1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.86';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => sub { die "NOPE" }},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => sub { die "NOPE" }},
42 {regex => qr/^ is (?: \s+ not )? $/ix, handler => sub { die "NOPE" }},
45 #======================================================================
46 # DEBUGGING AND ERROR REPORTING
47 #======================================================================
50 return unless $_[0]->{debug}; shift; # a little faster
51 my $func = (caller(1))[3];
52 warn "[$func] ", @_, "\n";
56 my($func) = (caller(1))[3];
57 Carp::carp "[$func] Warning: ", @_;
61 my($func) = (caller(1))[3];
62 Carp::croak "[$func] Fatal: ", @_;
65 sub is_literal_value ($) {
66 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
67 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
71 # FIXME XSify - this can be done so much more efficiently
72 sub is_plain_value ($) {
74 ! length ref $_[0] ? \($_[0])
76 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
78 exists $_[0]->{-value}
79 ) ? \($_[0]->{-value})
81 # reuse @_ for even moar speedz
82 defined ( $_[1] = Scalar::Util::blessed $_[0] )
84 # deliberately not using Devel::OverloadInfo - the checks we are
85 # intersted in are much more limited than the fullblown thing, and
86 # this is a very hot piece of code
88 # simply using ->can('(""') can leave behind stub methods that
89 # break actually using the overload later (see L<perldiag/Stub
90 # found while resolving method "%s" overloading "%s" in package
91 # "%s"> and the source of overload::mycan())
93 # either has stringification which DBI SHOULD prefer out of the box
94 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
96 # has nummification or boolification, AND fallback is *not* disabled
98 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
101 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
103 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
107 # no fallback specified at all
108 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
110 # fallback explicitly undef
111 ! defined ${"$_[3]::()"}
124 #======================================================================
126 #======================================================================
130 my $class = ref($self) || $self;
131 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
133 # choose our case by keeping an option around
134 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
136 # default logic for interpreting arrayrefs
137 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
139 # how to return bind vars
140 $opt{bindtype} ||= 'normal';
142 # default comparison is "=", but can be overridden
145 # try to recognize which are the 'equality' and 'inequality' ops
146 # (temporary quickfix (in 2007), should go through a more seasoned API)
147 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
148 $opt{inequality_op} = qr/^( != | <> )$/ix;
150 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
151 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
154 $opt{sqltrue} ||= '1=1';
155 $opt{sqlfalse} ||= '0=1';
158 $opt{special_ops} ||= [];
160 # regexes are applied in order, thus push after user-defines
161 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
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 $set = { -bind => $_ } unless defined $set;
386 +{ -op => [ '=', { -ident => $k }, $set ] };
392 ? ($self->{array_datatypes}
393 ? [ $k, +{ -bind => [ $k, $v ] } ]
394 : [ $k, +{ -literal => $v } ])
396 local our $Cur_Col_Meta = $k;
397 [ $k, $self->_expand_expr($v) ]
404 # So that subclasses can override UPDATE ... RETURNING separately from
406 sub _update_returning { shift->_returning(@_) }
410 #======================================================================
412 #======================================================================
417 my $table = $self->_table(shift);
418 my $fields = shift || '*';
422 my ($fields_sql, @bind) = $self->_select_fields($fields);
424 my ($where_sql, @where_bind) = $self->where($where, $order);
425 push @bind, @where_bind;
427 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
428 $self->_sqlcase('from'), $table)
431 return wantarray ? ($sql, @bind) : $sql;
435 my ($self, $fields) = @_;
436 return $fields unless ref($fields);
437 return $self->_render_expr(
438 $self->_expand_maybe_list_expr($fields, undef, '-ident')
442 #======================================================================
444 #======================================================================
449 my $table = $self->_table(shift);
453 my($where_sql, @bind) = $self->where($where);
454 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
456 if ($options->{returning}) {
457 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
458 $sql .= $returning_sql;
459 push @bind, @returning_bind;
462 return wantarray ? ($sql, @bind) : $sql;
465 # So that subclasses can override DELETE ... RETURNING separately from
467 sub _delete_returning { shift->_returning(@_) }
471 #======================================================================
473 #======================================================================
477 # Finally, a separate routine just to handle WHERE clauses
479 my ($self, $where, $order) = @_;
481 local $self->{convert_where} = $self->{convert};
484 my ($sql, @bind) = defined($where)
485 ? $self->_recurse_where($where)
487 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
491 my ($order_sql, @order_bind) = $self->_order_by($order);
493 push @bind, @order_bind;
496 return wantarray ? ($sql, @bind) : $sql;
500 my ($self, $expr, $logic, $default_scalar_to) = @_;
501 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
502 return undef unless defined($expr);
503 if (ref($expr) eq 'HASH') {
504 if (keys %$expr > 1) {
508 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
512 return unless %$expr;
513 return $self->_expand_expr_hashpair(%$expr, $logic);
515 if (ref($expr) eq 'ARRAY') {
516 my $logic = lc($logic || $self->{logic});
517 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
523 while (my ($el) = splice @expr, 0, 1) {
524 puke "Supplying an empty left hand side argument is not supported in array-pairs"
525 unless defined($el) and length($el);
526 my $elref = ref($el);
528 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
529 } elsif ($elref eq 'ARRAY') {
530 push(@res, $self->_expand_expr($el)) if @$el;
531 } elsif (my $l = is_literal_value($el)) {
532 push @res, { -literal => $l };
533 } elsif ($elref eq 'HASH') {
534 push @res, $self->_expand_expr($el);
539 return { -op => [ $logic, @res ] };
541 if (my $literal = is_literal_value($expr)) {
542 return +{ -literal => $literal };
544 if (!ref($expr) or Scalar::Util::blessed($expr)) {
545 if (my $d = $Default_Scalar_To) {
546 return +{ $d => $expr };
548 if (my $m = our $Cur_Col_Meta) {
549 return +{ -bind => [ $m, $expr ] };
551 return +{ -value => $expr };
556 our $Nest_Warning_Emitted = 0;
558 sub _expand_expr_hashpair {
559 my ($self, $k, $v, $logic) = @_;
560 unless (defined($k) and length($k)) {
561 if (defined($k) and my $literal = is_literal_value($v)) {
562 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
563 return { -literal => $literal };
565 puke "Supplying an empty left hand side argument is not supported";
568 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
569 if ($k =~ s/ [_\s]? \d+ $//x ) {
570 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
571 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
575 "-nest in search conditions is deprecated, you most probably wanted:\n"
576 .q|{..., -and => [ \%cond0, \@cond1, \'cond2', \[ 'cond3', [ col => bind ] ], etc. ], ... }|
577 ) unless $Nest_Warning_Emitted++;
578 return $self->_expand_expr($v);
582 return $self->_expand_expr($v);
584 puke "-bool => undef not supported" unless defined($v);
585 return { -ident => $v };
588 return { -op => [ 'not', $self->_expand_expr($v) ] };
590 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
593 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
596 if (my ($logic) = $k =~ /^-(and|or)$/i) {
597 if (ref($v) eq 'HASH') {
598 return $self->_expand_expr($v, $logic);
600 if (ref($v) eq 'ARRAY') {
601 return $self->_expand_expr($v, $logic);
606 $op =~ s/^-// if length($op) > 1;
608 # top level special ops are illegal in general
609 puke "Illegal use of top-level '-$op'"
610 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
611 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
612 return { -op => [ $op, $v ] };
615 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
616 return +{ -bind => [ $m, $v ] };
618 if (my $custom = $self->{expand_unary}{$k}) {
619 return $self->$custom($v);
621 if ($self->{node_types}{$k}) {
627 and (keys %$v)[0] =~ /^-/
629 my ($func) = $k =~ /^-(.*)$/;
630 return +{ -func => [ $func, $self->_expand_expr($v) ] };
632 if (!ref($v) or is_literal_value($v)) {
633 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
640 and exists $v->{-value}
641 and not defined $v->{-value}
644 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
646 if (!ref($v) or Scalar::Util::blessed($v)) {
647 my $d = our $Default_Scalar_To;
652 ($d ? { $d => $v } : { -bind => [ $k, $v ] })
656 if (ref($v) eq 'HASH') {
660 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
667 $self->_assert_pass_injection_guard($vk);
668 if ($vk =~ s/ [_\s]? \d+ $//x ) {
669 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
670 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
672 if ($vk =~ /^(?:not[ _])?between$/) {
673 local our $Cur_Col_Meta = $k;
674 my @rhs = map $self->_expand_expr($_),
675 ref($vv) eq 'ARRAY' ? @$vv : $vv;
677 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
679 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
681 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
684 join(' ', split '_', $vk),
689 if ($vk =~ /^(?:not[ _])?in$/) {
690 if (my $literal = is_literal_value($vv)) {
691 my ($sql, @bind) = @$literal;
692 my $opened_sql = $self->_open_outer_paren($sql);
694 $vk, { -ident => $k },
695 [ { -literal => [ $opened_sql, @bind ] } ]
699 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
700 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
701 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
702 . 'will emit the logically correct SQL instead of raising this exception)'
704 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
706 my @rhs = map $self->_expand_expr($_),
707 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
708 map { defined($_) ? $_: puke($undef_err) }
709 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
710 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
713 join(' ', split '_', $vk),
718 if ($vk eq 'ident') {
719 if (! defined $vv or (ref($vv) and ref($vv) eq 'ARRAY')) {
720 puke "-$vk requires a single plain scalar argument (a quotable identifier) or an arrayref of identifier parts";
728 if ($vk eq 'value') {
729 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
733 { -bind => [ $k, $vv ] }
736 if ($vk =~ /^is(?:[ _]not)?$/) {
737 puke "$vk can only take undef as argument"
741 and exists($vv->{-value})
742 and !defined($vv->{-value})
745 return +{ -op => [ $vk.' null', { -ident => $k } ] };
747 if ($vk =~ /^(and|or)$/) {
748 if (ref($vv) eq 'HASH') {
751 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
756 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{special_ops}}) {
757 return { -op => [ $vk, { -ident => $k }, $vv ] };
759 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{unary_ops}}) {
763 { -op => [ $vk, $vv ] }
766 if (ref($vv) eq 'ARRAY') {
767 my ($logic, @values) = (
768 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
773 $vk =~ $self->{inequality_op}
774 or join(' ', split '_', $vk) =~ $self->{not_like_op}
776 if (lc($logic) eq '-or' and @values > 1) {
777 my $op = uc join ' ', split '_', $vk;
778 belch "A multi-element arrayref as an argument to the inequality op '$op' "
779 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
780 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
785 # try to DWIM on equality operators
786 my $op = join ' ', split '_', $vk;
788 $op =~ $self->{equality_op} ? $self->sqlfalse
789 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
790 : $op =~ $self->{inequality_op} ? $self->sqltrue
791 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
792 : puke "operator '$op' applied on an empty array (field '$k')";
796 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
804 and exists $vv->{-value}
805 and not defined $vv->{-value}
808 my $op = join ' ', split '_', $vk;
810 $op =~ /^not$/i ? 'is not' # legacy
811 : $op =~ $self->{equality_op} ? 'is'
812 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
813 : $op =~ $self->{inequality_op} ? 'is not'
814 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
815 : puke "unexpected operator '$op' with undef operand";
816 return +{ -op => [ $is.' null', { -ident => $k } ] };
818 local our $Cur_Col_Meta = $k;
822 $self->_expand_expr($vv)
825 if (ref($v) eq 'ARRAY') {
826 return $self->sqlfalse unless @$v;
827 $self->_debug("ARRAY($k) means distribute over elements");
829 $v->[0] =~ /^-((?:and|or))$/i
830 ? ($v = [ @{$v}[1..$#$v] ], $1)
831 : ($self->{logic} || 'or')
835 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
838 if (my $literal = is_literal_value($v)) {
840 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
843 my ($sql, @bind) = @$literal;
844 if ($self->{bindtype} eq 'columns') {
846 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
847 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
851 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
857 my ($self, $expr) = @_;
858 my ($k, $v, @rest) = %$expr;
860 if (my $meth = $self->{node_types}{$k}) {
861 return $self->$meth($v);
863 die "notreached: $k";
867 my ($self, $where, $logic) = @_;
869 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
871 # Special case: top level simple string treated as literal
873 my $where_exp = (ref($where)
874 ? $self->_expand_expr($where, $logic)
875 : { -literal => [ $where ] });
877 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
879 # dispatch on appropriate method according to refkind of $where
880 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
882 # my ($sql, @bind) = $self->$method($where_exp, $logic);
884 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
886 # DBIx::Class used to call _recurse_where in scalar context
887 # something else might too...
889 return ($sql, @bind);
892 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
898 my ($self, $ident) = @_;
900 return $self->_convert($self->_quote($ident));
904 my ($self, $value) = @_;
906 return ($self->_convert('?'), $self->_bindtype(undef, $value));
909 my %unop_postfix = map +($_ => 1),
910 'is null', 'is not null',
918 my ($self, $args) = @_;
919 my ($left, $low, $high) = @$args;
920 my ($rhsql, @rhbind) = do {
922 puke "Single arg to between must be a literal"
923 unless $low->{-literal};
926 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
927 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
928 @{$l}[1..$#$l], @{$h}[1..$#$h])
931 my ($lhsql, @lhbind) = $self->_render_expr($left);
933 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
937 }), 'between', 'not between'),
941 my ($self, $args) = @_;
942 my ($lhs, $rhs) = @$args;
945 my ($sql, @bind) = $self->_render_expr($_);
946 push @in_bind, @bind;
949 my ($lhsql, @lbind) = $self->_render_expr($lhs);
951 $lhsql.' '.$self->_sqlcase($op).' ( '
962 my ($op, @args) = @$v;
963 $op =~ s/^-// if length($op) > 1;
965 if (my $h = $special{$op}) {
966 return $self->$h(\@args);
968 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}}) {
969 puke "Special op '${op}' requires first value to be identifier"
970 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
971 return $self->${\($us->{handler})}($k, $op, $args[1]);
973 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{unary_ops}}) {
974 return $self->${\($us->{handler})}($op, $args[0]);
976 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
977 if (@args == 1 and $op !~ /^(and|or)$/) {
978 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
979 my $op_sql = $self->_sqlcase($final_op);
981 $unop_postfix{lc($final_op)}
982 ? "${expr_sql} ${op_sql}"
983 : "${op_sql} ${expr_sql}"
985 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
987 my @parts = map [ $self->_render_expr($_) ], @args;
988 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
989 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
994 map @{$_}[1..$#$_], @parts
1001 my ($self, $rest) = @_;
1002 my ($func, @args) = @$rest;
1006 push @arg_sql, shift @x;
1008 } map [ $self->_render_expr($_) ], @args;
1009 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1013 my ($self, $bind) = @_;
1014 return ($self->_convert('?'), $self->_bindtype(@$bind));
1017 sub _render_literal {
1018 my ($self, $literal) = @_;
1019 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1023 # Some databases (SQLite) treat col IN (1, 2) different from
1024 # col IN ( (1, 2) ). Use this to strip all outer parens while
1025 # adding them back in the corresponding method
1026 sub _open_outer_paren {
1027 my ($self, $sql) = @_;
1029 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1031 # there are closing parens inside, need the heavy duty machinery
1032 # to reevaluate the extraction starting from $sql (full reevaluation)
1033 if ($inner =~ /\)/) {
1034 require Text::Balanced;
1036 my (undef, $remainder) = do {
1037 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1039 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1042 # the entire expression needs to be a balanced bracketed thing
1043 # (after an extract no remainder sans trailing space)
1044 last if defined $remainder and $remainder =~ /\S/;
1054 #======================================================================
1056 #======================================================================
1058 sub _expand_order_by {
1059 my ($self, $arg) = @_;
1061 return unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1063 my $expander = sub {
1064 my ($self, $dir, $expr) = @_;
1065 my @to_expand = ref($expr) eq 'ARRAY' ? @$expr : $expr;
1066 foreach my $arg (@to_expand) {
1070 and grep /^-(asc|desc)$/, keys %$arg
1072 puke "ordering direction hash passed to order by must have exactly one key (-asc or -desc)";
1075 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1076 map $self->_expand_expr($_, undef, -ident),
1077 map ref($_) eq 'ARRAY' ? @$_ : $_, @to_expand;
1078 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1081 local @{$self->{expand_unary}}{qw(-asc -desc)} = (
1082 sub { shift->$expander(asc => @_) },
1083 sub { shift->$expander(desc => @_) },
1086 return $self->$expander(undef, $arg);
1090 my ($self, $arg) = @_;
1092 return '' unless defined(my $expanded = $self->_expand_order_by($arg));
1094 my ($sql, @bind) = $self->_render_expr($expanded);
1096 my $final_sql = $self->_sqlcase(' order by ').$sql;
1098 return wantarray ? ($final_sql, @bind) : $final_sql;
1101 sub _order_by_chunks {
1102 my ($self, $arg) = @_;
1104 return () unless defined(my $expanded = $self->_expand_order_by($arg));
1107 if (ref() eq 'HASH' and my $op = $_->{-op}) {
1108 if ($op->[0] eq ',') {
1109 return map [ $self->_render_expr($_) ], @{$op}[1..$#$op];
1112 return [ $self->_render_expr($_) ];
1116 #======================================================================
1117 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1118 #======================================================================
1123 ($self->_render_expr(
1124 $self->_expand_maybe_list_expr($from, undef, -ident)
1129 #======================================================================
1131 #======================================================================
1133 sub _expand_maybe_list_expr {
1134 my ($self, $expr, $logic, $default) = @_;
1136 if (ref($expr) eq 'ARRAY') {
1138 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1145 return $self->_expand_expr($e, $logic, $default);
1148 # highly optimized, as it's called way too often
1150 # my ($self, $label) = @_;
1152 return '' unless defined $_[1];
1153 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1154 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1156 unless ($_[0]->{quote_char}) {
1157 if (ref($_[1]) eq 'ARRAY') {
1158 return join($_[0]->{name_sep}||'.', @{$_[1]});
1160 $_[0]->_assert_pass_injection_guard($_[1]);
1165 my $qref = ref $_[0]->{quote_char};
1167 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1168 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1169 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1171 my $esc = $_[0]->{escape_char} || $r;
1173 # parts containing * are naturally unquoted
1175 $_[0]->{name_sep}||'',
1179 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1181 (ref($_[1]) eq 'ARRAY'
1185 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1193 # Conversion, if applicable
1195 #my ($self, $arg) = @_;
1196 if ($_[0]->{convert_where}) {
1197 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1204 #my ($self, $col, @vals) = @_;
1205 # called often - tighten code
1206 return $_[0]->{bindtype} eq 'columns'
1207 ? map {[$_[1], $_]} @_[2 .. $#_]
1212 # Dies if any element of @bind is not in [colname => value] format
1213 # if bindtype is 'columns'.
1214 sub _assert_bindval_matches_bindtype {
1215 # my ($self, @bind) = @_;
1217 if ($self->{bindtype} eq 'columns') {
1219 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1220 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1226 sub _join_sql_clauses {
1227 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1229 if (@$clauses_aref > 1) {
1230 my $join = " " . $self->_sqlcase($logic) . " ";
1231 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1232 return ($sql, @$bind_aref);
1234 elsif (@$clauses_aref) {
1235 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1238 return (); # if no SQL, ignore @$bind_aref
1243 # Fix SQL case, if so requested
1245 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1246 # don't touch the argument ... crooked logic, but let's not change it!
1247 return $_[0]->{case} ? $_[1] : uc($_[1]);
1251 #======================================================================
1252 # DISPATCHING FROM REFKIND
1253 #======================================================================
1256 my ($self, $data) = @_;
1258 return 'UNDEF' unless defined $data;
1260 # blessed objects are treated like scalars
1261 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1263 return 'SCALAR' unless $ref;
1266 while ($ref eq 'REF') {
1268 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1272 return ($ref||'SCALAR') . ('REF' x $n_steps);
1276 my ($self, $data) = @_;
1277 my @try = ($self->_refkind($data));
1278 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1279 push @try, 'FALLBACK';
1283 sub _METHOD_FOR_refkind {
1284 my ($self, $meth_prefix, $data) = @_;
1287 for (@{$self->_try_refkind($data)}) {
1288 $method = $self->can($meth_prefix."_".$_)
1292 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1296 sub _SWITCH_refkind {
1297 my ($self, $data, $dispatch_table) = @_;
1300 for (@{$self->_try_refkind($data)}) {
1301 $coderef = $dispatch_table->{$_}
1305 puke "no dispatch entry for ".$self->_refkind($data)
1314 #======================================================================
1315 # VALUES, GENERATE, AUTOLOAD
1316 #======================================================================
1318 # LDNOTE: original code from nwiger, didn't touch code in that section
1319 # I feel the AUTOLOAD stuff should not be the default, it should
1320 # only be activated on explicit demand by user.
1324 my $data = shift || return;
1325 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1326 unless ref $data eq 'HASH';
1329 foreach my $k (sort keys %$data) {
1330 my $v = $data->{$k};
1331 $self->_SWITCH_refkind($v, {
1333 if ($self->{array_datatypes}) { # array datatype
1334 push @all_bind, $self->_bindtype($k, $v);
1336 else { # literal SQL with bind
1337 my ($sql, @bind) = @$v;
1338 $self->_assert_bindval_matches_bindtype(@bind);
1339 push @all_bind, @bind;
1342 ARRAYREFREF => sub { # literal SQL with bind
1343 my ($sql, @bind) = @${$v};
1344 $self->_assert_bindval_matches_bindtype(@bind);
1345 push @all_bind, @bind;
1347 SCALARREF => sub { # literal SQL without bind
1349 SCALAR_or_UNDEF => sub {
1350 push @all_bind, $self->_bindtype($k, $v);
1361 my(@sql, @sqlq, @sqlv);
1365 if ($ref eq 'HASH') {
1366 for my $k (sort keys %$_) {
1369 my $label = $self->_quote($k);
1370 if ($r eq 'ARRAY') {
1371 # literal SQL with bind
1372 my ($sql, @bind) = @$v;
1373 $self->_assert_bindval_matches_bindtype(@bind);
1374 push @sqlq, "$label = $sql";
1376 } elsif ($r eq 'SCALAR') {
1377 # literal SQL without bind
1378 push @sqlq, "$label = $$v";
1380 push @sqlq, "$label = ?";
1381 push @sqlv, $self->_bindtype($k, $v);
1384 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1385 } elsif ($ref eq 'ARRAY') {
1386 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1389 if ($r eq 'ARRAY') { # literal SQL with bind
1390 my ($sql, @bind) = @$v;
1391 $self->_assert_bindval_matches_bindtype(@bind);
1394 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1395 # embedded literal SQL
1402 push @sql, '(' . join(', ', @sqlq) . ')';
1403 } elsif ($ref eq 'SCALAR') {
1407 # strings get case twiddled
1408 push @sql, $self->_sqlcase($_);
1412 my $sql = join ' ', @sql;
1414 # this is pretty tricky
1415 # if ask for an array, return ($stmt, @bind)
1416 # otherwise, s/?/shift @sqlv/ to put it inline
1418 return ($sql, @sqlv);
1420 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1421 ref $d ? $d->[1] : $d/e;
1430 # This allows us to check for a local, then _form, attr
1432 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1433 return $self->generate($name, @_);
1444 SQL::Abstract - Generate SQL from Perl data structures
1450 my $sql = SQL::Abstract->new;
1452 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1454 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1456 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1458 my($stmt, @bind) = $sql->delete($table, \%where);
1460 # Then, use these in your DBI statements
1461 my $sth = $dbh->prepare($stmt);
1462 $sth->execute(@bind);
1464 # Just generate the WHERE clause
1465 my($stmt, @bind) = $sql->where(\%where, $order);
1467 # Return values in the same order, for hashed queries
1468 # See PERFORMANCE section for more details
1469 my @bind = $sql->values(\%fieldvals);
1473 This module was inspired by the excellent L<DBIx::Abstract>.
1474 However, in using that module I found that what I really wanted
1475 to do was generate SQL, but still retain complete control over my
1476 statement handles and use the DBI interface. So, I set out to
1477 create an abstract SQL generation module.
1479 While based on the concepts used by L<DBIx::Abstract>, there are
1480 several important differences, especially when it comes to WHERE
1481 clauses. I have modified the concepts used to make the SQL easier
1482 to generate from Perl data structures and, IMO, more intuitive.
1483 The underlying idea is for this module to do what you mean, based
1484 on the data structures you provide it. The big advantage is that
1485 you don't have to modify your code every time your data changes,
1486 as this module figures it out.
1488 To begin with, an SQL INSERT is as easy as just specifying a hash
1489 of C<key=value> pairs:
1492 name => 'Jimbo Bobson',
1493 phone => '123-456-7890',
1494 address => '42 Sister Lane',
1495 city => 'St. Louis',
1496 state => 'Louisiana',
1499 The SQL can then be generated with this:
1501 my($stmt, @bind) = $sql->insert('people', \%data);
1503 Which would give you something like this:
1505 $stmt = "INSERT INTO people
1506 (address, city, name, phone, state)
1507 VALUES (?, ?, ?, ?, ?)";
1508 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1509 '123-456-7890', 'Louisiana');
1511 These are then used directly in your DBI code:
1513 my $sth = $dbh->prepare($stmt);
1514 $sth->execute(@bind);
1516 =head2 Inserting and Updating Arrays
1518 If your database has array types (like for example Postgres),
1519 activate the special option C<< array_datatypes => 1 >>
1520 when creating the C<SQL::Abstract> object.
1521 Then you may use an arrayref to insert and update database array types:
1523 my $sql = SQL::Abstract->new(array_datatypes => 1);
1525 planets => [qw/Mercury Venus Earth Mars/]
1528 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1532 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1534 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1537 =head2 Inserting and Updating SQL
1539 In order to apply SQL functions to elements of your C<%data> you may
1540 specify a reference to an arrayref for the given hash value. For example,
1541 if you need to execute the Oracle C<to_date> function on a value, you can
1542 say something like this:
1546 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1549 The first value in the array is the actual SQL. Any other values are
1550 optional and would be included in the bind values array. This gives
1553 my($stmt, @bind) = $sql->insert('people', \%data);
1555 $stmt = "INSERT INTO people (name, date_entered)
1556 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1557 @bind = ('Bill', '03/02/2003');
1559 An UPDATE is just as easy, all you change is the name of the function:
1561 my($stmt, @bind) = $sql->update('people', \%data);
1563 Notice that your C<%data> isn't touched; the module will generate
1564 the appropriately quirky SQL for you automatically. Usually you'll
1565 want to specify a WHERE clause for your UPDATE, though, which is
1566 where handling C<%where> hashes comes in handy...
1568 =head2 Complex where statements
1570 This module can generate pretty complicated WHERE statements
1571 easily. For example, simple C<key=value> pairs are taken to mean
1572 equality, and if you want to see if a field is within a set
1573 of values, you can use an arrayref. Let's say we wanted to
1574 SELECT some data based on this criteria:
1577 requestor => 'inna',
1578 worker => ['nwiger', 'rcwe', 'sfz'],
1579 status => { '!=', 'completed' }
1582 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1584 The above would give you something like this:
1586 $stmt = "SELECT * FROM tickets WHERE
1587 ( requestor = ? ) AND ( status != ? )
1588 AND ( worker = ? OR worker = ? OR worker = ? )";
1589 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1591 Which you could then use in DBI code like so:
1593 my $sth = $dbh->prepare($stmt);
1594 $sth->execute(@bind);
1600 The methods are simple. There's one for every major SQL operation,
1601 and a constructor you use first. The arguments are specified in a
1602 similar order for each method (table, then fields, then a where
1603 clause) to try and simplify things.
1605 =head2 new(option => 'value')
1607 The C<new()> function takes a list of options and values, and returns
1608 a new B<SQL::Abstract> object which can then be used to generate SQL
1609 through the methods below. The options accepted are:
1615 If set to 'lower', then SQL will be generated in all lowercase. By
1616 default SQL is generated in "textbook" case meaning something like:
1618 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1620 Any setting other than 'lower' is ignored.
1624 This determines what the default comparison operator is. By default
1625 it is C<=>, meaning that a hash like this:
1627 %where = (name => 'nwiger', email => 'nate@wiger.org');
1629 Will generate SQL like this:
1631 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1633 However, you may want loose comparisons by default, so if you set
1634 C<cmp> to C<like> you would get SQL such as:
1636 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1638 You can also override the comparison on an individual basis - see
1639 the huge section on L</"WHERE CLAUSES"> at the bottom.
1641 =item sqltrue, sqlfalse
1643 Expressions for inserting boolean values within SQL statements.
1644 By default these are C<1=1> and C<1=0>. They are used
1645 by the special operators C<-in> and C<-not_in> for generating
1646 correct SQL even when the argument is an empty array (see below).
1650 This determines the default logical operator for multiple WHERE
1651 statements in arrays or hashes. If absent, the default logic is "or"
1652 for arrays, and "and" for hashes. This means that a WHERE
1656 event_date => {'>=', '2/13/99'},
1657 event_date => {'<=', '4/24/03'},
1660 will generate SQL like this:
1662 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1664 This is probably not what you want given this query, though (look
1665 at the dates). To change the "OR" to an "AND", simply specify:
1667 my $sql = SQL::Abstract->new(logic => 'and');
1669 Which will change the above C<WHERE> to:
1671 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1673 The logic can also be changed locally by inserting
1674 a modifier in front of an arrayref:
1676 @where = (-and => [event_date => {'>=', '2/13/99'},
1677 event_date => {'<=', '4/24/03'} ]);
1679 See the L</"WHERE CLAUSES"> section for explanations.
1683 This will automatically convert comparisons using the specified SQL
1684 function for both column and value. This is mostly used with an argument
1685 of C<upper> or C<lower>, so that the SQL will have the effect of
1686 case-insensitive "searches". For example, this:
1688 $sql = SQL::Abstract->new(convert => 'upper');
1689 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1691 Will turn out the following SQL:
1693 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1695 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1696 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1697 not validate this option; it will just pass through what you specify verbatim).
1701 This is a kludge because many databases suck. For example, you can't
1702 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1703 Instead, you have to use C<bind_param()>:
1705 $sth->bind_param(1, 'reg data');
1706 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1708 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1709 which loses track of which field each slot refers to. Fear not.
1711 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1712 Currently, you can specify either C<normal> (default) or C<columns>. If you
1713 specify C<columns>, you will get an array that looks like this:
1715 my $sql = SQL::Abstract->new(bindtype => 'columns');
1716 my($stmt, @bind) = $sql->insert(...);
1719 [ 'column1', 'value1' ],
1720 [ 'column2', 'value2' ],
1721 [ 'column3', 'value3' ],
1724 You can then iterate through this manually, using DBI's C<bind_param()>.
1726 $sth->prepare($stmt);
1729 my($col, $data) = @$_;
1730 if ($col eq 'details' || $col eq 'comments') {
1731 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1732 } elsif ($col eq 'image') {
1733 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1735 $sth->bind_param($i, $data);
1739 $sth->execute; # execute without @bind now
1741 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1742 Basically, the advantage is still that you don't have to care which fields
1743 are or are not included. You could wrap that above C<for> loop in a simple
1744 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1745 get a layer of abstraction over manual SQL specification.
1747 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1748 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1749 will expect the bind values in this format.
1753 This is the character that a table or column name will be quoted
1754 with. By default this is an empty string, but you could set it to
1755 the character C<`>, to generate SQL like this:
1757 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1759 Alternatively, you can supply an array ref of two items, the first being the left
1760 hand quote character, and the second the right hand quote character. For
1761 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1762 that generates SQL like this:
1764 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1766 Quoting is useful if you have tables or columns names that are reserved
1767 words in your database's SQL dialect.
1771 This is the character that will be used to escape L</quote_char>s appearing
1772 in an identifier before it has been quoted.
1774 The parameter default in case of a single L</quote_char> character is the quote
1777 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1778 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1779 of the B<opening (left)> L</quote_char> within the identifier are currently left
1780 untouched. The default for opening-closing-style quotes may change in future
1781 versions, thus you are B<strongly encouraged> to specify the escape character
1786 This is the character that separates a table and column name. It is
1787 necessary to specify this when the C<quote_char> option is selected,
1788 so that tables and column names can be individually quoted like this:
1790 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1792 =item injection_guard
1794 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1795 column name specified in a query structure. This is a safety mechanism to avoid
1796 injection attacks when mishandling user input e.g.:
1798 my %condition_as_column_value_pairs = get_values_from_user();
1799 $sqla->select( ... , \%condition_as_column_value_pairs );
1801 If the expression matches an exception is thrown. Note that literal SQL
1802 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1804 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1806 =item array_datatypes
1808 When this option is true, arrayrefs in INSERT or UPDATE are
1809 interpreted as array datatypes and are passed directly
1811 When this option is false, arrayrefs are interpreted
1812 as literal SQL, just like refs to arrayrefs
1813 (but this behavior is for backwards compatibility; when writing
1814 new queries, use the "reference to arrayref" syntax
1820 Takes a reference to a list of "special operators"
1821 to extend the syntax understood by L<SQL::Abstract>.
1822 See section L</"SPECIAL OPERATORS"> for details.
1826 Takes a reference to a list of "unary operators"
1827 to extend the syntax understood by L<SQL::Abstract>.
1828 See section L</"UNARY OPERATORS"> for details.
1834 =head2 insert($table, \@values || \%fieldvals, \%options)
1836 This is the simplest function. You simply give it a table name
1837 and either an arrayref of values or hashref of field/value pairs.
1838 It returns an SQL INSERT statement and a list of bind values.
1839 See the sections on L</"Inserting and Updating Arrays"> and
1840 L</"Inserting and Updating SQL"> for information on how to insert
1841 with those data types.
1843 The optional C<\%options> hash reference may contain additional
1844 options to generate the insert SQL. Currently supported options
1851 Takes either a scalar of raw SQL fields, or an array reference of
1852 field names, and adds on an SQL C<RETURNING> statement at the end.
1853 This allows you to return data generated by the insert statement
1854 (such as row IDs) without performing another C<SELECT> statement.
1855 Note, however, this is not part of the SQL standard and may not
1856 be supported by all database engines.
1860 =head2 update($table, \%fieldvals, \%where, \%options)
1862 This takes a table, hashref of field/value pairs, and an optional
1863 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1865 See the sections on L</"Inserting and Updating Arrays"> and
1866 L</"Inserting and Updating SQL"> for information on how to insert
1867 with those data types.
1869 The optional C<\%options> hash reference may contain additional
1870 options to generate the update SQL. Currently supported options
1877 See the C<returning> option to
1878 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1882 =head2 select($source, $fields, $where, $order)
1884 This returns a SQL SELECT statement and associated list of bind values, as
1885 specified by the arguments:
1891 Specification of the 'FROM' part of the statement.
1892 The argument can be either a plain scalar (interpreted as a table
1893 name, will be quoted), or an arrayref (interpreted as a list
1894 of table names, joined by commas, quoted), or a scalarref
1895 (literal SQL, not quoted).
1899 Specification of the list of fields to retrieve from
1901 The argument can be either an arrayref (interpreted as a list
1902 of field names, will be joined by commas and quoted), or a
1903 plain scalar (literal SQL, not quoted).
1904 Please observe that this API is not as flexible as that of
1905 the first argument C<$source>, for backwards compatibility reasons.
1909 Optional argument to specify the WHERE part of the query.
1910 The argument is most often a hashref, but can also be
1911 an arrayref or plain scalar --
1912 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1916 Optional argument to specify the ORDER BY part of the query.
1917 The argument can be a scalar, a hashref or an arrayref
1918 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1924 =head2 delete($table, \%where, \%options)
1926 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1927 It returns an SQL DELETE statement and list of bind values.
1929 The optional C<\%options> hash reference may contain additional
1930 options to generate the delete SQL. Currently supported options
1937 See the C<returning> option to
1938 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1942 =head2 where(\%where, $order)
1944 This is used to generate just the WHERE clause. For example,
1945 if you have an arbitrary data structure and know what the
1946 rest of your SQL is going to look like, but want an easy way
1947 to produce a WHERE clause, use this. It returns an SQL WHERE
1948 clause and list of bind values.
1951 =head2 values(\%data)
1953 This just returns the values from the hash C<%data>, in the same
1954 order that would be returned from any of the other above queries.
1955 Using this allows you to markedly speed up your queries if you
1956 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1958 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1960 Warning: This is an experimental method and subject to change.
1962 This returns arbitrarily generated SQL. It's a really basic shortcut.
1963 It will return two different things, depending on return context:
1965 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1966 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1968 These would return the following:
1970 # First calling form
1971 $stmt = "CREATE TABLE test (?, ?)";
1972 @bind = (field1, field2);
1974 # Second calling form
1975 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1977 Depending on what you're trying to do, it's up to you to choose the correct
1978 format. In this example, the second form is what you would want.
1982 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1986 ALTER SESSION SET nls_date_format = 'MM/YY'
1988 You get the idea. Strings get their case twiddled, but everything
1989 else remains verbatim.
1991 =head1 EXPORTABLE FUNCTIONS
1993 =head2 is_plain_value
1995 Determines if the supplied argument is a plain value as understood by this
2000 =item * The value is C<undef>
2002 =item * The value is a non-reference
2004 =item * The value is an object with stringification overloading
2006 =item * The value is of the form C<< { -value => $anything } >>
2010 On failure returns C<undef>, on success returns a B<scalar> reference
2011 to the original supplied argument.
2017 The stringification overloading detection is rather advanced: it takes
2018 into consideration not only the presence of a C<""> overload, but if that
2019 fails also checks for enabled
2020 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2021 on either C<0+> or C<bool>.
2023 Unfortunately testing in the field indicates that this
2024 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2025 but only when very large numbers of stringifying objects are involved.
2026 At the time of writing ( Sep 2014 ) there is no clear explanation of
2027 the direct cause, nor is there a manageably small test case that reliably
2028 reproduces the problem.
2030 If you encounter any of the following exceptions in B<random places within
2031 your application stack> - this module may be to blame:
2033 Operation "ne": no method found,
2034 left argument in overloaded package <something>,
2035 right argument in overloaded package <something>
2039 Stub found while resolving method "???" overloading """" in package <something>
2041 If you fall victim to the above - please attempt to reduce the problem
2042 to something that could be sent to the L<SQL::Abstract developers
2043 |DBIx::Class/GETTING HELP/SUPPORT>
2044 (either publicly or privately). As a workaround in the meantime you can
2045 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2046 value, which will most likely eliminate your problem (at the expense of
2047 not being able to properly detect exotic forms of stringification).
2049 This notice and environment variable will be removed in a future version,
2050 as soon as the underlying problem is found and a reliable workaround is
2055 =head2 is_literal_value
2057 Determines if the supplied argument is a literal value as understood by this
2062 =item * C<\$sql_string>
2064 =item * C<\[ $sql_string, @bind_values ]>
2068 On failure returns C<undef>, on success returns an B<array> reference
2069 containing the unpacked version of the supplied literal SQL and bind values.
2071 =head1 WHERE CLAUSES
2075 This module uses a variation on the idea from L<DBIx::Abstract>. It
2076 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2077 module is that things in arrays are OR'ed, and things in hashes
2080 The easiest way to explain is to show lots of examples. After
2081 each C<%where> hash shown, it is assumed you used:
2083 my($stmt, @bind) = $sql->where(\%where);
2085 However, note that the C<%where> hash can be used directly in any
2086 of the other functions as well, as described above.
2088 =head2 Key-value pairs
2090 So, let's get started. To begin, a simple hash:
2094 status => 'completed'
2097 Is converted to SQL C<key = val> statements:
2099 $stmt = "WHERE user = ? AND status = ?";
2100 @bind = ('nwiger', 'completed');
2102 One common thing I end up doing is having a list of values that
2103 a field can be in. To do this, simply specify a list inside of
2108 status => ['assigned', 'in-progress', 'pending'];
2111 This simple code will create the following:
2113 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2114 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2116 A field associated to an empty arrayref will be considered a
2117 logical false and will generate 0=1.
2119 =head2 Tests for NULL values
2121 If the value part is C<undef> then this is converted to SQL <IS NULL>
2130 $stmt = "WHERE user = ? AND status IS NULL";
2133 To test if a column IS NOT NULL:
2137 status => { '!=', undef },
2140 =head2 Specific comparison operators
2142 If you want to specify a different type of operator for your comparison,
2143 you can use a hashref for a given column:
2147 status => { '!=', 'completed' }
2150 Which would generate:
2152 $stmt = "WHERE user = ? AND status != ?";
2153 @bind = ('nwiger', 'completed');
2155 To test against multiple values, just enclose the values in an arrayref:
2157 status => { '=', ['assigned', 'in-progress', 'pending'] };
2159 Which would give you:
2161 "WHERE status = ? OR status = ? OR status = ?"
2164 The hashref can also contain multiple pairs, in which case it is expanded
2165 into an C<AND> of its elements:
2169 status => { '!=', 'completed', -not_like => 'pending%' }
2172 # Or more dynamically, like from a form
2173 $where{user} = 'nwiger';
2174 $where{status}{'!='} = 'completed';
2175 $where{status}{'-not_like'} = 'pending%';
2177 # Both generate this
2178 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2179 @bind = ('nwiger', 'completed', 'pending%');
2182 To get an OR instead, you can combine it with the arrayref idea:
2186 priority => [ { '=', 2 }, { '>', 5 } ]
2189 Which would generate:
2191 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2192 @bind = ('2', '5', 'nwiger');
2194 If you want to include literal SQL (with or without bind values), just use a
2195 scalar reference or reference to an arrayref as the value:
2198 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2199 date_expires => { '<' => \"now()" }
2202 Which would generate:
2204 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2205 @bind = ('11/26/2008');
2208 =head2 Logic and nesting operators
2210 In the example above,
2211 there is a subtle trap if you want to say something like
2212 this (notice the C<AND>):
2214 WHERE priority != ? AND priority != ?
2216 Because, in Perl you I<can't> do this:
2218 priority => { '!=' => 2, '!=' => 1 }
2220 As the second C<!=> key will obliterate the first. The solution
2221 is to use the special C<-modifier> form inside an arrayref:
2223 priority => [ -and => {'!=', 2},
2227 Normally, these would be joined by C<OR>, but the modifier tells it
2228 to use C<AND> instead. (Hint: You can use this in conjunction with the
2229 C<logic> option to C<new()> in order to change the way your queries
2230 work by default.) B<Important:> Note that the C<-modifier> goes
2231 B<INSIDE> the arrayref, as an extra first element. This will
2232 B<NOT> do what you think it might:
2234 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2236 Here is a quick list of equivalencies, since there is some overlap:
2239 status => {'!=', 'completed', 'not like', 'pending%' }
2240 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2243 status => {'=', ['assigned', 'in-progress']}
2244 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2245 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2249 =head2 Special operators: IN, BETWEEN, etc.
2251 You can also use the hashref format to compare a list of fields using the
2252 C<IN> comparison operator, by specifying the list as an arrayref:
2255 status => 'completed',
2256 reportid => { -in => [567, 2335, 2] }
2259 Which would generate:
2261 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2262 @bind = ('completed', '567', '2335', '2');
2264 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2267 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2268 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2269 'sqltrue' (by default: C<1=1>).
2271 In addition to the array you can supply a chunk of literal sql or
2272 literal sql with bind:
2275 customer => { -in => \[
2276 'SELECT cust_id FROM cust WHERE balance > ?',
2279 status => { -in => \'SELECT status_codes FROM states' },
2285 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2286 AND status IN ( SELECT status_codes FROM states )
2290 Finally, if the argument to C<-in> is not a reference, it will be
2291 treated as a single-element array.
2293 Another pair of operators is C<-between> and C<-not_between>,
2294 used with an arrayref of two values:
2298 completion_date => {
2299 -not_between => ['2002-10-01', '2003-02-06']
2305 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2307 Just like with C<-in> all plausible combinations of literal SQL
2311 start0 => { -between => [ 1, 2 ] },
2312 start1 => { -between => \["? AND ?", 1, 2] },
2313 start2 => { -between => \"lower(x) AND upper(y)" },
2314 start3 => { -between => [
2316 \["upper(?)", 'stuff' ],
2323 ( start0 BETWEEN ? AND ? )
2324 AND ( start1 BETWEEN ? AND ? )
2325 AND ( start2 BETWEEN lower(x) AND upper(y) )
2326 AND ( start3 BETWEEN lower(x) AND upper(?) )
2328 @bind = (1, 2, 1, 2, 'stuff');
2331 These are the two builtin "special operators"; but the
2332 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2334 =head2 Unary operators: bool
2336 If you wish to test against boolean columns or functions within your
2337 database you can use the C<-bool> and C<-not_bool> operators. For
2338 example to test the column C<is_user> being true and the column
2339 C<is_enabled> being false you would use:-
2343 -not_bool => 'is_enabled',
2348 WHERE is_user AND NOT is_enabled
2350 If a more complex combination is required, testing more conditions,
2351 then you should use the and/or operators:-
2356 -not_bool => { two=> { -rlike => 'bar' } },
2357 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2368 (NOT ( three = ? OR three > ? ))
2371 =head2 Nested conditions, -and/-or prefixes
2373 So far, we've seen how multiple conditions are joined with a top-level
2374 C<AND>. We can change this by putting the different conditions we want in
2375 hashes and then putting those hashes in an array. For example:
2380 status => { -like => ['pending%', 'dispatched'] },
2384 status => 'unassigned',
2388 This data structure would create the following:
2390 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2391 OR ( user = ? AND status = ? ) )";
2392 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2395 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2396 to change the logic inside:
2402 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2403 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2410 $stmt = "WHERE ( user = ?
2411 AND ( ( workhrs > ? AND geo = ? )
2412 OR ( workhrs < ? OR geo = ? ) ) )";
2413 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2415 =head3 Algebraic inconsistency, for historical reasons
2417 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2418 operator goes C<outside> of the nested structure; whereas when connecting
2419 several constraints on one column, the C<-and> operator goes
2420 C<inside> the arrayref. Here is an example combining both features:
2423 -and => [a => 1, b => 2],
2424 -or => [c => 3, d => 4],
2425 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2430 WHERE ( ( ( a = ? AND b = ? )
2431 OR ( c = ? OR d = ? )
2432 OR ( e LIKE ? AND e LIKE ? ) ) )
2434 This difference in syntax is unfortunate but must be preserved for
2435 historical reasons. So be careful: the two examples below would
2436 seem algebraically equivalent, but they are not
2439 { -like => 'foo%' },
2440 { -like => '%bar' },
2442 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2445 { col => { -like => 'foo%' } },
2446 { col => { -like => '%bar' } },
2448 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2451 =head2 Literal SQL and value type operators
2453 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2454 side" is a column name and the "right side" is a value (normally rendered as
2455 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2456 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2457 alter this behavior. There are several ways of doing so.
2461 This is a virtual operator that signals the string to its right side is an
2462 identifier (a column name) and not a value. For example to compare two
2463 columns you would write:
2466 priority => { '<', 2 },
2467 requestor => { -ident => 'submitter' },
2472 $stmt = "WHERE priority < ? AND requestor = submitter";
2475 If you are maintaining legacy code you may see a different construct as
2476 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2481 This is a virtual operator that signals that the construct to its right side
2482 is a value to be passed to DBI. This is for example necessary when you want
2483 to write a where clause against an array (for RDBMS that support such
2484 datatypes). For example:
2487 array => { -value => [1, 2, 3] }
2492 $stmt = 'WHERE array = ?';
2493 @bind = ([1, 2, 3]);
2495 Note that if you were to simply say:
2501 the result would probably not be what you wanted:
2503 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2508 Finally, sometimes only literal SQL will do. To include a random snippet
2509 of SQL verbatim, you specify it as a scalar reference. Consider this only
2510 as a last resort. Usually there is a better way. For example:
2513 priority => { '<', 2 },
2514 requestor => { -in => \'(SELECT name FROM hitmen)' },
2519 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2522 Note that in this example, you only get one bind parameter back, since
2523 the verbatim SQL is passed as part of the statement.
2527 Never use untrusted input as a literal SQL argument - this is a massive
2528 security risk (there is no way to check literal snippets for SQL
2529 injections and other nastyness). If you need to deal with untrusted input
2530 use literal SQL with placeholders as described next.
2532 =head3 Literal SQL with placeholders and bind values (subqueries)
2534 If the literal SQL to be inserted has placeholders and bind values,
2535 use a reference to an arrayref (yes this is a double reference --
2536 not so common, but perfectly legal Perl). For example, to find a date
2537 in Postgres you can use something like this:
2540 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2545 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2548 Note that you must pass the bind values in the same format as they are returned
2549 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2550 to C<columns>, you must provide the bind values in the
2551 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2552 scalar value; most commonly the column name, but you can use any scalar value
2553 (including references and blessed references), L<SQL::Abstract> will simply
2554 pass it through intact. So if C<bindtype> is set to C<columns> the above
2555 example will look like:
2558 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2561 Literal SQL is especially useful for nesting parenthesized clauses in the
2562 main SQL query. Here is a first example:
2564 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2568 bar => \["IN ($sub_stmt)" => @sub_bind],
2573 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2574 WHERE c2 < ? AND c3 LIKE ?))";
2575 @bind = (1234, 100, "foo%");
2577 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2578 are expressed in the same way. Of course the C<$sub_stmt> and
2579 its associated bind values can be generated through a former call
2582 my ($sub_stmt, @sub_bind)
2583 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2584 c3 => {-like => "foo%"}});
2587 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2590 In the examples above, the subquery was used as an operator on a column;
2591 but the same principle also applies for a clause within the main C<%where>
2592 hash, like an EXISTS subquery:
2594 my ($sub_stmt, @sub_bind)
2595 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2596 my %where = ( -and => [
2598 \["EXISTS ($sub_stmt)" => @sub_bind],
2603 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2604 WHERE c1 = ? AND c2 > t0.c0))";
2608 Observe that the condition on C<c2> in the subquery refers to
2609 column C<t0.c0> of the main query: this is I<not> a bind
2610 value, so we have to express it through a scalar ref.
2611 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2612 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2613 what we wanted here.
2615 Finally, here is an example where a subquery is used
2616 for expressing unary negation:
2618 my ($sub_stmt, @sub_bind)
2619 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2620 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2622 lname => {like => '%son%'},
2623 \["NOT ($sub_stmt)" => @sub_bind],
2628 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2629 @bind = ('%son%', 10, 20)
2631 =head3 Deprecated usage of Literal SQL
2633 Below are some examples of archaic use of literal SQL. It is shown only as
2634 reference for those who deal with legacy code. Each example has a much
2635 better, cleaner and safer alternative that users should opt for in new code.
2641 my %where = ( requestor => \'IS NOT NULL' )
2643 $stmt = "WHERE requestor IS NOT NULL"
2645 This used to be the way of generating NULL comparisons, before the handling
2646 of C<undef> got formalized. For new code please use the superior syntax as
2647 described in L</Tests for NULL values>.
2651 my %where = ( requestor => \'= submitter' )
2653 $stmt = "WHERE requestor = submitter"
2655 This used to be the only way to compare columns. Use the superior L</-ident>
2656 method for all new code. For example an identifier declared in such a way
2657 will be properly quoted if L</quote_char> is properly set, while the legacy
2658 form will remain as supplied.
2662 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2664 $stmt = "WHERE completed > ? AND is_ready"
2665 @bind = ('2012-12-21')
2667 Using an empty string literal used to be the only way to express a boolean.
2668 For all new code please use the much more readable
2669 L<-bool|/Unary operators: bool> operator.
2675 These pages could go on for a while, since the nesting of the data
2676 structures this module can handle are pretty much unlimited (the
2677 module implements the C<WHERE> expansion as a recursive function
2678 internally). Your best bet is to "play around" with the module a
2679 little to see how the data structures behave, and choose the best
2680 format for your data based on that.
2682 And of course, all the values above will probably be replaced with
2683 variables gotten from forms or the command line. After all, if you
2684 knew everything ahead of time, you wouldn't have to worry about
2685 dynamically-generating SQL and could just hardwire it into your
2688 =head1 ORDER BY CLAUSES
2690 Some functions take an order by clause. This can either be a scalar (just a
2691 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2692 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2695 Given | Will Generate
2696 ---------------------------------------------------------------
2698 'colA' | ORDER BY colA
2700 [qw/colA colB/] | ORDER BY colA, colB
2702 {-asc => 'colA'} | ORDER BY colA ASC
2704 {-desc => 'colB'} | ORDER BY colB DESC
2706 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2708 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2710 \'colA DESC' | ORDER BY colA DESC
2712 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2713 | /* ...with $x bound to ? */
2716 { -asc => 'colA' }, | colA ASC,
2717 { -desc => [qw/colB/] }, | colB DESC,
2718 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2719 \'colE DESC', | colE DESC,
2720 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2721 ] | /* ...with $x bound to ? */
2722 ===============================================================
2726 =head1 SPECIAL OPERATORS
2728 my $sqlmaker = SQL::Abstract->new(special_ops => [
2732 my ($self, $field, $op, $arg) = @_;
2738 handler => 'method_name',
2742 A "special operator" is a SQL syntactic clause that can be
2743 applied to a field, instead of a usual binary operator.
2746 WHERE field IN (?, ?, ?)
2747 WHERE field BETWEEN ? AND ?
2748 WHERE MATCH(field) AGAINST (?, ?)
2750 Special operators IN and BETWEEN are fairly standard and therefore
2751 are builtin within C<SQL::Abstract> (as the overridable methods
2752 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2753 like the MATCH .. AGAINST example above which is specific to MySQL,
2754 you can write your own operator handlers - supply a C<special_ops>
2755 argument to the C<new> method. That argument takes an arrayref of
2756 operator definitions; each operator definition is a hashref with two
2763 the regular expression to match the operator
2767 Either a coderef or a plain scalar method name. In both cases
2768 the expected return is C<< ($sql, @bind) >>.
2770 When supplied with a method name, it is simply called on the
2771 L<SQL::Abstract> object as:
2773 $self->$method_name($field, $op, $arg)
2777 $field is the LHS of the operator
2778 $op is the part that matched the handler regex
2781 When supplied with a coderef, it is called as:
2783 $coderef->($self, $field, $op, $arg)
2788 For example, here is an implementation
2789 of the MATCH .. AGAINST syntax for MySQL
2791 my $sqlmaker = SQL::Abstract->new(special_ops => [
2793 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2794 {regex => qr/^match$/i,
2796 my ($self, $field, $op, $arg) = @_;
2797 $arg = [$arg] if not ref $arg;
2798 my $label = $self->_quote($field);
2799 my ($placeholder) = $self->_convert('?');
2800 my $placeholders = join ", ", (($placeholder) x @$arg);
2801 my $sql = $self->_sqlcase('match') . " ($label) "
2802 . $self->_sqlcase('against') . " ($placeholders) ";
2803 my @bind = $self->_bindtype($field, @$arg);
2804 return ($sql, @bind);
2811 =head1 UNARY OPERATORS
2813 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2817 my ($self, $op, $arg) = @_;
2823 handler => 'method_name',
2827 A "unary operator" is a SQL syntactic clause that can be
2828 applied to a field - the operator goes before the field
2830 You can write your own operator handlers - supply a C<unary_ops>
2831 argument to the C<new> method. That argument takes an arrayref of
2832 operator definitions; each operator definition is a hashref with two
2839 the regular expression to match the operator
2843 Either a coderef or a plain scalar method name. In both cases
2844 the expected return is C<< $sql >>.
2846 When supplied with a method name, it is simply called on the
2847 L<SQL::Abstract> object as:
2849 $self->$method_name($op, $arg)
2853 $op is the part that matched the handler regex
2854 $arg is the RHS or argument of the operator
2856 When supplied with a coderef, it is called as:
2858 $coderef->($self, $op, $arg)
2866 Thanks to some benchmarking by Mark Stosberg, it turns out that
2867 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2868 I must admit this wasn't an intentional design issue, but it's a
2869 byproduct of the fact that you get to control your C<DBI> handles
2872 To maximize performance, use a code snippet like the following:
2874 # prepare a statement handle using the first row
2875 # and then reuse it for the rest of the rows
2877 for my $href (@array_of_hashrefs) {
2878 $stmt ||= $sql->insert('table', $href);
2879 $sth ||= $dbh->prepare($stmt);
2880 $sth->execute($sql->values($href));
2883 The reason this works is because the keys in your C<$href> are sorted
2884 internally by B<SQL::Abstract>. Thus, as long as your data retains
2885 the same structure, you only have to generate the SQL the first time
2886 around. On subsequent queries, simply use the C<values> function provided
2887 by this module to return your values in the correct order.
2889 However this depends on the values having the same type - if, for
2890 example, the values of a where clause may either have values
2891 (resulting in sql of the form C<column = ?> with a single bind
2892 value), or alternatively the values might be C<undef> (resulting in
2893 sql of the form C<column IS NULL> with no bind value) then the
2894 caching technique suggested will not work.
2898 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2899 really like this part (I do, at least). Building up a complex query
2900 can be as simple as the following:
2907 use CGI::FormBuilder;
2910 my $form = CGI::FormBuilder->new(...);
2911 my $sql = SQL::Abstract->new;
2913 if ($form->submitted) {
2914 my $field = $form->field;
2915 my $id = delete $field->{id};
2916 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2919 Of course, you would still have to connect using C<DBI> to run the
2920 query, but the point is that if you make your form look like your
2921 table, the actual query script can be extremely simplistic.
2923 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2924 a fast interface to returning and formatting data. I frequently
2925 use these three modules together to write complex database query
2926 apps in under 50 lines.
2928 =head1 HOW TO CONTRIBUTE
2930 Contributions are always welcome, in all usable forms (we especially
2931 welcome documentation improvements). The delivery methods include git-
2932 or unified-diff formatted patches, GitHub pull requests, or plain bug
2933 reports either via RT or the Mailing list. Contributors are generally
2934 granted full access to the official repository after their first several
2935 patches pass successful review.
2937 This project is maintained in a git repository. The code and related tools are
2938 accessible at the following locations:
2942 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2944 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2946 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2948 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2954 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2955 Great care has been taken to preserve the I<published> behavior
2956 documented in previous versions in the 1.* family; however,
2957 some features that were previously undocumented, or behaved
2958 differently from the documentation, had to be changed in order
2959 to clarify the semantics. Hence, client code that was relying
2960 on some dark areas of C<SQL::Abstract> v1.*
2961 B<might behave differently> in v1.50.
2963 The main changes are:
2969 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2973 support for the { operator => \"..." } construct (to embed literal SQL)
2977 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2981 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2985 defensive programming: check arguments
2989 fixed bug with global logic, which was previously implemented
2990 through global variables yielding side-effects. Prior versions would
2991 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2992 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2993 Now this is interpreted
2994 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2999 fixed semantics of _bindtype on array args
3003 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3004 we just avoid shifting arrays within that tree.
3008 dropped the C<_modlogic> function
3012 =head1 ACKNOWLEDGEMENTS
3014 There are a number of individuals that have really helped out with
3015 this module. Unfortunately, most of them submitted bugs via CPAN
3016 so I have no idea who they are! But the people I do know are:
3018 Ash Berlin (order_by hash term support)
3019 Matt Trout (DBIx::Class support)
3020 Mark Stosberg (benchmarking)
3021 Chas Owens (initial "IN" operator support)
3022 Philip Collins (per-field SQL functions)
3023 Eric Kolve (hashref "AND" support)
3024 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3025 Dan Kubb (support for "quote_char" and "name_sep")
3026 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3027 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3028 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3029 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3030 Oliver Charles (support for "RETURNING" after "INSERT")
3036 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3040 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3042 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3044 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3045 While not an official support venue, C<DBIx::Class> makes heavy use of
3046 C<SQL::Abstract>, and as such list members there are very familiar with
3047 how to create queries.
3051 This module is free software; you may copy this under the same
3052 terms as perl itself (either the GNU General Public License or
3053 the Artistic License)