CLAUSES
2656 Some functions take an order by clause. This can either be a scalar (just a
2657 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2658 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2661 Given | Will Generate
2662 ---------------------------------------------------------------
2664 'colA' | ORDER BY colA
2666 [qw/colA colB/] | ORDER BY colA, colB
2668 {-asc => 'colA'} | ORDER BY colA ASC
2670 {-desc => 'colB'} | ORDER BY colB DESC
2672 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2674 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2676 \'colA DESC' | ORDER BY colA DESC
2678 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2679 | /* ...with $x bound to ? */
2682 { -asc => 'colA' }, | colA ASC,
2683 { -desc => [qw/colB/] }, | colB DESC,
2684 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2685 \'colE DESC', | colE DESC,
2686 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2687 ] | /* ...with $x bound to ? */
2688 ===============================================================
2692 =head1 SPECIAL OPERATORS
2694 my $sqlmaker = SQL::Abstract->new(special_ops => [
2698 my ($self, $field, $op, $arg) = @_;
2704 handler => 'method_name',
2708 A "special operator" is a SQL syntactic clause that can be
2709 applied to a field, instead of a usual binary operator.
2712 WHERE field IN (?, ?, ?)
2713 WHERE field BETWEEN ? AND ?
2714 WHERE MATCH(field) AGAINST (?, ?)
2716 Special operators IN and BETWEEN are fairly standard and therefore
2717 are builtin within C<SQL::Abstract> (as the overridable methods
2718 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2719 like the MATCH .. AGAINST example above which is specific to MySQL,
2720 you can write your own operator handlers - supply a C<special_ops>
2721 argument to the C<new> method. That argument takes an arrayref of
2722 operator definitions; each operator definition is a hashref with two
2729 the regular expression to match the operator
2733 Either a coderef or a plain scalar method name. In both cases
2734 the expected return is C<< ($sql, @bind) >>.
2736 When supplied with a method name, it is simply called on the
2737 L<SQL::Abstract> object as:
2739 $self->$method_name($field, $op, $arg)
2743 $field is the LHS of the operator
2744 $op is the part that matched the handler regex
2747 When supplied with a coderef, it is called as:
2749 $coderef->($self, $field, $op, $arg)
2754 For example, here is an implementation
2755 of the MATCH .. AGAINST syntax for MySQL
2757 my $sqlmaker = SQL::Abstract->new(special_ops => [
2759 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2760 {regex => qr/^match$/i,
2762 my ($self, $field, $op, $arg) = @_;
2763 $arg = [$arg] if not ref $arg;
2764 my $label = $self->_quote($field);
2765 my ($placeholder) = $self->_convert('?');
2766 my $placeholders = join ", ", (($placeholder) x @$arg);
2767 my $sql = $self->_sqlcase('match') . " ($label) "
2768 . $self->_sqlcase('against') . " ($placeholders) ";
2769 my @bind = $self->_bindtype($field, @$arg);
2770 return ($sql, @bind);
2777 =head1 UNARY OPERATORS
2779 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2783 my ($self, $op, $arg) = @_;
2789 handler => 'method_name',
2793 A "unary operator" is a SQL syntactic clause that can be
2794 applied to a field - the operator goes before the field
2796 You can write your own operator handlers - supply a C<unary_ops>
2797 argument to the C<new> method. That argument takes an arrayref of
2798 operator definitions; each operator definition is a hashref with two
2805 the regular expression to match the operator
2809 Either a coderef or a plain scalar method name. In both cases
2810 the expected return is C<< $sql >>.
2812 When supplied with a method name, it is simply called on the
2813 L<SQL::Abstract> object as:
2815 $self->$method_name($op, $arg)
2819 $op is the part that matched the handler regex
2820 $arg is the RHS or argument of the operator
2822 When supplied with a coderef, it is called as:
2824 $coderef->($self, $op, $arg)
2832 Thanks to some benchmarking by Mark Stosberg, it turns out that
2833 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2834 I must admit this wasn't an intentional design issue, but it's a
2835 byproduct of the fact that you get to control your C<DBI> handles
2838 To maximize performance, use a code snippet like the following:
2840 # prepare a statement handle using the first row
2841 # and then reuse it for the rest of the rows
2843 for my $href (@array_of_hashrefs) {
2844 $stmt ||= $sql->insert('table', $href);
2845 $sth ||= $dbh->prepare($stmt);
2846 $sth->execute($sql->values($href));
2849 The reason this works is because the keys in your C<$href> are sorted
2850 internally by B<SQL::Abstract>. Thus, as long as your data retains
2851 the same structure, you only have to generate the SQL the first time
2852 around. On subsequent queries, simply use the C<values> function provided
2853 by this module to return your values in the correct order.
2855 However this depends on the values having the same type - if, for
2856 example, the values of a where clause may either have values
2857 (resulting in sql of the form C<column = ?> with a single bind
2858 value), or alternatively the values might be C<undef> (resulting in
2859 sql of the form C<column IS NULL> with no bind value) then the
2860 caching technique suggested will not work.
2864 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2865 really like this part (I do, at least). Building up a complex query
2866 can be as simple as the following:
2873 use CGI::FormBuilder;
2876 my $form = CGI::FormBuilder->new(...);
2877 my $sql = SQL::Abstract->new;
2879 if ($form->submitted) {
2880 my $field = $form->field;
2881 my $id = delete $field->{id};
2882 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2885 Of course, you would still have to connect using C<DBI> to run the
2886 query, but the point is that if you make your form look like your
2887 table, the actual query script can be extremely simplistic.
2889 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2890 a fast interface to returning and formatting data. I frequently
2891 use these three modules together to write complex database query
2892 apps in under 50 lines.
2894 =head1 HOW TO CONTRIBUTE
2896 Contributions are always welcome, in all usable forms (we especially
2897 welcome documentation improvements). The delivery methods include git-
2898 or unified-diff formatted patches, GitHub pull requests, or plain bug
2899 reports either via RT or the Mailing list. Contributors are generally
2900 granted full access to the official repository after their first several
2901 patches pass successful review.
2903 This project is maintained in a git repository. The code and related tools are
2904 accessible at the following locations:
2908 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2910 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2912 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2914 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2920 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2921 Great care has been taken to preserve the I<published> behavior
2922 documented in previous versions in the 1.* family; however,
2923 some features that were previously undocumented, or behaved
2924 differently from the documentation, had to be changed in order
2925 to clarify the semantics. Hence, client code that was relying
2926 on some dark areas of C<SQL::Abstract> v1.*
2927 B<might behave differently> in v1.50.
2929 The main changes are:
2935 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2939 support for the { operator => \"..." } construct (to embed literal SQL)
2943 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2947 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2951 defensive programming: check arguments
2955 fixed bug with global logic, which was previously implemented
2956 through global variables yielding side-effects. Prior versions would
2957 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2958 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2959 Now this is interpreted
2960 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2965 fixed semantics of _bindtype on array args
2969 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2970 we just avoid shifting arrays within that tree.
2974 dropped the C<_modlogic> function
2978 =head1 ACKNOWLEDGEMENTS
2980 There are a number of individuals that have really helped out with
2981 this module. Unfortunately, most of them submitted bugs via CPAN
2982 so I have no idea who they are! But the people I do know are:
2984 Ash Berlin (order_by hash term support)
2985 Matt Trout (DBIx::Class support)
2986 Mark Stosberg (benchmarking)
2987 Chas Owens (initial "IN" operator support)
2988 Philip Collins (per-field SQL functions)
2989 Eric Kolve (hashref "AND" support)
2990 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2991 Dan Kubb (support for "quote_char" and "name_sep")
2992 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2993 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2994 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2995 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2996 Oliver Charles (support for "RETURNING" after "INSERT")
3002 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3006 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3008 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3010 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3011 While not an official support venue, C<DBIx::Class> makes heavy use of
3012 C<SQL::Abstract>, and as such list members there are very familiar with
3013 how to create queries.
3017 This module is free software; you may copy this under the same
3018 terms as perl itself (either the GNU General Public License or
3019 the Artistic License)