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 $fieldlist = $self->_SWITCH_refkind($f, {
228 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
229 SCALAR => sub {$self->_quote($f)},
230 SCALARREF => sub {$$f},
232 return $self->_sqlcase(' returning ') . $fieldlist;
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 my (@values, @all_bind);
299 $self->_SWITCH_refkind($v, {
302 if ($self->{array_datatypes}) { # if array datatype are activated
304 push @all_bind, $self->_bindtype($column, $v);
306 else { # else literal SQL with bind
307 my ($sql, @bind) = @$v;
308 $self->_assert_bindval_matches_bindtype(@bind);
310 push @all_bind, @bind;
314 ARRAYREFREF => sub { # literal SQL with bind
315 my ($sql, @bind) = @${$v};
316 $self->_assert_bindval_matches_bindtype(@bind);
318 push @all_bind, @bind;
321 # THINK: anything useful to do with a HASHREF ?
322 HASHREF => sub { # (nothing, but old SQLA passed it through)
323 #TODO in SQLA >= 2.0 it will die instead
324 belch "HASH ref as bind value in insert is not supported";
326 push @all_bind, $self->_bindtype($column, $v);
329 SCALARREF => sub { # literal SQL without bind
333 SCALAR_or_UNDEF => sub {
335 push @all_bind, $self->_bindtype($column, $v);
340 my $sql = join(", ", @values);
341 return ($sql, @all_bind);
346 #======================================================================
348 #======================================================================
353 my $table = $self->_table(shift);
354 my $data = shift || return;
358 # first build the 'SET' part of the sql statement
359 puke "Unsupported data type specified to \$sql->update"
360 unless ref $data eq 'HASH';
362 my ($sql, @all_bind) = $self->_update_set_values($data);
363 $sql = $self->_sqlcase('update ') . $table . $self->_sqlcase(' set ')
367 my($where_sql, @where_bind) = $self->where($where);
369 push @all_bind, @where_bind;
372 if ($options->{returning}) {
373 my ($returning_sql, @returning_bind) = $self->_update_returning($options);
374 $sql .= $returning_sql;
375 push @all_bind, @returning_bind;
378 return wantarray ? ($sql, @all_bind) : $sql;
381 sub _update_set_values {
382 my ($self, $data) = @_;
384 my (@set, @all_bind);
385 for my $k (sort keys %$data) {
388 my $label = $self->_quote($k);
390 $self->_SWITCH_refkind($v, {
392 if ($self->{array_datatypes}) { # array datatype
393 push @set, "$label = ?";
394 push @all_bind, $self->_bindtype($k, $v);
396 else { # literal SQL with bind
397 my ($sql, @bind) = @$v;
398 $self->_assert_bindval_matches_bindtype(@bind);
399 push @set, "$label = $sql";
400 push @all_bind, @bind;
403 ARRAYREFREF => sub { # literal SQL with bind
404 my ($sql, @bind) = @${$v};
405 $self->_assert_bindval_matches_bindtype(@bind);
406 push @set, "$label = $sql";
407 push @all_bind, @bind;
409 SCALARREF => sub { # literal SQL without bind
410 push @set, "$label = $$v";
413 my ($op, $arg, @rest) = %$v;
415 puke 'Operator calls in update must be in the form { -op => $arg }'
416 if (@rest or not $op =~ /^\-(.+)/);
418 local our $Cur_Col_Meta = $k;
419 my ($sql, @bind) = $self->_render_expr(
420 $self->_expand_expr_hashpair($op, $arg)
423 push @set, "$label = $sql";
424 push @all_bind, @bind;
426 SCALAR_or_UNDEF => sub {
427 push @set, "$label = ?";
428 push @all_bind, $self->_bindtype($k, $v);
434 my $sql = join ', ', @set;
436 return ($sql, @all_bind);
439 # So that subclasses can override UPDATE ... RETURNING separately from
441 sub _update_returning { shift->_returning(@_) }
445 #======================================================================
447 #======================================================================
452 my $table = $self->_table(shift);
453 my $fields = shift || '*';
457 my ($fields_sql, @bind) = $self->_select_fields($fields);
459 my ($where_sql, @where_bind) = $self->where($where, $order);
460 push @bind, @where_bind;
462 my $sql = join(' ', $self->_sqlcase('select'), $fields_sql,
463 $self->_sqlcase('from'), $table)
466 return wantarray ? ($sql, @bind) : $sql;
470 my ($self, $fields) = @_;
471 return ref $fields eq 'ARRAY' ? join ', ', map { $self->_quote($_) } @$fields
475 #======================================================================
477 #======================================================================
482 my $table = $self->_table(shift);
486 my($where_sql, @bind) = $self->where($where);
487 my $sql = $self->_sqlcase('delete from ') . $table . $where_sql;
489 if ($options->{returning}) {
490 my ($returning_sql, @returning_bind) = $self->_delete_returning($options);
491 $sql .= $returning_sql;
492 push @bind, @returning_bind;
495 return wantarray ? ($sql, @bind) : $sql;
498 # So that subclasses can override DELETE ... RETURNING separately from
500 sub _delete_returning { shift->_returning(@_) }
504 #======================================================================
506 #======================================================================
510 # Finally, a separate routine just to handle WHERE clauses
512 my ($self, $where, $order) = @_;
514 local $self->{convert_where} = $self->{convert};
517 my ($sql, @bind) = defined($where)
518 ? $self->_recurse_where($where)
520 $sql = (defined $sql and length $sql) ? $self->_sqlcase(' where ') . "( $sql )" : '';
524 my ($order_sql, @order_bind) = $self->_order_by($order);
526 push @bind, @order_bind;
529 return wantarray ? ($sql, @bind) : $sql;
533 my ($self, $expr, $logic, $default_scalar_to) = @_;
534 local our $Default_Scalar_To = $default_scalar_to if $default_scalar_to;
535 return undef unless defined($expr);
536 if (ref($expr) eq 'HASH') {
537 if (keys %$expr > 1) {
541 map $self->_expand_expr_hashpair($_ => $expr->{$_}, $logic),
545 return unless %$expr;
546 return $self->_expand_expr_hashpair(%$expr, $logic);
548 if (ref($expr) eq 'ARRAY') {
549 my $logic = lc($logic || $self->{logic});
550 $logic eq 'and' or $logic eq 'or' or puke "unknown logic: $logic";
556 while (my ($el) = splice @expr, 0, 1) {
557 puke "Supplying an empty left hand side argument is not supported in array-pairs"
558 unless defined($el) and length($el);
559 my $elref = ref($el);
561 push(@res, $self->_expand_expr({ $el, shift(@expr) }));
562 } elsif ($elref eq 'ARRAY') {
563 push(@res, $self->_expand_expr($el)) if @$el;
564 } elsif (my $l = is_literal_value($el)) {
565 push @res, { -literal => $l };
566 } elsif ($elref eq 'HASH') {
567 push @res, $self->_expand_expr($el);
572 return { -op => [ $logic, @res ] };
574 if (my $literal = is_literal_value($expr)) {
575 return +{ -literal => $literal };
577 if (!ref($expr) or Scalar::Util::blessed($expr)) {
578 if (my $d = $Default_Scalar_To) {
579 return +{ $d => $expr };
581 if (my $m = our $Cur_Col_Meta) {
582 return +{ -bind => [ $m, $expr ] };
584 return +{ -value => $expr };
589 sub _expand_expr_hashpair {
590 my ($self, $k, $v, $logic) = @_;
591 unless (defined($k) and length($k)) {
592 if (defined($k) and my $literal = is_literal_value($v)) {
593 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
594 return { -literal => $literal };
596 puke "Supplying an empty left hand side argument is not supported";
599 $self->_assert_pass_injection_guard($k =~ /^-(.*)$/s);
600 if ($k =~ s/ [_\s]? \d+ $//x ) {
601 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
602 . "You probably wanted ...-and => [ $k => COND1, $k => COND2 ... ]";
605 return $self->_expand_expr($v);
609 return $self->_expand_expr($v);
611 puke "-bool => undef not supported" unless defined($v);
612 return { -ident => $v };
615 return { -op => [ 'not', $self->_expand_expr($v) ] };
617 if (my ($rest) = $k =~/^-not[_ ](.*)$/) {
620 $self->_expand_expr_hashpair("-${rest}", $v, $logic)
623 if (my ($logic) = $k =~ /^-(and|or)$/i) {
624 if (ref($v) eq 'HASH') {
625 return $self->_expand_expr($v, $logic);
627 if (ref($v) eq 'ARRAY') {
628 return $self->_expand_expr($v, $logic);
633 $op =~ s/^-// if length($op) > 1;
635 # top level special ops are illegal in general
636 puke "Illegal use of top-level '-$op'"
637 if List::Util::first { $op =~ $_->{regex} } @{$self->{special_ops}};
639 if ($k eq '-value' and my $m = our $Cur_Col_Meta) {
640 return +{ -bind => [ $m, $v ] };
642 if ($k eq '-op' or $k eq '-ident' or $k eq '-value' or $k eq '-bind' or $k eq '-literal' or $k eq '-func') {
645 if (my $custom = $self->{custom_expansions}{($k =~ /^-(.*)$/)[0]}) {
646 return $self->$custom($v);
651 and (keys %$v)[0] =~ /^-/
653 my ($func) = $k =~ /^-(.*)$/;
654 return +{ -func => [ $func, $self->_expand_expr($v) ] };
656 if (!ref($v) or is_literal_value($v)) {
657 return +{ -op => [ $k =~ /^-(.*)$/, $self->_expand_expr($v) ] };
664 and exists $v->{-value}
665 and not defined $v->{-value}
668 return $self->_expand_expr_hashpair($k => { $self->{cmp} => undef });
670 if (!ref($v) or Scalar::Util::blessed($v)) {
675 { -bind => [ $k, $v ] }
679 if (ref($v) eq 'HASH') {
683 map $self->_expand_expr_hashpair($k => { $_ => $v->{$_} }),
690 $self->_assert_pass_injection_guard($vk);
691 if ($vk =~ s/ [_\s]? \d+ $//x ) {
692 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
693 . "You probably wanted ...-and => [ -$vk => COND1, -$vk => COND2 ... ]";
695 if ($vk =~ /^(?:not[ _])?between$/) {
696 local our $Cur_Col_Meta = $k;
697 my @rhs = map $self->_expand_expr($_),
698 ref($vv) eq 'ARRAY' ? @$vv : $vv;
700 (@rhs == 1 and ref($rhs[0]) eq 'HASH' and $rhs[0]->{-literal})
702 (@rhs == 2 and defined($rhs[0]) and defined($rhs[1]))
704 puke "Operator '${\uc($vk)}' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
707 join(' ', split '_', $vk),
712 if ($vk =~ /^(?:not[ _])?in$/) {
713 if (my $literal = is_literal_value($vv)) {
714 my ($sql, @bind) = @$literal;
715 my $opened_sql = $self->_open_outer_paren($sql);
717 $vk, { -ident => $k },
718 [ { -literal => [ $opened_sql, @bind ] } ]
722 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
723 . "-${\uc($vk)} operator was given an undef-containing list: !!!AUDIT YOUR CODE "
724 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
725 . 'will emit the logically correct SQL instead of raising this exception)'
727 puke("Argument passed to the '${\uc($vk)}' operator can not be undefined")
729 my @rhs = map $self->_expand_expr($_),
730 map { ref($_) ? $_ : { -bind => [ $k, $_ ] } }
731 map { defined($_) ? $_: puke($undef_err) }
732 (ref($vv) eq 'ARRAY' ? @$vv : $vv);
733 return $self->${\($vk =~ /^not/ ? 'sqltrue' : 'sqlfalse')} unless @rhs;
736 join(' ', split '_', $vk),
741 if ($vk eq 'ident') {
742 if (! defined $vv or ref $vv) {
743 puke "-$vk requires a single plain scalar argument (a quotable identifier)";
751 if ($vk eq 'value') {
752 return $self->_expand_expr_hashpair($k, undef) unless defined($vv);
756 { -bind => [ $k, $vv ] }
759 if ($vk =~ /^is(?:[ _]not)?$/) {
760 puke "$vk can only take undef as argument"
764 and exists($vv->{-value})
765 and !defined($vv->{-value})
768 return +{ -op => [ $vk.' null', { -ident => $k } ] };
770 if ($vk =~ /^(and|or)$/) {
771 if (ref($vv) eq 'HASH') {
774 map $self->_expand_expr_hashpair($k, { $_ => $vv->{$_} }),
779 if (my $us = List::Util::first { $vk =~ $_->{regex} } @{$self->{user_special_ops}}) {
780 return { -op => [ $vk, { -ident => $k }, $vv ] };
782 if (ref($vv) eq 'ARRAY') {
783 my ($logic, @values) = (
784 (defined($vv->[0]) and $vv->[0] =~ /^-(and|or)$/i)
789 $vk =~ $self->{inequality_op}
790 or join(' ', split '_', $vk) =~ $self->{not_like_op}
792 if (lc($logic) eq '-or' and @values > 1) {
793 my $op = uc join ' ', split '_', $vk;
794 belch "A multi-element arrayref as an argument to the inequality op '$op' "
795 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
796 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
801 # try to DWIM on equality operators
802 my $op = join ' ', split '_', $vk;
804 $op =~ $self->{equality_op} ? $self->sqlfalse
805 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqlfalse
806 : $op =~ $self->{inequality_op} ? $self->sqltrue
807 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->sqltrue
808 : puke "operator '$op' applied on an empty array (field '$k')";
812 map $self->_expand_expr_hashpair($k => { $vk => $_ }),
820 and exists $vv->{-value}
821 and not defined $vv->{-value}
824 my $op = join ' ', split '_', $vk;
826 $op =~ /^not$/i ? 'is not' # legacy
827 : $op =~ $self->{equality_op} ? 'is'
828 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
829 : $op =~ $self->{inequality_op} ? 'is not'
830 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
831 : puke "unexpected operator '$op' with undef operand";
832 return +{ -op => [ $is.' null', { -ident => $k } ] };
834 local our $Cur_Col_Meta = $k;
838 $self->_expand_expr($vv)
841 if (ref($v) eq 'ARRAY') {
842 return $self->sqlfalse unless @$v;
843 $self->_debug("ARRAY($k) means distribute over elements");
845 $v->[0] =~ /^-((?:and|or))$/i
846 ? ($v = [ @{$v}[1..$#$v] ], $1)
847 : ($self->{logic} || 'or')
851 map $self->_expand_expr({ $k => $_ }, $this_logic), @$v
854 if (my $literal = is_literal_value($v)) {
856 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
859 my ($sql, @bind) = @$literal;
860 if ($self->{bindtype} eq 'columns') {
862 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
863 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
867 return +{ -literal => [ $self->_quote($k).' '.$sql, @bind ] };
873 my ($self, $expr) = @_;
874 my ($k, $v, @rest) = %$expr;
876 my %op = map +("-$_" => '_render_'.$_),
877 qw(op func value bind ident literal);
878 if (my $meth = $op{$k}) {
879 return $self->$meth($v);
881 die "notreached: $k";
885 my ($self, $where, $logic) = @_;
887 #print STDERR Data::Dumper::Concise::Dumper([ $where, $logic ]);
889 my $where_exp = $self->_expand_expr($where, $logic);
891 #print STDERR Data::Dumper::Concise::Dumper([ EXP => $where_exp ]);
893 # dispatch on appropriate method according to refkind of $where
894 # my $method = $self->_METHOD_FOR_refkind("_where", $where_exp);
896 # my ($sql, @bind) = $self->$method($where_exp, $logic);
898 my ($sql, @bind) = defined($where_exp) ? $self->_render_expr($where_exp) : (undef);
900 # DBIx::Class used to call _recurse_where in scalar context
901 # something else might too...
903 return ($sql, @bind);
906 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
912 my ($self, $ident) = @_;
914 return $self->_convert($self->_quote($ident));
918 my ($self, $value) = @_;
920 return ($self->_convert('?'), $self->_bindtype(undef, $value));
923 my %unop_postfix = map +($_ => 1),
924 'is null', 'is not null',
932 my ($self, $args) = @_;
933 my ($left, $low, $high) = @$args;
934 my ($rhsql, @rhbind) = do {
936 puke "Single arg to between must be a literal"
937 unless $low->{-literal};
940 my ($l, $h) = map [ $self->_render_expr($_) ], $low, $high;
941 (join(' ', $l->[0], $self->_sqlcase('and'), $h->[0]),
942 @{$l}[1..$#$l], @{$h}[1..$#$h])
945 my ($lhsql, @lhbind) = $self->_render_expr($left);
947 join(' ', '(', $lhsql, $self->_sqlcase($op), $rhsql, ')'),
951 }), 'between', 'not between'),
955 my ($self, $args) = @_;
956 my ($lhs, $rhs) = @$args;
959 my ($sql, @bind) = $self->_render_expr($_);
960 push @in_bind, @bind;
963 my ($lhsql, @lbind) = $self->_render_expr($lhs);
965 $lhsql.' '.$self->_sqlcase($op).' ( '
976 my ($op, @args) = @$v;
977 $op =~ s/^-// if length($op) > 1;
979 if (my $h = $special{$op}) {
980 return $self->$h(\@args);
982 if (my $us = List::Util::first { $op =~ $_->{regex} } @{$self->{user_special_ops}}) {
983 puke "Special op '${op}' requires first value to be identifier"
984 unless my ($k) = map $_->{-ident}, grep ref($_) eq 'HASH', $args[0];
985 return $self->${\($us->{handler})}($k, $op, $args[1]);
987 my $final_op = $op =~ /^(?:is|not)_/ ? join(' ', split '_', $op) : $op;
988 if (@args == 1 and $op !~ /^(and|or)$/) {
989 my ($expr_sql, @bind) = $self->_render_expr($args[0]);
990 my $op_sql = $self->_sqlcase($final_op);
992 $unop_postfix{lc($final_op)}
993 ? "${expr_sql} ${op_sql}"
994 : "${op_sql} ${expr_sql}"
996 return (($op eq 'not' ? '('.$final_sql.')' : $final_sql), @bind);
998 my @parts = map [ $self->_render_expr($_) ], @args;
999 my ($final_sql) = map +($op =~ /^(and|or)$/ ? "(${_})" : $_), join(
1000 ($final_op eq ',' ? '' : ' ').$self->_sqlcase($final_op).' ',
1005 map @{$_}[1..$#$_], @parts
1012 my ($self, $rest) = @_;
1013 my ($func, @args) = @$rest;
1017 push @arg_sql, shift @x;
1019 } map [ $self->_render_expr($_) ], @args;
1020 return ($self->_sqlcase($func).'('.join(', ', @arg_sql).')', @bind);
1024 my ($self, $bind) = @_;
1025 return ($self->_convert('?'), $self->_bindtype(@$bind));
1028 sub _render_literal {
1029 my ($self, $literal) = @_;
1030 $self->_assert_bindval_matches_bindtype(@{$literal}[1..$#$literal]);
1034 # Some databases (SQLite) treat col IN (1, 2) different from
1035 # col IN ( (1, 2) ). Use this to strip all outer parens while
1036 # adding them back in the corresponding method
1037 sub _open_outer_paren {
1038 my ($self, $sql) = @_;
1040 while (my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs) {
1042 # there are closing parens inside, need the heavy duty machinery
1043 # to reevaluate the extraction starting from $sql (full reevaluation)
1044 if ($inner =~ /\)/) {
1045 require Text::Balanced;
1047 my (undef, $remainder) = do {
1048 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1050 Text::Balanced::extract_bracketed($sql, '()', qr/\s*/);
1053 # the entire expression needs to be a balanced bracketed thing
1054 # (after an extract no remainder sans trailing space)
1055 last if defined $remainder and $remainder =~ /\S/;
1065 #======================================================================
1067 #======================================================================
1070 my ($self, $arg) = @_;
1072 return '' unless defined($arg) and not (ref($arg) eq 'ARRAY' and !@$arg);
1074 my $expander = sub {
1075 my ($self, $dir, $expr) = @_;
1076 my @exp = map +(defined($dir) ? { -op => [ $dir => $_ ] } : $_),
1077 map $self->_expand_expr($_, undef, -ident),
1078 ref($expr) eq 'ARRAY' ? @$expr : $expr;
1079 return (@exp > 1 ? { -op => [ ',', @exp ] } : $exp[0]);
1082 local $self->{custom_expansions} = {
1083 asc => sub { shift->$expander(asc => @_) },
1084 desc => sub { shift->$expander(desc => @_) },
1087 my $expanded = $self->$expander(undef, $arg);
1089 my ($sql, @bind) = $self->_render_expr($expanded);
1091 my $final_sql = $self->_sqlcase(' order by ').$sql;
1093 return wantarray ? ($final_sql, @bind) : $final_sql;
1096 #======================================================================
1097 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1098 #======================================================================
1103 ($self->_render_expr(
1104 ref($from) eq 'ARRAY'
1106 ',', map $self->_expand_expr($_, undef, -ident), @$from
1108 : $self->_expand_expr($from, undef, -ident)
1113 #======================================================================
1115 #======================================================================
1117 # highly optimized, as it's called way too often
1119 # my ($self, $label) = @_;
1121 return '' unless defined $_[1];
1122 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1124 $_[0]->{quote_char} or
1125 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1127 my $qref = ref $_[0]->{quote_char};
1129 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1130 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1131 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1133 my $esc = $_[0]->{escape_char} || $r;
1135 # parts containing * are naturally unquoted
1136 return join($_[0]->{name_sep}||'', map
1137 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1138 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1143 # Conversion, if applicable
1145 #my ($self, $arg) = @_;
1146 if ($_[0]->{convert_where}) {
1147 return $_[0]->_sqlcase($_[0]->{convert_where}) .'(' . $_[1] . ')';
1154 #my ($self, $col, @vals) = @_;
1155 # called often - tighten code
1156 return $_[0]->{bindtype} eq 'columns'
1157 ? map {[$_[1], $_]} @_[2 .. $#_]
1162 # Dies if any element of @bind is not in [colname => value] format
1163 # if bindtype is 'columns'.
1164 sub _assert_bindval_matches_bindtype {
1165 # my ($self, @bind) = @_;
1167 if ($self->{bindtype} eq 'columns') {
1169 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1170 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1176 sub _join_sql_clauses {
1177 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1179 if (@$clauses_aref > 1) {
1180 my $join = " " . $self->_sqlcase($logic) . " ";
1181 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1182 return ($sql, @$bind_aref);
1184 elsif (@$clauses_aref) {
1185 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1188 return (); # if no SQL, ignore @$bind_aref
1193 # Fix SQL case, if so requested
1195 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1196 # don't touch the argument ... crooked logic, but let's not change it!
1197 return $_[0]->{case} ? $_[1] : uc($_[1]);
1201 #======================================================================
1202 # DISPATCHING FROM REFKIND
1203 #======================================================================
1206 my ($self, $data) = @_;
1208 return 'UNDEF' unless defined $data;
1210 # blessed objects are treated like scalars
1211 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1213 return 'SCALAR' unless $ref;
1216 while ($ref eq 'REF') {
1218 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1222 return ($ref||'SCALAR') . ('REF' x $n_steps);
1226 my ($self, $data) = @_;
1227 my @try = ($self->_refkind($data));
1228 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1229 push @try, 'FALLBACK';
1233 sub _METHOD_FOR_refkind {
1234 my ($self, $meth_prefix, $data) = @_;
1237 for (@{$self->_try_refkind($data)}) {
1238 $method = $self->can($meth_prefix."_".$_)
1242 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1246 sub _SWITCH_refkind {
1247 my ($self, $data, $dispatch_table) = @_;
1250 for (@{$self->_try_refkind($data)}) {
1251 $coderef = $dispatch_table->{$_}
1255 puke "no dispatch entry for ".$self->_refkind($data)
1264 #======================================================================
1265 # VALUES, GENERATE, AUTOLOAD
1266 #======================================================================
1268 # LDNOTE: original code from nwiger, didn't touch code in that section
1269 # I feel the AUTOLOAD stuff should not be the default, it should
1270 # only be activated on explicit demand by user.
1274 my $data = shift || return;
1275 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1276 unless ref $data eq 'HASH';
1279 foreach my $k (sort keys %$data) {
1280 my $v = $data->{$k};
1281 $self->_SWITCH_refkind($v, {
1283 if ($self->{array_datatypes}) { # array datatype
1284 push @all_bind, $self->_bindtype($k, $v);
1286 else { # literal SQL with bind
1287 my ($sql, @bind) = @$v;
1288 $self->_assert_bindval_matches_bindtype(@bind);
1289 push @all_bind, @bind;
1292 ARRAYREFREF => sub { # literal SQL with bind
1293 my ($sql, @bind) = @${$v};
1294 $self->_assert_bindval_matches_bindtype(@bind);
1295 push @all_bind, @bind;
1297 SCALARREF => sub { # literal SQL without bind
1299 SCALAR_or_UNDEF => sub {
1300 push @all_bind, $self->_bindtype($k, $v);
1311 my(@sql, @sqlq, @sqlv);
1315 if ($ref eq 'HASH') {
1316 for my $k (sort keys %$_) {
1319 my $label = $self->_quote($k);
1320 if ($r eq 'ARRAY') {
1321 # literal SQL with bind
1322 my ($sql, @bind) = @$v;
1323 $self->_assert_bindval_matches_bindtype(@bind);
1324 push @sqlq, "$label = $sql";
1326 } elsif ($r eq 'SCALAR') {
1327 # literal SQL without bind
1328 push @sqlq, "$label = $$v";
1330 push @sqlq, "$label = ?";
1331 push @sqlv, $self->_bindtype($k, $v);
1334 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1335 } elsif ($ref eq 'ARRAY') {
1336 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1339 if ($r eq 'ARRAY') { # literal SQL with bind
1340 my ($sql, @bind) = @$v;
1341 $self->_assert_bindval_matches_bindtype(@bind);
1344 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1345 # embedded literal SQL
1352 push @sql, '(' . join(', ', @sqlq) . ')';
1353 } elsif ($ref eq 'SCALAR') {
1357 # strings get case twiddled
1358 push @sql, $self->_sqlcase($_);
1362 my $sql = join ' ', @sql;
1364 # this is pretty tricky
1365 # if ask for an array, return ($stmt, @bind)
1366 # otherwise, s/?/shift @sqlv/ to put it inline
1368 return ($sql, @sqlv);
1370 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1371 ref $d ? $d->[1] : $d/e;
1380 # This allows us to check for a local, then _form, attr
1382 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1383 return $self->generate($name, @_);
1394 SQL::Abstract - Generate SQL from Perl data structures
1400 my $sql = SQL::Abstract->new;
1402 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1404 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1406 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1408 my($stmt, @bind) = $sql->delete($table, \%where);
1410 # Then, use these in your DBI statements
1411 my $sth = $dbh->prepare($stmt);
1412 $sth->execute(@bind);
1414 # Just generate the WHERE clause
1415 my($stmt, @bind) = $sql->where(\%where, $order);
1417 # Return values in the same order, for hashed queries
1418 # See PERFORMANCE section for more details
1419 my @bind = $sql->values(\%fieldvals);
1423 This module was inspired by the excellent L<DBIx::Abstract>.
1424 However, in using that module I found that what I really wanted
1425 to do was generate SQL, but still retain complete control over my
1426 statement handles and use the DBI interface. So, I set out to
1427 create an abstract SQL generation module.
1429 While based on the concepts used by L<DBIx::Abstract>, there are
1430 several important differences, especially when it comes to WHERE
1431 clauses. I have modified the concepts used to make the SQL easier
1432 to generate from Perl data structures and, IMO, more intuitive.
1433 The underlying idea is for this module to do what you mean, based
1434 on the data structures you provide it. The big advantage is that
1435 you don't have to modify your code every time your data changes,
1436 as this module figures it out.
1438 To begin with, an SQL INSERT is as easy as just specifying a hash
1439 of C<key=value> pairs:
1442 name => 'Jimbo Bobson',
1443 phone => '123-456-7890',
1444 address => '42 Sister Lane',
1445 city => 'St. Louis',
1446 state => 'Louisiana',
1449 The SQL can then be generated with this:
1451 my($stmt, @bind) = $sql->insert('people', \%data);
1453 Which would give you something like this:
1455 $stmt = "INSERT INTO people
1456 (address, city, name, phone, state)
1457 VALUES (?, ?, ?, ?, ?)";
1458 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1459 '123-456-7890', 'Louisiana');
1461 These are then used directly in your DBI code:
1463 my $sth = $dbh->prepare($stmt);
1464 $sth->execute(@bind);
1466 =head2 Inserting and Updating Arrays
1468 If your database has array types (like for example Postgres),
1469 activate the special option C<< array_datatypes => 1 >>
1470 when creating the C<SQL::Abstract> object.
1471 Then you may use an arrayref to insert and update database array types:
1473 my $sql = SQL::Abstract->new(array_datatypes => 1);
1475 planets => [qw/Mercury Venus Earth Mars/]
1478 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1482 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1484 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1487 =head2 Inserting and Updating SQL
1489 In order to apply SQL functions to elements of your C<%data> you may
1490 specify a reference to an arrayref for the given hash value. For example,
1491 if you need to execute the Oracle C<to_date> function on a value, you can
1492 say something like this:
1496 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1499 The first value in the array is the actual SQL. Any other values are
1500 optional and would be included in the bind values array. This gives
1503 my($stmt, @bind) = $sql->insert('people', \%data);
1505 $stmt = "INSERT INTO people (name, date_entered)
1506 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1507 @bind = ('Bill', '03/02/2003');
1509 An UPDATE is just as easy, all you change is the name of the function:
1511 my($stmt, @bind) = $sql->update('people', \%data);
1513 Notice that your C<%data> isn't touched; the module will generate
1514 the appropriately quirky SQL for you automatically. Usually you'll
1515 want to specify a WHERE clause for your UPDATE, though, which is
1516 where handling C<%where> hashes comes in handy...
1518 =head2 Complex where statements
1520 This module can generate pretty complicated WHERE statements
1521 easily. For example, simple C<key=value> pairs are taken to mean
1522 equality, and if you want to see if a field is within a set
1523 of values, you can use an arrayref. Let's say we wanted to
1524 SELECT some data based on this criteria:
1527 requestor => 'inna',
1528 worker => ['nwiger', 'rcwe', 'sfz'],
1529 status => { '!=', 'completed' }
1532 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1534 The above would give you something like this:
1536 $stmt = "SELECT * FROM tickets WHERE
1537 ( requestor = ? ) AND ( status != ? )
1538 AND ( worker = ? OR worker = ? OR worker = ? )";
1539 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1541 Which you could then use in DBI code like so:
1543 my $sth = $dbh->prepare($stmt);
1544 $sth->execute(@bind);
1550 The methods are simple. There's one for every major SQL operation,
1551 and a constructor you use first. The arguments are specified in a
1552 similar order for each method (table, then fields, then a where
1553 clause) to try and simplify things.
1555 =head2 new(option => 'value')
1557 The C<new()> function takes a list of options and values, and returns
1558 a new B<SQL::Abstract> object which can then be used to generate SQL
1559 through the methods below. The options accepted are:
1565 If set to 'lower', then SQL will be generated in all lowercase. By
1566 default SQL is generated in "textbook" case meaning something like:
1568 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1570 Any setting other than 'lower' is ignored.
1574 This determines what the default comparison operator is. By default
1575 it is C<=>, meaning that a hash like this:
1577 %where = (name => 'nwiger', email => 'nate@wiger.org');
1579 Will generate SQL like this:
1581 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1583 However, you may want loose comparisons by default, so if you set
1584 C<cmp> to C<like> you would get SQL such as:
1586 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1588 You can also override the comparison on an individual basis - see
1589 the huge section on L</"WHERE CLAUSES"> at the bottom.
1591 =item sqltrue, sqlfalse
1593 Expressions for inserting boolean values within SQL statements.
1594 By default these are C<1=1> and C<1=0>. They are used
1595 by the special operators C<-in> and C<-not_in> for generating
1596 correct SQL even when the argument is an empty array (see below).
1600 This determines the default logical operator for multiple WHERE
1601 statements in arrays or hashes. If absent, the default logic is "or"
1602 for arrays, and "and" for hashes. This means that a WHERE
1606 event_date => {'>=', '2/13/99'},
1607 event_date => {'<=', '4/24/03'},
1610 will generate SQL like this:
1612 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1614 This is probably not what you want given this query, though (look
1615 at the dates). To change the "OR" to an "AND", simply specify:
1617 my $sql = SQL::Abstract->new(logic => 'and');
1619 Which will change the above C<WHERE> to:
1621 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1623 The logic can also be changed locally by inserting
1624 a modifier in front of an arrayref:
1626 @where = (-and => [event_date => {'>=', '2/13/99'},
1627 event_date => {'<=', '4/24/03'} ]);
1629 See the L</"WHERE CLAUSES"> section for explanations.
1633 This will automatically convert comparisons using the specified SQL
1634 function for both column and value. This is mostly used with an argument
1635 of C<upper> or C<lower>, so that the SQL will have the effect of
1636 case-insensitive "searches". For example, this:
1638 $sql = SQL::Abstract->new(convert => 'upper');
1639 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1641 Will turn out the following SQL:
1643 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1645 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1646 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1647 not validate this option; it will just pass through what you specify verbatim).
1651 This is a kludge because many databases suck. For example, you can't
1652 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1653 Instead, you have to use C<bind_param()>:
1655 $sth->bind_param(1, 'reg data');
1656 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1658 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1659 which loses track of which field each slot refers to. Fear not.
1661 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1662 Currently, you can specify either C<normal> (default) or C<columns>. If you
1663 specify C<columns>, you will get an array that looks like this:
1665 my $sql = SQL::Abstract->new(bindtype => 'columns');
1666 my($stmt, @bind) = $sql->insert(...);
1669 [ 'column1', 'value1' ],
1670 [ 'column2', 'value2' ],
1671 [ 'column3', 'value3' ],
1674 You can then iterate through this manually, using DBI's C<bind_param()>.
1676 $sth->prepare($stmt);
1679 my($col, $data) = @$_;
1680 if ($col eq 'details' || $col eq 'comments') {
1681 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1682 } elsif ($col eq 'image') {
1683 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1685 $sth->bind_param($i, $data);
1689 $sth->execute; # execute without @bind now
1691 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1692 Basically, the advantage is still that you don't have to care which fields
1693 are or are not included. You could wrap that above C<for> loop in a simple
1694 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1695 get a layer of abstraction over manual SQL specification.
1697 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1698 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1699 will expect the bind values in this format.
1703 This is the character that a table or column name will be quoted
1704 with. By default this is an empty string, but you could set it to
1705 the character C<`>, to generate SQL like this:
1707 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1709 Alternatively, you can supply an array ref of two items, the first being the left
1710 hand quote character, and the second the right hand quote character. For
1711 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1712 that generates SQL like this:
1714 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1716 Quoting is useful if you have tables or columns names that are reserved
1717 words in your database's SQL dialect.
1721 This is the character that will be used to escape L</quote_char>s appearing
1722 in an identifier before it has been quoted.
1724 The parameter default in case of a single L</quote_char> character is the quote
1727 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1728 this parameter defaults to the B<closing (right)> L</quote_char>. Occurrences
1729 of the B<opening (left)> L</quote_char> within the identifier are currently left
1730 untouched. The default for opening-closing-style quotes may change in future
1731 versions, thus you are B<strongly encouraged> to specify the escape character
1736 This is the character that separates a table and column name. It is
1737 necessary to specify this when the C<quote_char> option is selected,
1738 so that tables and column names can be individually quoted like this:
1740 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1742 =item injection_guard
1744 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1745 column name specified in a query structure. This is a safety mechanism to avoid
1746 injection attacks when mishandling user input e.g.:
1748 my %condition_as_column_value_pairs = get_values_from_user();
1749 $sqla->select( ... , \%condition_as_column_value_pairs );
1751 If the expression matches an exception is thrown. Note that literal SQL
1752 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1754 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1756 =item array_datatypes
1758 When this option is true, arrayrefs in INSERT or UPDATE are
1759 interpreted as array datatypes and are passed directly
1761 When this option is false, arrayrefs are interpreted
1762 as literal SQL, just like refs to arrayrefs
1763 (but this behavior is for backwards compatibility; when writing
1764 new queries, use the "reference to arrayref" syntax
1770 Takes a reference to a list of "special operators"
1771 to extend the syntax understood by L<SQL::Abstract>.
1772 See section L</"SPECIAL OPERATORS"> for details.
1776 Takes a reference to a list of "unary operators"
1777 to extend the syntax understood by L<SQL::Abstract>.
1778 See section L</"UNARY OPERATORS"> for details.
1784 =head2 insert($table, \@values || \%fieldvals, \%options)
1786 This is the simplest function. You simply give it a table name
1787 and either an arrayref of values or hashref of field/value pairs.
1788 It returns an SQL INSERT statement and a list of bind values.
1789 See the sections on L</"Inserting and Updating Arrays"> and
1790 L</"Inserting and Updating SQL"> for information on how to insert
1791 with those data types.
1793 The optional C<\%options> hash reference may contain additional
1794 options to generate the insert SQL. Currently supported options
1801 Takes either a scalar of raw SQL fields, or an array reference of
1802 field names, and adds on an SQL C<RETURNING> statement at the end.
1803 This allows you to return data generated by the insert statement
1804 (such as row IDs) without performing another C<SELECT> statement.
1805 Note, however, this is not part of the SQL standard and may not
1806 be supported by all database engines.
1810 =head2 update($table, \%fieldvals, \%where, \%options)
1812 This takes a table, hashref of field/value pairs, and an optional
1813 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1815 See the sections on L</"Inserting and Updating Arrays"> and
1816 L</"Inserting and Updating SQL"> for information on how to insert
1817 with those data types.
1819 The optional C<\%options> hash reference may contain additional
1820 options to generate the update SQL. Currently supported options
1827 See the C<returning> option to
1828 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1832 =head2 select($source, $fields, $where, $order)
1834 This returns a SQL SELECT statement and associated list of bind values, as
1835 specified by the arguments:
1841 Specification of the 'FROM' part of the statement.
1842 The argument can be either a plain scalar (interpreted as a table
1843 name, will be quoted), or an arrayref (interpreted as a list
1844 of table names, joined by commas, quoted), or a scalarref
1845 (literal SQL, not quoted).
1849 Specification of the list of fields to retrieve from
1851 The argument can be either an arrayref (interpreted as a list
1852 of field names, will be joined by commas and quoted), or a
1853 plain scalar (literal SQL, not quoted).
1854 Please observe that this API is not as flexible as that of
1855 the first argument C<$source>, for backwards compatibility reasons.
1859 Optional argument to specify the WHERE part of the query.
1860 The argument is most often a hashref, but can also be
1861 an arrayref or plain scalar --
1862 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1866 Optional argument to specify the ORDER BY part of the query.
1867 The argument can be a scalar, a hashref or an arrayref
1868 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1874 =head2 delete($table, \%where, \%options)
1876 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1877 It returns an SQL DELETE statement and list of bind values.
1879 The optional C<\%options> hash reference may contain additional
1880 options to generate the delete SQL. Currently supported options
1887 See the C<returning> option to
1888 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
1892 =head2 where(\%where, $order)
1894 This is used to generate just the WHERE clause. For example,
1895 if you have an arbitrary data structure and know what the
1896 rest of your SQL is going to look like, but want an easy way
1897 to produce a WHERE clause, use this. It returns an SQL WHERE
1898 clause and list of bind values.
1901 =head2 values(\%data)
1903 This just returns the values from the hash C<%data>, in the same
1904 order that would be returned from any of the other above queries.
1905 Using this allows you to markedly speed up your queries if you
1906 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
1908 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
1910 Warning: This is an experimental method and subject to change.
1912 This returns arbitrarily generated SQL. It's a really basic shortcut.
1913 It will return two different things, depending on return context:
1915 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
1916 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
1918 These would return the following:
1920 # First calling form
1921 $stmt = "CREATE TABLE test (?, ?)";
1922 @bind = (field1, field2);
1924 # Second calling form
1925 $stmt_and_val = "CREATE TABLE test (field1, field2)";
1927 Depending on what you're trying to do, it's up to you to choose the correct
1928 format. In this example, the second form is what you would want.
1932 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
1936 ALTER SESSION SET nls_date_format = 'MM/YY'
1938 You get the idea. Strings get their case twiddled, but everything
1939 else remains verbatim.
1941 =head1 EXPORTABLE FUNCTIONS
1943 =head2 is_plain_value
1945 Determines if the supplied argument is a plain value as understood by this
1950 =item * The value is C<undef>
1952 =item * The value is a non-reference
1954 =item * The value is an object with stringification overloading
1956 =item * The value is of the form C<< { -value => $anything } >>
1960 On failure returns C<undef>, on success returns a B<scalar> reference
1961 to the original supplied argument.
1967 The stringification overloading detection is rather advanced: it takes
1968 into consideration not only the presence of a C<""> overload, but if that
1969 fails also checks for enabled
1970 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
1971 on either C<0+> or C<bool>.
1973 Unfortunately testing in the field indicates that this
1974 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
1975 but only when very large numbers of stringifying objects are involved.
1976 At the time of writing ( Sep 2014 ) there is no clear explanation of
1977 the direct cause, nor is there a manageably small test case that reliably
1978 reproduces the problem.
1980 If you encounter any of the following exceptions in B<random places within
1981 your application stack> - this module may be to blame:
1983 Operation "ne": no method found,
1984 left argument in overloaded package <something>,
1985 right argument in overloaded package <something>
1989 Stub found while resolving method "???" overloading """" in package <something>
1991 If you fall victim to the above - please attempt to reduce the problem
1992 to something that could be sent to the L<SQL::Abstract developers
1993 |DBIx::Class/GETTING HELP/SUPPORT>
1994 (either publicly or privately). As a workaround in the meantime you can
1995 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
1996 value, which will most likely eliminate your problem (at the expense of
1997 not being able to properly detect exotic forms of stringification).
1999 This notice and environment variable will be removed in a future version,
2000 as soon as the underlying problem is found and a reliable workaround is
2005 =head2 is_literal_value
2007 Determines if the supplied argument is a literal value as understood by this
2012 =item * C<\$sql_string>
2014 =item * C<\[ $sql_string, @bind_values ]>
2018 On failure returns C<undef>, on success returns an B<array> reference
2019 containing the unpacked version of the supplied literal SQL and bind values.
2021 =head1 WHERE CLAUSES
2025 This module uses a variation on the idea from L<DBIx::Abstract>. It
2026 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2027 module is that things in arrays are OR'ed, and things in hashes
2030 The easiest way to explain is to show lots of examples. After
2031 each C<%where> hash shown, it is assumed you used:
2033 my($stmt, @bind) = $sql->where(\%where);
2035 However, note that the C<%where> hash can be used directly in any
2036 of the other functions as well, as described above.
2038 =head2 Key-value pairs
2040 So, let's get started. To begin, a simple hash:
2044 status => 'completed'
2047 Is converted to SQL C<key = val> statements:
2049 $stmt = "WHERE user = ? AND status = ?";
2050 @bind = ('nwiger', 'completed');
2052 One common thing I end up doing is having a list of values that
2053 a field can be in. To do this, simply specify a list inside of
2058 status => ['assigned', 'in-progress', 'pending'];
2061 This simple code will create the following:
2063 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2064 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2066 A field associated to an empty arrayref will be considered a
2067 logical false and will generate 0=1.
2069 =head2 Tests for NULL values
2071 If the value part is C<undef> then this is converted to SQL <IS NULL>
2080 $stmt = "WHERE user = ? AND status IS NULL";
2083 To test if a column IS NOT NULL:
2087 status => { '!=', undef },
2090 =head2 Specific comparison operators
2092 If you want to specify a different type of operator for your comparison,
2093 you can use a hashref for a given column:
2097 status => { '!=', 'completed' }
2100 Which would generate:
2102 $stmt = "WHERE user = ? AND status != ?";
2103 @bind = ('nwiger', 'completed');
2105 To test against multiple values, just enclose the values in an arrayref:
2107 status => { '=', ['assigned', 'in-progress', 'pending'] };
2109 Which would give you:
2111 "WHERE status = ? OR status = ? OR status = ?"
2114 The hashref can also contain multiple pairs, in which case it is expanded
2115 into an C<AND> of its elements:
2119 status => { '!=', 'completed', -not_like => 'pending%' }
2122 # Or more dynamically, like from a form
2123 $where{user} = 'nwiger';
2124 $where{status}{'!='} = 'completed';
2125 $where{status}{'-not_like'} = 'pending%';
2127 # Both generate this
2128 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2129 @bind = ('nwiger', 'completed', 'pending%');
2132 To get an OR instead, you can combine it with the arrayref idea:
2136 priority => [ { '=', 2 }, { '>', 5 } ]
2139 Which would generate:
2141 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2142 @bind = ('2', '5', 'nwiger');
2144 If you want to include literal SQL (with or without bind values), just use a
2145 scalar reference or reference to an arrayref as the value:
2148 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2149 date_expires => { '<' => \"now()" }
2152 Which would generate:
2154 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2155 @bind = ('11/26/2008');
2158 =head2 Logic and nesting operators
2160 In the example above,
2161 there is a subtle trap if you want to say something like
2162 this (notice the C<AND>):
2164 WHERE priority != ? AND priority != ?
2166 Because, in Perl you I<can't> do this:
2168 priority => { '!=' => 2, '!=' => 1 }
2170 As the second C<!=> key will obliterate the first. The solution
2171 is to use the special C<-modifier> form inside an arrayref:
2173 priority => [ -and => {'!=', 2},
2177 Normally, these would be joined by C<OR>, but the modifier tells it
2178 to use C<AND> instead. (Hint: You can use this in conjunction with the
2179 C<logic> option to C<new()> in order to change the way your queries
2180 work by default.) B<Important:> Note that the C<-modifier> goes
2181 B<INSIDE> the arrayref, as an extra first element. This will
2182 B<NOT> do what you think it might:
2184 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2186 Here is a quick list of equivalencies, since there is some overlap:
2189 status => {'!=', 'completed', 'not like', 'pending%' }
2190 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2193 status => {'=', ['assigned', 'in-progress']}
2194 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2195 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2199 =head2 Special operators: IN, BETWEEN, etc.
2201 You can also use the hashref format to compare a list of fields using the
2202 C<IN> comparison operator, by specifying the list as an arrayref:
2205 status => 'completed',
2206 reportid => { -in => [567, 2335, 2] }
2209 Which would generate:
2211 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2212 @bind = ('completed', '567', '2335', '2');
2214 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2217 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2218 (by default: C<1=0>). Similarly, C<< -not_in => [] >> generates
2219 'sqltrue' (by default: C<1=1>).
2221 In addition to the array you can supply a chunk of literal sql or
2222 literal sql with bind:
2225 customer => { -in => \[
2226 'SELECT cust_id FROM cust WHERE balance > ?',
2229 status => { -in => \'SELECT status_codes FROM states' },
2235 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2236 AND status IN ( SELECT status_codes FROM states )
2240 Finally, if the argument to C<-in> is not a reference, it will be
2241 treated as a single-element array.
2243 Another pair of operators is C<-between> and C<-not_between>,
2244 used with an arrayref of two values:
2248 completion_date => {
2249 -not_between => ['2002-10-01', '2003-02-06']
2255 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2257 Just like with C<-in> all plausible combinations of literal SQL
2261 start0 => { -between => [ 1, 2 ] },
2262 start1 => { -between => \["? AND ?", 1, 2] },
2263 start2 => { -between => \"lower(x) AND upper(y)" },
2264 start3 => { -between => [
2266 \["upper(?)", 'stuff' ],
2273 ( start0 BETWEEN ? AND ? )
2274 AND ( start1 BETWEEN ? AND ? )
2275 AND ( start2 BETWEEN lower(x) AND upper(y) )
2276 AND ( start3 BETWEEN lower(x) AND upper(?) )
2278 @bind = (1, 2, 1, 2, 'stuff');
2281 These are the two builtin "special operators"; but the
2282 list can be expanded: see section L</"SPECIAL OPERATORS"> below.
2284 =head2 Unary operators: bool
2286 If you wish to test against boolean columns or functions within your
2287 database you can use the C<-bool> and C<-not_bool> operators. For
2288 example to test the column C<is_user> being true and the column
2289 C<is_enabled> being false you would use:-
2293 -not_bool => 'is_enabled',
2298 WHERE is_user AND NOT is_enabled
2300 If a more complex combination is required, testing more conditions,
2301 then you should use the and/or operators:-
2306 -not_bool => { two=> { -rlike => 'bar' } },
2307 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2318 (NOT ( three = ? OR three > ? ))
2321 =head2 Nested conditions, -and/-or prefixes
2323 So far, we've seen how multiple conditions are joined with a top-level
2324 C<AND>. We can change this by putting the different conditions we want in
2325 hashes and then putting those hashes in an array. For example:
2330 status => { -like => ['pending%', 'dispatched'] },
2334 status => 'unassigned',
2338 This data structure would create the following:
2340 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2341 OR ( user = ? AND status = ? ) )";
2342 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2345 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2346 to change the logic inside:
2352 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2353 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2360 $stmt = "WHERE ( user = ?
2361 AND ( ( workhrs > ? AND geo = ? )
2362 OR ( workhrs < ? OR geo = ? ) ) )";
2363 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2365 =head3 Algebraic inconsistency, for historical reasons
2367 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2368 operator goes C<outside> of the nested structure; whereas when connecting
2369 several constraints on one column, the C<-and> operator goes
2370 C<inside> the arrayref. Here is an example combining both features:
2373 -and => [a => 1, b => 2],
2374 -or => [c => 3, d => 4],
2375 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2380 WHERE ( ( ( a = ? AND b = ? )
2381 OR ( c = ? OR d = ? )
2382 OR ( e LIKE ? AND e LIKE ? ) ) )
2384 This difference in syntax is unfortunate but must be preserved for
2385 historical reasons. So be careful: the two examples below would
2386 seem algebraically equivalent, but they are not
2389 { -like => 'foo%' },
2390 { -like => '%bar' },
2392 # yields: WHERE ( ( col LIKE ? AND col LIKE ? ) )
2395 { col => { -like => 'foo%' } },
2396 { col => { -like => '%bar' } },
2398 # yields: WHERE ( ( col LIKE ? OR col LIKE ? ) )
2401 =head2 Literal SQL and value type operators
2403 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2404 side" is a column name and the "right side" is a value (normally rendered as
2405 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2406 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2407 alter this behavior. There are several ways of doing so.
2411 This is a virtual operator that signals the string to its right side is an
2412 identifier (a column name) and not a value. For example to compare two
2413 columns you would write:
2416 priority => { '<', 2 },
2417 requestor => { -ident => 'submitter' },
2422 $stmt = "WHERE priority < ? AND requestor = submitter";
2425 If you are maintaining legacy code you may see a different construct as
2426 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2431 This is a virtual operator that signals that the construct to its right side
2432 is a value to be passed to DBI. This is for example necessary when you want
2433 to write a where clause against an array (for RDBMS that support such
2434 datatypes). For example:
2437 array => { -value => [1, 2, 3] }
2442 $stmt = 'WHERE array = ?';
2443 @bind = ([1, 2, 3]);
2445 Note that if you were to simply say:
2451 the result would probably not be what you wanted:
2453 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2458 Finally, sometimes only literal SQL will do. To include a random snippet
2459 of SQL verbatim, you specify it as a scalar reference. Consider this only
2460 as a last resort. Usually there is a better way. For example:
2463 priority => { '<', 2 },
2464 requestor => { -in => \'(SELECT name FROM hitmen)' },
2469 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2472 Note that in this example, you only get one bind parameter back, since
2473 the verbatim SQL is passed as part of the statement.
2477 Never use untrusted input as a literal SQL argument - this is a massive
2478 security risk (there is no way to check literal snippets for SQL
2479 injections and other nastyness). If you need to deal with untrusted input
2480 use literal SQL with placeholders as described next.
2482 =head3 Literal SQL with placeholders and bind values (subqueries)
2484 If the literal SQL to be inserted has placeholders and bind values,
2485 use a reference to an arrayref (yes this is a double reference --
2486 not so common, but perfectly legal Perl). For example, to find a date
2487 in Postgres you can use something like this:
2490 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2495 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2498 Note that you must pass the bind values in the same format as they are returned
2499 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2500 to C<columns>, you must provide the bind values in the
2501 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2502 scalar value; most commonly the column name, but you can use any scalar value
2503 (including references and blessed references), L<SQL::Abstract> will simply
2504 pass it through intact. So if C<bindtype> is set to C<columns> the above
2505 example will look like:
2508 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2511 Literal SQL is especially useful for nesting parenthesized clauses in the
2512 main SQL query. Here is a first example:
2514 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2518 bar => \["IN ($sub_stmt)" => @sub_bind],
2523 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2524 WHERE c2 < ? AND c3 LIKE ?))";
2525 @bind = (1234, 100, "foo%");
2527 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2528 are expressed in the same way. Of course the C<$sub_stmt> and
2529 its associated bind values can be generated through a former call
2532 my ($sub_stmt, @sub_bind)
2533 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2534 c3 => {-like => "foo%"}});
2537 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2540 In the examples above, the subquery was used as an operator on a column;
2541 but the same principle also applies for a clause within the main C<%where>
2542 hash, like an EXISTS subquery:
2544 my ($sub_stmt, @sub_bind)
2545 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2546 my %where = ( -and => [
2548 \["EXISTS ($sub_stmt)" => @sub_bind],
2553 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2554 WHERE c1 = ? AND c2 > t0.c0))";
2558 Observe that the condition on C<c2> in the subquery refers to
2559 column C<t0.c0> of the main query: this is I<not> a bind
2560 value, so we have to express it through a scalar ref.
2561 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2562 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2563 what we wanted here.
2565 Finally, here is an example where a subquery is used
2566 for expressing unary negation:
2568 my ($sub_stmt, @sub_bind)
2569 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2570 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2572 lname => {like => '%son%'},
2573 \["NOT ($sub_stmt)" => @sub_bind],
2578 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2579 @bind = ('%son%', 10, 20)
2581 =head3 Deprecated usage of Literal SQL
2583 Below are some examples of archaic use of literal SQL. It is shown only as
2584 reference for those who deal with legacy code. Each example has a much
2585 better, cleaner and safer alternative that users should opt for in new code.
2591 my %where = ( requestor => \'IS NOT NULL' )
2593 $stmt = "WHERE requestor IS NOT NULL"
2595 This used to be the way of generating NULL comparisons, before the handling
2596 of C<undef> got formalized. For new code please use the superior syntax as
2597 described in L</Tests for NULL values>.
2601 my %where = ( requestor => \'= submitter' )
2603 $stmt = "WHERE requestor = submitter"
2605 This used to be the only way to compare columns. Use the superior L</-ident>
2606 method for all new code. For example an identifier declared in such a way
2607 will be properly quoted if L</quote_char> is properly set, while the legacy
2608 form will remain as supplied.
2612 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2614 $stmt = "WHERE completed > ? AND is_ready"
2615 @bind = ('2012-12-21')
2617 Using an empty string literal used to be the only way to express a boolean.
2618 For all new code please use the much more readable
2619 L<-bool|/Unary operators: bool> operator.
2625 These pages could go on for a while, since the nesting of the data
2626 structures this module can handle are pretty much unlimited (the
2627 module implements the C<WHERE> expansion as a recursive function
2628 internally). Your best bet is to "play around" with the module a
2629 little to see how the data structures behave, and choose the best
2630 format for your data based on that.
2632 And of course, all the values above will probably be replaced with
2633 variables gotten from forms or the command line. After all, if you
2634 knew everything ahead of time, you wouldn't have to worry about
2635 dynamically-generating SQL and could just hardwire it into your
2638 =head1 ORDER BY CLAUSES
2640 Some functions take an order by clause. This can either be a scalar (just a
2641 column name), a hashref of C<< { -desc => 'col' } >> or C<< { -asc => 'col' }
2642 >>, a scalarref, an arrayref-ref, or an arrayref of any of the previous
2645 Given | Will Generate
2646 ---------------------------------------------------------------
2648 'colA' | ORDER BY colA
2650 [qw/colA colB/] | ORDER BY colA, colB
2652 {-asc => 'colA'} | ORDER BY colA ASC
2654 {-desc => 'colB'} | ORDER BY colB DESC
2656 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2658 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2660 \'colA DESC' | ORDER BY colA DESC
2662 \[ 'FUNC(colA, ?)', $x ] | ORDER BY FUNC(colA, ?)
2663 | /* ...with $x bound to ? */
2666 { -asc => 'colA' }, | colA ASC,
2667 { -desc => [qw/colB/] }, | colB DESC,
2668 { -asc => [qw/colC colD/] },| colC ASC, colD ASC,
2669 \'colE DESC', | colE DESC,
2670 \[ 'FUNC(colF, ?)', $x ], | FUNC(colF, ?)
2671 ] | /* ...with $x bound to ? */
2672 ===============================================================
2676 =head1 SPECIAL OPERATORS
2678 my $sqlmaker = SQL::Abstract->new(special_ops => [
2682 my ($self, $field, $op, $arg) = @_;
2688 handler => 'method_name',
2692 A "special operator" is a SQL syntactic clause that can be
2693 applied to a field, instead of a usual binary operator.
2696 WHERE field IN (?, ?, ?)
2697 WHERE field BETWEEN ? AND ?
2698 WHERE MATCH(field) AGAINST (?, ?)
2700 Special operators IN and BETWEEN are fairly standard and therefore
2701 are builtin within C<SQL::Abstract> (as the overridable methods
2702 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2703 like the MATCH .. AGAINST example above which is specific to MySQL,
2704 you can write your own operator handlers - supply a C<special_ops>
2705 argument to the C<new> method. That argument takes an arrayref of
2706 operator definitions; each operator definition is a hashref with two
2713 the regular expression to match the operator
2717 Either a coderef or a plain scalar method name. In both cases
2718 the expected return is C<< ($sql, @bind) >>.
2720 When supplied with a method name, it is simply called on the
2721 L<SQL::Abstract> object as:
2723 $self->$method_name($field, $op, $arg)
2727 $field is the LHS of the operator
2728 $op is the part that matched the handler regex
2731 When supplied with a coderef, it is called as:
2733 $coderef->($self, $field, $op, $arg)
2738 For example, here is an implementation
2739 of the MATCH .. AGAINST syntax for MySQL
2741 my $sqlmaker = SQL::Abstract->new(special_ops => [
2743 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2744 {regex => qr/^match$/i,
2746 my ($self, $field, $op, $arg) = @_;
2747 $arg = [$arg] if not ref $arg;
2748 my $label = $self->_quote($field);
2749 my ($placeholder) = $self->_convert('?');
2750 my $placeholders = join ", ", (($placeholder) x @$arg);
2751 my $sql = $self->_sqlcase('match') . " ($label) "
2752 . $self->_sqlcase('against') . " ($placeholders) ";
2753 my @bind = $self->_bindtype($field, @$arg);
2754 return ($sql, @bind);
2761 =head1 UNARY OPERATORS
2763 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2767 my ($self, $op, $arg) = @_;
2773 handler => 'method_name',
2777 A "unary operator" is a SQL syntactic clause that can be
2778 applied to a field - the operator goes before the field
2780 You can write your own operator handlers - supply a C<unary_ops>
2781 argument to the C<new> method. That argument takes an arrayref of
2782 operator definitions; each operator definition is a hashref with two
2789 the regular expression to match the operator
2793 Either a coderef or a plain scalar method name. In both cases
2794 the expected return is C<< $sql >>.
2796 When supplied with a method name, it is simply called on the
2797 L<SQL::Abstract> object as:
2799 $self->$method_name($op, $arg)
2803 $op is the part that matched the handler regex
2804 $arg is the RHS or argument of the operator
2806 When supplied with a coderef, it is called as:
2808 $coderef->($self, $op, $arg)
2816 Thanks to some benchmarking by Mark Stosberg, it turns out that
2817 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2818 I must admit this wasn't an intentional design issue, but it's a
2819 byproduct of the fact that you get to control your C<DBI> handles
2822 To maximize performance, use a code snippet like the following:
2824 # prepare a statement handle using the first row
2825 # and then reuse it for the rest of the rows
2827 for my $href (@array_of_hashrefs) {
2828 $stmt ||= $sql->insert('table', $href);
2829 $sth ||= $dbh->prepare($stmt);
2830 $sth->execute($sql->values($href));
2833 The reason this works is because the keys in your C<$href> are sorted
2834 internally by B<SQL::Abstract>. Thus, as long as your data retains
2835 the same structure, you only have to generate the SQL the first time
2836 around. On subsequent queries, simply use the C<values> function provided
2837 by this module to return your values in the correct order.
2839 However this depends on the values having the same type - if, for
2840 example, the values of a where clause may either have values
2841 (resulting in sql of the form C<column = ?> with a single bind
2842 value), or alternatively the values might be C<undef> (resulting in
2843 sql of the form C<column IS NULL> with no bind value) then the
2844 caching technique suggested will not work.
2848 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2849 really like this part (I do, at least). Building up a complex query
2850 can be as simple as the following:
2857 use CGI::FormBuilder;
2860 my $form = CGI::FormBuilder->new(...);
2861 my $sql = SQL::Abstract->new;
2863 if ($form->submitted) {
2864 my $field = $form->field;
2865 my $id = delete $field->{id};
2866 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2869 Of course, you would still have to connect using C<DBI> to run the
2870 query, but the point is that if you make your form look like your
2871 table, the actual query script can be extremely simplistic.
2873 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2874 a fast interface to returning and formatting data. I frequently
2875 use these three modules together to write complex database query
2876 apps in under 50 lines.
2878 =head1 HOW TO CONTRIBUTE
2880 Contributions are always welcome, in all usable forms (we especially
2881 welcome documentation improvements). The delivery methods include git-
2882 or unified-diff formatted patches, GitHub pull requests, or plain bug
2883 reports either via RT or the Mailing list. Contributors are generally
2884 granted full access to the official repository after their first several
2885 patches pass successful review.
2887 This project is maintained in a git repository. The code and related tools are
2888 accessible at the following locations:
2892 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2894 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2896 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
2898 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
2904 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2905 Great care has been taken to preserve the I<published> behavior
2906 documented in previous versions in the 1.* family; however,
2907 some features that were previously undocumented, or behaved
2908 differently from the documentation, had to be changed in order
2909 to clarify the semantics. Hence, client code that was relying
2910 on some dark areas of C<SQL::Abstract> v1.*
2911 B<might behave differently> in v1.50.
2913 The main changes are:
2919 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
2923 support for the { operator => \"..." } construct (to embed literal SQL)
2927 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2931 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2935 defensive programming: check arguments
2939 fixed bug with global logic, which was previously implemented
2940 through global variables yielding side-effects. Prior versions would
2941 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2942 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2943 Now this is interpreted
2944 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2949 fixed semantics of _bindtype on array args
2953 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2954 we just avoid shifting arrays within that tree.
2958 dropped the C<_modlogic> function
2962 =head1 ACKNOWLEDGEMENTS
2964 There are a number of individuals that have really helped out with
2965 this module. Unfortunately, most of them submitted bugs via CPAN
2966 so I have no idea who they are! But the people I do know are:
2968 Ash Berlin (order_by hash term support)
2969 Matt Trout (DBIx::Class support)
2970 Mark Stosberg (benchmarking)
2971 Chas Owens (initial "IN" operator support)
2972 Philip Collins (per-field SQL functions)
2973 Eric Kolve (hashref "AND" support)
2974 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2975 Dan Kubb (support for "quote_char" and "name_sep")
2976 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2977 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2978 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2979 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2980 Oliver Charles (support for "RETURNING" after "INSERT")
2986 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
2990 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
2992 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
2994 For support, your best bet is to try the C<DBIx::Class> users mailing list.
2995 While not an official support venue, C<DBIx::Class> makes heavy use of
2996 C<SQL::Abstract>, and as such list members there are very familiar with
2997 how to create queries.
3001 This module is free software; you may copy this under the same
3002 terms as perl itself (either the GNU General Public License or
3003 the Artistic License)