1 package SQL::Abstract; # see doc at end of file
9 #======================================================================
11 #======================================================================
13 our $VERSION = '1.78';
15 # This would confuse some packagers
16 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
20 # special operators (-in, -between). May be extended/overridden by user.
21 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
22 my @BUILTIN_SPECIAL_OPS = (
23 {regex => qr/^ (?: not \s )? between $/ix, handler => '_where_field_BETWEEN'},
24 {regex => qr/^ (?: not \s )? in $/ix, handler => '_where_field_IN'},
25 {regex => qr/^ ident $/ix, handler => '_where_op_IDENT'},
26 {regex => qr/^ value $/ix, handler => '_where_op_VALUE'},
27 {regex => qr/^ is (?: \s+ not )? $/ix, handler => '_where_field_IS'},
30 # unaryish operators - key maps to handler
31 my @BUILTIN_UNARY_OPS = (
32 # the digits are backcompat stuff
33 { regex => qr/^ and (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
34 { regex => qr/^ or (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
35 { regex => qr/^ nest (?: [_\s]? \d+ )? $/xi, handler => '_where_op_NEST' },
36 { regex => qr/^ (?: not \s )? bool $/xi, handler => '_where_op_BOOL' },
37 { regex => qr/^ ident $/xi, handler => '_where_op_IDENT' },
38 { regex => qr/^ value $/xi, handler => '_where_op_VALUE' },
41 #======================================================================
42 # DEBUGGING AND ERROR REPORTING
43 #======================================================================
46 return unless $_[0]->{debug}; shift; # a little faster
47 my $func = (caller(1))[3];
48 warn "[$func] ", @_, "\n";
52 my($func) = (caller(1))[3];
53 Carp::carp "[$func] Warning: ", @_;
57 my($func) = (caller(1))[3];
58 Carp::croak "[$func] Fatal: ", @_;
62 #======================================================================
64 #======================================================================
68 my $class = ref($self) || $self;
69 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
71 # choose our case by keeping an option around
72 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
74 # default logic for interpreting arrayrefs
75 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
77 # how to return bind vars
78 $opt{bindtype} ||= 'normal';
80 # default comparison is "=", but can be overridden
83 # try to recognize which are the 'equality' and 'inequality' ops
84 # (temporary quickfix (in 2007), should go through a more seasoned API)
85 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
86 $opt{inequality_op} = qr/^( != | <> )$/ix;
88 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
89 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
92 $opt{sqltrue} ||= '1=1';
93 $opt{sqlfalse} ||= '0=1';
96 $opt{special_ops} ||= [];
97 # regexes are applied in order, thus push after user-defines
98 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
101 $opt{unary_ops} ||= [];
102 push @{$opt{unary_ops}}, @BUILTIN_UNARY_OPS;
104 # rudimentary sanity-check for user supplied bits treated as functions/operators
105 # If a purported function matches this regular expression, an exception is thrown.
106 # Literal SQL is *NOT* subject to this check, only functions (and column names
107 # when quoting is not in effect)
110 # need to guard against ()'s in column names too, but this will break tons of
111 # hacks... ideas anyone?
112 $opt{injection_guard} ||= qr/
118 return bless \%opt, $class;
122 sub _assert_pass_injection_guard {
123 if ($_[1] =~ $_[0]->{injection_guard}) {
124 my $class = ref $_[0];
125 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
126 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
127 . "{injection_guard} attribute to ${class}->new()"
132 #======================================================================
134 #======================================================================
138 my $table = $self->_table(shift);
139 my $data = shift || return;
142 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
143 my ($sql, @bind) = $self->$method($data);
144 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
146 if ($options->{returning}) {
147 my ($s, @b) = $self->_insert_returning ($options);
152 return wantarray ? ($sql, @bind) : $sql;
155 sub _insert_returning {
156 my ($self, $options) = @_;
158 my $f = $options->{returning};
160 my $fieldlist = $self->_SWITCH_refkind($f, {
161 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
162 SCALAR => sub {$self->_quote($f)},
163 SCALARREF => sub {$$f},
165 return $self->_sqlcase(' returning ') . $fieldlist;
168 sub _insert_HASHREF { # explicit list of fields and then values
169 my ($self, $data) = @_;
171 my @fields = sort keys %$data;
173 my ($sql, @bind) = $self->_insert_values($data);
176 $_ = $self->_quote($_) foreach @fields;
177 $sql = "( ".join(", ", @fields).") ".$sql;
179 return ($sql, @bind);
182 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
183 my ($self, $data) = @_;
185 # no names (arrayref) so can't generate bindtype
186 $self->{bindtype} ne 'columns'
187 or belch "can't do 'columns' bindtype when called with arrayref";
189 # fold the list of values into a hash of column name - value pairs
190 # (where the column names are artificially generated, and their
191 # lexicographical ordering keep the ordering of the original list)
192 my $i = "a"; # incremented values will be in lexicographical order
193 my $data_in_hash = { map { ($i++ => $_) } @$data };
195 return $self->_insert_values($data_in_hash);
198 sub _insert_ARRAYREFREF { # literal SQL with bind
199 my ($self, $data) = @_;
201 my ($sql, @bind) = @${$data};
202 $self->_assert_bindval_matches_bindtype(@bind);
204 return ($sql, @bind);
208 sub _insert_SCALARREF { # literal SQL without bind
209 my ($self, $data) = @_;
215 my ($self, $data) = @_;
217 my (@values, @all_bind);
218 foreach my $column (sort keys %$data) {
219 my $v = $data->{$column};
221 $self->_SWITCH_refkind($v, {
224 if ($self->{array_datatypes}) { # if array datatype are activated
226 push @all_bind, $self->_bindtype($column, $v);
228 else { # else literal SQL with bind
229 my ($sql, @bind) = @$v;
230 $self->_assert_bindval_matches_bindtype(@bind);
232 push @all_bind, @bind;
236 ARRAYREFREF => sub { # literal SQL with bind
237 my ($sql, @bind) = @${$v};
238 $self->_assert_bindval_matches_bindtype(@bind);
240 push @all_bind, @bind;
243 # THINK : anything useful to do with a HASHREF ?
244 HASHREF => sub { # (nothing, but old SQLA passed it through)
245 #TODO in SQLA >= 2.0 it will die instead
246 belch "HASH ref as bind value in insert is not supported";
248 push @all_bind, $self->_bindtype($column, $v);
251 SCALARREF => sub { # literal SQL without bind
255 SCALAR_or_UNDEF => sub {
257 push @all_bind, $self->_bindtype($column, $v);
264 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
265 return ($sql, @all_bind);
270 #======================================================================
272 #======================================================================
277 my $table = $self->_table(shift);
278 my $data = shift || return;
281 # first build the 'SET' part of the sql statement
282 my (@set, @all_bind);
283 puke "Unsupported data type specified to \$sql->update"
284 unless ref $data eq 'HASH';
286 for my $k (sort keys %$data) {
289 my $label = $self->_quote($k);
291 $self->_SWITCH_refkind($v, {
293 if ($self->{array_datatypes}) { # array datatype
294 push @set, "$label = ?";
295 push @all_bind, $self->_bindtype($k, $v);
297 else { # literal SQL with bind
298 my ($sql, @bind) = @$v;
299 $self->_assert_bindval_matches_bindtype(@bind);
300 push @set, "$label = $sql";
301 push @all_bind, @bind;
304 ARRAYREFREF => sub { # literal SQL with bind
305 my ($sql, @bind) = @${$v};
306 $self->_assert_bindval_matches_bindtype(@bind);
307 push @set, "$label = $sql";
308 push @all_bind, @bind;
310 SCALARREF => sub { # literal SQL without bind
311 push @set, "$label = $$v";
314 my ($op, $arg, @rest) = %$v;
316 puke 'Operator calls in update must be in the form { -op => $arg }'
317 if (@rest or not $op =~ /^\-(.+)/);
319 local $self->{_nested_func_lhs} = $k;
320 my ($sql, @bind) = $self->_where_unary_op ($1, $arg);
322 push @set, "$label = $sql";
323 push @all_bind, @bind;
325 SCALAR_or_UNDEF => sub {
326 push @set, "$label = ?";
327 push @all_bind, $self->_bindtype($k, $v);
333 my $sql = $self->_sqlcase('update') . " $table " . $self->_sqlcase('set ')
337 my($where_sql, @where_bind) = $self->where($where);
339 push @all_bind, @where_bind;
342 return wantarray ? ($sql, @all_bind) : $sql;
348 #======================================================================
350 #======================================================================
355 my $table = $self->_table(shift);
356 my $fields = shift || '*';
360 my($where_sql, @bind) = $self->where($where, $order);
362 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
364 my $sql = join(' ', $self->_sqlcase('select'), $f,
365 $self->_sqlcase('from'), $table)
368 return wantarray ? ($sql, @bind) : $sql;
371 #======================================================================
373 #======================================================================
378 my $table = $self->_table(shift);
382 my($where_sql, @bind) = $self->where($where);
383 my $sql = $self->_sqlcase('delete from') . " $table" . $where_sql;
385 return wantarray ? ($sql, @bind) : $sql;
389 #======================================================================
391 #======================================================================
395 # Finally, a separate routine just to handle WHERE clauses
397 my ($self, $where, $order) = @_;
400 my ($sql, @bind) = $self->_recurse_where($where);
401 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
405 $sql .= $self->_order_by($order);
408 return wantarray ? ($sql, @bind) : $sql;
413 my ($self, $where, $logic) = @_;
415 # dispatch on appropriate method according to refkind of $where
416 my $method = $self->_METHOD_FOR_refkind("_where", $where);
418 my ($sql, @bind) = $self->$method($where, $logic);
420 # DBIx::Class directly calls _recurse_where in scalar context, so
421 # we must implement it, even if not in the official API
422 return wantarray ? ($sql, @bind) : $sql;
427 #======================================================================
428 # WHERE: top-level ARRAYREF
429 #======================================================================
432 sub _where_ARRAYREF {
433 my ($self, $where, $logic) = @_;
435 $logic = uc($logic || $self->{logic});
436 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
438 my @clauses = @$where;
440 my (@sql_clauses, @all_bind);
441 # need to use while() so can shift() for pairs
442 while (my $el = shift @clauses) {
444 # switch according to kind of $el and get corresponding ($sql, @bind)
445 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
447 # skip empty elements, otherwise get invalid trailing AND stuff
448 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
452 $self->_assert_bindval_matches_bindtype(@b);
456 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
458 SCALARREF => sub { ($$el); },
460 SCALAR => sub {# top-level arrayref with scalars, recurse in pairs
461 $self->_recurse_where({$el => shift(@clauses)})},
463 UNDEF => sub {puke "not supported : UNDEF in arrayref" },
467 push @sql_clauses, $sql;
468 push @all_bind, @bind;
472 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
475 #======================================================================
476 # WHERE: top-level ARRAYREFREF
477 #======================================================================
479 sub _where_ARRAYREFREF {
480 my ($self, $where) = @_;
481 my ($sql, @bind) = @$$where;
482 $self->_assert_bindval_matches_bindtype(@bind);
483 return ($sql, @bind);
486 #======================================================================
487 # WHERE: top-level HASHREF
488 #======================================================================
491 my ($self, $where) = @_;
492 my (@sql_clauses, @all_bind);
494 for my $k (sort keys %$where) {
495 my $v = $where->{$k};
497 # ($k => $v) is either a special unary op or a regular hashpair
498 my ($sql, @bind) = do {
500 # put the operator in canonical form
502 $op = substr $op, 1; # remove initial dash
503 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
504 $op =~ s/\s+/ /g; # compress whitespace
506 # so that -not_foo works correctly
507 $op =~ s/^not_/NOT /i;
509 $self->_debug("Unary OP(-$op) within hashref, recursing...");
510 my ($s, @b) = $self->_where_unary_op ($op, $v);
512 # top level vs nested
513 # we assume that handled unary ops will take care of their ()s
515 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
517 defined($self->{_nested_func_lhs}) && ($self->{_nested_func_lhs} eq $k)
522 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
523 $self->$method($k, $v);
527 push @sql_clauses, $sql;
528 push @all_bind, @bind;
531 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
534 sub _where_unary_op {
535 my ($self, $op, $rhs) = @_;
537 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
538 my $handler = $op_entry->{handler};
540 if (not ref $handler) {
541 if ($op =~ s/ [_\s]? \d+ $//x ) {
542 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
543 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
545 return $self->$handler ($op, $rhs);
547 elsif (ref $handler eq 'CODE') {
548 return $handler->($self, $op, $rhs);
551 puke "Illegal handler for operator $op - expecting a method name or a coderef";
555 $self->_debug("Generic unary OP: $op - recursing as function");
557 $self->_assert_pass_injection_guard($op);
559 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
561 puke "Illegal use of top-level '$op'"
562 unless $self->{_nested_func_lhs};
565 $self->_convert('?'),
566 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
570 $self->_recurse_where ($rhs)
574 $sql = sprintf ('%s %s',
575 $self->_sqlcase($op),
579 return ($sql, @bind);
582 sub _where_op_ANDOR {
583 my ($self, $op, $v) = @_;
585 $self->_SWITCH_refkind($v, {
587 return $self->_where_ARRAYREF($v, $op);
591 return ( $op =~ /^or/i )
592 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
593 : $self->_where_HASHREF($v);
597 puke "-$op => \\\$scalar makes little sense, use " .
599 ? '[ \$scalar, \%rest_of_conditions ] instead'
600 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
605 puke "-$op => \\[...] makes little sense, use " .
607 ? '[ \[...], \%rest_of_conditions ] instead'
608 : '-and => [ \[...], \%rest_of_conditions ] instead'
612 SCALAR => sub { # permissively interpreted as SQL
613 puke "-$op => \$value makes little sense, use -bool => \$value instead";
617 puke "-$op => undef not supported";
623 my ($self, $op, $v) = @_;
625 $self->_SWITCH_refkind($v, {
627 SCALAR => sub { # permissively interpreted as SQL
628 belch "literal SQL should be -nest => \\'scalar' "
629 . "instead of -nest => 'scalar' ";
634 puke "-$op => undef not supported";
638 $self->_recurse_where ($v);
646 my ($self, $op, $v) = @_;
648 my ($s, @b) = $self->_SWITCH_refkind($v, {
649 SCALAR => sub { # interpreted as SQL column
650 $self->_convert($self->_quote($v));
654 puke "-$op => undef not supported";
658 $self->_recurse_where ($v);
662 $s = "(NOT $s)" if $op =~ /^not/i;
667 sub _where_op_IDENT {
669 my ($op, $rhs) = splice @_, -2;
671 puke "-$op takes a single scalar argument (a quotable identifier)";
674 # in case we are called as a top level special op (no '=')
677 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
685 sub _where_op_VALUE {
687 my ($op, $rhs) = splice @_, -2;
689 # in case we are called as a top level special op (no '=')
694 ($lhs || $self->{_nested_func_lhs}),
701 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
705 $self->_convert('?'),
711 sub _where_hashpair_ARRAYREF {
712 my ($self, $k, $v) = @_;
715 my @v = @$v; # need copy because of shift below
716 $self->_debug("ARRAY($k) means distribute over elements");
718 # put apart first element if it is an operator (-and, -or)
720 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
724 my @distributed = map { {$k => $_} } @v;
727 $self->_debug("OP($op) reinjected into the distributed array");
728 unshift @distributed, $op;
731 my $logic = $op ? substr($op, 1) : '';
733 return $self->_recurse_where(\@distributed, $logic);
736 $self->_debug("empty ARRAY($k) means 0=1");
737 return ($self->{sqlfalse});
741 sub _where_hashpair_HASHREF {
742 my ($self, $k, $v, $logic) = @_;
745 local $self->{_nested_func_lhs} = $self->{_nested_func_lhs};
747 my ($all_sql, @all_bind);
749 for my $orig_op (sort keys %$v) {
750 my $val = $v->{$orig_op};
752 # put the operator in canonical form
755 # FIXME - we need to phase out dash-less ops
756 $op =~ s/^-//; # remove possible initial dash
757 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
758 $op =~ s/\s+/ /g; # compress whitespace
760 $self->_assert_pass_injection_guard($op);
763 $op =~ s/^is_not/IS NOT/i;
765 # so that -not_foo works correctly
766 $op =~ s/^not_/NOT /i;
770 # CASE: col-value logic modifiers
771 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
772 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
774 # CASE: special operators like -in or -between
775 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
776 my $handler = $special_op->{handler};
778 puke "No handler supplied for special operator $orig_op";
780 elsif (not ref $handler) {
781 ($sql, @bind) = $self->$handler ($k, $op, $val);
783 elsif (ref $handler eq 'CODE') {
784 ($sql, @bind) = $handler->($self, $k, $op, $val);
787 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
791 $self->_SWITCH_refkind($val, {
793 ARRAYREF => sub { # CASE: col => {op => \@vals}
794 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
797 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
798 my ($sub_sql, @sub_bind) = @$$val;
799 $self->_assert_bindval_matches_bindtype(@sub_bind);
800 $sql = join ' ', $self->_convert($self->_quote($k)),
801 $self->_sqlcase($op),
806 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
808 $op =~ /^not$/i ? 'is not' # legacy
809 : $op =~ $self->{equality_op} ? 'is'
810 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
811 : $op =~ $self->{inequality_op} ? 'is not'
812 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
813 : puke "unexpected operator '$orig_op' with undef operand";
815 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
818 FALLBACK => sub { # CASE: col => {op/func => $stuff}
820 # retain for proper column type bind
821 $self->{_nested_func_lhs} ||= $k;
823 ($sql, @bind) = $self->_where_unary_op ($op, $val);
826 $self->_convert($self->_quote($k)),
827 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
833 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
834 push @all_bind, @bind;
836 return ($all_sql, @all_bind);
839 sub _where_field_IS {
840 my ($self, $k, $op, $v) = @_;
842 my ($s) = $self->_SWITCH_refkind($v, {
845 $self->_convert($self->_quote($k)),
846 map { $self->_sqlcase($_)} ($op, 'null')
849 puke "$op can only take undef as argument";
856 sub _where_field_op_ARRAYREF {
857 my ($self, $k, $op, $vals) = @_;
859 my @vals = @$vals; #always work on a copy
862 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
864 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
867 # see if the first element is an -and/-or op
869 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
874 # a long standing API wart - an attempt to change this behavior during
875 # the 1.50 series failed *spectacularly*. Warn instead and leave the
880 (!$logic or $logic eq 'OR')
882 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
885 belch "A multi-element arrayref as an argument to the inequality op '$o' "
886 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
887 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
891 # distribute $op over each remaining member of @vals, append logic if exists
892 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
896 # try to DWIM on equality operators
898 $op =~ $self->{equality_op} ? $self->{sqlfalse}
899 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
900 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
901 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
902 : puke "operator '$op' applied on an empty array (field '$k')";
907 sub _where_hashpair_SCALARREF {
908 my ($self, $k, $v) = @_;
909 $self->_debug("SCALAR($k) means literal SQL: $$v");
910 my $sql = $self->_quote($k) . " " . $$v;
914 # literal SQL with bind
915 sub _where_hashpair_ARRAYREFREF {
916 my ($self, $k, $v) = @_;
917 $self->_debug("REF($k) means literal SQL: @${$v}");
918 my ($sql, @bind) = @$$v;
919 $self->_assert_bindval_matches_bindtype(@bind);
920 $sql = $self->_quote($k) . " " . $sql;
921 return ($sql, @bind );
924 # literal SQL without bind
925 sub _where_hashpair_SCALAR {
926 my ($self, $k, $v) = @_;
927 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
928 my $sql = join ' ', $self->_convert($self->_quote($k)),
929 $self->_sqlcase($self->{cmp}),
930 $self->_convert('?');
931 my @bind = $self->_bindtype($k, $v);
932 return ( $sql, @bind);
936 sub _where_hashpair_UNDEF {
937 my ($self, $k, $v) = @_;
938 $self->_debug("UNDEF($k) means IS NULL");
939 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
943 #======================================================================
944 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
945 #======================================================================
948 sub _where_SCALARREF {
949 my ($self, $where) = @_;
952 $self->_debug("SCALAR(*top) means literal SQL: $$where");
958 my ($self, $where) = @_;
961 $self->_debug("NOREF(*top) means literal SQL: $where");
972 #======================================================================
973 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
974 #======================================================================
977 sub _where_field_BETWEEN {
978 my ($self, $k, $op, $vals) = @_;
980 my ($label, $and, $placeholder);
981 $label = $self->_convert($self->_quote($k));
982 $and = ' ' . $self->_sqlcase('and') . ' ';
983 $placeholder = $self->_convert('?');
984 $op = $self->_sqlcase($op);
986 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
988 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
990 my ($s, @b) = @$$vals;
991 $self->_assert_bindval_matches_bindtype(@b);
998 puke $invalid_args if @$vals != 2;
1000 my (@all_sql, @all_bind);
1001 foreach my $val (@$vals) {
1002 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1004 return ($placeholder, $self->_bindtype($k, $val) );
1009 ARRAYREFREF => sub {
1010 my ($sql, @bind) = @$$val;
1011 $self->_assert_bindval_matches_bindtype(@bind);
1012 return ($sql, @bind);
1015 my ($func, $arg, @rest) = %$val;
1016 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1017 if (@rest or $func !~ /^ \- (.+)/x);
1018 local $self->{_nested_func_lhs} = $k;
1019 $self->_where_unary_op ($1 => $arg);
1025 push @all_sql, $sql;
1026 push @all_bind, @bind;
1030 (join $and, @all_sql),
1039 my $sql = "( $label $op $clause )";
1040 return ($sql, @bind)
1044 sub _where_field_IN {
1045 my ($self, $k, $op, $vals) = @_;
1047 # backwards compatibility : if scalar, force into an arrayref
1048 $vals = [$vals] if defined $vals && ! ref $vals;
1050 my ($label) = $self->_convert($self->_quote($k));
1051 my ($placeholder) = $self->_convert('?');
1052 $op = $self->_sqlcase($op);
1054 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1055 ARRAYREF => sub { # list of choices
1056 if (@$vals) { # nonempty list
1057 my (@all_sql, @all_bind);
1059 for my $val (@$vals) {
1060 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1062 return ($placeholder, $val);
1067 ARRAYREFREF => sub {
1068 my ($sql, @bind) = @$$val;
1069 $self->_assert_bindval_matches_bindtype(@bind);
1070 return ($sql, @bind);
1073 my ($func, $arg, @rest) = %$val;
1074 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1075 if (@rest or $func !~ /^ \- (.+)/x);
1076 local $self->{_nested_func_lhs} = $k;
1077 $self->_where_unary_op ($1 => $arg);
1081 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1082 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1083 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1084 . 'will emit the logically correct SQL instead of raising this exception)'
1088 push @all_sql, $sql;
1089 push @all_bind, @bind;
1093 sprintf ('%s %s ( %s )',
1096 join (', ', @all_sql)
1098 $self->_bindtype($k, @all_bind),
1101 else { # empty list : some databases won't understand "IN ()", so DWIM
1102 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1107 SCALARREF => sub { # literal SQL
1108 my $sql = $self->_open_outer_paren ($$vals);
1109 return ("$label $op ( $sql )");
1111 ARRAYREFREF => sub { # literal SQL with bind
1112 my ($sql, @bind) = @$$vals;
1113 $self->_assert_bindval_matches_bindtype(@bind);
1114 $sql = $self->_open_outer_paren ($sql);
1115 return ("$label $op ( $sql )", @bind);
1119 puke "Argument passed to the '$op' operator can not be undefined";
1123 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1127 return ($sql, @bind);
1130 # Some databases (SQLite) treat col IN (1, 2) different from
1131 # col IN ( (1, 2) ). Use this to strip all outer parens while
1132 # adding them back in the corresponding method
1133 sub _open_outer_paren {
1134 my ($self, $sql) = @_;
1135 $sql = $1 while $sql =~ /^ \s* \( (.*) \) \s* $/xs;
1140 #======================================================================
1142 #======================================================================
1145 my ($self, $arg) = @_;
1148 for my $c ($self->_order_by_chunks ($arg) ) {
1149 $self->_SWITCH_refkind ($c, {
1150 SCALAR => sub { push @sql, $c },
1151 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1157 $self->_sqlcase(' order by'),
1163 return wantarray ? ($sql, @bind) : $sql;
1166 sub _order_by_chunks {
1167 my ($self, $arg) = @_;
1169 return $self->_SWITCH_refkind($arg, {
1172 map { $self->_order_by_chunks ($_ ) } @$arg;
1175 ARRAYREFREF => sub {
1176 my ($s, @b) = @$$arg;
1177 $self->_assert_bindval_matches_bindtype(@b);
1181 SCALAR => sub {$self->_quote($arg)},
1183 UNDEF => sub {return () },
1185 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1188 # get first pair in hash
1189 my ($key, $val, @rest) = %$arg;
1191 return () unless $key;
1193 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1194 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1200 for my $c ($self->_order_by_chunks ($val)) {
1203 $self->_SWITCH_refkind ($c, {
1208 ($sql, @bind) = @$c;
1212 $sql = $sql . ' ' . $self->_sqlcase($direction);
1214 push @ret, [ $sql, @bind];
1223 #======================================================================
1224 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1225 #======================================================================
1230 $self->_SWITCH_refkind($from, {
1231 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1232 SCALAR => sub {$self->_quote($from)},
1233 SCALARREF => sub {$$from},
1238 #======================================================================
1240 #======================================================================
1242 # highly optimized, as it's called way too often
1244 # my ($self, $label) = @_;
1246 return '' unless defined $_[1];
1247 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1249 unless ($_[0]->{quote_char}) {
1250 $_[0]->_assert_pass_injection_guard($_[1]);
1254 my $qref = ref $_[0]->{quote_char};
1257 ($l, $r) = ( $_[0]->{quote_char}, $_[0]->{quote_char} );
1259 elsif ($qref eq 'ARRAY') {
1260 ($l, $r) = @{$_[0]->{quote_char}};
1263 puke "Unsupported quote_char format: $_[0]->{quote_char}";
1265 my $esc = $_[0]->{escape_char} || $r;
1267 # parts containing * are naturally unquoted
1268 return join( $_[0]->{name_sep}||'', map
1269 { $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } }
1270 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1275 # Conversion, if applicable
1277 #my ($self, $arg) = @_;
1278 if ($_[0]->{convert}) {
1279 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1286 #my ($self, $col, @vals) = @_;
1287 # called often - tighten code
1288 return $_[0]->{bindtype} eq 'columns'
1289 ? map {[$_[1], $_]} @_[2 .. $#_]
1294 # Dies if any element of @bind is not in [colname => value] format
1295 # if bindtype is 'columns'.
1296 sub _assert_bindval_matches_bindtype {
1297 # my ($self, @bind) = @_;
1299 if ($self->{bindtype} eq 'columns') {
1301 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1302 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1308 sub _join_sql_clauses {
1309 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1311 if (@$clauses_aref > 1) {
1312 my $join = " " . $self->_sqlcase($logic) . " ";
1313 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1314 return ($sql, @$bind_aref);
1316 elsif (@$clauses_aref) {
1317 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1320 return (); # if no SQL, ignore @$bind_aref
1325 # Fix SQL case, if so requested
1327 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1328 # don't touch the argument ... crooked logic, but let's not change it!
1329 return $_[0]->{case} ? $_[1] : uc($_[1]);
1333 #======================================================================
1334 # DISPATCHING FROM REFKIND
1335 #======================================================================
1338 my ($self, $data) = @_;
1340 return 'UNDEF' unless defined $data;
1342 # blessed objects are treated like scalars
1343 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1345 return 'SCALAR' unless $ref;
1348 while ($ref eq 'REF') {
1350 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1354 return ($ref||'SCALAR') . ('REF' x $n_steps);
1358 my ($self, $data) = @_;
1359 my @try = ($self->_refkind($data));
1360 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1361 push @try, 'FALLBACK';
1365 sub _METHOD_FOR_refkind {
1366 my ($self, $meth_prefix, $data) = @_;
1369 for (@{$self->_try_refkind($data)}) {
1370 $method = $self->can($meth_prefix."_".$_)
1374 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1378 sub _SWITCH_refkind {
1379 my ($self, $data, $dispatch_table) = @_;
1382 for (@{$self->_try_refkind($data)}) {
1383 $coderef = $dispatch_table->{$_}
1387 puke "no dispatch entry for ".$self->_refkind($data)
1396 #======================================================================
1397 # VALUES, GENERATE, AUTOLOAD
1398 #======================================================================
1400 # LDNOTE: original code from nwiger, didn't touch code in that section
1401 # I feel the AUTOLOAD stuff should not be the default, it should
1402 # only be activated on explicit demand by user.
1406 my $data = shift || return;
1407 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1408 unless ref $data eq 'HASH';
1411 foreach my $k ( sort keys %$data ) {
1412 my $v = $data->{$k};
1413 $self->_SWITCH_refkind($v, {
1415 if ($self->{array_datatypes}) { # array datatype
1416 push @all_bind, $self->_bindtype($k, $v);
1418 else { # literal SQL with bind
1419 my ($sql, @bind) = @$v;
1420 $self->_assert_bindval_matches_bindtype(@bind);
1421 push @all_bind, @bind;
1424 ARRAYREFREF => sub { # literal SQL with bind
1425 my ($sql, @bind) = @${$v};
1426 $self->_assert_bindval_matches_bindtype(@bind);
1427 push @all_bind, @bind;
1429 SCALARREF => sub { # literal SQL without bind
1431 SCALAR_or_UNDEF => sub {
1432 push @all_bind, $self->_bindtype($k, $v);
1443 my(@sql, @sqlq, @sqlv);
1447 if ($ref eq 'HASH') {
1448 for my $k (sort keys %$_) {
1451 my $label = $self->_quote($k);
1452 if ($r eq 'ARRAY') {
1453 # literal SQL with bind
1454 my ($sql, @bind) = @$v;
1455 $self->_assert_bindval_matches_bindtype(@bind);
1456 push @sqlq, "$label = $sql";
1458 } elsif ($r eq 'SCALAR') {
1459 # literal SQL without bind
1460 push @sqlq, "$label = $$v";
1462 push @sqlq, "$label = ?";
1463 push @sqlv, $self->_bindtype($k, $v);
1466 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1467 } elsif ($ref eq 'ARRAY') {
1468 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1471 if ($r eq 'ARRAY') { # literal SQL with bind
1472 my ($sql, @bind) = @$v;
1473 $self->_assert_bindval_matches_bindtype(@bind);
1476 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1477 # embedded literal SQL
1484 push @sql, '(' . join(', ', @sqlq) . ')';
1485 } elsif ($ref eq 'SCALAR') {
1489 # strings get case twiddled
1490 push @sql, $self->_sqlcase($_);
1494 my $sql = join ' ', @sql;
1496 # this is pretty tricky
1497 # if ask for an array, return ($stmt, @bind)
1498 # otherwise, s/?/shift @sqlv/ to put it inline
1500 return ($sql, @sqlv);
1502 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1503 ref $d ? $d->[1] : $d/e;
1512 # This allows us to check for a local, then _form, attr
1514 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1515 return $self->generate($name, @_);
1526 SQL::Abstract - Generate SQL from Perl data structures
1532 my $sql = SQL::Abstract->new;
1534 my($stmt, @bind) = $sql->select($source, \@fields, \%where, \@order);
1536 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1538 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1540 my($stmt, @bind) = $sql->delete($table, \%where);
1542 # Then, use these in your DBI statements
1543 my $sth = $dbh->prepare($stmt);
1544 $sth->execute(@bind);
1546 # Just generate the WHERE clause
1547 my($stmt, @bind) = $sql->where(\%where, \@order);
1549 # Return values in the same order, for hashed queries
1550 # See PERFORMANCE section for more details
1551 my @bind = $sql->values(\%fieldvals);
1555 This module was inspired by the excellent L<DBIx::Abstract>.
1556 However, in using that module I found that what I really wanted
1557 to do was generate SQL, but still retain complete control over my
1558 statement handles and use the DBI interface. So, I set out to
1559 create an abstract SQL generation module.
1561 While based on the concepts used by L<DBIx::Abstract>, there are
1562 several important differences, especially when it comes to WHERE
1563 clauses. I have modified the concepts used to make the SQL easier
1564 to generate from Perl data structures and, IMO, more intuitive.
1565 The underlying idea is for this module to do what you mean, based
1566 on the data structures you provide it. The big advantage is that
1567 you don't have to modify your code every time your data changes,
1568 as this module figures it out.
1570 To begin with, an SQL INSERT is as easy as just specifying a hash
1571 of C<key=value> pairs:
1574 name => 'Jimbo Bobson',
1575 phone => '123-456-7890',
1576 address => '42 Sister Lane',
1577 city => 'St. Louis',
1578 state => 'Louisiana',
1581 The SQL can then be generated with this:
1583 my($stmt, @bind) = $sql->insert('people', \%data);
1585 Which would give you something like this:
1587 $stmt = "INSERT INTO people
1588 (address, city, name, phone, state)
1589 VALUES (?, ?, ?, ?, ?)";
1590 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1591 '123-456-7890', 'Louisiana');
1593 These are then used directly in your DBI code:
1595 my $sth = $dbh->prepare($stmt);
1596 $sth->execute(@bind);
1598 =head2 Inserting and Updating Arrays
1600 If your database has array types (like for example Postgres),
1601 activate the special option C<< array_datatypes => 1 >>
1602 when creating the C<SQL::Abstract> object.
1603 Then you may use an arrayref to insert and update database array types:
1605 my $sql = SQL::Abstract->new(array_datatypes => 1);
1607 planets => [qw/Mercury Venus Earth Mars/]
1610 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1614 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1616 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1619 =head2 Inserting and Updating SQL
1621 In order to apply SQL functions to elements of your C<%data> you may
1622 specify a reference to an arrayref for the given hash value. For example,
1623 if you need to execute the Oracle C<to_date> function on a value, you can
1624 say something like this:
1628 date_entered => \["to_date(?,'MM/DD/YYYY')", "03/02/2003"],
1631 The first value in the array is the actual SQL. Any other values are
1632 optional and would be included in the bind values array. This gives
1635 my($stmt, @bind) = $sql->insert('people', \%data);
1637 $stmt = "INSERT INTO people (name, date_entered)
1638 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1639 @bind = ('Bill', '03/02/2003');
1641 An UPDATE is just as easy, all you change is the name of the function:
1643 my($stmt, @bind) = $sql->update('people', \%data);
1645 Notice that your C<%data> isn't touched; the module will generate
1646 the appropriately quirky SQL for you automatically. Usually you'll
1647 want to specify a WHERE clause for your UPDATE, though, which is
1648 where handling C<%where> hashes comes in handy...
1650 =head2 Complex where statements
1652 This module can generate pretty complicated WHERE statements
1653 easily. For example, simple C<key=value> pairs are taken to mean
1654 equality, and if you want to see if a field is within a set
1655 of values, you can use an arrayref. Let's say we wanted to
1656 SELECT some data based on this criteria:
1659 requestor => 'inna',
1660 worker => ['nwiger', 'rcwe', 'sfz'],
1661 status => { '!=', 'completed' }
1664 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1666 The above would give you something like this:
1668 $stmt = "SELECT * FROM tickets WHERE
1669 ( requestor = ? ) AND ( status != ? )
1670 AND ( worker = ? OR worker = ? OR worker = ? )";
1671 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1673 Which you could then use in DBI code like so:
1675 my $sth = $dbh->prepare($stmt);
1676 $sth->execute(@bind);
1682 The functions are simple. There's one for each major SQL operation,
1683 and a constructor you use first. The arguments are specified in a
1684 similar order to each function (table, then fields, then a where
1685 clause) to try and simplify things.
1690 =head2 new(option => 'value')
1692 The C<new()> function takes a list of options and values, and returns
1693 a new B<SQL::Abstract> object which can then be used to generate SQL
1694 through the methods below. The options accepted are:
1700 If set to 'lower', then SQL will be generated in all lowercase. By
1701 default SQL is generated in "textbook" case meaning something like:
1703 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1705 Any setting other than 'lower' is ignored.
1709 This determines what the default comparison operator is. By default
1710 it is C<=>, meaning that a hash like this:
1712 %where = (name => 'nwiger', email => 'nate@wiger.org');
1714 Will generate SQL like this:
1716 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1718 However, you may want loose comparisons by default, so if you set
1719 C<cmp> to C<like> you would get SQL such as:
1721 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1723 You can also override the comparison on an individual basis - see
1724 the huge section on L</"WHERE CLAUSES"> at the bottom.
1726 =item sqltrue, sqlfalse
1728 Expressions for inserting boolean values within SQL statements.
1729 By default these are C<1=1> and C<1=0>. They are used
1730 by the special operators C<-in> and C<-not_in> for generating
1731 correct SQL even when the argument is an empty array (see below).
1735 This determines the default logical operator for multiple WHERE
1736 statements in arrays or hashes. If absent, the default logic is "or"
1737 for arrays, and "and" for hashes. This means that a WHERE
1741 event_date => {'>=', '2/13/99'},
1742 event_date => {'<=', '4/24/03'},
1745 will generate SQL like this:
1747 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1749 This is probably not what you want given this query, though (look
1750 at the dates). To change the "OR" to an "AND", simply specify:
1752 my $sql = SQL::Abstract->new(logic => 'and');
1754 Which will change the above C<WHERE> to:
1756 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1758 The logic can also be changed locally by inserting
1759 a modifier in front of an arrayref :
1761 @where = (-and => [event_date => {'>=', '2/13/99'},
1762 event_date => {'<=', '4/24/03'} ]);
1764 See the L</"WHERE CLAUSES"> section for explanations.
1768 This will automatically convert comparisons using the specified SQL
1769 function for both column and value. This is mostly used with an argument
1770 of C<upper> or C<lower>, so that the SQL will have the effect of
1771 case-insensitive "searches". For example, this:
1773 $sql = SQL::Abstract->new(convert => 'upper');
1774 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1776 Will turn out the following SQL:
1778 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1780 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1781 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1782 not validate this option; it will just pass through what you specify verbatim).
1786 This is a kludge because many databases suck. For example, you can't
1787 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1788 Instead, you have to use C<bind_param()>:
1790 $sth->bind_param(1, 'reg data');
1791 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1793 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1794 which loses track of which field each slot refers to. Fear not.
1796 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1797 Currently, you can specify either C<normal> (default) or C<columns>. If you
1798 specify C<columns>, you will get an array that looks like this:
1800 my $sql = SQL::Abstract->new(bindtype => 'columns');
1801 my($stmt, @bind) = $sql->insert(...);
1804 [ 'column1', 'value1' ],
1805 [ 'column2', 'value2' ],
1806 [ 'column3', 'value3' ],
1809 You can then iterate through this manually, using DBI's C<bind_param()>.
1811 $sth->prepare($stmt);
1814 my($col, $data) = @$_;
1815 if ($col eq 'details' || $col eq 'comments') {
1816 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1817 } elsif ($col eq 'image') {
1818 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1820 $sth->bind_param($i, $data);
1824 $sth->execute; # execute without @bind now
1826 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1827 Basically, the advantage is still that you don't have to care which fields
1828 are or are not included. You could wrap that above C<for> loop in a simple
1829 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1830 get a layer of abstraction over manual SQL specification.
1832 Note that if you set L</bindtype> to C<columns>, the C<\[$sql, @bind]>
1833 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1834 will expect the bind values in this format.
1838 This is the character that a table or column name will be quoted
1839 with. By default this is an empty string, but you could set it to
1840 the character C<`>, to generate SQL like this:
1842 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1844 Alternatively, you can supply an array ref of two items, the first being the left
1845 hand quote character, and the second the right hand quote character. For
1846 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1847 that generates SQL like this:
1849 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1851 Quoting is useful if you have tables or columns names that are reserved
1852 words in your database's SQL dialect.
1856 This is the character that will be used to escape L</quote_char>s appearing
1857 in an identifier before it has been quoted.
1859 The paramter default in case of a single L</quote_char> character is the quote
1862 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1863 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
1864 of the B<opening (left)> L</quote_char> within the identifier are currently left
1865 untouched. The default for opening-closing-style quotes may change in future
1866 versions, thus you are B<strongly encouraged> to specify the escape character
1871 This is the character that separates a table and column name. It is
1872 necessary to specify this when the C<quote_char> option is selected,
1873 so that tables and column names can be individually quoted like this:
1875 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1877 =item injection_guard
1879 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1880 column name specified in a query structure. This is a safety mechanism to avoid
1881 injection attacks when mishandling user input e.g.:
1883 my %condition_as_column_value_pairs = get_values_from_user();
1884 $sqla->select( ... , \%condition_as_column_value_pairs );
1886 If the expression matches an exception is thrown. Note that literal SQL
1887 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1889 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1891 =item array_datatypes
1893 When this option is true, arrayrefs in INSERT or UPDATE are
1894 interpreted as array datatypes and are passed directly
1896 When this option is false, arrayrefs are interpreted
1897 as literal SQL, just like refs to arrayrefs
1898 (but this behavior is for backwards compatibility; when writing
1899 new queries, use the "reference to arrayref" syntax
1905 Takes a reference to a list of "special operators"
1906 to extend the syntax understood by L<SQL::Abstract>.
1907 See section L</"SPECIAL OPERATORS"> for details.
1911 Takes a reference to a list of "unary operators"
1912 to extend the syntax understood by L<SQL::Abstract>.
1913 See section L</"UNARY OPERATORS"> for details.
1919 =head2 insert($table, \@values || \%fieldvals, \%options)
1921 This is the simplest function. You simply give it a table name
1922 and either an arrayref of values or hashref of field/value pairs.
1923 It returns an SQL INSERT statement and a list of bind values.
1924 See the sections on L</"Inserting and Updating Arrays"> and
1925 L</"Inserting and Updating SQL"> for information on how to insert
1926 with those data types.
1928 The optional C<\%options> hash reference may contain additional
1929 options to generate the insert SQL. Currently supported options
1936 Takes either a scalar of raw SQL fields, or an array reference of
1937 field names, and adds on an SQL C<RETURNING> statement at the end.
1938 This allows you to return data generated by the insert statement
1939 (such as row IDs) without performing another C<SELECT> statement.
1940 Note, however, this is not part of the SQL standard and may not
1941 be supported by all database engines.
1945 =head2 update($table, \%fieldvals, \%where)
1947 This takes a table, hashref of field/value pairs, and an optional
1948 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1950 See the sections on L</"Inserting and Updating Arrays"> and
1951 L</"Inserting and Updating SQL"> for information on how to insert
1952 with those data types.
1954 =head2 select($source, $fields, $where, $order)
1956 This returns a SQL SELECT statement and associated list of bind values, as
1957 specified by the arguments :
1963 Specification of the 'FROM' part of the statement.
1964 The argument can be either a plain scalar (interpreted as a table
1965 name, will be quoted), or an arrayref (interpreted as a list
1966 of table names, joined by commas, quoted), or a scalarref
1967 (literal table name, not quoted), or a ref to an arrayref
1968 (list of literal table names, joined by commas, not quoted).
1972 Specification of the list of fields to retrieve from
1974 The argument can be either an arrayref (interpreted as a list
1975 of field names, will be joined by commas and quoted), or a
1976 plain scalar (literal SQL, not quoted).
1977 Please observe that this API is not as flexible as that of
1978 the first argument C<$source>, for backwards compatibility reasons.
1982 Optional argument to specify the WHERE part of the query.
1983 The argument is most often a hashref, but can also be
1984 an arrayref or plain scalar --
1985 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1989 Optional argument to specify the ORDER BY part of the query.
1990 The argument can be a scalar, a hashref or an arrayref
1991 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1997 =head2 delete($table, \%where)
1999 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2000 It returns an SQL DELETE statement and list of bind values.
2002 =head2 where(\%where, \@order)
2004 This is used to generate just the WHERE clause. For example,
2005 if you have an arbitrary data structure and know what the
2006 rest of your SQL is going to look like, but want an easy way
2007 to produce a WHERE clause, use this. It returns an SQL WHERE
2008 clause and list of bind values.
2011 =head2 values(\%data)
2013 This just returns the values from the hash C<%data>, in the same
2014 order that would be returned from any of the other above queries.
2015 Using this allows you to markedly speed up your queries if you
2016 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2018 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2020 Warning: This is an experimental method and subject to change.
2022 This returns arbitrarily generated SQL. It's a really basic shortcut.
2023 It will return two different things, depending on return context:
2025 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2026 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2028 These would return the following:
2030 # First calling form
2031 $stmt = "CREATE TABLE test (?, ?)";
2032 @bind = (field1, field2);
2034 # Second calling form
2035 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2037 Depending on what you're trying to do, it's up to you to choose the correct
2038 format. In this example, the second form is what you would want.
2042 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2046 ALTER SESSION SET nls_date_format = 'MM/YY'
2048 You get the idea. Strings get their case twiddled, but everything
2049 else remains verbatim.
2051 =head1 WHERE CLAUSES
2055 This module uses a variation on the idea from L<DBIx::Abstract>. It
2056 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2057 module is that things in arrays are OR'ed, and things in hashes
2060 The easiest way to explain is to show lots of examples. After
2061 each C<%where> hash shown, it is assumed you used:
2063 my($stmt, @bind) = $sql->where(\%where);
2065 However, note that the C<%where> hash can be used directly in any
2066 of the other functions as well, as described above.
2068 =head2 Key-value pairs
2070 So, let's get started. To begin, a simple hash:
2074 status => 'completed'
2077 Is converted to SQL C<key = val> statements:
2079 $stmt = "WHERE user = ? AND status = ?";
2080 @bind = ('nwiger', 'completed');
2082 One common thing I end up doing is having a list of values that
2083 a field can be in. To do this, simply specify a list inside of
2088 status => ['assigned', 'in-progress', 'pending'];
2091 This simple code will create the following:
2093 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2094 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2096 A field associated to an empty arrayref will be considered a
2097 logical false and will generate 0=1.
2099 =head2 Tests for NULL values
2101 If the value part is C<undef> then this is converted to SQL <IS NULL>
2110 $stmt = "WHERE user = ? AND status IS NULL";
2113 To test if a column IS NOT NULL:
2117 status => { '!=', undef },
2120 =head2 Specific comparison operators
2122 If you want to specify a different type of operator for your comparison,
2123 you can use a hashref for a given column:
2127 status => { '!=', 'completed' }
2130 Which would generate:
2132 $stmt = "WHERE user = ? AND status != ?";
2133 @bind = ('nwiger', 'completed');
2135 To test against multiple values, just enclose the values in an arrayref:
2137 status => { '=', ['assigned', 'in-progress', 'pending'] };
2139 Which would give you:
2141 "WHERE status = ? OR status = ? OR status = ?"
2144 The hashref can also contain multiple pairs, in which case it is expanded
2145 into an C<AND> of its elements:
2149 status => { '!=', 'completed', -not_like => 'pending%' }
2152 # Or more dynamically, like from a form
2153 $where{user} = 'nwiger';
2154 $where{status}{'!='} = 'completed';
2155 $where{status}{'-not_like'} = 'pending%';
2157 # Both generate this
2158 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2159 @bind = ('nwiger', 'completed', 'pending%');
2162 To get an OR instead, you can combine it with the arrayref idea:
2166 priority => [ { '=', 2 }, { '>', 5 } ]
2169 Which would generate:
2171 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2172 @bind = ('2', '5', 'nwiger');
2174 If you want to include literal SQL (with or without bind values), just use a
2175 scalar reference or array reference as the value:
2178 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2179 date_expires => { '<' => \"now()" }
2182 Which would generate:
2184 $stmt = "WHERE date_entered > "to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2185 @bind = ('11/26/2008');
2188 =head2 Logic and nesting operators
2190 In the example above,
2191 there is a subtle trap if you want to say something like
2192 this (notice the C<AND>):
2194 WHERE priority != ? AND priority != ?
2196 Because, in Perl you I<can't> do this:
2198 priority => { '!=', 2, '!=', 1 }
2200 As the second C<!=> key will obliterate the first. The solution
2201 is to use the special C<-modifier> form inside an arrayref:
2203 priority => [ -and => {'!=', 2},
2207 Normally, these would be joined by C<OR>, but the modifier tells it
2208 to use C<AND> instead. (Hint: You can use this in conjunction with the
2209 C<logic> option to C<new()> in order to change the way your queries
2210 work by default.) B<Important:> Note that the C<-modifier> goes
2211 B<INSIDE> the arrayref, as an extra first element. This will
2212 B<NOT> do what you think it might:
2214 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2216 Here is a quick list of equivalencies, since there is some overlap:
2219 status => {'!=', 'completed', 'not like', 'pending%' }
2220 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2223 status => {'=', ['assigned', 'in-progress']}
2224 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2225 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2229 =head2 Special operators : IN, BETWEEN, etc.
2231 You can also use the hashref format to compare a list of fields using the
2232 C<IN> comparison operator, by specifying the list as an arrayref:
2235 status => 'completed',
2236 reportid => { -in => [567, 2335, 2] }
2239 Which would generate:
2241 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2242 @bind = ('completed', '567', '2335', '2');
2244 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2247 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2248 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2249 'sqltrue' (by default : C<1=1>).
2251 In addition to the array you can supply a chunk of literal sql or
2252 literal sql with bind:
2255 customer => { -in => \[
2256 'SELECT cust_id FROM cust WHERE balance > ?',
2259 status => { -in => \'SELECT status_codes FROM states' },
2265 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2266 AND status IN ( SELECT status_codes FROM states )
2270 Finally, if the argument to C<-in> is not a reference, it will be
2271 treated as a single-element array.
2273 Another pair of operators is C<-between> and C<-not_between>,
2274 used with an arrayref of two values:
2278 completion_date => {
2279 -not_between => ['2002-10-01', '2003-02-06']
2285 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2287 Just like with C<-in> all plausible combinations of literal SQL
2291 start0 => { -between => [ 1, 2 ] },
2292 start1 => { -between => \["? AND ?", 1, 2] },
2293 start2 => { -between => \"lower(x) AND upper(y)" },
2294 start3 => { -between => [
2296 \["upper(?)", 'stuff' ],
2303 ( start0 BETWEEN ? AND ? )
2304 AND ( start1 BETWEEN ? AND ? )
2305 AND ( start2 BETWEEN lower(x) AND upper(y) )
2306 AND ( start3 BETWEEN lower(x) AND upper(?) )
2308 @bind = (1, 2, 1, 2, 'stuff');
2311 These are the two builtin "special operators"; but the
2312 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2314 =head2 Unary operators: bool
2316 If you wish to test against boolean columns or functions within your
2317 database you can use the C<-bool> and C<-not_bool> operators. For
2318 example to test the column C<is_user> being true and the column
2319 C<is_enabled> being false you would use:-
2323 -not_bool => 'is_enabled',
2328 WHERE is_user AND NOT is_enabled
2330 If a more complex combination is required, testing more conditions,
2331 then you should use the and/or operators:-
2336 -not_bool => { two=> { -rlike => 'bar' } },
2337 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2348 (NOT ( three = ? OR three > ? ))
2351 =head2 Nested conditions, -and/-or prefixes
2353 So far, we've seen how multiple conditions are joined with a top-level
2354 C<AND>. We can change this by putting the different conditions we want in
2355 hashes and then putting those hashes in an array. For example:
2360 status => { -like => ['pending%', 'dispatched'] },
2364 status => 'unassigned',
2368 This data structure would create the following:
2370 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2371 OR ( user = ? AND status = ? ) )";
2372 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2375 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2376 to change the logic inside :
2382 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2383 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2390 WHERE ( user = ? AND (
2391 ( workhrs > ? AND geo = ? )
2392 OR ( workhrs < ? OR geo = ? )
2395 =head3 Algebraic inconsistency, for historical reasons
2397 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2398 operator goes C<outside> of the nested structure; whereas when connecting
2399 several constraints on one column, the C<-and> operator goes
2400 C<inside> the arrayref. Here is an example combining both features :
2403 -and => [a => 1, b => 2],
2404 -or => [c => 3, d => 4],
2405 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2410 WHERE ( ( ( a = ? AND b = ? )
2411 OR ( c = ? OR d = ? )
2412 OR ( e LIKE ? AND e LIKE ? ) ) )
2414 This difference in syntax is unfortunate but must be preserved for
2415 historical reasons. So be careful : the two examples below would
2416 seem algebraically equivalent, but they are not
2418 {col => [-and => {-like => 'foo%'}, {-like => '%bar'}]}
2419 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2421 [-and => {col => {-like => 'foo%'}, {col => {-like => '%bar'}}]]
2422 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2425 =head2 Literal SQL and value type operators
2427 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2428 side" is a column name and the "right side" is a value (normally rendered as
2429 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2430 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2431 alter this behavior. There are several ways of doing so.
2435 This is a virtual operator that signals the string to its right side is an
2436 identifier (a column name) and not a value. For example to compare two
2437 columns you would write:
2440 priority => { '<', 2 },
2441 requestor => { -ident => 'submitter' },
2446 $stmt = "WHERE priority < ? AND requestor = submitter";
2449 If you are maintaining legacy code you may see a different construct as
2450 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2455 This is a virtual operator that signals that the construct to its right side
2456 is a value to be passed to DBI. This is for example necessary when you want
2457 to write a where clause against an array (for RDBMS that support such
2458 datatypes). For example:
2461 array => { -value => [1, 2, 3] }
2466 $stmt = 'WHERE array = ?';
2467 @bind = ([1, 2, 3]);
2469 Note that if you were to simply say:
2475 the result would probably not be what you wanted:
2477 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2482 Finally, sometimes only literal SQL will do. To include a random snippet
2483 of SQL verbatim, you specify it as a scalar reference. Consider this only
2484 as a last resort. Usually there is a better way. For example:
2487 priority => { '<', 2 },
2488 requestor => { -in => \'(SELECT name FROM hitmen)' },
2493 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2496 Note that in this example, you only get one bind parameter back, since
2497 the verbatim SQL is passed as part of the statement.
2501 Never use untrusted input as a literal SQL argument - this is a massive
2502 security risk (there is no way to check literal snippets for SQL
2503 injections and other nastyness). If you need to deal with untrusted input
2504 use literal SQL with placeholders as described next.
2506 =head3 Literal SQL with placeholders and bind values (subqueries)
2508 If the literal SQL to be inserted has placeholders and bind values,
2509 use a reference to an arrayref (yes this is a double reference --
2510 not so common, but perfectly legal Perl). For example, to find a date
2511 in Postgres you can use something like this:
2514 date_column => \[q/= date '2008-09-30' - ?::integer/, 10/]
2519 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2522 Note that you must pass the bind values in the same format as they are returned
2523 by L</where>. That means that if you set L</bindtype> to C<columns>, you must
2524 provide the bind values in the C<< [ column_meta => value ] >> format, where
2525 C<column_meta> is an opaque scalar value; most commonly the column name, but
2526 you can use any scalar value (including references and blessed references),
2527 L<SQL::Abstract> will simply pass it through intact. So if C<bindtype> is set
2528 to C<columns> the above example will look like:
2531 date_column => \[q/= date '2008-09-30' - ?::integer/, [ dummy => 10 ]/]
2534 Literal SQL is especially useful for nesting parenthesized clauses in the
2535 main SQL query. Here is a first example :
2537 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2541 bar => \["IN ($sub_stmt)" => @sub_bind],
2546 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2547 WHERE c2 < ? AND c3 LIKE ?))";
2548 @bind = (1234, 100, "foo%");
2550 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2551 are expressed in the same way. Of course the C<$sub_stmt> and
2552 its associated bind values can be generated through a former call
2555 my ($sub_stmt, @sub_bind)
2556 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2557 c3 => {-like => "foo%"}});
2560 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2563 In the examples above, the subquery was used as an operator on a column;
2564 but the same principle also applies for a clause within the main C<%where>
2565 hash, like an EXISTS subquery :
2567 my ($sub_stmt, @sub_bind)
2568 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2569 my %where = ( -and => [
2571 \["EXISTS ($sub_stmt)" => @sub_bind],
2576 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2577 WHERE c1 = ? AND c2 > t0.c0))";
2581 Observe that the condition on C<c2> in the subquery refers to
2582 column C<t0.c0> of the main query : this is I<not> a bind
2583 value, so we have to express it through a scalar ref.
2584 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2585 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2586 what we wanted here.
2588 Finally, here is an example where a subquery is used
2589 for expressing unary negation:
2591 my ($sub_stmt, @sub_bind)
2592 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2593 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2595 lname => {like => '%son%'},
2596 \["NOT ($sub_stmt)" => @sub_bind],
2601 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2602 @bind = ('%son%', 10, 20)
2604 =head3 Deprecated usage of Literal SQL
2606 Below are some examples of archaic use of literal SQL. It is shown only as
2607 reference for those who deal with legacy code. Each example has a much
2608 better, cleaner and safer alternative that users should opt for in new code.
2614 my %where = ( requestor => \'IS NOT NULL' )
2616 $stmt = "WHERE requestor IS NOT NULL"
2618 This used to be the way of generating NULL comparisons, before the handling
2619 of C<undef> got formalized. For new code please use the superior syntax as
2620 described in L</Tests for NULL values>.
2624 my %where = ( requestor => \'= submitter' )
2626 $stmt = "WHERE requestor = submitter"
2628 This used to be the only way to compare columns. Use the superior L</-ident>
2629 method for all new code. For example an identifier declared in such a way
2630 will be properly quoted if L</quote_char> is properly set, while the legacy
2631 form will remain as supplied.
2635 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2637 $stmt = "WHERE completed > ? AND is_ready"
2638 @bind = ('2012-12-21')
2640 Using an empty string literal used to be the only way to express a boolean.
2641 For all new code please use the much more readable
2642 L<-bool|/Unary operators: bool> operator.
2648 These pages could go on for a while, since the nesting of the data
2649 structures this module can handle are pretty much unlimited (the
2650 module implements the C<WHERE> expansion as a recursive function
2651 internally). Your best bet is to "play around" with the module a
2652 little to see how the data structures behave, and choose the best
2653 format for your data based on that.
2655 And of course, all the values above will probably be replaced with
2656 variables gotten from forms or the command line. After all, if you
2657 knew everything ahead of time, you wouldn't have to worry about
2658 dynamically-generating SQL and could just hardwire it into your
2661 =head1 ORDER BY CLAUSES
2663 Some functions take an order by clause. This can either be a scalar (just a
2664 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2665 or an array of either of the two previous forms. Examples:
2667 Given | Will Generate
2668 ----------------------------------------------------------
2670 \'colA DESC' | ORDER BY colA DESC
2672 'colA' | ORDER BY colA
2674 [qw/colA colB/] | ORDER BY colA, colB
2676 {-asc => 'colA'} | ORDER BY colA ASC
2678 {-desc => 'colB'} | ORDER BY colB DESC
2680 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2682 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2685 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2686 { -desc => [qw/colB/], | colC ASC, colD ASC
2687 { -asc => [qw/colC colD/],|
2689 ===========================================================
2693 =head1 SPECIAL OPERATORS
2695 my $sqlmaker = SQL::Abstract->new(special_ops => [
2699 my ($self, $field, $op, $arg) = @_;
2705 handler => 'method_name',
2709 A "special operator" is a SQL syntactic clause that can be
2710 applied to a field, instead of a usual binary operator.
2713 WHERE field IN (?, ?, ?)
2714 WHERE field BETWEEN ? AND ?
2715 WHERE MATCH(field) AGAINST (?, ?)
2717 Special operators IN and BETWEEN are fairly standard and therefore
2718 are builtin within C<SQL::Abstract> (as the overridable methods
2719 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2720 like the MATCH .. AGAINST example above which is specific to MySQL,
2721 you can write your own operator handlers - supply a C<special_ops>
2722 argument to the C<new> method. That argument takes an arrayref of
2723 operator definitions; each operator definition is a hashref with two
2730 the regular expression to match the operator
2734 Either a coderef or a plain scalar method name. In both cases
2735 the expected return is C<< ($sql, @bind) >>.
2737 When supplied with a method name, it is simply called on the
2738 L<SQL::Abstract/> object as:
2740 $self->$method_name ($field, $op, $arg)
2744 $op is the part that matched the handler regex
2745 $field is the LHS of the operator
2748 When supplied with a coderef, it is called as:
2750 $coderef->($self, $field, $op, $arg)
2755 For example, here is an implementation
2756 of the MATCH .. AGAINST syntax for MySQL
2758 my $sqlmaker = SQL::Abstract->new(special_ops => [
2760 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2761 {regex => qr/^match$/i,
2763 my ($self, $field, $op, $arg) = @_;
2764 $arg = [$arg] if not ref $arg;
2765 my $label = $self->_quote($field);
2766 my ($placeholder) = $self->_convert('?');
2767 my $placeholders = join ", ", (($placeholder) x @$arg);
2768 my $sql = $self->_sqlcase('match') . " ($label) "
2769 . $self->_sqlcase('against') . " ($placeholders) ";
2770 my @bind = $self->_bindtype($field, @$arg);
2771 return ($sql, @bind);
2778 =head1 UNARY OPERATORS
2780 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2784 my ($self, $op, $arg) = @_;
2790 handler => 'method_name',
2794 A "unary operator" is a SQL syntactic clause that can be
2795 applied to a field - the operator goes before the field
2797 You can write your own operator handlers - supply a C<unary_ops>
2798 argument to the C<new> method. That argument takes an arrayref of
2799 operator definitions; each operator definition is a hashref with two
2806 the regular expression to match the operator
2810 Either a coderef or a plain scalar method name. In both cases
2811 the expected return is C<< $sql >>.
2813 When supplied with a method name, it is simply called on the
2814 L<SQL::Abstract/> object as:
2816 $self->$method_name ($op, $arg)
2820 $op is the part that matched the handler regex
2821 $arg is the RHS or argument of the operator
2823 When supplied with a coderef, it is called as:
2825 $coderef->($self, $op, $arg)
2833 Thanks to some benchmarking by Mark Stosberg, it turns out that
2834 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2835 I must admit this wasn't an intentional design issue, but it's a
2836 byproduct of the fact that you get to control your C<DBI> handles
2839 To maximize performance, use a code snippet like the following:
2841 # prepare a statement handle using the first row
2842 # and then reuse it for the rest of the rows
2844 for my $href (@array_of_hashrefs) {
2845 $stmt ||= $sql->insert('table', $href);
2846 $sth ||= $dbh->prepare($stmt);
2847 $sth->execute($sql->values($href));
2850 The reason this works is because the keys in your C<$href> are sorted
2851 internally by B<SQL::Abstract>. Thus, as long as your data retains
2852 the same structure, you only have to generate the SQL the first time
2853 around. On subsequent queries, simply use the C<values> function provided
2854 by this module to return your values in the correct order.
2856 However this depends on the values having the same type - if, for
2857 example, the values of a where clause may either have values
2858 (resulting in sql of the form C<column = ?> with a single bind
2859 value), or alternatively the values might be C<undef> (resulting in
2860 sql of the form C<column IS NULL> with no bind value) then the
2861 caching technique suggested will not work.
2865 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2866 really like this part (I do, at least). Building up a complex query
2867 can be as simple as the following:
2874 use CGI::FormBuilder;
2877 my $form = CGI::FormBuilder->new(...);
2878 my $sql = SQL::Abstract->new;
2880 if ($form->submitted) {
2881 my $field = $form->field;
2882 my $id = delete $field->{id};
2883 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2886 Of course, you would still have to connect using C<DBI> to run the
2887 query, but the point is that if you make your form look like your
2888 table, the actual query script can be extremely simplistic.
2890 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2891 a fast interface to returning and formatting data. I frequently
2892 use these three modules together to write complex database query
2893 apps in under 50 lines.
2899 =item * gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2901 =item * git: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2907 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2908 Great care has been taken to preserve the I<published> behavior
2909 documented in previous versions in the 1.* family; however,
2910 some features that were previously undocumented, or behaved
2911 differently from the documentation, had to be changed in order
2912 to clarify the semantics. Hence, client code that was relying
2913 on some dark areas of C<SQL::Abstract> v1.*
2914 B<might behave differently> in v1.50.
2916 The main changes are :
2922 support for literal SQL through the C<< \ [$sql, bind] >> syntax.
2926 support for the { operator => \"..." } construct (to embed literal SQL)
2930 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2934 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2938 defensive programming : check arguments
2942 fixed bug with global logic, which was previously implemented
2943 through global variables yielding side-effects. Prior versions would
2944 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2945 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2946 Now this is interpreted
2947 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2952 fixed semantics of _bindtype on array args
2956 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2957 we just avoid shifting arrays within that tree.
2961 dropped the C<_modlogic> function
2965 =head1 ACKNOWLEDGEMENTS
2967 There are a number of individuals that have really helped out with
2968 this module. Unfortunately, most of them submitted bugs via CPAN
2969 so I have no idea who they are! But the people I do know are:
2971 Ash Berlin (order_by hash term support)
2972 Matt Trout (DBIx::Class support)
2973 Mark Stosberg (benchmarking)
2974 Chas Owens (initial "IN" operator support)
2975 Philip Collins (per-field SQL functions)
2976 Eric Kolve (hashref "AND" support)
2977 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2978 Dan Kubb (support for "quote_char" and "name_sep")
2979 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2980 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2981 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2982 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2983 Oliver Charles (support for "RETURNING" after "INSERT")
2989 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
2993 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
2995 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
2997 For support, your best bet is to try the C<DBIx::Class> users mailing list.
2998 While not an official support venue, C<DBIx::Class> makes heavy use of
2999 C<SQL::Abstract>, and as such list members there are very familiar with
3000 how to create queries.
3004 This module is free software; you may copy this under the same
3005 terms as perl itself (either the GNU General Public License or
3006 the Artistic License)