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 = '1.81';
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 => '_where_field_BETWEEN'},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => '_where_field_IN'},
42 {regex => qr/^ ident $/ix, handler => '_where_op_IDENT'},
43 {regex => qr/^ value $/ix, handler => '_where_op_VALUE'},
44 {regex => qr/^ is (?: \s+ not )? $/ix, handler => '_where_field_IS'},
47 # unaryish operators - key maps to handler
48 my @BUILTIN_UNARY_OPS = (
49 # the digits are backcompat stuff
50 { regex => qr/^ and (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
51 { regex => qr/^ or (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
52 { regex => qr/^ nest (?: [_\s]? \d+ )? $/xi, handler => '_where_op_NEST' },
53 { regex => qr/^ (?: not \s )? bool $/xi, handler => '_where_op_BOOL' },
54 { regex => qr/^ ident $/xi, handler => '_where_op_IDENT' },
55 { regex => qr/^ value $/xi, handler => '_where_op_VALUE' },
58 #======================================================================
59 # DEBUGGING AND ERROR REPORTING
60 #======================================================================
63 return unless $_[0]->{debug}; shift; # a little faster
64 my $func = (caller(1))[3];
65 warn "[$func] ", @_, "\n";
69 my($func) = (caller(1))[3];
70 Carp::carp "[$func] Warning: ", @_;
74 my($func) = (caller(1))[3];
75 Carp::croak "[$func] Fatal: ", @_;
78 sub is_literal_value ($) {
79 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
80 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
84 # FIXME XSify - this can be done so much more efficiently
85 sub is_plain_value ($) {
87 ! length ref $_[0] ? \($_[0])
89 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
91 exists $_[0]->{-value}
92 ) ? \($_[0]->{-value})
94 # reuse @_ for even moar speedz
95 defined ( $_[1] = Scalar::Util::blessed $_[0] )
97 # deliberately not using Devel::OverloadInfo - the checks we are
98 # intersted in are much more limited than the fullblown thing, and
99 # this is a very hot piece of code
101 # simply using ->can('(""') can leave behind stub methods that
102 # break actually using the overload later (see L<perldiag/Stub
103 # found while resolving method "%s" overloading "%s" in package
104 # "%s"> and the source of overload::mycan())
106 # either has stringification which DBI SHOULD prefer out of the box
107 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
109 # has nummification or boolification, AND fallback is *not* disabled
111 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
114 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
116 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
120 # no fallback specified at all
121 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
123 # fallback explicitly undef
124 ! defined ${"$_[3]::()"}
137 #======================================================================
139 #======================================================================
143 my $class = ref($self) || $self;
144 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
146 # choose our case by keeping an option around
147 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
149 # default logic for interpreting arrayrefs
150 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
152 # how to return bind vars
153 $opt{bindtype} ||= 'normal';
155 # default comparison is "=", but can be overridden
158 # try to recognize which are the 'equality' and 'inequality' ops
159 # (temporary quickfix (in 2007), should go through a more seasoned API)
160 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
161 $opt{inequality_op} = qr/^( != | <> )$/ix;
163 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
164 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
167 $opt{sqltrue} ||= '1=1';
168 $opt{sqlfalse} ||= '0=1';
171 $opt{special_ops} ||= [];
172 # regexes are applied in order, thus push after user-defines
173 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
176 $opt{unary_ops} ||= [];
177 push @{$opt{unary_ops}}, @BUILTIN_UNARY_OPS;
179 # rudimentary sanity-check for user supplied bits treated as functions/operators
180 # If a purported function matches this regular expression, an exception is thrown.
181 # Literal SQL is *NOT* subject to this check, only functions (and column names
182 # when quoting is not in effect)
185 # need to guard against ()'s in column names too, but this will break tons of
186 # hacks... ideas anyone?
187 $opt{injection_guard} ||= qr/
193 return bless \%opt, $class;
197 sub _assert_pass_injection_guard {
198 if ($_[1] =~ $_[0]->{injection_guard}) {
199 my $class = ref $_[0];
200 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
201 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
202 . "{injection_guard} attribute to ${class}->new()"
207 #======================================================================
209 #======================================================================
213 my $table = $self->_table(shift);
214 my $data = shift || return;
217 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
218 my ($sql, @bind) = $self->$method($data);
219 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
221 if ($options->{returning}) {
222 my ($s, @b) = $self->_insert_returning ($options);
227 return wantarray ? ($sql, @bind) : $sql;
230 # Used by DBIx::Class::SQLMaker->insert
231 sub _insert_returning { shift->_returning(@_) }
234 my ($self, $options) = @_;
236 my $f = $options->{returning};
238 my $fieldlist = $self->_SWITCH_refkind($f, {
239 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
240 SCALAR => sub {$self->_quote($f)},
241 SCALARREF => sub {$$f},
243 return $self->_sqlcase(' returning ') . $fieldlist;
246 sub _insert_HASHREF { # explicit list of fields and then values
247 my ($self, $data) = @_;
249 my @fields = sort keys %$data;
251 my ($sql, @bind) = $self->_insert_values($data);
254 $_ = $self->_quote($_) foreach @fields;
255 $sql = "( ".join(", ", @fields).") ".$sql;
257 return ($sql, @bind);
260 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
261 my ($self, $data) = @_;
263 # no names (arrayref) so can't generate bindtype
264 $self->{bindtype} ne 'columns'
265 or belch "can't do 'columns' bindtype when called with arrayref";
267 # fold the list of values into a hash of column name - value pairs
268 # (where the column names are artificially generated, and their
269 # lexicographical ordering keep the ordering of the original list)
270 my $i = "a"; # incremented values will be in lexicographical order
271 my $data_in_hash = { map { ($i++ => $_) } @$data };
273 return $self->_insert_values($data_in_hash);
276 sub _insert_ARRAYREFREF { # literal SQL with bind
277 my ($self, $data) = @_;
279 my ($sql, @bind) = @${$data};
280 $self->_assert_bindval_matches_bindtype(@bind);
282 return ($sql, @bind);
286 sub _insert_SCALARREF { # literal SQL without bind
287 my ($self, $data) = @_;
293 my ($self, $data) = @_;
295 my (@values, @all_bind);
296 foreach my $column (sort keys %$data) {
297 my $v = $data->{$column};
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);
342 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
343 return ($sql, @all_bind);
348 #======================================================================
350 #======================================================================
355 my $table = $self->_table(shift);
356 my $data = shift || return;
360 # first build the 'SET' part of the sql statement
361 my (@set, @all_bind);
362 puke "Unsupported data type specified to \$sql->update"
363 unless ref $data eq 'HASH';
365 for my $k (sort keys %$data) {
368 my $label = $self->_quote($k);
370 $self->_SWITCH_refkind($v, {
372 if ($self->{array_datatypes}) { # array datatype
373 push @set, "$label = ?";
374 push @all_bind, $self->_bindtype($k, $v);
376 else { # literal SQL with bind
377 my ($sql, @bind) = @$v;
378 $self->_assert_bindval_matches_bindtype(@bind);
379 push @set, "$label = $sql";
380 push @all_bind, @bind;
383 ARRAYREFREF => sub { # literal SQL with bind
384 my ($sql, @bind) = @${$v};
385 $self->_assert_bindval_matches_bindtype(@bind);
386 push @set, "$label = $sql";
387 push @all_bind, @bind;
389 SCALARREF => sub { # literal SQL without bind
390 push @set, "$label = $$v";
393 my ($op, $arg, @rest) = %$v;
395 puke 'Operator calls in update must be in the form { -op => $arg }'
396 if (@rest or not $op =~ /^\-(.+)/);
398 local $self->{_nested_func_lhs} = $k;
399 my ($sql, @bind) = $self->_where_unary_op ($1, $arg);
401 push @set, "$label = $sql";
402 push @all_bind, @bind;
404 SCALAR_or_UNDEF => sub {
405 push @set, "$label = ?";
406 push @all_bind, $self->_bindtype($k, $v);
412 my $sql = $self->_sqlcase('update') . " $table " . $self->_sqlcase('set ')
416 my($where_sql, @where_bind) = $self->where($where);
418 push @all_bind, @where_bind;
421 if ($options->{returning}) {
422 my ($returning_sql, @returning_bind) = $self->_update_returning ($options);
423 $sql .= $returning_sql;
424 push @all_bind, @returning_bind;
427 return wantarray ? ($sql, @all_bind) : $sql;
430 sub _update_returning { shift->_returning(@_) }
434 #======================================================================
436 #======================================================================
441 my $table = $self->_table(shift);
442 my $fields = shift || '*';
446 my($where_sql, @bind) = $self->where($where, $order);
448 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
450 my $sql = join(' ', $self->_sqlcase('select'), $f,
451 $self->_sqlcase('from'), $table)
454 return wantarray ? ($sql, @bind) : $sql;
457 #======================================================================
459 #======================================================================
464 my $table = $self->_table(shift);
468 my($where_sql, @bind) = $self->where($where);
469 my $sql = $self->_sqlcase('delete from') . " $table" . $where_sql;
471 return wantarray ? ($sql, @bind) : $sql;
475 #======================================================================
477 #======================================================================
481 # Finally, a separate routine just to handle WHERE clauses
483 my ($self, $where, $order) = @_;
486 my ($sql, @bind) = $self->_recurse_where($where);
487 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
491 my ($order_sql, @order_bind) = $self->_order_by($order);
493 push @bind, @order_bind;
496 return wantarray ? ($sql, @bind) : $sql;
501 my ($self, $where, $logic) = @_;
503 # dispatch on appropriate method according to refkind of $where
504 my $method = $self->_METHOD_FOR_refkind("_where", $where);
506 my ($sql, @bind) = $self->$method($where, $logic);
508 # DBIx::Class used to call _recurse_where in scalar context
509 # something else might too...
511 return ($sql, @bind);
514 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
521 #======================================================================
522 # WHERE: top-level ARRAYREF
523 #======================================================================
526 sub _where_ARRAYREF {
527 my ($self, $where, $logic) = @_;
529 $logic = uc($logic || $self->{logic});
530 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
532 my @clauses = @$where;
534 my (@sql_clauses, @all_bind);
535 # need to use while() so can shift() for pairs
537 my $el = shift @clauses;
539 $el = undef if (defined $el and ! length $el);
541 # switch according to kind of $el and get corresponding ($sql, @bind)
542 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
544 # skip empty elements, otherwise get invalid trailing AND stuff
545 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
549 $self->_assert_bindval_matches_bindtype(@b);
553 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
555 SCALARREF => sub { ($$el); },
558 # top-level arrayref with scalars, recurse in pairs
559 $self->_recurse_where({$el => shift(@clauses)})
562 UNDEF => sub {puke "Supplying an empty left hand side argument is not supported in array-pairs" },
566 push @sql_clauses, $sql;
567 push @all_bind, @bind;
571 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
574 #======================================================================
575 # WHERE: top-level ARRAYREFREF
576 #======================================================================
578 sub _where_ARRAYREFREF {
579 my ($self, $where) = @_;
580 my ($sql, @bind) = @$$where;
581 $self->_assert_bindval_matches_bindtype(@bind);
582 return ($sql, @bind);
585 #======================================================================
586 # WHERE: top-level HASHREF
587 #======================================================================
590 my ($self, $where) = @_;
591 my (@sql_clauses, @all_bind);
593 for my $k (sort keys %$where) {
594 my $v = $where->{$k};
596 # ($k => $v) is either a special unary op or a regular hashpair
597 my ($sql, @bind) = do {
599 # put the operator in canonical form
601 $op = substr $op, 1; # remove initial dash
602 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
603 $op =~ s/\s+/ /g; # compress whitespace
605 # so that -not_foo works correctly
606 $op =~ s/^not_/NOT /i;
608 $self->_debug("Unary OP(-$op) within hashref, recursing...");
609 my ($s, @b) = $self->_where_unary_op ($op, $v);
611 # top level vs nested
612 # we assume that handled unary ops will take care of their ()s
614 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
616 ( defined $self->{_nested_func_lhs} and $self->{_nested_func_lhs} eq $k )
622 if (is_literal_value ($v) ) {
623 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
626 puke "Supplying an empty left hand side argument is not supported in hash-pairs";
630 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
631 $self->$method($k, $v);
635 push @sql_clauses, $sql;
636 push @all_bind, @bind;
639 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
642 sub _where_unary_op {
643 my ($self, $op, $rhs) = @_;
645 # top level special ops are illegal in general
646 # this includes the -ident/-value ops (dual purpose unary and special)
647 puke "Illegal use of top-level '-$op'"
648 if ! defined $self->{_nested_func_lhs} and List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}};
650 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
651 my $handler = $op_entry->{handler};
653 if (not ref $handler) {
654 if ($op =~ s/ [_\s]? \d+ $//x ) {
655 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
656 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
658 return $self->$handler ($op, $rhs);
660 elsif (ref $handler eq 'CODE') {
661 return $handler->($self, $op, $rhs);
664 puke "Illegal handler for operator $op - expecting a method name or a coderef";
668 $self->_debug("Generic unary OP: $op - recursing as function");
670 $self->_assert_pass_injection_guard($op);
672 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
674 puke "Illegal use of top-level '-$op'"
675 unless defined $self->{_nested_func_lhs};
678 $self->_convert('?'),
679 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
683 $self->_recurse_where ($rhs)
687 $sql = sprintf ('%s %s',
688 $self->_sqlcase($op),
692 return ($sql, @bind);
695 sub _where_op_ANDOR {
696 my ($self, $op, $v) = @_;
698 $self->_SWITCH_refkind($v, {
700 return $self->_where_ARRAYREF($v, $op);
704 return ( $op =~ /^or/i )
705 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
706 : $self->_where_HASHREF($v);
710 puke "-$op => \\\$scalar makes little sense, use " .
712 ? '[ \$scalar, \%rest_of_conditions ] instead'
713 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
718 puke "-$op => \\[...] makes little sense, use " .
720 ? '[ \[...], \%rest_of_conditions ] instead'
721 : '-and => [ \[...], \%rest_of_conditions ] instead'
725 SCALAR => sub { # permissively interpreted as SQL
726 puke "-$op => \$value makes little sense, use -bool => \$value instead";
730 puke "-$op => undef not supported";
736 my ($self, $op, $v) = @_;
738 $self->_SWITCH_refkind($v, {
740 SCALAR => sub { # permissively interpreted as SQL
741 belch "literal SQL should be -nest => \\'scalar' "
742 . "instead of -nest => 'scalar' ";
747 puke "-$op => undef not supported";
751 $self->_recurse_where ($v);
759 my ($self, $op, $v) = @_;
761 my ($s, @b) = $self->_SWITCH_refkind($v, {
762 SCALAR => sub { # interpreted as SQL column
763 $self->_convert($self->_quote($v));
767 puke "-$op => undef not supported";
771 $self->_recurse_where ($v);
775 $s = "(NOT $s)" if $op =~ /^not/i;
780 sub _where_op_IDENT {
782 my ($op, $rhs) = splice @_, -2;
783 if (! defined $rhs or length ref $rhs) {
784 puke "-$op requires a single plain scalar argument (a quotable identifier)";
787 # in case we are called as a top level special op (no '=')
790 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
798 sub _where_op_VALUE {
800 my ($op, $rhs) = splice @_, -2;
802 # in case we are called as a top level special op (no '=')
806 if (! defined $rhs) {
808 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
815 ( defined $lhs ? $lhs : $self->{_nested_func_lhs} ),
822 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
826 $self->_convert('?'),
832 sub _where_hashpair_ARRAYREF {
833 my ($self, $k, $v) = @_;
836 my @v = @$v; # need copy because of shift below
837 $self->_debug("ARRAY($k) means distribute over elements");
839 # put apart first element if it is an operator (-and, -or)
841 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
845 my @distributed = map { {$k => $_} } @v;
848 $self->_debug("OP($op) reinjected into the distributed array");
849 unshift @distributed, $op;
852 my $logic = $op ? substr($op, 1) : '';
854 return $self->_recurse_where(\@distributed, $logic);
857 $self->_debug("empty ARRAY($k) means 0=1");
858 return ($self->{sqlfalse});
862 sub _where_hashpair_HASHREF {
863 my ($self, $k, $v, $logic) = @_;
866 local $self->{_nested_func_lhs} = defined $self->{_nested_func_lhs}
867 ? $self->{_nested_func_lhs}
871 my ($all_sql, @all_bind);
873 for my $orig_op (sort keys %$v) {
874 my $val = $v->{$orig_op};
876 # put the operator in canonical form
879 # FIXME - we need to phase out dash-less ops
880 $op =~ s/^-//; # remove possible initial dash
881 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
882 $op =~ s/\s+/ /g; # compress whitespace
884 $self->_assert_pass_injection_guard($op);
887 $op =~ s/^is_not/IS NOT/i;
889 # so that -not_foo works correctly
890 $op =~ s/^not_/NOT /i;
892 # another retarded special case: foo => { $op => { -value => undef } }
893 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
899 # CASE: col-value logic modifiers
900 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
901 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
903 # CASE: special operators like -in or -between
904 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
905 my $handler = $special_op->{handler};
907 puke "No handler supplied for special operator $orig_op";
909 elsif (not ref $handler) {
910 ($sql, @bind) = $self->$handler ($k, $op, $val);
912 elsif (ref $handler eq 'CODE') {
913 ($sql, @bind) = $handler->($self, $k, $op, $val);
916 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
920 $self->_SWITCH_refkind($val, {
922 ARRAYREF => sub { # CASE: col => {op => \@vals}
923 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
926 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
927 my ($sub_sql, @sub_bind) = @$$val;
928 $self->_assert_bindval_matches_bindtype(@sub_bind);
929 $sql = join ' ', $self->_convert($self->_quote($k)),
930 $self->_sqlcase($op),
935 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
937 $op =~ /^not$/i ? 'is not' # legacy
938 : $op =~ $self->{equality_op} ? 'is'
939 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
940 : $op =~ $self->{inequality_op} ? 'is not'
941 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
942 : puke "unexpected operator '$orig_op' with undef operand";
944 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
947 FALLBACK => sub { # CASE: col => {op/func => $stuff}
948 ($sql, @bind) = $self->_where_unary_op ($op, $val);
951 $self->_convert($self->_quote($k)),
952 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
958 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
959 push @all_bind, @bind;
961 return ($all_sql, @all_bind);
964 sub _where_field_IS {
965 my ($self, $k, $op, $v) = @_;
967 my ($s) = $self->_SWITCH_refkind($v, {
970 $self->_convert($self->_quote($k)),
971 map { $self->_sqlcase($_)} ($op, 'null')
974 puke "$op can only take undef as argument";
981 sub _where_field_op_ARRAYREF {
982 my ($self, $k, $op, $vals) = @_;
984 my @vals = @$vals; #always work on a copy
987 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
989 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
992 # see if the first element is an -and/-or op
994 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
999 # a long standing API wart - an attempt to change this behavior during
1000 # the 1.50 series failed *spectacularly*. Warn instead and leave the
1005 (!$logic or $logic eq 'OR')
1007 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
1010 belch "A multi-element arrayref as an argument to the inequality op '$o' "
1011 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
1012 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
1016 # distribute $op over each remaining member of @vals, append logic if exists
1017 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
1021 # try to DWIM on equality operators
1023 $op =~ $self->{equality_op} ? $self->{sqlfalse}
1024 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
1025 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
1026 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
1027 : puke "operator '$op' applied on an empty array (field '$k')";
1032 sub _where_hashpair_SCALARREF {
1033 my ($self, $k, $v) = @_;
1034 $self->_debug("SCALAR($k) means literal SQL: $$v");
1035 my $sql = $self->_quote($k) . " " . $$v;
1039 # literal SQL with bind
1040 sub _where_hashpair_ARRAYREFREF {
1041 my ($self, $k, $v) = @_;
1042 $self->_debug("REF($k) means literal SQL: @${$v}");
1043 my ($sql, @bind) = @$$v;
1044 $self->_assert_bindval_matches_bindtype(@bind);
1045 $sql = $self->_quote($k) . " " . $sql;
1046 return ($sql, @bind );
1049 # literal SQL without bind
1050 sub _where_hashpair_SCALAR {
1051 my ($self, $k, $v) = @_;
1052 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
1053 my $sql = join ' ', $self->_convert($self->_quote($k)),
1054 $self->_sqlcase($self->{cmp}),
1055 $self->_convert('?');
1056 my @bind = $self->_bindtype($k, $v);
1057 return ( $sql, @bind);
1061 sub _where_hashpair_UNDEF {
1062 my ($self, $k, $v) = @_;
1063 $self->_debug("UNDEF($k) means IS NULL");
1064 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
1068 #======================================================================
1069 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
1070 #======================================================================
1073 sub _where_SCALARREF {
1074 my ($self, $where) = @_;
1077 $self->_debug("SCALAR(*top) means literal SQL: $$where");
1083 my ($self, $where) = @_;
1086 $self->_debug("NOREF(*top) means literal SQL: $where");
1097 #======================================================================
1098 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
1099 #======================================================================
1102 sub _where_field_BETWEEN {
1103 my ($self, $k, $op, $vals) = @_;
1105 my ($label, $and, $placeholder);
1106 $label = $self->_convert($self->_quote($k));
1107 $and = ' ' . $self->_sqlcase('and') . ' ';
1108 $placeholder = $self->_convert('?');
1109 $op = $self->_sqlcase($op);
1111 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1113 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1114 ARRAYREFREF => sub {
1115 my ($s, @b) = @$$vals;
1116 $self->_assert_bindval_matches_bindtype(@b);
1123 puke $invalid_args if @$vals != 2;
1125 my (@all_sql, @all_bind);
1126 foreach my $val (@$vals) {
1127 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1129 return ($placeholder, $self->_bindtype($k, $val) );
1134 ARRAYREFREF => sub {
1135 my ($sql, @bind) = @$$val;
1136 $self->_assert_bindval_matches_bindtype(@bind);
1137 return ($sql, @bind);
1140 my ($func, $arg, @rest) = %$val;
1141 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1142 if (@rest or $func !~ /^ \- (.+)/x);
1143 $self->_where_unary_op ($1 => $arg);
1149 push @all_sql, $sql;
1150 push @all_bind, @bind;
1154 (join $and, @all_sql),
1163 my $sql = "( $label $op $clause )";
1164 return ($sql, @bind)
1168 sub _where_field_IN {
1169 my ($self, $k, $op, $vals) = @_;
1171 # backwards compatibility : if scalar, force into an arrayref
1172 $vals = [$vals] if defined $vals && ! ref $vals;
1174 my ($label) = $self->_convert($self->_quote($k));
1175 my ($placeholder) = $self->_convert('?');
1176 $op = $self->_sqlcase($op);
1178 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1179 ARRAYREF => sub { # list of choices
1180 if (@$vals) { # nonempty list
1181 my (@all_sql, @all_bind);
1183 for my $val (@$vals) {
1184 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1186 return ($placeholder, $val);
1191 ARRAYREFREF => sub {
1192 my ($sql, @bind) = @$$val;
1193 $self->_assert_bindval_matches_bindtype(@bind);
1194 return ($sql, @bind);
1197 my ($func, $arg, @rest) = %$val;
1198 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1199 if (@rest or $func !~ /^ \- (.+)/x);
1200 $self->_where_unary_op ($1 => $arg);
1204 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1205 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1206 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1207 . 'will emit the logically correct SQL instead of raising this exception)'
1211 push @all_sql, $sql;
1212 push @all_bind, @bind;
1216 sprintf ('%s %s ( %s )',
1219 join (', ', @all_sql)
1221 $self->_bindtype($k, @all_bind),
1224 else { # empty list : some databases won't understand "IN ()", so DWIM
1225 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1230 SCALARREF => sub { # literal SQL
1231 my $sql = $self->_open_outer_paren ($$vals);
1232 return ("$label $op ( $sql )");
1234 ARRAYREFREF => sub { # literal SQL with bind
1235 my ($sql, @bind) = @$$vals;
1236 $self->_assert_bindval_matches_bindtype(@bind);
1237 $sql = $self->_open_outer_paren ($sql);
1238 return ("$label $op ( $sql )", @bind);
1242 puke "Argument passed to the '$op' operator can not be undefined";
1246 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1250 return ($sql, @bind);
1253 # Some databases (SQLite) treat col IN (1, 2) different from
1254 # col IN ( (1, 2) ). Use this to strip all outer parens while
1255 # adding them back in the corresponding method
1256 sub _open_outer_paren {
1257 my ($self, $sql) = @_;
1259 while ( my ($inner) = $sql =~ /^ \s* \( (.*) \) \s* $/xs ) {
1261 # there are closing parens inside, need the heavy duty machinery
1262 # to reevaluate the extraction starting from $sql (full reevaluation)
1263 if ( $inner =~ /\)/ ) {
1264 require Text::Balanced;
1266 my (undef, $remainder) = do {
1267 # idiotic design - writes to $@ but *DOES NOT* throw exceptions
1269 Text::Balanced::extract_bracketed( $sql, '()', qr/\s*/ );
1272 # the entire expression needs to be a balanced bracketed thing
1273 # (after an extract no remainder sans trailing space)
1274 last if defined $remainder and $remainder =~ /\S/;
1284 #======================================================================
1286 #======================================================================
1289 my ($self, $arg) = @_;
1292 for my $c ($self->_order_by_chunks ($arg) ) {
1293 $self->_SWITCH_refkind ($c, {
1294 SCALAR => sub { push @sql, $c },
1295 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1301 $self->_sqlcase(' order by'),
1307 return wantarray ? ($sql, @bind) : $sql;
1310 sub _order_by_chunks {
1311 my ($self, $arg) = @_;
1313 return $self->_SWITCH_refkind($arg, {
1316 map { $self->_order_by_chunks ($_ ) } @$arg;
1319 ARRAYREFREF => sub {
1320 my ($s, @b) = @$$arg;
1321 $self->_assert_bindval_matches_bindtype(@b);
1325 SCALAR => sub {$self->_quote($arg)},
1327 UNDEF => sub {return () },
1329 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1332 # get first pair in hash
1333 my ($key, $val, @rest) = %$arg;
1335 return () unless $key;
1337 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1338 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1344 for my $c ($self->_order_by_chunks ($val)) {
1347 $self->_SWITCH_refkind ($c, {
1352 ($sql, @bind) = @$c;
1356 $sql = $sql . ' ' . $self->_sqlcase($direction);
1358 push @ret, [ $sql, @bind];
1367 #======================================================================
1368 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1369 #======================================================================
1374 $self->_SWITCH_refkind($from, {
1375 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1376 SCALAR => sub {$self->_quote($from)},
1377 SCALARREF => sub {$$from},
1382 #======================================================================
1384 #======================================================================
1386 # highly optimized, as it's called way too often
1388 # my ($self, $label) = @_;
1390 return '' unless defined $_[1];
1391 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1393 $_[0]->{quote_char} or
1394 ($_[0]->_assert_pass_injection_guard($_[1]), return $_[1]);
1396 my $qref = ref $_[0]->{quote_char};
1398 !$qref ? ($_[0]->{quote_char}, $_[0]->{quote_char})
1399 : ($qref eq 'ARRAY') ? @{$_[0]->{quote_char}}
1400 : puke "Unsupported quote_char format: $_[0]->{quote_char}";
1402 my $esc = $_[0]->{escape_char} || $r;
1404 # parts containing * are naturally unquoted
1405 return join( $_[0]->{name_sep}||'', map
1406 +( $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } ),
1407 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1412 # Conversion, if applicable
1414 #my ($self, $arg) = @_;
1415 if ($_[0]->{convert}) {
1416 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1423 #my ($self, $col, @vals) = @_;
1424 # called often - tighten code
1425 return $_[0]->{bindtype} eq 'columns'
1426 ? map {[$_[1], $_]} @_[2 .. $#_]
1431 # Dies if any element of @bind is not in [colname => value] format
1432 # if bindtype is 'columns'.
1433 sub _assert_bindval_matches_bindtype {
1434 # my ($self, @bind) = @_;
1436 if ($self->{bindtype} eq 'columns') {
1438 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1439 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1445 sub _join_sql_clauses {
1446 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1448 if (@$clauses_aref > 1) {
1449 my $join = " " . $self->_sqlcase($logic) . " ";
1450 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1451 return ($sql, @$bind_aref);
1453 elsif (@$clauses_aref) {
1454 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1457 return (); # if no SQL, ignore @$bind_aref
1462 # Fix SQL case, if so requested
1464 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1465 # don't touch the argument ... crooked logic, but let's not change it!
1466 return $_[0]->{case} ? $_[1] : uc($_[1]);
1470 #======================================================================
1471 # DISPATCHING FROM REFKIND
1472 #======================================================================
1475 my ($self, $data) = @_;
1477 return 'UNDEF' unless defined $data;
1479 # blessed objects are treated like scalars
1480 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1482 return 'SCALAR' unless $ref;
1485 while ($ref eq 'REF') {
1487 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1491 return ($ref||'SCALAR') . ('REF' x $n_steps);
1495 my ($self, $data) = @_;
1496 my @try = ($self->_refkind($data));
1497 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1498 push @try, 'FALLBACK';
1502 sub _METHOD_FOR_refkind {
1503 my ($self, $meth_prefix, $data) = @_;
1506 for (@{$self->_try_refkind($data)}) {
1507 $method = $self->can($meth_prefix."_".$_)
1511 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1515 sub _SWITCH_refkind {
1516 my ($self, $data, $dispatch_table) = @_;
1519 for (@{$self->_try_refkind($data)}) {
1520 $coderef = $dispatch_table->{$_}
1524 puke "no dispatch entry for ".$self->_refkind($data)
1533 #======================================================================
1534 # VALUES, GENERATE, AUTOLOAD
1535 #======================================================================
1537 # LDNOTE: original code from nwiger, didn't touch code in that section
1538 # I feel the AUTOLOAD stuff should not be the default, it should
1539 # only be activated on explicit demand by user.
1543 my $data = shift || return;
1544 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1545 unless ref $data eq 'HASH';
1548 foreach my $k ( sort keys %$data ) {
1549 my $v = $data->{$k};
1550 $self->_SWITCH_refkind($v, {
1552 if ($self->{array_datatypes}) { # array datatype
1553 push @all_bind, $self->_bindtype($k, $v);
1555 else { # literal SQL with bind
1556 my ($sql, @bind) = @$v;
1557 $self->_assert_bindval_matches_bindtype(@bind);
1558 push @all_bind, @bind;
1561 ARRAYREFREF => sub { # literal SQL with bind
1562 my ($sql, @bind) = @${$v};
1563 $self->_assert_bindval_matches_bindtype(@bind);
1564 push @all_bind, @bind;
1566 SCALARREF => sub { # literal SQL without bind
1568 SCALAR_or_UNDEF => sub {
1569 push @all_bind, $self->_bindtype($k, $v);
1580 my(@sql, @sqlq, @sqlv);
1584 if ($ref eq 'HASH') {
1585 for my $k (sort keys %$_) {
1588 my $label = $self->_quote($k);
1589 if ($r eq 'ARRAY') {
1590 # literal SQL with bind
1591 my ($sql, @bind) = @$v;
1592 $self->_assert_bindval_matches_bindtype(@bind);
1593 push @sqlq, "$label = $sql";
1595 } elsif ($r eq 'SCALAR') {
1596 # literal SQL without bind
1597 push @sqlq, "$label = $$v";
1599 push @sqlq, "$label = ?";
1600 push @sqlv, $self->_bindtype($k, $v);
1603 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1604 } elsif ($ref eq 'ARRAY') {
1605 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1608 if ($r eq 'ARRAY') { # literal SQL with bind
1609 my ($sql, @bind) = @$v;
1610 $self->_assert_bindval_matches_bindtype(@bind);
1613 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1614 # embedded literal SQL
1621 push @sql, '(' . join(', ', @sqlq) . ')';
1622 } elsif ($ref eq 'SCALAR') {
1626 # strings get case twiddled
1627 push @sql, $self->_sqlcase($_);
1631 my $sql = join ' ', @sql;
1633 # this is pretty tricky
1634 # if ask for an array, return ($stmt, @bind)
1635 # otherwise, s/?/shift @sqlv/ to put it inline
1637 return ($sql, @sqlv);
1639 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1640 ref $d ? $d->[1] : $d/e;
1649 # This allows us to check for a local, then _form, attr
1651 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1652 return $self->generate($name, @_);
1663 SQL::Abstract - Generate SQL from Perl data structures
1669 my $sql = SQL::Abstract->new;
1671 my($stmt, @bind) = $sql->select($source, \@fields, \%where, $order);
1673 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1675 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1677 my($stmt, @bind) = $sql->delete($table, \%where);
1679 # Then, use these in your DBI statements
1680 my $sth = $dbh->prepare($stmt);
1681 $sth->execute(@bind);
1683 # Just generate the WHERE clause
1684 my($stmt, @bind) = $sql->where(\%where, $order);
1686 # Return values in the same order, for hashed queries
1687 # See PERFORMANCE section for more details
1688 my @bind = $sql->values(\%fieldvals);
1692 This module was inspired by the excellent L<DBIx::Abstract>.
1693 However, in using that module I found that what I really wanted
1694 to do was generate SQL, but still retain complete control over my
1695 statement handles and use the DBI interface. So, I set out to
1696 create an abstract SQL generation module.
1698 While based on the concepts used by L<DBIx::Abstract>, there are
1699 several important differences, especially when it comes to WHERE
1700 clauses. I have modified the concepts used to make the SQL easier
1701 to generate from Perl data structures and, IMO, more intuitive.
1702 The underlying idea is for this module to do what you mean, based
1703 on the data structures you provide it. The big advantage is that
1704 you don't have to modify your code every time your data changes,
1705 as this module figures it out.
1707 To begin with, an SQL INSERT is as easy as just specifying a hash
1708 of C<key=value> pairs:
1711 name => 'Jimbo Bobson',
1712 phone => '123-456-7890',
1713 address => '42 Sister Lane',
1714 city => 'St. Louis',
1715 state => 'Louisiana',
1718 The SQL can then be generated with this:
1720 my($stmt, @bind) = $sql->insert('people', \%data);
1722 Which would give you something like this:
1724 $stmt = "INSERT INTO people
1725 (address, city, name, phone, state)
1726 VALUES (?, ?, ?, ?, ?)";
1727 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1728 '123-456-7890', 'Louisiana');
1730 These are then used directly in your DBI code:
1732 my $sth = $dbh->prepare($stmt);
1733 $sth->execute(@bind);
1735 =head2 Inserting and Updating Arrays
1737 If your database has array types (like for example Postgres),
1738 activate the special option C<< array_datatypes => 1 >>
1739 when creating the C<SQL::Abstract> object.
1740 Then you may use an arrayref to insert and update database array types:
1742 my $sql = SQL::Abstract->new(array_datatypes => 1);
1744 planets => [qw/Mercury Venus Earth Mars/]
1747 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1751 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1753 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1756 =head2 Inserting and Updating SQL
1758 In order to apply SQL functions to elements of your C<%data> you may
1759 specify a reference to an arrayref for the given hash value. For example,
1760 if you need to execute the Oracle C<to_date> function on a value, you can
1761 say something like this:
1765 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1768 The first value in the array is the actual SQL. Any other values are
1769 optional and would be included in the bind values array. This gives
1772 my($stmt, @bind) = $sql->insert('people', \%data);
1774 $stmt = "INSERT INTO people (name, date_entered)
1775 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1776 @bind = ('Bill', '03/02/2003');
1778 An UPDATE is just as easy, all you change is the name of the function:
1780 my($stmt, @bind) = $sql->update('people', \%data);
1782 Notice that your C<%data> isn't touched; the module will generate
1783 the appropriately quirky SQL for you automatically. Usually you'll
1784 want to specify a WHERE clause for your UPDATE, though, which is
1785 where handling C<%where> hashes comes in handy...
1787 =head2 Complex where statements
1789 This module can generate pretty complicated WHERE statements
1790 easily. For example, simple C<key=value> pairs are taken to mean
1791 equality, and if you want to see if a field is within a set
1792 of values, you can use an arrayref. Let's say we wanted to
1793 SELECT some data based on this criteria:
1796 requestor => 'inna',
1797 worker => ['nwiger', 'rcwe', 'sfz'],
1798 status => { '!=', 'completed' }
1801 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1803 The above would give you something like this:
1805 $stmt = "SELECT * FROM tickets WHERE
1806 ( requestor = ? ) AND ( status != ? )
1807 AND ( worker = ? OR worker = ? OR worker = ? )";
1808 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1810 Which you could then use in DBI code like so:
1812 my $sth = $dbh->prepare($stmt);
1813 $sth->execute(@bind);
1819 The methods are simple. There's one for every major SQL operation,
1820 and a constructor you use first. The arguments are specified in a
1821 similar order for each method (table, then fields, then a where
1822 clause) to try and simplify things.
1824 =head2 new(option => 'value')
1826 The C<new()> function takes a list of options and values, and returns
1827 a new B<SQL::Abstract> object which can then be used to generate SQL
1828 through the methods below. The options accepted are:
1834 If set to 'lower', then SQL will be generated in all lowercase. By
1835 default SQL is generated in "textbook" case meaning something like:
1837 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1839 Any setting other than 'lower' is ignored.
1843 This determines what the default comparison operator is. By default
1844 it is C<=>, meaning that a hash like this:
1846 %where = (name => 'nwiger', email => 'nate@wiger.org');
1848 Will generate SQL like this:
1850 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1852 However, you may want loose comparisons by default, so if you set
1853 C<cmp> to C<like> you would get SQL such as:
1855 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1857 You can also override the comparison on an individual basis - see
1858 the huge section on L</"WHERE CLAUSES"> at the bottom.
1860 =item sqltrue, sqlfalse
1862 Expressions for inserting boolean values within SQL statements.
1863 By default these are C<1=1> and C<1=0>. They are used
1864 by the special operators C<-in> and C<-not_in> for generating
1865 correct SQL even when the argument is an empty array (see below).
1869 This determines the default logical operator for multiple WHERE
1870 statements in arrays or hashes. If absent, the default logic is "or"
1871 for arrays, and "and" for hashes. This means that a WHERE
1875 event_date => {'>=', '2/13/99'},
1876 event_date => {'<=', '4/24/03'},
1879 will generate SQL like this:
1881 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1883 This is probably not what you want given this query, though (look
1884 at the dates). To change the "OR" to an "AND", simply specify:
1886 my $sql = SQL::Abstract->new(logic => 'and');
1888 Which will change the above C<WHERE> to:
1890 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1892 The logic can also be changed locally by inserting
1893 a modifier in front of an arrayref :
1895 @where = (-and => [event_date => {'>=', '2/13/99'},
1896 event_date => {'<=', '4/24/03'} ]);
1898 See the L</"WHERE CLAUSES"> section for explanations.
1902 This will automatically convert comparisons using the specified SQL
1903 function for both column and value. This is mostly used with an argument
1904 of C<upper> or C<lower>, so that the SQL will have the effect of
1905 case-insensitive "searches". For example, this:
1907 $sql = SQL::Abstract->new(convert => 'upper');
1908 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1910 Will turn out the following SQL:
1912 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1914 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1915 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1916 not validate this option; it will just pass through what you specify verbatim).
1920 This is a kludge because many databases suck. For example, you can't
1921 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1922 Instead, you have to use C<bind_param()>:
1924 $sth->bind_param(1, 'reg data');
1925 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1927 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1928 which loses track of which field each slot refers to. Fear not.
1930 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1931 Currently, you can specify either C<normal> (default) or C<columns>. If you
1932 specify C<columns>, you will get an array that looks like this:
1934 my $sql = SQL::Abstract->new(bindtype => 'columns');
1935 my($stmt, @bind) = $sql->insert(...);
1938 [ 'column1', 'value1' ],
1939 [ 'column2', 'value2' ],
1940 [ 'column3', 'value3' ],
1943 You can then iterate through this manually, using DBI's C<bind_param()>.
1945 $sth->prepare($stmt);
1948 my($col, $data) = @$_;
1949 if ($col eq 'details' || $col eq 'comments') {
1950 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1951 } elsif ($col eq 'image') {
1952 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1954 $sth->bind_param($i, $data);
1958 $sth->execute; # execute without @bind now
1960 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1961 Basically, the advantage is still that you don't have to care which fields
1962 are or are not included. You could wrap that above C<for> loop in a simple
1963 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1964 get a layer of abstraction over manual SQL specification.
1966 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1967 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1968 will expect the bind values in this format.
1972 This is the character that a table or column name will be quoted
1973 with. By default this is an empty string, but you could set it to
1974 the character C<`>, to generate SQL like this:
1976 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1978 Alternatively, you can supply an array ref of two items, the first being the left
1979 hand quote character, and the second the right hand quote character. For
1980 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1981 that generates SQL like this:
1983 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1985 Quoting is useful if you have tables or columns names that are reserved
1986 words in your database's SQL dialect.
1990 This is the character that will be used to escape L</quote_char>s appearing
1991 in an identifier before it has been quoted.
1993 The parameter default in case of a single L</quote_char> character is the quote
1996 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1997 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
1998 of the B<opening (left)> L</quote_char> within the identifier are currently left
1999 untouched. The default for opening-closing-style quotes may change in future
2000 versions, thus you are B<strongly encouraged> to specify the escape character
2005 This is the character that separates a table and column name. It is
2006 necessary to specify this when the C<quote_char> option is selected,
2007 so that tables and column names can be individually quoted like this:
2009 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
2011 =item injection_guard
2013 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
2014 column name specified in a query structure. This is a safety mechanism to avoid
2015 injection attacks when mishandling user input e.g.:
2017 my %condition_as_column_value_pairs = get_values_from_user();
2018 $sqla->select( ... , \%condition_as_column_value_pairs );
2020 If the expression matches an exception is thrown. Note that literal SQL
2021 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
2023 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
2025 =item array_datatypes
2027 When this option is true, arrayrefs in INSERT or UPDATE are
2028 interpreted as array datatypes and are passed directly
2030 When this option is false, arrayrefs are interpreted
2031 as literal SQL, just like refs to arrayrefs
2032 (but this behavior is for backwards compatibility; when writing
2033 new queries, use the "reference to arrayref" syntax
2039 Takes a reference to a list of "special operators"
2040 to extend the syntax understood by L<SQL::Abstract>.
2041 See section L</"SPECIAL OPERATORS"> for details.
2045 Takes a reference to a list of "unary operators"
2046 to extend the syntax understood by L<SQL::Abstract>.
2047 See section L</"UNARY OPERATORS"> for details.
2053 =head2 insert($table, \@values || \%fieldvals, \%options)
2055 This is the simplest function. You simply give it a table name
2056 and either an arrayref of values or hashref of field/value pairs.
2057 It returns an SQL INSERT statement and a list of bind values.
2058 See the sections on L</"Inserting and Updating Arrays"> and
2059 L</"Inserting and Updating SQL"> for information on how to insert
2060 with those data types.
2062 The optional C<\%options> hash reference may contain additional
2063 options to generate the insert SQL. Currently supported options
2070 Takes either a scalar of raw SQL fields, or an array reference of
2071 field names, and adds on an SQL C<RETURNING> statement at the end.
2072 This allows you to return data generated by the insert statement
2073 (such as row IDs) without performing another C<SELECT> statement.
2074 Note, however, this is not part of the SQL standard and may not
2075 be supported by all database engines.
2079 =head2 update($table, \%fieldvals, \%where, \%options)
2081 This takes a table, hashref of field/value pairs, and an optional
2082 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
2084 See the sections on L</"Inserting and Updating Arrays"> and
2085 L</"Inserting and Updating SQL"> for information on how to insert
2086 with those data types.
2088 The optional C<\%options> hash reference may contain additional
2089 options to generate the update SQL. Currently supported options
2096 See the C<returning> option to
2097 L<insert|/insert($table, \@values || \%fieldvals, \%options)>.
2101 =head2 select($source, $fields, $where, $order)
2103 This returns a SQL SELECT statement and associated list of bind values, as
2104 specified by the arguments :
2110 Specification of the 'FROM' part of the statement.
2111 The argument can be either a plain scalar (interpreted as a table
2112 name, will be quoted), or an arrayref (interpreted as a list
2113 of table names, joined by commas, quoted), or a scalarref
2114 (literal table name, not quoted), or a ref to an arrayref
2115 (list of literal table names, joined by commas, not quoted).
2119 Specification of the list of fields to retrieve from
2121 The argument can be either an arrayref (interpreted as a list
2122 of field names, will be joined by commas and quoted), or a
2123 plain scalar (literal SQL, not quoted).
2124 Please observe that this API is not as flexible as that of
2125 the first argument C<$source>, for backwards compatibility reasons.
2129 Optional argument to specify the WHERE part of the query.
2130 The argument is most often a hashref, but can also be
2131 an arrayref or plain scalar --
2132 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2136 Optional argument to specify the ORDER BY part of the query.
2137 The argument can be a scalar, a hashref or an arrayref
2138 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2144 =head2 delete($table, \%where)
2146 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2147 It returns an SQL DELETE statement and list of bind values.
2149 =head2 where(\%where, $order)
2151 This is used to generate just the WHERE clause. For example,
2152 if you have an arbitrary data structure and know what the
2153 rest of your SQL is going to look like, but want an easy way
2154 to produce a WHERE clause, use this. It returns an SQL WHERE
2155 clause and list of bind values.
2158 =head2 values(\%data)
2160 This just returns the values from the hash C<%data>, in the same
2161 order that would be returned from any of the other above queries.
2162 Using this allows you to markedly speed up your queries if you
2163 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2165 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2167 Warning: This is an experimental method and subject to change.
2169 This returns arbitrarily generated SQL. It's a really basic shortcut.
2170 It will return two different things, depending on return context:
2172 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2173 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2175 These would return the following:
2177 # First calling form
2178 $stmt = "CREATE TABLE test (?, ?)";
2179 @bind = (field1, field2);
2181 # Second calling form
2182 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2184 Depending on what you're trying to do, it's up to you to choose the correct
2185 format. In this example, the second form is what you would want.
2189 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2193 ALTER SESSION SET nls_date_format = 'MM/YY'
2195 You get the idea. Strings get their case twiddled, but everything
2196 else remains verbatim.
2198 =head1 EXPORTABLE FUNCTIONS
2200 =head2 is_plain_value
2202 Determines if the supplied argument is a plain value as understood by this
2207 =item * The value is C<undef>
2209 =item * The value is a non-reference
2211 =item * The value is an object with stringification overloading
2213 =item * The value is of the form C<< { -value => $anything } >>
2217 On failure returns C<undef>, on sucess returns a B<scalar> reference
2218 to the original supplied argument.
2224 The stringification overloading detection is rather advanced: it takes
2225 into consideration not only the presence of a C<""> overload, but if that
2226 fails also checks for enabled
2227 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2228 on either C<0+> or C<bool>.
2230 Unfortunately testing in the field indicates that this
2231 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2232 but only when very large numbers of stringifying objects are involved.
2233 At the time of writing ( Sep 2014 ) there is no clear explanation of
2234 the direct cause, nor is there a manageably small test case that reliably
2235 reproduces the problem.
2237 If you encounter any of the following exceptions in B<random places within
2238 your application stack> - this module may be to blame:
2240 Operation "ne": no method found,
2241 left argument in overloaded package <something>,
2242 right argument in overloaded package <something>
2246 Stub found while resolving method "???" overloading """" in package <something>
2248 If you fall victim to the above - please attempt to reduce the problem
2249 to something that could be sent to the L<SQL::Abstract developers
2250 |DBIx::Class/GETTING HELP/SUPPORT>
2251 (either publicly or privately). As a workaround in the meantime you can
2252 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2253 value, which will most likely eliminate your problem (at the expense of
2254 not being able to properly detect exotic forms of stringification).
2256 This notice and environment variable will be removed in a future version,
2257 as soon as the underlying problem is found and a reliable workaround is
2262 =head2 is_literal_value
2264 Determines if the supplied argument is a literal value as understood by this
2269 =item * C<\$sql_string>
2271 =item * C<\[ $sql_string, @bind_values ]>
2275 On failure returns C<undef>, on sucess returns an B<array> reference
2276 containing the unpacked version of the supplied literal SQL and bind values.
2278 =head1 WHERE CLAUSES
2282 This module uses a variation on the idea from L<DBIx::Abstract>. It
2283 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2284 module is that things in arrays are OR'ed, and things in hashes
2287 The easiest way to explain is to show lots of examples. After
2288 each C<%where> hash shown, it is assumed you used:
2290 my($stmt, @bind) = $sql->where(\%where);
2292 However, note that the C<%where> hash can be used directly in any
2293 of the other functions as well, as described above.
2295 =head2 Key-value pairs
2297 So, let's get started. To begin, a simple hash:
2301 status => 'completed'
2304 Is converted to SQL C<key = val> statements:
2306 $stmt = "WHERE user = ? AND status = ?";
2307 @bind = ('nwiger', 'completed');
2309 One common thing I end up doing is having a list of values that
2310 a field can be in. To do this, simply specify a list inside of
2315 status => ['assigned', 'in-progress', 'pending'];
2318 This simple code will create the following:
2320 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2321 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2323 A field associated to an empty arrayref will be considered a
2324 logical false and will generate 0=1.
2326 =head2 Tests for NULL values
2328 If the value part is C<undef> then this is converted to SQL <IS NULL>
2337 $stmt = "WHERE user = ? AND status IS NULL";
2340 To test if a column IS NOT NULL:
2344 status => { '!=', undef },
2347 =head2 Specific comparison operators
2349 If you want to specify a different type of operator for your comparison,
2350 you can use a hashref for a given column:
2354 status => { '!=', 'completed' }
2357 Which would generate:
2359 $stmt = "WHERE user = ? AND status != ?";
2360 @bind = ('nwiger', 'completed');
2362 To test against multiple values, just enclose the values in an arrayref:
2364 status => { '=', ['assigned', 'in-progress', 'pending'] };
2366 Which would give you:
2368 "WHERE status = ? OR status = ? OR status = ?"
2371 The hashref can also contain multiple pairs, in which case it is expanded
2372 into an C<AND> of its elements:
2376 status => { '!=', 'completed', -not_like => 'pending%' }
2379 # Or more dynamically, like from a form
2380 $where{user} = 'nwiger';
2381 $where{status}{'!='} = 'completed';
2382 $where{status}{'-not_like'} = 'pending%';
2384 # Both generate this
2385 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2386 @bind = ('nwiger', 'completed', 'pending%');
2389 To get an OR instead, you can combine it with the arrayref idea:
2393 priority => [ { '=', 2 }, { '>', 5 } ]
2396 Which would generate:
2398 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2399 @bind = ('2', '5', 'nwiger');
2401 If you want to include literal SQL (with or without bind values), just use a
2402 scalar reference or reference to an arrayref as the value:
2405 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2406 date_expires => { '<' => \"now()" }
2409 Which would generate:
2411 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2412 @bind = ('11/26/2008');
2415 =head2 Logic and nesting operators
2417 In the example above,
2418 there is a subtle trap if you want to say something like
2419 this (notice the C<AND>):
2421 WHERE priority != ? AND priority != ?
2423 Because, in Perl you I<can't> do this:
2425 priority => { '!=' => 2, '!=' => 1 }
2427 As the second C<!=> key will obliterate the first. The solution
2428 is to use the special C<-modifier> form inside an arrayref:
2430 priority => [ -and => {'!=', 2},
2434 Normally, these would be joined by C<OR>, but the modifier tells it
2435 to use C<AND> instead. (Hint: You can use this in conjunction with the
2436 C<logic> option to C<new()> in order to change the way your queries
2437 work by default.) B<Important:> Note that the C<-modifier> goes
2438 B<INSIDE> the arrayref, as an extra first element. This will
2439 B<NOT> do what you think it might:
2441 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2443 Here is a quick list of equivalencies, since there is some overlap:
2446 status => {'!=', 'completed', 'not like', 'pending%' }
2447 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2450 status => {'=', ['assigned', 'in-progress']}
2451 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2452 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2456 =head2 Special operators : IN, BETWEEN, etc.
2458 You can also use the hashref format to compare a list of fields using the
2459 C<IN> comparison operator, by specifying the list as an arrayref:
2462 status => 'completed',
2463 reportid => { -in => [567, 2335, 2] }
2466 Which would generate:
2468 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2469 @bind = ('completed', '567', '2335', '2');
2471 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2474 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2475 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2476 'sqltrue' (by default : C<1=1>).
2478 In addition to the array you can supply a chunk of literal sql or
2479 literal sql with bind:
2482 customer => { -in => \[
2483 'SELECT cust_id FROM cust WHERE balance > ?',
2486 status => { -in => \'SELECT status_codes FROM states' },
2492 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2493 AND status IN ( SELECT status_codes FROM states )
2497 Finally, if the argument to C<-in> is not a reference, it will be
2498 treated as a single-element array.
2500 Another pair of operators is C<-between> and C<-not_between>,
2501 used with an arrayref of two values:
2505 completion_date => {
2506 -not_between => ['2002-10-01', '2003-02-06']
2512 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2514 Just like with C<-in> all plausible combinations of literal SQL
2518 start0 => { -between => [ 1, 2 ] },
2519 start1 => { -between => \["? AND ?", 1, 2] },
2520 start2 => { -between => \"lower(x) AND upper(y)" },
2521 start3 => { -between => [
2523 \["upper(?)", 'stuff' ],
2530 ( start0 BETWEEN ? AND ? )
2531 AND ( start1 BETWEEN ? AND ? )
2532 AND ( start2 BETWEEN lower(x) AND upper(y) )
2533 AND ( start3 BETWEEN lower(x) AND upper(?) )
2535 @bind = (1, 2, 1, 2, 'stuff');
2538 These are the two builtin "special operators"; but the
2539 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2541 =head2 Unary operators: bool
2543 If you wish to test against boolean columns or functions within your
2544 database you can use the C<-bool> and C<-not_bool> operators. For
2545 example to test the column C<is_user> being true and the column
2546 C<is_enabled> being false you would use:-
2550 -not_bool => 'is_enabled',
2555 WHERE is_user AND NOT is_enabled
2557 If a more complex combination is required, testing more conditions,
2558 then you should use the and/or operators:-
2563 -not_bool => { two=> { -rlike => 'bar' } },
2564 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2575 (NOT ( three = ? OR three > ? ))
2578 =head2 Nested conditions, -and/-or prefixes
2580 So far, we've seen how multiple conditions are joined with a top-level
2581 C<AND>. We can change this by putting the different conditions we want in
2582 hashes and then putting those hashes in an array. For example:
2587 status => { -like => ['pending%', 'dispatched'] },
2591 status => 'unassigned',
2595 This data structure would create the following:
2597 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2598 OR ( user = ? AND status = ? ) )";
2599 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2602 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2603 to change the logic inside :
2609 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2610 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2617 $stmt = "WHERE ( user = ?
2618 AND ( ( workhrs > ? AND geo = ? )
2619 OR ( workhrs < ? OR geo = ? ) ) )";
2620 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2622 =head3 Algebraic inconsistency, for historical reasons
2624 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2625 operator goes C<outside> of the nested structure; whereas when connecting
2626 several constraints on one column, the C<-and> operator goes
2627 C<inside> the arrayref. Here is an example combining both features :
2630 -and => [a => 1, b => 2],
2631 -or => [c => 3, d => 4],
2632 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2637 WHERE ( ( ( a = ? AND b = ? )
2638 OR ( c = ? OR d = ? )
2639 OR ( e LIKE ? AND e LIKE ? ) ) )
2641 This difference in syntax is unfortunate but must be preserved for
2642 historical reasons. So be careful : the two examples below would
2643 seem algebraically equivalent, but they are not
2646 { -like => 'foo%' },
2647 { -like => '%bar' },
2649 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2652 { col => { -like => 'foo%' } },
2653 { col => { -like => '%bar' } },
2655 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2658 =head2 Literal SQL and value type operators
2660 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2661 side" is a column name and the "right side" is a value (normally rendered as
2662 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2663 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2664 alter this behavior. There are several ways of doing so.
2668 This is a virtual operator that signals the string to its right side is an
2669 identifier (a column name) and not a value. For example to compare two
2670 columns you would write:
2673 priority => { '<', 2 },
2674 requestor => { -ident => 'submitter' },
2679 $stmt = "WHERE priority < ? AND requestor = submitter";
2682 If you are maintaining legacy code you may see a different construct as
2683 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2688 This is a virtual operator that signals that the construct to its right side
2689 is a value to be passed to DBI. This is for example necessary when you want
2690 to write a where clause against an array (for RDBMS that support such
2691 datatypes). For example:
2694 array => { -value => [1, 2, 3] }
2699 $stmt = 'WHERE array = ?';
2700 @bind = ([1, 2, 3]);
2702 Note that if you were to simply say:
2708 the result would probably not be what you wanted:
2710 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2715 Finally, sometimes only literal SQL will do. To include a random snippet
2716 of SQL verbatim, you specify it as a scalar reference. Consider this only
2717 as a last resort. Usually there is a better way. For example:
2720 priority => { '<', 2 },
2721 requestor => { -in => \'(SELECT name FROM hitmen)' },
2726 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2729 Note that in this example, you only get one bind parameter back, since
2730 the verbatim SQL is passed as part of the statement.
2734 Never use untrusted input as a literal SQL argument - this is a massive
2735 security risk (there is no way to check literal snippets for SQL
2736 injections and other nastyness). If you need to deal with untrusted input
2737 use literal SQL with placeholders as described next.
2739 =head3 Literal SQL with placeholders and bind values (subqueries)
2741 If the literal SQL to be inserted has placeholders and bind values,
2742 use a reference to an arrayref (yes this is a double reference --
2743 not so common, but perfectly legal Perl). For example, to find a date
2744 in Postgres you can use something like this:
2747 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2752 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2755 Note that you must pass the bind values in the same format as they are returned
2756 by L<where|/where(\%where, $order)>. This means that if you set L</bindtype>
2757 to C<columns>, you must provide the bind values in the
2758 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2759 scalar value; most commonly the column name, but you can use any scalar value
2760 (including references and blessed references), L<SQL::Abstract> will simply
2761 pass it through intact. So if C<bindtype> is set to C<columns> the above
2762 example will look like:
2765 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2768 Literal SQL is especially useful for nesting parenthesized clauses in the
2769 main SQL query. Here is a first example :
2771 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2775 bar => \["IN ($sub_stmt)" => @sub_bind],
2780 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2781 WHERE c2 < ? AND c3 LIKE ?))";
2782 @bind = (1234, 100, "foo%");
2784 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2785 are expressed in the same way. Of course the C<$sub_stmt> and
2786 its associated bind values can be generated through a former call
2789 my ($sub_stmt, @sub_bind)
2790 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2791 c3 => {-like => "foo%"}});
2794 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2797 In the examples above, the subquery was used as an operator on a column;
2798 but the same principle also applies for a clause within the main C<%where>
2799 hash, like an EXISTS subquery :
2801 my ($sub_stmt, @sub_bind)
2802 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2803 my %where = ( -and => [
2805 \["EXISTS ($sub_stmt)" => @sub_bind],
2810 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2811 WHERE c1 = ? AND c2 > t0.c0))";
2815 Observe that the condition on C<c2> in the subquery refers to
2816 column C<t0.c0> of the main query : this is I<not> a bind
2817 value, so we have to express it through a scalar ref.
2818 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2819 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2820 what we wanted here.
2822 Finally, here is an example where a subquery is used
2823 for expressing unary negation:
2825 my ($sub_stmt, @sub_bind)
2826 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2827 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2829 lname => {like => '%son%'},
2830 \["NOT ($sub_stmt)" => @sub_bind],
2835 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2836 @bind = ('%son%', 10, 20)
2838 =head3 Deprecated usage of Literal SQL
2840 Below are some examples of archaic use of literal SQL. It is shown only as
2841 reference for those who deal with legacy code. Each example has a much
2842 better, cleaner and safer alternative that users should opt for in new code.
2848 my %where = ( requestor => \'IS NOT NULL' )
2850 $stmt = "WHERE requestor IS NOT NULL"
2852 This used to be the way of generating NULL comparisons, before the handling
2853 of C<undef> got formalized. For new code please use the superior syntax as
2854 described in L</Tests for NULL values>.
2858 my %where = ( requestor => \'= submitter' )
2860 $stmt = "WHERE requestor = submitter"
2862 This used to be the only way to compare columns. Use the superior L</-ident>
2863 method for all new code. For example an identifier declared in such a way
2864 will be properly quoted if L</quote_char> is properly set, while the legacy
2865 form will remain as supplied.
2869 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2871 $stmt = "WHERE completed > ? AND is_ready"
2872 @bind = ('2012-12-21')
2874 Using an empty string literal used to be the only way to express a boolean.
2875 For all new code please use the much more readable
2876 L<-bool|/Unary operators: bool> operator.
2882 These pages could go on for a while, since the nesting of the data
2883 structures this module can handle are pretty much unlimited (the
2884 module implements the C<WHERE> expansion as a recursive function
2885 internally). Your best bet is to "play around" with the module a
2886 little to see how the data structures behave, and choose the best
2887 format for your data based on that.
2889 And of course, all the values above will probably be replaced with
2890 variables gotten from forms or the command line. After all, if you
2891 knew everything ahead of time, you wouldn't have to worry about
2892 dynamically-generating SQL and could just hardwire it into your
2895 =head1 ORDER BY CLAUSES
2897 Some functions take an order by clause. This can either be a scalar (just a
2898 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2899 or an array of either of the two previous forms. Examples:
2901 Given | Will Generate
2902 ----------------------------------------------------------
2904 \'colA DESC' | ORDER BY colA DESC
2906 'colA' | ORDER BY colA
2908 [qw/colA colB/] | ORDER BY colA, colB
2910 {-asc => 'colA'} | ORDER BY colA ASC
2912 {-desc => 'colB'} | ORDER BY colB DESC
2914 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2916 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2919 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2920 { -desc => [qw/colB/], | colC ASC, colD ASC
2921 { -asc => [qw/colC colD/],|
2923 ===========================================================
2927 =head1 SPECIAL OPERATORS
2929 my $sqlmaker = SQL::Abstract->new(special_ops => [
2933 my ($self, $field, $op, $arg) = @_;
2939 handler => 'method_name',
2943 A "special operator" is a SQL syntactic clause that can be
2944 applied to a field, instead of a usual binary operator.
2947 WHERE field IN (?, ?, ?)
2948 WHERE field BETWEEN ? AND ?
2949 WHERE MATCH(field) AGAINST (?, ?)
2951 Special operators IN and BETWEEN are fairly standard and therefore
2952 are builtin within C<SQL::Abstract> (as the overridable methods
2953 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2954 like the MATCH .. AGAINST example above which is specific to MySQL,
2955 you can write your own operator handlers - supply a C<special_ops>
2956 argument to the C<new> method. That argument takes an arrayref of
2957 operator definitions; each operator definition is a hashref with two
2964 the regular expression to match the operator
2968 Either a coderef or a plain scalar method name. In both cases
2969 the expected return is C<< ($sql, @bind) >>.
2971 When supplied with a method name, it is simply called on the
2972 L<SQL::Abstract> object as:
2974 $self->$method_name ($field, $op, $arg)
2978 $field is the LHS of the operator
2979 $op is the part that matched the handler regex
2982 When supplied with a coderef, it is called as:
2984 $coderef->($self, $field, $op, $arg)
2989 For example, here is an implementation
2990 of the MATCH .. AGAINST syntax for MySQL
2992 my $sqlmaker = SQL::Abstract->new(special_ops => [
2994 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2995 {regex => qr/^match$/i,
2997 my ($self, $field, $op, $arg) = @_;
2998 $arg = [$arg] if not ref $arg;
2999 my $label = $self->_quote($field);
3000 my ($placeholder) = $self->_convert('?');
3001 my $placeholders = join ", ", (($placeholder) x @$arg);
3002 my $sql = $self->_sqlcase('match') . " ($label) "
3003 . $self->_sqlcase('against') . " ($placeholders) ";
3004 my @bind = $self->_bindtype($field, @$arg);
3005 return ($sql, @bind);
3012 =head1 UNARY OPERATORS
3014 my $sqlmaker = SQL::Abstract->new(unary_ops => [
3018 my ($self, $op, $arg) = @_;
3024 handler => 'method_name',
3028 A "unary operator" is a SQL syntactic clause that can be
3029 applied to a field - the operator goes before the field
3031 You can write your own operator handlers - supply a C<unary_ops>
3032 argument to the C<new> method. That argument takes an arrayref of
3033 operator definitions; each operator definition is a hashref with two
3040 the regular expression to match the operator
3044 Either a coderef or a plain scalar method name. In both cases
3045 the expected return is C<< $sql >>.
3047 When supplied with a method name, it is simply called on the
3048 L<SQL::Abstract> object as:
3050 $self->$method_name ($op, $arg)
3054 $op is the part that matched the handler regex
3055 $arg is the RHS or argument of the operator
3057 When supplied with a coderef, it is called as:
3059 $coderef->($self, $op, $arg)
3067 Thanks to some benchmarking by Mark Stosberg, it turns out that
3068 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
3069 I must admit this wasn't an intentional design issue, but it's a
3070 byproduct of the fact that you get to control your C<DBI> handles
3073 To maximize performance, use a code snippet like the following:
3075 # prepare a statement handle using the first row
3076 # and then reuse it for the rest of the rows
3078 for my $href (@array_of_hashrefs) {
3079 $stmt ||= $sql->insert('table', $href);
3080 $sth ||= $dbh->prepare($stmt);
3081 $sth->execute($sql->values($href));
3084 The reason this works is because the keys in your C<$href> are sorted
3085 internally by B<SQL::Abstract>. Thus, as long as your data retains
3086 the same structure, you only have to generate the SQL the first time
3087 around. On subsequent queries, simply use the C<values> function provided
3088 by this module to return your values in the correct order.
3090 However this depends on the values having the same type - if, for
3091 example, the values of a where clause may either have values
3092 (resulting in sql of the form C<column = ?> with a single bind
3093 value), or alternatively the values might be C<undef> (resulting in
3094 sql of the form C<column IS NULL> with no bind value) then the
3095 caching technique suggested will not work.
3099 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3100 really like this part (I do, at least). Building up a complex query
3101 can be as simple as the following:
3108 use CGI::FormBuilder;
3111 my $form = CGI::FormBuilder->new(...);
3112 my $sql = SQL::Abstract->new;
3114 if ($form->submitted) {
3115 my $field = $form->field;
3116 my $id = delete $field->{id};
3117 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3120 Of course, you would still have to connect using C<DBI> to run the
3121 query, but the point is that if you make your form look like your
3122 table, the actual query script can be extremely simplistic.
3124 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3125 a fast interface to returning and formatting data. I frequently
3126 use these three modules together to write complex database query
3127 apps in under 50 lines.
3129 =head1 HOW TO CONTRIBUTE
3131 Contributions are always welcome, in all usable forms (we especially
3132 welcome documentation improvements). The delivery methods include git-
3133 or unified-diff formatted patches, GitHub pull requests, or plain bug
3134 reports either via RT or the Mailing list. Contributors are generally
3135 granted full access to the official repository after their first several
3136 patches pass successful review.
3138 This project is maintained in a git repository. The code and related tools are
3139 accessible at the following locations:
3143 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3145 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3147 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3149 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3155 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3156 Great care has been taken to preserve the I<published> behavior
3157 documented in previous versions in the 1.* family; however,
3158 some features that were previously undocumented, or behaved
3159 differently from the documentation, had to be changed in order
3160 to clarify the semantics. Hence, client code that was relying
3161 on some dark areas of C<SQL::Abstract> v1.*
3162 B<might behave differently> in v1.50.
3164 The main changes are :
3170 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3174 support for the { operator => \"..." } construct (to embed literal SQL)
3178 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3182 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3186 defensive programming : check arguments
3190 fixed bug with global logic, which was previously implemented
3191 through global variables yielding side-effects. Prior versions would
3192 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3193 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3194 Now this is interpreted
3195 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3200 fixed semantics of _bindtype on array args
3204 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3205 we just avoid shifting arrays within that tree.
3209 dropped the C<_modlogic> function
3213 =head1 ACKNOWLEDGEMENTS
3215 There are a number of individuals that have really helped out with
3216 this module. Unfortunately, most of them submitted bugs via CPAN
3217 so I have no idea who they are! But the people I do know are:
3219 Ash Berlin (order_by hash term support)
3220 Matt Trout (DBIx::Class support)
3221 Mark Stosberg (benchmarking)
3222 Chas Owens (initial "IN" operator support)
3223 Philip Collins (per-field SQL functions)
3224 Eric Kolve (hashref "AND" support)
3225 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3226 Dan Kubb (support for "quote_char" and "name_sep")
3227 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3228 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3229 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3230 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3231 Oliver Charles (support for "RETURNING" after "INSERT")
3237 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3241 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3243 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3245 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3246 While not an official support venue, C<DBIx::Class> makes heavy use of
3247 C<SQL::Abstract>, and as such list members there are very familiar with
3248 how to create queries.
3252 This module is free software; you may copy this under the same
3253 terms as perl itself (either the GNU General Public License or
3254 the Artistic License)