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 $opt{user_special_ops} = [ @{$opt{special_ops} ||= []} ];
159 # regexes are applied in order, thus push after user-defines
160 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
163 $opt{unary_ops} ||= [];
165 # rudimentary sanity-check for user supplied bits treated as functions/operators
166 # If a purported function matches this regular expression, an exception is thrown.
167 # Literal SQL is *NOT* subject to this check, only functions (and column names
168 # when quoting is not in effect)
171 # need to guard against ()'s in column names too, but this will break tons of
172 # hacks... ideas anyone?
173 $opt{injection_guard} ||= qr/
179 return bless \%opt, $class;
182 sub sqltrue { +{ -literal => [ $_[0]->{sqltrue} ] } }
183 sub sqlfalse { +{ -literal => [ $_[0]->{sqlfalse} ] } }
185 sub _assert_pass_injection_guard {
186 if ($_[1] =~ $_[0]->{injection_guard}) {
187 my $class = ref $_[0];
188 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
189 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
190 . "{injection_guard} attribute to ${class}->new()"
195 #======================================================================
197 #======================================================================
201 my $table = $self->_table(shift);
202 my $data = shift || return;
205 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
206 my ($sql, @bind) = $self->$method($data);
207 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
209 if ($options->{returning}) {
210 my ($s, @b) = $self->_insert_returning($options);
215 return wantarray ? ($sql, @bind) : $sql;
218 # So that subclasses can override INSERT ... RETURNING separately from
219 # UPDATE and DELETE (e.g. DBIx::Class::SQLMaker::Oracle does this)
220 sub _insert_returning { shift->_returning(@_) }
223 my ($self, $options) = @_;
225 my $f = $options->{returning};
227 my ($sql, @bind) = $self->_render_expr(
228 $self->_expand_maybe_list_expr($f, undef, -ident)
231 ? $self->_sqlcase(' returning ') . $sql
232 : ($self->_sqlcase(' returning ').$sql, @bind);
235 sub _insert_HASHREF { # explicit list of fields and then values
236 my ($self, $data) = @_;
238 my @fields = sort keys %$data;
240 my ($sql, @bind) = $self->_insert_values($data);
243 $_ = $self->_quote($_) foreach @fields;
244 $sql = "( ".join(", ", @fields).") ".$sql;
246 return ($sql, @bind);
249 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
250 my ($self, $data) = @_;
252 # no names (arrayref) so can't generate bindtype
253 $self->{bindtype} ne 'columns'
254 or belch "can't do 'columns' bindtype when called with arrayref";
256 my (@values, @all_bind);
257 foreach my $value (@$data) {
258 my ($values, @bind) = $self->_insert_value(undef, $value);
259 push @values, $values;
260 push @all_bind, @bind;
262 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
263 return ($sql, @all_bind);
266 sub _insert_ARRAYREFREF { # literal SQL with bind
267 my ($self, $data) = @_;
269 my ($sql, @bind) = @${$data};
270 $self->_assert_bindval_matches_bindtype(@bind);
272 return ($sql, @bind);
276 sub _insert_SCALARREF { # literal SQL without bind
277 my ($self, $data) = @_;
283 my ($self, $data) = @_;
285 my (@values, @all_bind);
286 foreach my $column (sort keys %$data) {
287 my ($values, @bind) = $self->_insert_value($column, $data->{$column});
288 push @values, $values;
289 push @all_bind, @bind;
291 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
292 return ($sql, @all_bind);
296 my ($self, $column, $v) = @_;
298 return $self->_render_expr(
299 $self->_expand_insert_value($column, $v)
303 sub _expand_insert_value {
304 my ($self, $column, $v) = @_;
306 if (ref($v) eq 'ARRAY') {
307 if ($self->{array_datatypes}) {
308 return +{ -bind => [ $column, $v ] };
310 my ($sql, @bind) = @$v;
311 $self->_assert_bindval_matches_bindtype(@bind);
312 return +{ -literal => $v };
314 if (ref($v) eq 'HASH') {
315 if (grep !/^-/, keys %$v) {
316 belch "HASH ref as bind value in insert is not supported";
317 return +{ -bind => [ $column, $v ] };
321 return +{ -bind => [ $column, undef ] };
323 local our $Cur_Col_Meta = $column;
324 return $self->_expand_expr($v);
329 #======================================================================
331 #======================================================================
336 my $table = $self->_table(shift);
337 my $data = shift || return;
341 # first build the 'SET' part of the sql statement
342 puke "Unsupported data type specified to \$sql->update"
343 unless ref $data eq 'HASH';
345 my ($sql, @all_bind) = $self->_update_set_values($data);
346 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
350 my($where_sql, @where_bind) = $self->where($where);
352 push @all_bind, @where_bind;
355 if ($options->{returning}) {
356 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
357 $sql .= $returning_sql;
358 push @all_bind, @returning_bind;
361 return wantarray ? ($sql, @all_bind) : $sql;
364 sub _update_set_values {
365 my ($self, $data) = @_;
367 return $self->_render_expr(
368 $self->_expand_update_set_values($data),
372 sub _expand_update_set_values {
373 my ($self, $data) = @_;
374 $self->_expand_maybe_list_expr( [
377 +{ -op => [ '=', { -ident => $k }, $set ] };
383 ? ($self->{array_datatypes}
384 ? [ $k, +{ -bind => [ $k, $v ] } ]
385 : [ $k, +{ -literal => $v } ])
387 local our $Cur_Col_Meta = $k;
388 [ $k, $self->_expand_expr($v) ]
395 # So that subclasses can override UPDATE ... RETURNING separately from
397 sub _update_returning { shift->_returning(@_) }
401 #======================================================================
403 #======================================================================
408 my $table = $self->_table(shift);
409 my $fields = shift || '*';
413 my ($fields_sql, @bind) = $self->_select_fields($fields);
415 my ($where_sql, @where_bind) = $self->where($where, $order);
416 push @bind, @where_bind;
418 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
419 $self->_sqlcase('from'), $table)
422 return wantarray ? ($sql, @bind) : $sql;
426 my ($self, $fields) = @_;
427 return $self->_render_expr(
428 $self->_expand_maybe_list_expr($fields, undef, '-ident')
432 #======================================================================
434 #======================================================================
439 my $table = $self->_table(shift);
443 my($where_sql, @bind) = $self->where($where);
444 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
446 if ($options->{returning}) {
447 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
448 $sql .= $returning_sql;
449 push @bind, @returning_bind;
452 return wantarray ? ($sql, @bind) : $sql;
455 # So that subclasses can override DELETE ... RETURNING separately from
457 sub _delete_returning { shift->_returning(@_) }
461 #======================================================================
463 #======================================================================
467 # Finally, a separate routine just to handle WHERE clauses
469 my ($self, $where, $order) = @_;
471 local $self->{convert_where} = $self->{convert};
474 my ($sql, @bind) = defined($where)
475 ? $self->_recurse_where($where)
477 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
481 my ($order_sql, @order_bind) = $self->_order_by($order);
483 push @bind, @order_bind;
486 return wantarray ? ($sql, @bind) : $sql;
490 my ($self, $expr, $logic, $default_scalar_to) = @_;
491 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
492 return undef unless defined($expr);
493 if (ref($expr) eq 'HASH') {
494 if (keys %$expr > 1) {
498 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
502 return unless %$expr;
503 return $self->_expand_expr_hashpair(%$expr, $logic);
505 if (ref($expr) eq 'ARRAY') {
506 my $logic = lc($logic || $self->{logic});
507 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
513 while (my ($el) = splice @expr, 0, 1) {
514 puke "Supplying an empty left hand side argument is not supported in array-pairs"
515 unless defined($el) and length($el);
516 my $elref = ref($el);
518 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
519 } elsif ($elref eq 'ARRAY') {
520 push(@res, $self->_expand_expr($el)) if @$el;
521 } elsif (my $l = is_literal_value($el)) {
522 push @res, { -literal => $l };
523 } elsif ($elref eq 'HASH') {
524 push @res, $self->_expand_expr($el);
529 return { -op => [ $logic, @res ] };
531 if (my $literal = is_literal_value($expr)) {
532 return +{ -literal => $literal };
534 if (!ref($expr) or Scalar::Util::blessed($expr)) {
535 if (my $d = $Default_Scalar_To) {
536 return +{ $d => $expr };
538 if (my $m = our $Cur_Col_Meta) {
539 return +{ -bind => [ $m, $expr ] };
541 return +{ -value => $expr };
546 sub _expand_expr_hashpair {
547 my ($self, $k, $v, $logic) = @_;
548 unless (defined($k) and length($k)) {
549 if (defined($k) and my $literal = is_literal_value($v)) {
550 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
551 return { -literal => $literal };
553 puke "Supplying an empty left hand side argument is not supported";
556 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
557 if ($k =~ s/ [_\s]? \d+ $//x ) {
558 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
559 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
562 return $self->_expand_expr($v);
566 return $self->_expand_expr($v);
568 puke "-bool => undef not supported" unless defined($v);
569 return { -ident => $v };
572 return { -op => [ 'not', $self->_expand_expr($v) ] };
574 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
577 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
580 if (my ($logic) = $k =~ /^-(and|or)$/i) {
581 if (ref($v) eq 'HASH') {
582 return $self->_expand_expr($v, $logic);
584 if (ref($v) eq 'ARRAY') {
585 return $self->_expand_expr($v, $logic);
590 $op =~ s/^-// if length($op) > 1;
592 # top level special ops are illegal in general
593 puke "Illegal use of top-level '-$op'"
594 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
596 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
597 return +{ -bind => [ $m, $v ] };
599 if ($k eq '-op' or $k eq '-ident' or $k eq '-value' or $k eq '-bind' or $k eq '-literal' or $k eq '-func') {
602 if (my $custom = $self->{custom_expansions}{($k =~ /^-(.*)$/)[0]}) {
603 return $self->$custom($v);
608 and (keys %$v)[0] =~ /^-/
610 my ($func) = $k =~ /^-(.*)$/;
611 return +{ -func => [ $func, $self->_expand_expr($v) ] };
613 if (!ref($v) or is_literal_value($v)) {
614 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
621 and exists $v->{-value}
622 and not defined $v->{-value}
625 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
627 if (!ref($v) or Scalar::Util::blessed($v)) {
632 { -bind => [ $k, $v ] }
636 if (ref($v) eq 'HASH') {
640 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
647 $self->_assert_pass_injection_guard($vk);
648 if ($vk =~ s/ [_\s]? \d+ $//x ) {
649 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
650 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
652 if ($vk =~ /^(?:not[ _])?between$/) {
653 local our $Cur_Col_Meta = $k;
654 my @rhs = map $self->_expand_expr($_),
655 ref($vv) eq 'ARRAY' ? @$vv : $vv;
657 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
659 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
661 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
664 join(' ', split '_', $vk),
669 if ($vk =~ /^(?:not[ _])?in$/) {
670 if (my $literal = is_literal_value($vv)) {
671 my ($sql, @bind) = @$literal;
672 my $opened_sql = $self->_open_outer_paren($sql);
674 $vk, { -ident => $k },
675 [ { -literal => [ $opened_sql, @bind ] } ]
679 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
680 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
681 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
682 . 'will emit the logically correct SQL instead of raising this exception)'
684 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
686 my @rhs = map $self->_expand_expr($_),
687 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
688 map { defined($_) ? $_: puke($undef_err) }
689 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
690 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
693 join(' ', split '_', $vk),
698 if ($vk eq 'ident') {
699 if (! defined $vv or ref $vv) {
700 puke "-$vk requires a single plain scalar argument (a quotable identifier)";
708 if ($vk eq 'value') {
709 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
713 { -bind => [ $k, $vv ] }
716 if ($vk =~ /^is(?:[ _]not)?$/) {
717 puke "$vk can only take undef as argument"
721 and exists($vv->{-value})
722 and !defined($vv->{-value})
725 return +{ -op => [ $vk.' null', { -ident => $k } ] };
727 if ($vk =~ /^(and|or)$/) {
728 if (ref($vv) eq 'HASH') {
731 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
736 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{user_special_ops}}) {
737 return { -op => [ $vk, { -ident => $k }, $vv ] };
739 if (ref($vv) eq 'ARRAY') {
740 my ($logic, @values) = (
741 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
746 $vk =~ $self->{inequality_op}
747 or join(' ', split '_', $vk) =~ $self->{not_like_op}
749 if (lc($logic) eq '-or' and @values > 1) {
750 my $op = uc join ' ', split '_', $vk;
751 belch "A multi-element arrayref as an argument to the inequality op '$op' "
752 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
753 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
758 # try to DWIM on equality operators
759 my $op = join ' ', split '_', $vk;
761 $op =~ $self->{equality_op} ? $self->sqlfalse
762 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
763 : $op =~ $self->{inequality_op} ? $self->sqltrue
764 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
765 : puke "operator '$op' applied on an empty array (field '$k')";
769 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
777 and exists $vv->{-value}
778 and not defined $vv->{-value}
781 my $op = join ' ', split '_', $vk;
783 $op =~ /^not$/i ? 'is not' # legacy
784 : $op =~ $self->{equality_op} ? 'is'
785 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
786 : $op =~ $self->{inequality_op} ? 'is not'
787 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
788 : puke "unexpected operator '$op' with undef operand";
789 return +{ -op => [ $is.' null', { -ident => $k } ] };
791 local our $Cur_Col_Meta = $k;
795 $self->_expand_expr($vv)
798 if (ref($v) eq 'ARRAY') {
799 return $self->sqlfalse unless @$v;
800 $self->_debug("ARRAY($k) means distribute over elements");
802 $v->[0] =~ /^-((?:and|or))$/i
803 ? ($v = [ @{$v}[1..$#$v] ], $1)
804 : ($self->{logic} || 'or')
808 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
811 if (my $literal = is_literal_value($v)) {
813 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
816 my ($sql, @bind) = @$literal;
817 if ($self->{bindtype} eq 'columns') {
819 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
820 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
824 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
830 my ($self, $expr) = @_;
831 my ($k, $v, @rest) = %$expr;
833 my %op = map +("-$_" => '_render_'.$_),
834 qw(op func value bind ident literal);
835 if (my $meth = $op{$k}) {
836 return $self->$meth($v);
838 die "notreached: $k";
842 my ($self, $where, $logic) = @_;
844 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
846 my $where_exp = $self->_expand_expr($where, $logic);
848 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
850 # dispatch on appropriate method according to refkind of $where
851 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
853 # my ($sql, @bind) = $self->$method($where_exp, $logic);
855 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
857 # DBIx::Class used to call _recurse_where in scalar context
858 # something else might too...
860 return ($sql, @bind);
863 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
869 my ($self, $ident) = @_;
871 return $self->_convert($self->_quote($ident));
875 my ($self, $value) = @_;
877 return ($self->_convert('?'), $self->_bindtype(undef, $value));
880 my %unop_postfix = map +($_ => 1),
881 'is null', 'is not null',
889 my ($self, $args) = @_;
890 my ($left, $low, $high) = @$args;
891 my ($rhsql, @rhbind) = do {
893 puke "Single arg to between must be a literal"
894 unless $low->{-literal};
897 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
898 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
899 @{$l}[1..$#$l], @{$h}[1..$#$h])
902 my ($lhsql, @lhbind) = $self->_render_expr($left);
904 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
908 }), 'between', 'not between'),
912 my ($self, $args) = @_;
913 my ($lhs, $rhs) = @$args;
916 my ($sql, @bind) = $self->_render_expr($_);
917 push @in_bind, @bind;
920 my ($lhsql, @lbind) = $self->_render_expr($lhs);
922 $lhsql.' '.$self->_sqlcase($op).' ( '
933 my ($op, @args) = @$v;
934 $op =~ s/^-// if length($op) > 1;
936 if (my $h = $special{$op}) {
937 return $self->$h(\@args);
939 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{user_special_ops}}) {
940 puke "Special op '${op}' requires first value to be identifier"
941 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
942 return $self->${\($us->{handler})}($k, $op, $args[1]);
944 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
945 if (@args == 1 and $op !~ /^(and|or)$/) {
946 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
947 my $op_sql = $self->_sqlcase($final_op);
949 $unop_postfix{lc($final_op)}
950 ? "${expr_sql} ${op_sql}"
951 : "${op_sql} ${expr_sql}"
953 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
955 my @parts = map [ $self->_render_expr($_) ], @args;
956 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
957 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
962 map @{$_}[1..$#$_], @parts
969 my ($self, $rest) = @_;
970 my ($func, @args) = @$rest;
974 push @arg_sql, shift @x;
976 } map [ $self->_render_expr($_) ], @args;
977 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
981 my ($self, $bind) = @_;
982 return ($self->_convert('?'), $self->_bindtype(@$bind));
985 sub _render_literal {
986 my ($self, $literal) = @_;
987 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
991 # Some databases (SQLite) treat col IN (1, 2) different from
992 # col IN ( (1, 2) ). Use this to strip all outer parens while
993 # adding them back in the corresponding method
994 sub _open_outer_paren {
995 my ($self, $sql) = @_;
997 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
999 # there are closing parens inside, need the heavy duty machinery
1000 # to reevaluate the extraction starting from $sql (full reevaluation)
1001 if ($inner =~ /\)/) {
1002 require Text::Balanced;
1004 my (undef, $remainder) = do {
1005 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1007 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1010 # the entire expression needs to be a balanced bracketed thing
1011 # (after an extract no remainder sans trailing space)
1012 last if defined $remainder and $remainder =~ /\S/;
1022 #======================================================================
1024 #======================================================================
1027 my ($self, $arg) = @_;
1029 return '' unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1031 my $expander = sub {
1032 my ($self, $dir, $expr) = @_;
1033 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1034 map $self->_expand_expr($_, undef, -ident),
1035 ref($expr) eq 'ARRAY' ? @$expr : $expr;
1036 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1039 local $self->{custom_expansions} = {
1040 asc => sub { shift->$expander(asc => @_) },
1041 desc => sub { shift->$expander(desc => @_) },
1044 my $expanded = $self->$expander(undef, $arg);
1046 my ($sql, @bind) = $self->_render_expr($expanded);
1048 my $final_sql = $self->_sqlcase(' order by ').$sql;
1050 return wantarray ? ($final_sql, @bind) : $final_sql;
1053 #======================================================================
1054 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1055 #======================================================================
1060 ($self->_render_expr(
1061 $self->_expand_maybe_list_expr($from, undef, -ident)
1066 #======================================================================
1068 #======================================================================
1070 sub _expand_maybe_list_expr {
1071 my ($self, $expr, $logic, $default) = @_;
1073 if (ref($expr) eq 'ARRAY') {
1075 ',', map $self->_expand_expr($_, $logic, $default), @$expr
1082 return $self->_expand_expr($e, $logic, $default);
1085 # highly optimized, as it's called way too often
1087 # my ($self, $label) = @_;
1089 return '' unless defined $_[1];
1090 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1091 puke 'Identifier cannot be hashref' if ref($_[1]) eq 'HASH';
1093 unless ($_[0]->{quote_char}) {
1094 if (ref($_[1]) eq 'ARRAY') {
1095 return join($_[0]->{name_sep}||'.', @{$_[1]});
1097 $_[0]->_assert_pass_injection_guard($_[1]);
1102 my $qref = ref $_[0]->{quote_char};
1104 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1105 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1106 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1108 my $esc = $_[0]->{escape_char} || $r;
1110 # parts containing * are naturally unquoted
1112 $_[0]->{name_sep}||'',
1116 : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r }
1118 (ref($_[1]) eq 'ARRAY'
1122 ? split (/\Q$_[0]->{name_sep}\E/, $_[1] )
1130 # Conversion, if applicable
1132 #my ($self, $arg) = @_;
1133 if ($_[0]->{convert_where}) {
1134 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1141 #my ($self, $col, @vals) = @_;
1142 # called often - tighten code
1143 return $_[0]->{bindtype} eq 'columns'
1144 ? map {[$_[1], $_]} @_[2 .. $#_]
1149 # Dies if any element of @bind is not in [colname => value] format
1150 # if bindtype is 'columns'.
1151 sub _assert_bindval_matches_bindtype {
1152 # my ($self, @bind) = @_;
1154 if ($self->{bindtype} eq 'columns') {
1156 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1157 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1163 sub _join_sql_clauses {
1164 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1166 if (@$clauses_aref > 1) {
1167 my $join = " " . $self->_sqlcase($logic) . " ";
1168 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1169 return ($sql, @$bind_aref);
1171 elsif (@$clauses_aref) {
1172 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1175 return (); # if no SQL, ignore @$bind_aref
1180 # Fix SQL case, if so requested
1182 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1183 # don't touch the argument ... crooked logic, but let's not change it!
1184 return $_[0]->{case} ? $_[1] : uc($_[1]);
1188 #======================================================================
1189 # DISPATCHING FROM REFKIND
1190 #======================================================================
1193 my ($self, $data) = @_;
1195 return 'UNDEF' unless defined $data;
1197 # blessed objects are treated like scalars
1198 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1200 return 'SCALAR' unless $ref;
1203 while ($ref eq 'REF') {
1205 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1209 return ($ref||'SCALAR') . ('REF' x $n_steps);
1213 my ($self, $data) = @_;
1214 my @try = ($self->_refkind($data));
1215 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1216 push @try, 'FALLBACK';
1220 sub _METHOD_FOR_refkind {
1221 my ($self, $meth_prefix, $data) = @_;
1224 for (@{$self->_try_refkind($data)}) {
1225 $method = $self->can($meth_prefix."_".$_)
1229 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1233 sub _SWITCH_refkind {
1234 my ($self, $data, $dispatch_table) = @_;
1237 for (@{$self->_try_refkind($data)}) {
1238 $coderef = $dispatch_table->{$_}
1242 puke "no dispatch entry for ".$self->_refkind($data)
1251 #======================================================================
1252 # VALUES, GENERATE, AUTOLOAD
1253 #======================================================================
1255 # LDNOTE: original code from nwiger, didn't touch code in that section
1256 # I feel the AUTOLOAD stuff should not be the default, it should
1257 # only be activated on explicit demand by user.
1261 my $data = shift || return;
1262 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1263 unless ref $data eq 'HASH';
1266 foreach my $k (sort keys %$data) {
1267 my $v = $data->{$k};
1268 $self->_SWITCH_refkind($v, {
1270 if ($self->{array_datatypes}) { # array datatype
1271 push @all_bind, $self->_bindtype($k, $v);
1273 else { # literal SQL with bind
1274 my ($sql, @bind) = @$v;
1275 $self->_assert_bindval_matches_bindtype(@bind);
1276 push @all_bind, @bind;
1279 ARRAYREFREF => sub { # literal SQL with bind
1280 my ($sql, @bind) = @${$v};
1281 $self->_assert_bindval_matches_bindtype(@bind);
1282 push @all_bind, @bind;
1284 SCALARREF => sub { # literal SQL without bind
1286 SCALAR_or_UNDEF => sub {
1287 push @all_bind, $self->_bindtype($k, $v);
1298 my(@sql, @sqlq, @sqlv);
1302 if ($ref eq 'HASH') {
1303 for my $k (sort keys %$_) {
1306 my $label = $self->_quote($k);
1307 if ($r eq 'ARRAY') {
1308 # literal SQL with bind
1309 my ($sql, @bind) = @$v;
1310 $self->_assert_bindval_matches_bindtype(@bind);
1311 push @sqlq, "$label = $sql";
1313 } elsif ($r eq 'SCALAR') {
1314 # literal SQL without bind
1315 push @sqlq, "$label = $$v";
1317 push @sqlq, "$label = ?";
1318 push @sqlv, $self->_bindtype($k, $v);
1321 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1322 } elsif ($ref eq 'ARRAY') {
1323 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1326 if ($r eq 'ARRAY') { # literal SQL with bind
1327 my ($sql, @bind) = @$v;
1328 $self->_assert_bindval_matches_bindtype(@bind);
1331 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1332 # embedded literal SQL
1339 push @sql, '(' . join(', ', @sqlq) . ')';
1340 } elsif ($ref eq 'SCALAR') {
1344 # strings get case twiddled
1345 push @sql, $self->_sqlcase($_);
1349 my $sql = join ' ', @sql;
1351 # this is pretty tricky
1352 # if ask for an array, return ($stmt, @bind)
1353 # otherwise, s/?/shift @sqlv/ to put it inline
1355 return ($sql, @sqlv);
1357 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1358 ref $d ? $d->[1] : $d/e;
1367 # This allows us to check for a local, then _form, attr
1369 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1370 return $self->generate($name, @_);
1381 SQL::Abstract - Generate SQL from Perl data structures
1387 my $sql = SQL::Abstract->new;
1389 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1391 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1393 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1395 my($stmt, @bind) = $sql->delete($table, \%where);
1397 # Then, use these in your DBI statements
1398 my $sth = $dbh->prepare($stmt);
1399 $sth->execute(@bind);
1401 # Just generate the WHERE clause
1402 my($stmt, @bind) = $sql->where(\%where, $order);
1404 # Return values in the same order, for hashed queries
1405 # See PERFORMANCE section for more details
1406 my @bind = $sql->values(\%fieldvals);
1410 This module was inspired by the excellent L<DBIx::Abstract>.
1411 However, in using that module I found that what I really wanted
1412 to do was generate SQL, but still retain complete control over my
1413 statement handles and use the DBI interface. So, I set out to
1414 create an abstract SQL generation module.
1416 While based on the concepts used by L<DBIx::Abstract>, there are
1417 several important differences, especially when it comes to WHERE
1418 clauses. I have modified the concepts used to make the SQL easier
1419 to generate from Perl data structures and, IMO, more intuitive.
1420 The underlying idea is for this module to do what you mean, based
1421 on the data structures you provide it. The big advantage is that
1422 you don't have to modify your code every time your data changes,
1423 as this module figures it out.
1425 To begin with, an SQL INSERT is as easy as just specifying a hash
1426 of C<key=value> pairs:
1429 name => 'Jimbo Bobson',
1430 phone => '123-456-7890',
1431 address => '42 Sister Lane',
1432 city => 'St. Louis',
1433 state => 'Louisiana',
1436 The SQL can then be generated with this:
1438 my($stmt, @bind) = $sql->insert('people', \%data);
1440 Which would give you something like this:
1442 $stmt = "INSERT INTO people
1443 (address, city, name, phone, state)
1444 VALUES (?, ?, ?, ?, ?)";
1445 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1446 '123-456-7890', 'Louisiana');
1448 These are then used directly in your DBI code:
1450 my $sth = $dbh->prepare($stmt);
1451 $sth->execute(@bind);
1453 =head2 Inserting and Updating Arrays
1455 If your database has array types (like for example Postgres),
1456 activate the special option C<< array_datatypes => 1 >>
1457 when creating the C<SQL::Abstract> object.
1458 Then you may use an arrayref to insert and update database array types:
1460 my $sql = SQL::Abstract->new(array_datatypes => 1);
1462 planets => [qw/Mercury Venus Earth Mars/]
1465 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1469 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1471 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1474 =head2 Inserting and Updating SQL
1476 In order to apply SQL functions to elements of your C<%data> you may
1477 specify a reference to an arrayref for the given hash value. For example,
1478 if you need to execute the Oracle C<to_date> function on a value, you can
1479 say something like this:
1483 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1486 The first value in the array is the actual SQL. Any other values are
1487 optional and would be included in the bind values array. This gives
1490 my($stmt, @bind) = $sql->insert('people', \%data);
1492 $stmt = "INSERT INTO people (name, date_entered)
1493 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1494 @bind = ('Bill', '03/02/2003');
1496 An UPDATE is just as easy, all you change is the name of the function:
1498 my($stmt, @bind) = $sql->update('people', \%data);
1500 Notice that your C<%data> isn't touched; the module will generate
1501 the appropriately quirky SQL for you automatically. Usually you'll
1502 want to specify a WHERE clause for your UPDATE, though, which is
1503 where handling C<%where> hashes comes in handy...
1505 =head2 Complex where statements
1507 This module can generate pretty complicated WHERE statements
1508 easily. For example, simple C<key=value> pairs are taken to mean
1509 equality, and if you want to see if a field is within a set
1510 of values, you can use an arrayref. Let's say we wanted to
1511 SELECT some data based on this criteria:
1514 requestor => 'inna',
1515 worker => ['nwiger', 'rcwe', 'sfz'],
1516 status => { '!=', 'completed' }
1519 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1521 The above would give you something like this:
1523 $stmt = "SELECT * FROM tickets WHERE
1524 ( requestor = ? ) AND ( status != ? )
1525 AND ( worker = ? OR worker = ? OR worker = ? )";
1526 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1528 Which you could then use in DBI code like so:
1530 my $sth = $dbh->prepare($stmt);
1531 $sth->execute(@bind);
1537 The methods are simple. There's one for every major SQL operation,
1538 and a constructor you use first. The arguments are specified in a
1539 similar order for each method (table, then fields, then a where
1540 clause) to try and simplify things.
1542 =head2 new(option => 'value')
1544 The C<new()> function takes a list of options and values, and returns
1545 a new B<SQL::Abstract> object which can then be used to generate SQL
1546 through the methods below. The options accepted are:
1552 If set to 'lower', then SQL will be generated in all lowercase. By
1553 default SQL is generated in "textbook" case meaning something like:
1555 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1557 Any setting other than 'lower' is ignored.
1561 This determines what the default comparison operator is. By default
1562 it is C<=>, meaning that a hash like this:
1564 %where = (name => 'nwiger', email => 'nate@wiger.org');
1566 Will generate SQL like this:
1568 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1570 However, you may want loose comparisons by default, so if you set
1571 C<cmp> to C<like> you would get SQL such as:
1573 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1575 You can also override the comparison on an individual basis - see
1576 the huge section on L</"WHERE CLAUSES"> at the bottom.
1578 =item sqltrue, sqlfalse
1580 Expressions for inserting boolean values within SQL statements.
1581 By default these are C<1=1> and C<1=0>. They are used
1582 by the special operators C<-in> and C<-not_in> for generating
1583 correct SQL even when the argument is an empty array (see below).
1587 This determines the default logical operator for multiple WHERE
1588 statements in arrays or hashes. If absent, the default logic is "or"
1589 for arrays, and "and" for hashes. This means that a WHERE
1593 event_date => {'>=', '2/13/99'},
1594 event_date => {'<=', '4/24/03'},
1597 will generate SQL like this:
1599 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1601 This is probably not what you want given this query, though (look
1602 at the dates). To change the "OR" to an "AND", simply specify:
1604 my $sql = SQL::Abstract->new(logic => 'and');
1606 Which will change the above C<WHERE> to:
1608 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1610 The logic can also be changed locally by inserting
1611 a modifier in front of an arrayref:
1613 @where = (-and => [event_date => {'>=', '2/13/99'},
1614 event_date => {'<=', '4/24/03'} ]);
1616 See the L</"WHERE CLAUSES"> section for explanations.
1620 This will automatically convert comparisons using the specified SQL
1621 function for both column and value. This is mostly used with an argument
1622 of C<upper> or C<lower>, so that the SQL will have the effect of
1623 case-insensitive "searches". For example, this:
1625 $sql = SQL::Abstract->new(convert => 'upper');
1626 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1628 Will turn out the following SQL:
1630 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1632 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1633 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1634 not validate this option; it will just pass through what you specify verbatim).
1638 This is a kludge because many databases suck. For example, you can't
1639 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1640 Instead, you have to use C<bind_param()>:
1642 $sth->bind_param(1, 'reg data');
1643 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1645 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1646 which loses track of which field each slot refers to. Fear not.
1648 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1649 Currently, you can specify either C<normal> (default) or C<columns>. If you
1650 specify C<columns>, you will get an array that looks like this:
1652 my $sql = SQL::Abstract->new(bindtype => 'columns');
1653 my($stmt, @bind) = $sql->insert(...);
1656 [ 'column1', 'value1' ],
1657 [ 'column2', 'value2' ],
1658 [ 'column3', 'value3' ],
1661 You can then iterate through this manually, using DBI's C<bind_param()>.
1663 $sth->prepare($stmt);
1666 my($col, $data) = @$_;
1667 if ($col eq 'details' || $col eq 'comments') {
1668 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1669 } elsif ($col eq 'image') {
1670 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1672 $sth->bind_param($i, $data);
1676 $sth->execute; # execute without @bind now
1678 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1679 Basically, the advantage is still that you don't have to care which fields
1680 are or are not included. You could wrap that above C<for> loop in a simple
1681 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1682 get a layer of abstraction over manual SQL specification.
1684 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1685 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1686 will expect the bind values in this format.
1690 This is the character that a table or column name will be quoted
1691 with. By default this is an empty string, but you could set it to
1692 the character C<`>, to generate SQL like this:
1694 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1696 Alternatively, you can supply an array ref of two items, the first being the left
1697 hand quote character, and the second the right hand quote character. For
1698 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1699 that generates SQL like this:
1701 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1703 Quoting is useful if you have tables or columns names that are reserved
1704 words in your database's SQL dialect.
1708 This is the character that will be used to escape L</quote_char>s appearing
1709 in an identifier before it has been quoted.
1711 The parameter default in case of a single L</quote_char> character is the quote
1714 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1715 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1716 of the B<opening (left)> L</quote_char> within the identifier are currently left
1717 untouched. The default for opening-closing-style quotes may change in future
1718 versions, thus you are B<strongly encouraged> to specify the escape character
1723 This is the character that separates a table and column name. It is
1724 necessary to specify this when the C<quote_char> option is selected,
1725 so that tables and column names can be individually quoted like this:
1727 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1729 =item injection_guard
1731 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1732 column name specified in a query structure. This is a safety mechanism to avoid
1733 injection attacks when mishandling user input e.g.:
1735 my %condition_as_column_value_pairs = get_values_from_user();
1736 $sqla->select( ... , \%condition_as_column_value_pairs );
1738 If the expression matches an exception is thrown. Note that literal SQL
1739 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1741 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1743 =item array_datatypes
1745 When this option is true, arrayrefs in INSERT or UPDATE are
1746 interpreted as array datatypes and are passed directly
1748 When this option is false, arrayrefs are interpreted
1749 as literal SQL, just like refs to arrayrefs
1750 (but this behavior is for backwards compatibility; when writing
1751 new queries, use the "reference to arrayref" syntax
1757 Takes a reference to a list of "special operators"
1758 to extend the syntax understood by L<SQL::Abstract>.
1759 See section L</"SPECIAL OPERATORS"> for details.
1763 Takes a reference to a list of "unary operators"
1764 to extend the syntax understood by L<SQL::Abstract>.
1765 See section L</"UNARY OPERATORS"> for details.
1771 =head2 insert($table, \@values || \%fieldvals, \%options)
1773 This is the simplest function. You simply give it a table name
1774 and either an arrayref of values or hashref of field/value pairs.
1775 It returns an SQL INSERT statement and a list of bind values.
1776 See the sections on L</"Inserting and Updating Arrays"> and
1777 L</"Inserting and Updating SQL"> for information on how to insert
1778 with those data types.
1780 The optional C<\%options> hash reference may contain additional
1781 options to generate the insert SQL. Currently supported options
1788 Takes either a scalar of raw SQL fields, or an array reference of
1789 field names, and adds on an SQL C<RETURNING> statement at the end.
1790 This allows you to return data generated by the insert statement
1791 (such as row IDs) without performing another C<SELECT> statement.
1792 Note, however, this is not part of the SQL standard and may not
1793 be supported by all database engines.
1797 =head2 update($table, \%fieldvals, \%where, \%options)
1799 This takes a table, hashref of field/value pairs, and an optional
1800 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1802 See the sections on L</"Inserting and Updating Arrays"> and
1803 L</"Inserting and Updating SQL"> for information on how to insert
1804 with those data types.
1806 The optional C<\%options> hash reference may contain additional
1807 options to generate the update SQL. Currently supported options
1814 See the C<returning> option to
1815 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1819 =head2 select($source, $fields, $where, $order)
1821 This returns a SQL SELECT statement and associated list of bind values, as
1822 specified by the arguments:
1828 Specification of the 'FROM' part of the statement.
1829 The argument can be either a plain scalar (interpreted as a table
1830 name, will be quoted), or an arrayref (interpreted as a list
1831 of table names, joined by commas, quoted), or a scalarref
1832 (literal SQL, not quoted).
1836 Specification of the list of fields to retrieve from
1838 The argument can be either an arrayref (interpreted as a list
1839 of field names, will be joined by commas and quoted), or a
1840 plain scalar (literal SQL, not quoted).
1841 Please observe that this API is not as flexible as that of
1842 the first argument C<$source>, for backwards compatibility reasons.
1846 Optional argument to specify the WHERE part of the query.
1847 The argument is most often a hashref, but can also be
1848 an arrayref or plain scalar --
1849 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1853 Optional argument to specify the ORDER BY part of the query.
1854 The argument can be a scalar, a hashref or an arrayref
1855 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1861 =head2 delete($table, \%where, \%options)
1863 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1864 It returns an SQL DELETE statement and list of bind values.
1866 The optional C<\%options> hash reference may contain additional
1867 options to generate the delete SQL. Currently supported options
1874 See the C<returning> option to
1875 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1879 =head2 where(\%where, $order)
1881 This is used to generate just the WHERE clause. For example,
1882 if you have an arbitrary data structure and know what the
1883 rest of your SQL is going to look like, but want an easy way
1884 to produce a WHERE clause, use this. It returns an SQL WHERE
1885 clause and list of bind values.
1888 =head2 values(\%data)
1890 This just returns the values from the hash C<%data>, in the same
1891 order that would be returned from any of the other above queries.
1892 Using this allows you to markedly speed up your queries if you
1893 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1895 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1897 Warning: This is an experimental method and subject to change.
1899 This returns arbitrarily generated SQL. It's a really basic shortcut.
1900 It will return two different things, depending on return context:
1902 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1903 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1905 These would return the following:
1907 # First calling form
1908 $stmt = "CREATE TABLE test (?, ?)";
1909 @bind = (field1, field2);
1911 # Second calling form
1912 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1914 Depending on what you're trying to do, it's up to you to choose the correct
1915 format. In this example, the second form is what you would want.
1919 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1923 ALTER SESSION SET nls_date_format = 'MM/YY'
1925 You get the idea. Strings get their case twiddled, but everything
1926 else remains verbatim.
1928 =head1 EXPORTABLE FUNCTIONS
1930 =head2 is_plain_value
1932 Determines if the supplied argument is a plain value as understood by this
1937 =item * The value is C<undef>
1939 =item * The value is a non-reference
1941 =item * The value is an object with stringification overloading
1943 =item * The value is of the form C<< { -value => $anything } >>
1947 On failure returns C<undef>, on success returns a B<scalar> reference
1948 to the original supplied argument.
1954 The stringification overloading detection is rather advanced: it takes
1955 into consideration not only the presence of a C<""> overload, but if that
1956 fails also checks for enabled
1957 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1958 on either C<0+> or C<bool>.
1960 Unfortunately testing in the field indicates that this
1961 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1962 but only when very large numbers of stringifying objects are involved.
1963 At the time of writing ( Sep 2014 ) there is no clear explanation of
1964 the direct cause, nor is there a manageably small test case that reliably
1965 reproduces the problem.
1967 If you encounter any of the following exceptions in B<random places within
1968 your application stack> - this module may be to blame:
1970 Operation "ne": no method found,
1971 left argument in overloaded package <something>,
1972 right argument in overloaded package <something>
1976 Stub found while resolving method "???" overloading """" in package <something>
1978 If you fall victim to the above - please attempt to reduce the problem
1979 to something that could be sent to the L<SQL::Abstract developers
1980 |DBIx::Class/GETTING HELP/SUPPORT>
1981 (either publicly or privately). As a workaround in the meantime you can
1982 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
1983 value, which will most likely eliminate your problem (at the expense of
1984 not being able to properly detect exotic forms of stringification).
1986 This notice and environment variable will be removed in a future version,
1987 as soon as the underlying problem is found and a reliable workaround is
1992 =head2 is_literal_value
1994 Determines if the supplied argument is a literal value as understood by this
1999 =item * C<\$sql_string>
2001 =item * C<\[ $sql_string, @bind_values ]>
2005 On failure returns C<undef>, on success returns an B<array> reference
2006 containing the unpacked version of the supplied literal SQL and bind values.
2008 =head1 WHERE CLAUSES
2012 This module uses a variation on the idea from L<DBIx::Abstract>. It
2013 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2014 module is that things in arrays are OR'ed, and things in hashes
2017 The easiest way to explain is to show lots of examples. After
2018 each C<%where> hash shown, it is assumed you used:
2020 my($stmt, @bind) = $sql->where(\%where);
2022 However, note that the C<%where> hash can be used directly in any
2023 of the other functions as well, as described above.
2025 =head2 Key-value pairs
2027 So, let's get started. To begin, a simple hash:
2031 status => 'completed'
2034 Is converted to SQL C<key = val> statements:
2036 $stmt = "WHERE user = ? AND status = ?";
2037 @bind = ('nwiger', 'completed');
2039 One common thing I end up doing is having a list of values that
2040 a field can be in. To do this, simply specify a list inside of
2045 status => ['assigned', 'in-progress', 'pending'];
2048 This simple code will create the following:
2050 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2051 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2053 A field associated to an empty arrayref will be considered a
2054 logical false and will generate 0=1.
2056 =head2 Tests for NULL values
2058 If the value part is C<undef> then this is converted to SQL <IS NULL>
2067 $stmt = "WHERE user = ? AND status IS NULL";
2070 To test if a column IS NOT NULL:
2074 status => { '!=', undef },
2077 =head2 Specific comparison operators
2079 If you want to specify a different type of operator for your comparison,
2080 you can use a hashref for a given column:
2084 status => { '!=', 'completed' }
2087 Which would generate:
2089 $stmt = "WHERE user = ? AND status != ?";
2090 @bind = ('nwiger', 'completed');
2092 To test against multiple values, just enclose the values in an arrayref:
2094 status => { '=', ['assigned', 'in-progress', 'pending'] };
2096 Which would give you:
2098 "WHERE status = ? OR status = ? OR status = ?"
2101 The hashref can also contain multiple pairs, in which case it is expanded
2102 into an C<AND> of its elements:
2106 status => { '!=', 'completed', -not_like => 'pending%' }
2109 # Or more dynamically, like from a form
2110 $where{user} = 'nwiger';
2111 $where{status}{'!='} = 'completed';
2112 $where{status}{'-not_like'} = 'pending%';
2114 # Both generate this
2115 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2116 @bind = ('nwiger', 'completed', 'pending%');
2119 To get an OR instead, you can combine it with the arrayref idea:
2123 priority => [ { '=', 2 }, { '>', 5 } ]
2126 Which would generate:
2128 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2129 @bind = ('2', '5', 'nwiger');
2131 If you want to include literal SQL (with or without bind values), just use a
2132 scalar reference or reference to an arrayref as the value:
2135 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2136 date_expires => { '<' => \"now()" }
2139 Which would generate:
2141 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2142 @bind = ('11/26/2008');
2145 =head2 Logic and nesting operators
2147 In the example above,
2148 there is a subtle trap if you want to say something like
2149 this (notice the C<AND>):
2151 WHERE priority != ? AND priority != ?
2153 Because, in Perl you I<can't> do this:
2155 priority => { '!=' => 2, '!=' => 1 }
2157 As the second C<!=> key will obliterate the first. The solution
2158 is to use the special C<-modifier> form inside an arrayref:
2160 priority => [ -and => {'!=', 2},
2164 Normally, these would be joined by C<OR>, but the modifier tells it
2165 to use C<AND> instead. (Hint: You can use this in conjunction with the
2166 C<logic> option to C<new()> in order to change the way your queries
2167 work by default.) B<Important:> Note that the C<-modifier> goes
2168 B<INSIDE> the arrayref, as an extra first element. This will
2169 B<NOT> do what you think it might:
2171 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2173 Here is a quick list of equivalencies, since there is some overlap:
2176 status => {'!=', 'completed', 'not like', 'pending%' }
2177 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2180 status => {'=', ['assigned', 'in-progress']}
2181 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2182 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2186 =head2 Special operators: IN, BETWEEN, etc.
2188 You can also use the hashref format to compare a list of fields using the
2189 C<IN> comparison operator, by specifying the list as an arrayref:
2192 status => 'completed',
2193 reportid => { -in => [567, 2335, 2] }
2196 Which would generate:
2198 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2199 @bind = ('completed', '567', '2335', '2');
2201 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2204 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2205 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2206 'sqltrue' (by default: C<1=1>).
2208 In addition to the array you can supply a chunk of literal sql or
2209 literal sql with bind:
2212 customer => { -in => \[
2213 'SELECT cust_id FROM cust WHERE balance > ?',
2216 status => { -in => \'SELECT status_codes FROM states' },
2222 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2223 AND status IN ( SELECT status_codes FROM states )
2227 Finally, if the argument to C<-in> is not a reference, it will be
2228 treated as a single-element array.
2230 Another pair of operators is C<-between> and C<-not_between>,
2231 used with an arrayref of two values:
2235 completion_date => {
2236 -not_between => ['2002-10-01', '2003-02-06']
2242 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2244 Just like with C<-in> all plausible combinations of literal SQL
2248 start0 => { -between => [ 1, 2 ] },
2249 start1 => { -between => \["? AND ?", 1, 2] },
2250 start2 => { -between => \"lower(x) AND upper(y)" },
2251 start3 => { -between => [
2253 \["upper(?)", 'stuff' ],
2260 ( start0 BETWEEN ? AND ? )
2261 AND ( start1 BETWEEN ? AND ? )
2262 AND ( start2 BETWEEN lower(x) AND upper(y) )
2263 AND ( start3 BETWEEN lower(x) AND upper(?) )
2265 @bind = (1, 2, 1, 2, 'stuff');
2268 These are the two builtin "special operators"; but the
2269 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2271 =head2 Unary operators: bool
2273 If you wish to test against boolean columns or functions within your
2274 database you can use the C<-bool> and C<-not_bool> operators. For
2275 example to test the column C<is_user> being true and the column
2276 C<is_enabled> being false you would use:-
2280 -not_bool => 'is_enabled',
2285 WHERE is_user AND NOT is_enabled
2287 If a more complex combination is required, testing more conditions,
2288 then you should use the and/or operators:-
2293 -not_bool => { two=> { -rlike => 'bar' } },
2294 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2305 (NOT ( three = ? OR three > ? ))
2308 =head2 Nested conditions, -and/-or prefixes
2310 So far, we've seen how multiple conditions are joined with a top-level
2311 C<AND>. We can change this by putting the different conditions we want in
2312 hashes and then putting those hashes in an array. For example:
2317 status => { -like => ['pending%', 'dispatched'] },
2321 status => 'unassigned',
2325 This data structure would create the following:
2327 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2328 OR ( user = ? AND status = ? ) )";
2329 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2332 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2333 to change the logic inside:
2339 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2340 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2347 $stmt = "WHERE ( user = ?
2348 AND ( ( workhrs > ? AND geo = ? )
2349 OR ( workhrs < ? OR geo = ? ) ) )";
2350 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2352 =head3 Algebraic inconsistency, for historical reasons
2354 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2355 operator goes C<outside> of the nested structure; whereas when connecting
2356 several constraints on one column, the C<-and> operator goes
2357 C<inside> the arrayref. Here is an example combining both features:
2360 -and => [a => 1, b => 2],
2361 -or => [c => 3, d => 4],
2362 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2367 WHERE ( ( ( a = ? AND b = ? )
2368 OR ( c = ? OR d = ? )
2369 OR ( e LIKE ? AND e LIKE ? ) ) )
2371 This difference in syntax is unfortunate but must be preserved for
2372 historical reasons. So be careful: the two examples below would
2373 seem algebraically equivalent, but they are not
2376 { -like => 'foo%' },
2377 { -like => '%bar' },
2379 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2382 { col => { -like => 'foo%' } },
2383 { col => { -like => '%bar' } },
2385 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2388 =head2 Literal SQL and value type operators
2390 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2391 side" is a column name and the "right side" is a value (normally rendered as
2392 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2393 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2394 alter this behavior. There are several ways of doing so.
2398 This is a virtual operator that signals the string to its right side is an
2399 identifier (a column name) and not a value. For example to compare two
2400 columns you would write:
2403 priority => { '<', 2 },
2404 requestor => { -ident => 'submitter' },
2409 $stmt = "WHERE priority < ? AND requestor = submitter";
2412 If you are maintaining legacy code you may see a different construct as
2413 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2418 This is a virtual operator that signals that the construct to its right side
2419 is a value to be passed to DBI. This is for example necessary when you want
2420 to write a where clause against an array (for RDBMS that support such
2421 datatypes). For example:
2424 array => { -value => [1, 2, 3] }
2429 $stmt = 'WHERE array = ?';
2430 @bind = ([1, 2, 3]);
2432 Note that if you were to simply say:
2438 the result would probably not be what you wanted:
2440 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2445 Finally, sometimes only literal SQL will do. To include a random snippet
2446 of SQL verbatim, you specify it as a scalar reference. Consider this only
2447 as a last resort. Usually there is a better way. For example:
2450 priority => { '<', 2 },
2451 requestor => { -in => \'(SELECT name FROM hitmen)' },
2456 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2459 Note that in this example, you only get one bind parameter back, since
2460 the verbatim SQL is passed as part of the statement.
2464 Never use untrusted input as a literal SQL argument - this is a massive
2465 security risk (there is no way to check literal snippets for SQL
2466 injections and other nastyness). If you need to deal with untrusted input
2467 use literal SQL with placeholders as described next.
2469 =head3 Literal SQL with placeholders and bind values (subqueries)
2471 If the literal SQL to be inserted has placeholders and bind values,
2472 use a reference to an arrayref (yes this is a double reference --
2473 not so common, but perfectly legal Perl). For example, to find a date
2474 in Postgres you can use something like this:
2477 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2482 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2485 Note that you must pass the bind values in the same format as they are returned
2486 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2487 to C<columns>, you must provide the bind values in the
2488 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2489 scalar value; most commonly the column name, but you can use any scalar value
2490 (including references and blessed references), L<SQL::Abstract> will simply
2491 pass it through intact. So if C<bindtype> is set to C<columns> the above
2492 example will look like:
2495 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2498 Literal SQL is especially useful for nesting parenthesized clauses in the
2499 main SQL query. Here is a first example:
2501 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2505 bar => \["IN ($sub_stmt)" => @sub_bind],
2510 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2511 WHERE c2 < ? AND c3 LIKE ?))";
2512 @bind = (1234, 100, "foo%");
2514 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2515 are expressed in the same way. Of course the C<$sub_stmt> and
2516 its associated bind values can be generated through a former call
2519 my ($sub_stmt, @sub_bind)
2520 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2521 c3 => {-like => "foo%"}});
2524 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2527 In the examples above, the subquery was used as an operator on a column;
2528 but the same principle also applies for a clause within the main C<%where>
2529 hash, like an EXISTS subquery:
2531 my ($sub_stmt, @sub_bind)
2532 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2533 my %where = ( -and => [
2535 \["EXISTS ($sub_stmt)" => @sub_bind],
2540 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2541 WHERE c1 = ? AND c2 > t0.c0))";
2545 Observe that the condition on C<c2> in the subquery refers to
2546 column C<t0.c0> of the main query: this is I<not> a bind
2547 value, so we have to express it through a scalar ref.
2548 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2549 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2550 what we wanted here.
2552 Finally, here is an example where a subquery is used
2553 for expressing unary negation:
2555 my ($sub_stmt, @sub_bind)
2556 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2557 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2559 lname => {like => '%son%'},
2560 \["NOT ($sub_stmt)" => @sub_bind],
2565 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2566 @bind = ('%son%', 10, 20)
2568 =head3 Deprecated usage of Literal SQL
2570 Below are some examples of archaic use of literal SQL. It is shown only as
2571 reference for those who deal with legacy code. Each example has a much
2572 better, cleaner and safer alternative that users should opt for in new code.
2578 my %where = ( requestor => \'IS NOT NULL' )
2580 $stmt = "WHERE requestor IS NOT NULL"
2582 This used to be the way of generating NULL comparisons, before the handling
2583 of C<undef> got formalized. For new code please use the superior syntax as
2584 described in L</Tests for NULL values>.
2588 my %where = ( requestor => \'= submitter' )
2590 $stmt = "WHERE requestor = submitter"
2592 This used to be the only way to compare columns. Use the superior L</-ident>
2593 method for all new code. For example an identifier declared in such a way
2594 will be properly quoted if L</quote_char> is properly set, while the legacy
2595 form will remain as supplied.
2599 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2601 $stmt = "WHERE completed > ? AND is_ready"
2602 @bind = ('2012-12-21')
2604 Using an empty string literal used to be the only way to express a boolean.
2605 For all new code please use the much more readable
2606 L<-bool|/Unary operators: bool> operator.
2612 These pages could go on for a while, since the nesting of the data
2613 structures this module can handle are pretty much unlimited (the
2614 module implements the C<WHERE> expansion as a recursive function
2615 internally). Your best bet is to "play around" with the module a
2616 little to see how the data structures behave, and choose the best
2617 format for your data based on that.
2619 And of course, all the values above will probably be replaced with
2620 variables gotten from forms or the command line. After all, if you
2621 knew everything ahead of time, you wouldn't have to worry about
2622 dynamically-generating SQL and could just hardwire it into your
2625 =head1 ORDER BY CLAUSES
2627 Some functions take an order by clause. This can either be a scalar (just a
2628 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2629 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2632 Given | Will Generate
2633 ---------------------------------------------------------------
2635 'colA' | ORDER BY colA
2637 [qw/colA colB/] | ORDER BY colA, colB
2639 {-asc => 'colA'} | ORDER BY colA ASC
2641 {-desc => 'colB'} | ORDER BY colB DESC
2643 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2645 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2647 \'colA DESC' | ORDER BY colA DESC
2649 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2650 | /* ...with $x bound to ? */
2653 { -asc => 'colA' }, | colA ASC,
2654 { -desc => [qw/colB/] }, | colB DESC,
2655 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2656 \'colE DESC', | colE DESC,
2657 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2658 ] | /* ...with $x bound to ? */
2659 ===============================================================
2663 =head1 SPECIAL OPERATORS
2665 my $sqlmaker = SQL::Abstract->new(special_ops => [
2669 my ($self, $field, $op, $arg) = @_;
2675 handler => 'method_name',
2679 A "special operator" is a SQL syntactic clause that can be
2680 applied to a field, instead of a usual binary operator.
2683 WHERE field IN (?, ?, ?)
2684 WHERE field BETWEEN ? AND ?
2685 WHERE MATCH(field) AGAINST (?, ?)
2687 Special operators IN and BETWEEN are fairly standard and therefore
2688 are builtin within C<SQL::Abstract> (as the overridable methods
2689 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2690 like the MATCH .. AGAINST example above which is specific to MySQL,
2691 you can write your own operator handlers - supply a C<special_ops>
2692 argument to the C<new> method. That argument takes an arrayref of
2693 operator definitions; each operator definition is a hashref with two
2700 the regular expression to match the operator
2704 Either a coderef or a plain scalar method name. In both cases
2705 the expected return is C<< ($sql, @bind) >>.
2707 When supplied with a method name, it is simply called on the
2708 L<SQL::Abstract> object as:
2710 $self->$method_name($field, $op, $arg)
2714 $field is the LHS of the operator
2715 $op is the part that matched the handler regex
2718 When supplied with a coderef, it is called as:
2720 $coderef->($self, $field, $op, $arg)
2725 For example, here is an implementation
2726 of the MATCH .. AGAINST syntax for MySQL
2728 my $sqlmaker = SQL::Abstract->new(special_ops => [
2730 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2731 {regex => qr/^match$/i,
2733 my ($self, $field, $op, $arg) = @_;
2734 $arg = [$arg] if not ref $arg;
2735 my $label = $self->_quote($field);
2736 my ($placeholder) = $self->_convert('?');
2737 my $placeholders = join ", ", (($placeholder) x @$arg);
2738 my $sql = $self->_sqlcase('match') . " ($label) "
2739 . $self->_sqlcase('against') . " ($placeholders) ";
2740 my @bind = $self->_bindtype($field, @$arg);
2741 return ($sql, @bind);
2748 =head1 UNARY OPERATORS
2750 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2754 my ($self, $op, $arg) = @_;
2760 handler => 'method_name',
2764 A "unary operator" is a SQL syntactic clause that can be
2765 applied to a field - the operator goes before the field
2767 You can write your own operator handlers - supply a C<unary_ops>
2768 argument to the C<new> method. That argument takes an arrayref of
2769 operator definitions; each operator definition is a hashref with two
2776 the regular expression to match the operator
2780 Either a coderef or a plain scalar method name. In both cases
2781 the expected return is C<< $sql >>.
2783 When supplied with a method name, it is simply called on the
2784 L<SQL::Abstract> object as:
2786 $self->$method_name($op, $arg)
2790 $op is the part that matched the handler regex
2791 $arg is the RHS or argument of the operator
2793 When supplied with a coderef, it is called as:
2795 $coderef->($self, $op, $arg)
2803 Thanks to some benchmarking by Mark Stosberg, it turns out that
2804 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2805 I must admit this wasn't an intentional design issue, but it's a
2806 byproduct of the fact that you get to control your C<DBI> handles
2809 To maximize performance, use a code snippet like the following:
2811 # prepare a statement handle using the first row
2812 # and then reuse it for the rest of the rows
2814 for my $href (@array_of_hashrefs) {
2815 $stmt ||= $sql->insert('table', $href);
2816 $sth ||= $dbh->prepare($stmt);
2817 $sth->execute($sql->values($href));
2820 The reason this works is because the keys in your C<$href> are sorted
2821 internally by B<SQL::Abstract>. Thus, as long as your data retains
2822 the same structure, you only have to generate the SQL the first time
2823 around. On subsequent queries, simply use the C<values> function provided
2824 by this module to return your values in the correct order.
2826 However this depends on the values having the same type - if, for
2827 example, the values of a where clause may either have values
2828 (resulting in sql of the form C<column = ?> with a single bind
2829 value), or alternatively the values might be C<undef> (resulting in
2830 sql of the form C<column IS NULL> with no bind value) then the
2831 caching technique suggested will not work.
2835 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2836 really like this part (I do, at least). Building up a complex query
2837 can be as simple as the following:
2844 use CGI::FormBuilder;
2847 my $form = CGI::FormBuilder->new(...);
2848 my $sql = SQL::Abstract->new;
2850 if ($form->submitted) {
2851 my $field = $form->field;
2852 my $id = delete $field->{id};
2853 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2856 Of course, you would still have to connect using C<DBI> to run the
2857 query, but the point is that if you make your form look like your
2858 table, the actual query script can be extremely simplistic.
2860 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2861 a fast interface to returning and formatting data. I frequently
2862 use these three modules together to write complex database query
2863 apps in under 50 lines.
2865 =head1 HOW TO CONTRIBUTE
2867 Contributions are always welcome, in all usable forms (we especially
2868 welcome documentation improvements). The delivery methods include git-
2869 or unified-diff formatted patches, GitHub pull requests, or plain bug
2870 reports either via RT or the Mailing list. Contributors are generally
2871 granted full access to the official repository after their first several
2872 patches pass successful review.
2874 This project is maintained in a git repository. The code and related tools are
2875 accessible at the following locations:
2879 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2881 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2883 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2885 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2891 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2892 Great care has been taken to preserve the I<published> behavior
2893 documented in previous versions in the 1.* family; however,
2894 some features that were previously undocumented, or behaved
2895 differently from the documentation, had to be changed in order
2896 to clarify the semantics. Hence, client code that was relying
2897 on some dark areas of C<SQL::Abstract> v1.*
2898 B<might behave differently> in v1.50.
2900 The main changes are:
2906 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2910 support for the { operator => \"..." } construct (to embed literal SQL)
2914 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2918 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2922 defensive programming: check arguments
2926 fixed bug with global logic, which was previously implemented
2927 through global variables yielding side-effects. Prior versions would
2928 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2929 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2930 Now this is interpreted
2931 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2936 fixed semantics of _bindtype on array args
2940 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2941 we just avoid shifting arrays within that tree.
2945 dropped the C<_modlogic> function
2949 =head1 ACKNOWLEDGEMENTS
2951 There are a number of individuals that have really helped out with
2952 this module. Unfortunately, most of them submitted bugs via CPAN
2953 so I have no idea who they are! But the people I do know are:
2955 Ash Berlin (order_by hash term support)
2956 Matt Trout (DBIx::Class support)
2957 Mark Stosberg (benchmarking)
2958 Chas Owens (initial "IN" operator support)
2959 Philip Collins (per-field SQL functions)
2960 Eric Kolve (hashref "AND" support)
2961 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2962 Dan Kubb (support for "quote_char" and "name_sep")
2963 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2964 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2965 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2966 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2967 Oliver Charles (support for "RETURNING" after "INSERT")
2973 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
2977 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
2979 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
2981 For support, your best bet is to try the C<DBIx::Class> users mailing list.
2982 While not an official support venue, C<DBIx::Class> makes heavy use of
2983 C<SQL::Abstract>, and as such list members there are very familiar with
2984 how to create queries.
2988 This module is free software; you may copy this under the same
2989 terms as perl itself (either the GNU General Public License or
2990 the Artistic License)