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 '=')
693 if (! defined $rhs) {
695 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
702 ($lhs || $self->{_nested_func_lhs}),
709 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
713 $self->_convert('?'),
719 sub _where_hashpair_ARRAYREF {
720 my ($self, $k, $v) = @_;
723 my @v = @$v; # need copy because of shift below
724 $self->_debug("ARRAY($k) means distribute over elements");
726 # put apart first element if it is an operator (-and, -or)
728 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
732 my @distributed = map { {$k => $_} } @v;
735 $self->_debug("OP($op) reinjected into the distributed array");
736 unshift @distributed, $op;
739 my $logic = $op ? substr($op, 1) : '';
741 return $self->_recurse_where(\@distributed, $logic);
744 $self->_debug("empty ARRAY($k) means 0=1");
745 return ($self->{sqlfalse});
749 sub _where_hashpair_HASHREF {
750 my ($self, $k, $v, $logic) = @_;
753 local $self->{_nested_func_lhs} = $self->{_nested_func_lhs};
755 my ($all_sql, @all_bind);
757 for my $orig_op (sort keys %$v) {
758 my $val = $v->{$orig_op};
760 # put the operator in canonical form
763 # FIXME - we need to phase out dash-less ops
764 $op =~ s/^-//; # remove possible initial dash
765 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
766 $op =~ s/\s+/ /g; # compress whitespace
768 $self->_assert_pass_injection_guard($op);
771 $op =~ s/^is_not/IS NOT/i;
773 # so that -not_foo works correctly
774 $op =~ s/^not_/NOT /i;
776 # another retarded special case: foo => { $op => { -value => undef } }
777 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
783 # CASE: col-value logic modifiers
784 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
785 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
787 # CASE: special operators like -in or -between
788 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
789 my $handler = $special_op->{handler};
791 puke "No handler supplied for special operator $orig_op";
793 elsif (not ref $handler) {
794 ($sql, @bind) = $self->$handler ($k, $op, $val);
796 elsif (ref $handler eq 'CODE') {
797 ($sql, @bind) = $handler->($self, $k, $op, $val);
800 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
804 $self->_SWITCH_refkind($val, {
806 ARRAYREF => sub { # CASE: col => {op => \@vals}
807 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
810 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
811 my ($sub_sql, @sub_bind) = @$$val;
812 $self->_assert_bindval_matches_bindtype(@sub_bind);
813 $sql = join ' ', $self->_convert($self->_quote($k)),
814 $self->_sqlcase($op),
819 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
821 $op =~ /^not$/i ? 'is not' # legacy
822 : $op =~ $self->{equality_op} ? 'is'
823 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
824 : $op =~ $self->{inequality_op} ? 'is not'
825 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
826 : puke "unexpected operator '$orig_op' with undef operand";
828 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
831 FALLBACK => sub { # CASE: col => {op/func => $stuff}
833 # retain for proper column type bind
834 $self->{_nested_func_lhs} ||= $k;
836 ($sql, @bind) = $self->_where_unary_op ($op, $val);
839 $self->_convert($self->_quote($k)),
840 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
846 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
847 push @all_bind, @bind;
849 return ($all_sql, @all_bind);
852 sub _where_field_IS {
853 my ($self, $k, $op, $v) = @_;
855 my ($s) = $self->_SWITCH_refkind($v, {
858 $self->_convert($self->_quote($k)),
859 map { $self->_sqlcase($_)} ($op, 'null')
862 puke "$op can only take undef as argument";
869 sub _where_field_op_ARRAYREF {
870 my ($self, $k, $op, $vals) = @_;
872 my @vals = @$vals; #always work on a copy
875 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
877 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
880 # see if the first element is an -and/-or op
882 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
887 # a long standing API wart - an attempt to change this behavior during
888 # the 1.50 series failed *spectacularly*. Warn instead and leave the
893 (!$logic or $logic eq 'OR')
895 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
898 belch "A multi-element arrayref as an argument to the inequality op '$o' "
899 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
900 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
904 # distribute $op over each remaining member of @vals, append logic if exists
905 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
909 # try to DWIM on equality operators
911 $op =~ $self->{equality_op} ? $self->{sqlfalse}
912 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
913 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
914 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
915 : puke "operator '$op' applied on an empty array (field '$k')";
920 sub _where_hashpair_SCALARREF {
921 my ($self, $k, $v) = @_;
922 $self->_debug("SCALAR($k) means literal SQL: $$v");
923 my $sql = $self->_quote($k) . " " . $$v;
927 # literal SQL with bind
928 sub _where_hashpair_ARRAYREFREF {
929 my ($self, $k, $v) = @_;
930 $self->_debug("REF($k) means literal SQL: @${$v}");
931 my ($sql, @bind) = @$$v;
932 $self->_assert_bindval_matches_bindtype(@bind);
933 $sql = $self->_quote($k) . " " . $sql;
934 return ($sql, @bind );
937 # literal SQL without bind
938 sub _where_hashpair_SCALAR {
939 my ($self, $k, $v) = @_;
940 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
941 my $sql = join ' ', $self->_convert($self->_quote($k)),
942 $self->_sqlcase($self->{cmp}),
943 $self->_convert('?');
944 my @bind = $self->_bindtype($k, $v);
945 return ( $sql, @bind);
949 sub _where_hashpair_UNDEF {
950 my ($self, $k, $v) = @_;
951 $self->_debug("UNDEF($k) means IS NULL");
952 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
956 #======================================================================
957 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
958 #======================================================================
961 sub _where_SCALARREF {
962 my ($self, $where) = @_;
965 $self->_debug("SCALAR(*top) means literal SQL: $$where");
971 my ($self, $where) = @_;
974 $self->_debug("NOREF(*top) means literal SQL: $where");
985 #======================================================================
986 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
987 #======================================================================
990 sub _where_field_BETWEEN {
991 my ($self, $k, $op, $vals) = @_;
993 my ($label, $and, $placeholder);
994 $label = $self->_convert($self->_quote($k));
995 $and = ' ' . $self->_sqlcase('and') . ' ';
996 $placeholder = $self->_convert('?');
997 $op = $self->_sqlcase($op);
999 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1001 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1002 ARRAYREFREF => sub {
1003 my ($s, @b) = @$$vals;
1004 $self->_assert_bindval_matches_bindtype(@b);
1011 puke $invalid_args if @$vals != 2;
1013 my (@all_sql, @all_bind);
1014 foreach my $val (@$vals) {
1015 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1017 return ($placeholder, $self->_bindtype($k, $val) );
1022 ARRAYREFREF => sub {
1023 my ($sql, @bind) = @$$val;
1024 $self->_assert_bindval_matches_bindtype(@bind);
1025 return ($sql, @bind);
1028 my ($func, $arg, @rest) = %$val;
1029 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1030 if (@rest or $func !~ /^ \- (.+)/x);
1031 local $self->{_nested_func_lhs} = $k;
1032 $self->_where_unary_op ($1 => $arg);
1038 push @all_sql, $sql;
1039 push @all_bind, @bind;
1043 (join $and, @all_sql),
1052 my $sql = "( $label $op $clause )";
1053 return ($sql, @bind)
1057 sub _where_field_IN {
1058 my ($self, $k, $op, $vals) = @_;
1060 # backwards compatibility : if scalar, force into an arrayref
1061 $vals = [$vals] if defined $vals && ! ref $vals;
1063 my ($label) = $self->_convert($self->_quote($k));
1064 my ($placeholder) = $self->_convert('?');
1065 $op = $self->_sqlcase($op);
1067 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1068 ARRAYREF => sub { # list of choices
1069 if (@$vals) { # nonempty list
1070 my (@all_sql, @all_bind);
1072 for my $val (@$vals) {
1073 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1075 return ($placeholder, $val);
1080 ARRAYREFREF => sub {
1081 my ($sql, @bind) = @$$val;
1082 $self->_assert_bindval_matches_bindtype(@bind);
1083 return ($sql, @bind);
1086 my ($func, $arg, @rest) = %$val;
1087 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1088 if (@rest or $func !~ /^ \- (.+)/x);
1089 local $self->{_nested_func_lhs} = $k;
1090 $self->_where_unary_op ($1 => $arg);
1094 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1095 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1096 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1097 . 'will emit the logically correct SQL instead of raising this exception)'
1101 push @all_sql, $sql;
1102 push @all_bind, @bind;
1106 sprintf ('%s %s ( %s )',
1109 join (', ', @all_sql)
1111 $self->_bindtype($k, @all_bind),
1114 else { # empty list : some databases won't understand "IN ()", so DWIM
1115 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1120 SCALARREF => sub { # literal SQL
1121 my $sql = $self->_open_outer_paren ($$vals);
1122 return ("$label $op ( $sql )");
1124 ARRAYREFREF => sub { # literal SQL with bind
1125 my ($sql, @bind) = @$$vals;
1126 $self->_assert_bindval_matches_bindtype(@bind);
1127 $sql = $self->_open_outer_paren ($sql);
1128 return ("$label $op ( $sql )", @bind);
1132 puke "Argument passed to the '$op' operator can not be undefined";
1136 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1140 return ($sql, @bind);
1143 # Some databases (SQLite) treat col IN (1, 2) different from
1144 # col IN ( (1, 2) ). Use this to strip all outer parens while
1145 # adding them back in the corresponding method
1146 sub _open_outer_paren {
1147 my ($self, $sql) = @_;
1148 $sql = $1 while $sql =~ /^ \s* \( (.*) \) \s* $/xs;
1153 #======================================================================
1155 #======================================================================
1158 my ($self, $arg) = @_;
1161 for my $c ($self->_order_by_chunks ($arg) ) {
1162 $self->_SWITCH_refkind ($c, {
1163 SCALAR => sub { push @sql, $c },
1164 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1170 $self->_sqlcase(' order by'),
1176 return wantarray ? ($sql, @bind) : $sql;
1179 sub _order_by_chunks {
1180 my ($self, $arg) = @_;
1182 return $self->_SWITCH_refkind($arg, {
1185 map { $self->_order_by_chunks ($_ ) } @$arg;
1188 ARRAYREFREF => sub {
1189 my ($s, @b) = @$$arg;
1190 $self->_assert_bindval_matches_bindtype(@b);
1194 SCALAR => sub {$self->_quote($arg)},
1196 UNDEF => sub {return () },
1198 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1201 # get first pair in hash
1202 my ($key, $val, @rest) = %$arg;
1204 return () unless $key;
1206 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1207 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1213 for my $c ($self->_order_by_chunks ($val)) {
1216 $self->_SWITCH_refkind ($c, {
1221 ($sql, @bind) = @$c;
1225 $sql = $sql . ' ' . $self->_sqlcase($direction);
1227 push @ret, [ $sql, @bind];
1236 #======================================================================
1237 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1238 #======================================================================
1243 $self->_SWITCH_refkind($from, {
1244 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1245 SCALAR => sub {$self->_quote($from)},
1246 SCALARREF => sub {$$from},
1251 #======================================================================
1253 #======================================================================
1255 # highly optimized, as it's called way too often
1257 # my ($self, $label) = @_;
1259 return '' unless defined $_[1];
1260 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1262 unless ($_[0]->{quote_char}) {
1263 $_[0]->_assert_pass_injection_guard($_[1]);
1267 my $qref = ref $_[0]->{quote_char};
1270 ($l, $r) = ( $_[0]->{quote_char}, $_[0]->{quote_char} );
1272 elsif ($qref eq 'ARRAY') {
1273 ($l, $r) = @{$_[0]->{quote_char}};
1276 puke "Unsupported quote_char format: $_[0]->{quote_char}";
1278 my $esc = $_[0]->{escape_char} || $r;
1280 # parts containing * are naturally unquoted
1281 return join( $_[0]->{name_sep}||'', map
1282 { $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } }
1283 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1288 # Conversion, if applicable
1290 #my ($self, $arg) = @_;
1291 if ($_[0]->{convert}) {
1292 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1299 #my ($self, $col, @vals) = @_;
1300 # called often - tighten code
1301 return $_[0]->{bindtype} eq 'columns'
1302 ? map {[$_[1], $_]} @_[2 .. $#_]
1307 # Dies if any element of @bind is not in [colname => value] format
1308 # if bindtype is 'columns'.
1309 sub _assert_bindval_matches_bindtype {
1310 # my ($self, @bind) = @_;
1312 if ($self->{bindtype} eq 'columns') {
1314 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1315 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1321 sub _join_sql_clauses {
1322 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1324 if (@$clauses_aref > 1) {
1325 my $join = " " . $self->_sqlcase($logic) . " ";
1326 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1327 return ($sql, @$bind_aref);
1329 elsif (@$clauses_aref) {
1330 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1333 return (); # if no SQL, ignore @$bind_aref
1338 # Fix SQL case, if so requested
1340 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1341 # don't touch the argument ... crooked logic, but let's not change it!
1342 return $_[0]->{case} ? $_[1] : uc($_[1]);
1346 #======================================================================
1347 # DISPATCHING FROM REFKIND
1348 #======================================================================
1351 my ($self, $data) = @_;
1353 return 'UNDEF' unless defined $data;
1355 # blessed objects are treated like scalars
1356 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1358 return 'SCALAR' unless $ref;
1361 while ($ref eq 'REF') {
1363 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1367 return ($ref||'SCALAR') . ('REF' x $n_steps);
1371 my ($self, $data) = @_;
1372 my @try = ($self->_refkind($data));
1373 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1374 push @try, 'FALLBACK';
1378 sub _METHOD_FOR_refkind {
1379 my ($self, $meth_prefix, $data) = @_;
1382 for (@{$self->_try_refkind($data)}) {
1383 $method = $self->can($meth_prefix."_".$_)
1387 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1391 sub _SWITCH_refkind {
1392 my ($self, $data, $dispatch_table) = @_;
1395 for (@{$self->_try_refkind($data)}) {
1396 $coderef = $dispatch_table->{$_}
1400 puke "no dispatch entry for ".$self->_refkind($data)
1409 #======================================================================
1410 # VALUES, GENERATE, AUTOLOAD
1411 #======================================================================
1413 # LDNOTE: original code from nwiger, didn't touch code in that section
1414 # I feel the AUTOLOAD stuff should not be the default, it should
1415 # only be activated on explicit demand by user.
1419 my $data = shift || return;
1420 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1421 unless ref $data eq 'HASH';
1424 foreach my $k ( sort keys %$data ) {
1425 my $v = $data->{$k};
1426 $self->_SWITCH_refkind($v, {
1428 if ($self->{array_datatypes}) { # array datatype
1429 push @all_bind, $self->_bindtype($k, $v);
1431 else { # literal SQL with bind
1432 my ($sql, @bind) = @$v;
1433 $self->_assert_bindval_matches_bindtype(@bind);
1434 push @all_bind, @bind;
1437 ARRAYREFREF => sub { # literal SQL with bind
1438 my ($sql, @bind) = @${$v};
1439 $self->_assert_bindval_matches_bindtype(@bind);
1440 push @all_bind, @bind;
1442 SCALARREF => sub { # literal SQL without bind
1444 SCALAR_or_UNDEF => sub {
1445 push @all_bind, $self->_bindtype($k, $v);
1456 my(@sql, @sqlq, @sqlv);
1460 if ($ref eq 'HASH') {
1461 for my $k (sort keys %$_) {
1464 my $label = $self->_quote($k);
1465 if ($r eq 'ARRAY') {
1466 # literal SQL with bind
1467 my ($sql, @bind) = @$v;
1468 $self->_assert_bindval_matches_bindtype(@bind);
1469 push @sqlq, "$label = $sql";
1471 } elsif ($r eq 'SCALAR') {
1472 # literal SQL without bind
1473 push @sqlq, "$label = $$v";
1475 push @sqlq, "$label = ?";
1476 push @sqlv, $self->_bindtype($k, $v);
1479 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1480 } elsif ($ref eq 'ARRAY') {
1481 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1484 if ($r eq 'ARRAY') { # literal SQL with bind
1485 my ($sql, @bind) = @$v;
1486 $self->_assert_bindval_matches_bindtype(@bind);
1489 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1490 # embedded literal SQL
1497 push @sql, '(' . join(', ', @sqlq) . ')';
1498 } elsif ($ref eq 'SCALAR') {
1502 # strings get case twiddled
1503 push @sql, $self->_sqlcase($_);
1507 my $sql = join ' ', @sql;
1509 # this is pretty tricky
1510 # if ask for an array, return ($stmt, @bind)
1511 # otherwise, s/?/shift @sqlv/ to put it inline
1513 return ($sql, @sqlv);
1515 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1516 ref $d ? $d->[1] : $d/e;
1525 # This allows us to check for a local, then _form, attr
1527 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1528 return $self->generate($name, @_);
1539 SQL::Abstract - Generate SQL from Perl data structures
1545 my $sql = SQL::Abstract->new;
1547 my($stmt, @bind) = $sql->select($source, \@fields, \%where, \@order);
1549 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1551 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1553 my($stmt, @bind) = $sql->delete($table, \%where);
1555 # Then, use these in your DBI statements
1556 my $sth = $dbh->prepare($stmt);
1557 $sth->execute(@bind);
1559 # Just generate the WHERE clause
1560 my($stmt, @bind) = $sql->where(\%where, \@order);
1562 # Return values in the same order, for hashed queries
1563 # See PERFORMANCE section for more details
1564 my @bind = $sql->values(\%fieldvals);
1568 This module was inspired by the excellent L<DBIx::Abstract>.
1569 However, in using that module I found that what I really wanted
1570 to do was generate SQL, but still retain complete control over my
1571 statement handles and use the DBI interface. So, I set out to
1572 create an abstract SQL generation module.
1574 While based on the concepts used by L<DBIx::Abstract>, there are
1575 several important differences, especially when it comes to WHERE
1576 clauses. I have modified the concepts used to make the SQL easier
1577 to generate from Perl data structures and, IMO, more intuitive.
1578 The underlying idea is for this module to do what you mean, based
1579 on the data structures you provide it. The big advantage is that
1580 you don't have to modify your code every time your data changes,
1581 as this module figures it out.
1583 To begin with, an SQL INSERT is as easy as just specifying a hash
1584 of C<key=value> pairs:
1587 name => 'Jimbo Bobson',
1588 phone => '123-456-7890',
1589 address => '42 Sister Lane',
1590 city => 'St. Louis',
1591 state => 'Louisiana',
1594 The SQL can then be generated with this:
1596 my($stmt, @bind) = $sql->insert('people', \%data);
1598 Which would give you something like this:
1600 $stmt = "INSERT INTO people
1601 (address, city, name, phone, state)
1602 VALUES (?, ?, ?, ?, ?)";
1603 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1604 '123-456-7890', 'Louisiana');
1606 These are then used directly in your DBI code:
1608 my $sth = $dbh->prepare($stmt);
1609 $sth->execute(@bind);
1611 =head2 Inserting and Updating Arrays
1613 If your database has array types (like for example Postgres),
1614 activate the special option C<< array_datatypes => 1 >>
1615 when creating the C<SQL::Abstract> object.
1616 Then you may use an arrayref to insert and update database array types:
1618 my $sql = SQL::Abstract->new(array_datatypes => 1);
1620 planets => [qw/Mercury Venus Earth Mars/]
1623 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1627 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1629 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1632 =head2 Inserting and Updating SQL
1634 In order to apply SQL functions to elements of your C<%data> you may
1635 specify a reference to an arrayref for the given hash value. For example,
1636 if you need to execute the Oracle C<to_date> function on a value, you can
1637 say something like this:
1641 date_entered => \["to_date(?,'MM/DD/YYYY')", "03/02/2003"],
1644 The first value in the array is the actual SQL. Any other values are
1645 optional and would be included in the bind values array. This gives
1648 my($stmt, @bind) = $sql->insert('people', \%data);
1650 $stmt = "INSERT INTO people (name, date_entered)
1651 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1652 @bind = ('Bill', '03/02/2003');
1654 An UPDATE is just as easy, all you change is the name of the function:
1656 my($stmt, @bind) = $sql->update('people', \%data);
1658 Notice that your C<%data> isn't touched; the module will generate
1659 the appropriately quirky SQL for you automatically. Usually you'll
1660 want to specify a WHERE clause for your UPDATE, though, which is
1661 where handling C<%where> hashes comes in handy...
1663 =head2 Complex where statements
1665 This module can generate pretty complicated WHERE statements
1666 easily. For example, simple C<key=value> pairs are taken to mean
1667 equality, and if you want to see if a field is within a set
1668 of values, you can use an arrayref. Let's say we wanted to
1669 SELECT some data based on this criteria:
1672 requestor => 'inna',
1673 worker => ['nwiger', 'rcwe', 'sfz'],
1674 status => { '!=', 'completed' }
1677 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1679 The above would give you something like this:
1681 $stmt = "SELECT * FROM tickets WHERE
1682 ( requestor = ? ) AND ( status != ? )
1683 AND ( worker = ? OR worker = ? OR worker = ? )";
1684 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1686 Which you could then use in DBI code like so:
1688 my $sth = $dbh->prepare($stmt);
1689 $sth->execute(@bind);
1695 The functions are simple. There's one for each major SQL operation,
1696 and a constructor you use first. The arguments are specified in a
1697 similar order to each function (table, then fields, then a where
1698 clause) to try and simplify things.
1703 =head2 new(option => 'value')
1705 The C<new()> function takes a list of options and values, and returns
1706 a new B<SQL::Abstract> object which can then be used to generate SQL
1707 through the methods below. The options accepted are:
1713 If set to 'lower', then SQL will be generated in all lowercase. By
1714 default SQL is generated in "textbook" case meaning something like:
1716 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1718 Any setting other than 'lower' is ignored.
1722 This determines what the default comparison operator is. By default
1723 it is C<=>, meaning that a hash like this:
1725 %where = (name => 'nwiger', email => 'nate@wiger.org');
1727 Will generate SQL like this:
1729 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1731 However, you may want loose comparisons by default, so if you set
1732 C<cmp> to C<like> you would get SQL such as:
1734 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1736 You can also override the comparison on an individual basis - see
1737 the huge section on L</"WHERE CLAUSES"> at the bottom.
1739 =item sqltrue, sqlfalse
1741 Expressions for inserting boolean values within SQL statements.
1742 By default these are C<1=1> and C<1=0>. They are used
1743 by the special operators C<-in> and C<-not_in> for generating
1744 correct SQL even when the argument is an empty array (see below).
1748 This determines the default logical operator for multiple WHERE
1749 statements in arrays or hashes. If absent, the default logic is "or"
1750 for arrays, and "and" for hashes. This means that a WHERE
1754 event_date => {'>=', '2/13/99'},
1755 event_date => {'<=', '4/24/03'},
1758 will generate SQL like this:
1760 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1762 This is probably not what you want given this query, though (look
1763 at the dates). To change the "OR" to an "AND", simply specify:
1765 my $sql = SQL::Abstract->new(logic => 'and');
1767 Which will change the above C<WHERE> to:
1769 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1771 The logic can also be changed locally by inserting
1772 a modifier in front of an arrayref :
1774 @where = (-and => [event_date => {'>=', '2/13/99'},
1775 event_date => {'<=', '4/24/03'} ]);
1777 See the L</"WHERE CLAUSES"> section for explanations.
1781 This will automatically convert comparisons using the specified SQL
1782 function for both column and value. This is mostly used with an argument
1783 of C<upper> or C<lower>, so that the SQL will have the effect of
1784 case-insensitive "searches". For example, this:
1786 $sql = SQL::Abstract->new(convert => 'upper');
1787 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1789 Will turn out the following SQL:
1791 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1793 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1794 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1795 not validate this option; it will just pass through what you specify verbatim).
1799 This is a kludge because many databases suck. For example, you can't
1800 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1801 Instead, you have to use C<bind_param()>:
1803 $sth->bind_param(1, 'reg data');
1804 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1806 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1807 which loses track of which field each slot refers to. Fear not.
1809 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1810 Currently, you can specify either C<normal> (default) or C<columns>. If you
1811 specify C<columns>, you will get an array that looks like this:
1813 my $sql = SQL::Abstract->new(bindtype => 'columns');
1814 my($stmt, @bind) = $sql->insert(...);
1817 [ 'column1', 'value1' ],
1818 [ 'column2', 'value2' ],
1819 [ 'column3', 'value3' ],
1822 You can then iterate through this manually, using DBI's C<bind_param()>.
1824 $sth->prepare($stmt);
1827 my($col, $data) = @$_;
1828 if ($col eq 'details' || $col eq 'comments') {
1829 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1830 } elsif ($col eq 'image') {
1831 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1833 $sth->bind_param($i, $data);
1837 $sth->execute; # execute without @bind now
1839 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1840 Basically, the advantage is still that you don't have to care which fields
1841 are or are not included. You could wrap that above C<for> loop in a simple
1842 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1843 get a layer of abstraction over manual SQL specification.
1845 Note that if you set L</bindtype> to C<columns>, the C<\[$sql, @bind]>
1846 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1847 will expect the bind values in this format.
1851 This is the character that a table or column name will be quoted
1852 with. By default this is an empty string, but you could set it to
1853 the character C<`>, to generate SQL like this:
1855 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1857 Alternatively, you can supply an array ref of two items, the first being the left
1858 hand quote character, and the second the right hand quote character. For
1859 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1860 that generates SQL like this:
1862 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1864 Quoting is useful if you have tables or columns names that are reserved
1865 words in your database's SQL dialect.
1869 This is the character that will be used to escape L</quote_char>s appearing
1870 in an identifier before it has been quoted.
1872 The paramter default in case of a single L</quote_char> character is the quote
1875 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1876 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
1877 of the B<opening (left)> L</quote_char> within the identifier are currently left
1878 untouched. The default for opening-closing-style quotes may change in future
1879 versions, thus you are B<strongly encouraged> to specify the escape character
1884 This is the character that separates a table and column name. It is
1885 necessary to specify this when the C<quote_char> option is selected,
1886 so that tables and column names can be individually quoted like this:
1888 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1890 =item injection_guard
1892 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1893 column name specified in a query structure. This is a safety mechanism to avoid
1894 injection attacks when mishandling user input e.g.:
1896 my %condition_as_column_value_pairs = get_values_from_user();
1897 $sqla->select( ... , \%condition_as_column_value_pairs );
1899 If the expression matches an exception is thrown. Note that literal SQL
1900 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1902 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1904 =item array_datatypes
1906 When this option is true, arrayrefs in INSERT or UPDATE are
1907 interpreted as array datatypes and are passed directly
1909 When this option is false, arrayrefs are interpreted
1910 as literal SQL, just like refs to arrayrefs
1911 (but this behavior is for backwards compatibility; when writing
1912 new queries, use the "reference to arrayref" syntax
1918 Takes a reference to a list of "special operators"
1919 to extend the syntax understood by L<SQL::Abstract>.
1920 See section L</"SPECIAL OPERATORS"> for details.
1924 Takes a reference to a list of "unary operators"
1925 to extend the syntax understood by L<SQL::Abstract>.
1926 See section L</"UNARY OPERATORS"> for details.
1932 =head2 insert($table, \@values || \%fieldvals, \%options)
1934 This is the simplest function. You simply give it a table name
1935 and either an arrayref of values or hashref of field/value pairs.
1936 It returns an SQL INSERT statement and a list of bind values.
1937 See the sections on L</"Inserting and Updating Arrays"> and
1938 L</"Inserting and Updating SQL"> for information on how to insert
1939 with those data types.
1941 The optional C<\%options> hash reference may contain additional
1942 options to generate the insert SQL. Currently supported options
1949 Takes either a scalar of raw SQL fields, or an array reference of
1950 field names, and adds on an SQL C<RETURNING> statement at the end.
1951 This allows you to return data generated by the insert statement
1952 (such as row IDs) without performing another C<SELECT> statement.
1953 Note, however, this is not part of the SQL standard and may not
1954 be supported by all database engines.
1958 =head2 update($table, \%fieldvals, \%where)
1960 This takes a table, hashref of field/value pairs, and an optional
1961 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1963 See the sections on L</"Inserting and Updating Arrays"> and
1964 L</"Inserting and Updating SQL"> for information on how to insert
1965 with those data types.
1967 =head2 select($source, $fields, $where, $order)
1969 This returns a SQL SELECT statement and associated list of bind values, as
1970 specified by the arguments :
1976 Specification of the 'FROM' part of the statement.
1977 The argument can be either a plain scalar (interpreted as a table
1978 name, will be quoted), or an arrayref (interpreted as a list
1979 of table names, joined by commas, quoted), or a scalarref
1980 (literal table name, not quoted), or a ref to an arrayref
1981 (list of literal table names, joined by commas, not quoted).
1985 Specification of the list of fields to retrieve from
1987 The argument can be either an arrayref (interpreted as a list
1988 of field names, will be joined by commas and quoted), or a
1989 plain scalar (literal SQL, not quoted).
1990 Please observe that this API is not as flexible as that of
1991 the first argument C<$source>, for backwards compatibility reasons.
1995 Optional argument to specify the WHERE part of the query.
1996 The argument is most often a hashref, but can also be
1997 an arrayref or plain scalar --
1998 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2002 Optional argument to specify the ORDER BY part of the query.
2003 The argument can be a scalar, a hashref or an arrayref
2004 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2010 =head2 delete($table, \%where)
2012 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2013 It returns an SQL DELETE statement and list of bind values.
2015 =head2 where(\%where, \@order)
2017 This is used to generate just the WHERE clause. For example,
2018 if you have an arbitrary data structure and know what the
2019 rest of your SQL is going to look like, but want an easy way
2020 to produce a WHERE clause, use this. It returns an SQL WHERE
2021 clause and list of bind values.
2024 =head2 values(\%data)
2026 This just returns the values from the hash C<%data>, in the same
2027 order that would be returned from any of the other above queries.
2028 Using this allows you to markedly speed up your queries if you
2029 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2031 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2033 Warning: This is an experimental method and subject to change.
2035 This returns arbitrarily generated SQL. It's a really basic shortcut.
2036 It will return two different things, depending on return context:
2038 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2039 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2041 These would return the following:
2043 # First calling form
2044 $stmt = "CREATE TABLE test (?, ?)";
2045 @bind = (field1, field2);
2047 # Second calling form
2048 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2050 Depending on what you're trying to do, it's up to you to choose the correct
2051 format. In this example, the second form is what you would want.
2055 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2059 ALTER SESSION SET nls_date_format = 'MM/YY'
2061 You get the idea. Strings get their case twiddled, but everything
2062 else remains verbatim.
2064 =head1 WHERE CLAUSES
2068 This module uses a variation on the idea from L<DBIx::Abstract>. It
2069 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2070 module is that things in arrays are OR'ed, and things in hashes
2073 The easiest way to explain is to show lots of examples. After
2074 each C<%where> hash shown, it is assumed you used:
2076 my($stmt, @bind) = $sql->where(\%where);
2078 However, note that the C<%where> hash can be used directly in any
2079 of the other functions as well, as described above.
2081 =head2 Key-value pairs
2083 So, let's get started. To begin, a simple hash:
2087 status => 'completed'
2090 Is converted to SQL C<key = val> statements:
2092 $stmt = "WHERE user = ? AND status = ?";
2093 @bind = ('nwiger', 'completed');
2095 One common thing I end up doing is having a list of values that
2096 a field can be in. To do this, simply specify a list inside of
2101 status => ['assigned', 'in-progress', 'pending'];
2104 This simple code will create the following:
2106 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2107 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2109 A field associated to an empty arrayref will be considered a
2110 logical false and will generate 0=1.
2112 =head2 Tests for NULL values
2114 If the value part is C<undef> then this is converted to SQL <IS NULL>
2123 $stmt = "WHERE user = ? AND status IS NULL";
2126 To test if a column IS NOT NULL:
2130 status => { '!=', undef },
2133 =head2 Specific comparison operators
2135 If you want to specify a different type of operator for your comparison,
2136 you can use a hashref for a given column:
2140 status => { '!=', 'completed' }
2143 Which would generate:
2145 $stmt = "WHERE user = ? AND status != ?";
2146 @bind = ('nwiger', 'completed');
2148 To test against multiple values, just enclose the values in an arrayref:
2150 status => { '=', ['assigned', 'in-progress', 'pending'] };
2152 Which would give you:
2154 "WHERE status = ? OR status = ? OR status = ?"
2157 The hashref can also contain multiple pairs, in which case it is expanded
2158 into an C<AND> of its elements:
2162 status => { '!=', 'completed', -not_like => 'pending%' }
2165 # Or more dynamically, like from a form
2166 $where{user} = 'nwiger';
2167 $where{status}{'!='} = 'completed';
2168 $where{status}{'-not_like'} = 'pending%';
2170 # Both generate this
2171 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2172 @bind = ('nwiger', 'completed', 'pending%');
2175 To get an OR instead, you can combine it with the arrayref idea:
2179 priority => [ { '=', 2 }, { '>', 5 } ]
2182 Which would generate:
2184 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2185 @bind = ('2', '5', 'nwiger');
2187 If you want to include literal SQL (with or without bind values), just use a
2188 scalar reference or array reference as the value:
2191 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2192 date_expires => { '<' => \"now()" }
2195 Which would generate:
2197 $stmt = "WHERE date_entered > "to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2198 @bind = ('11/26/2008');
2201 =head2 Logic and nesting operators
2203 In the example above,
2204 there is a subtle trap if you want to say something like
2205 this (notice the C<AND>):
2207 WHERE priority != ? AND priority != ?
2209 Because, in Perl you I<can't> do this:
2211 priority => { '!=', 2, '!=', 1 }
2213 As the second C<!=> key will obliterate the first. The solution
2214 is to use the special C<-modifier> form inside an arrayref:
2216 priority => [ -and => {'!=', 2},
2220 Normally, these would be joined by C<OR>, but the modifier tells it
2221 to use C<AND> instead. (Hint: You can use this in conjunction with the
2222 C<logic> option to C<new()> in order to change the way your queries
2223 work by default.) B<Important:> Note that the C<-modifier> goes
2224 B<INSIDE> the arrayref, as an extra first element. This will
2225 B<NOT> do what you think it might:
2227 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2229 Here is a quick list of equivalencies, since there is some overlap:
2232 status => {'!=', 'completed', 'not like', 'pending%' }
2233 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2236 status => {'=', ['assigned', 'in-progress']}
2237 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2238 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2242 =head2 Special operators : IN, BETWEEN, etc.
2244 You can also use the hashref format to compare a list of fields using the
2245 C<IN> comparison operator, by specifying the list as an arrayref:
2248 status => 'completed',
2249 reportid => { -in => [567, 2335, 2] }
2252 Which would generate:
2254 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2255 @bind = ('completed', '567', '2335', '2');
2257 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2260 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2261 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2262 'sqltrue' (by default : C<1=1>).
2264 In addition to the array you can supply a chunk of literal sql or
2265 literal sql with bind:
2268 customer => { -in => \[
2269 'SELECT cust_id FROM cust WHERE balance > ?',
2272 status => { -in => \'SELECT status_codes FROM states' },
2278 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2279 AND status IN ( SELECT status_codes FROM states )
2283 Finally, if the argument to C<-in> is not a reference, it will be
2284 treated as a single-element array.
2286 Another pair of operators is C<-between> and C<-not_between>,
2287 used with an arrayref of two values:
2291 completion_date => {
2292 -not_between => ['2002-10-01', '2003-02-06']
2298 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2300 Just like with C<-in> all plausible combinations of literal SQL
2304 start0 => { -between => [ 1, 2 ] },
2305 start1 => { -between => \["? AND ?", 1, 2] },
2306 start2 => { -between => \"lower(x) AND upper(y)" },
2307 start3 => { -between => [
2309 \["upper(?)", 'stuff' ],
2316 ( start0 BETWEEN ? AND ? )
2317 AND ( start1 BETWEEN ? AND ? )
2318 AND ( start2 BETWEEN lower(x) AND upper(y) )
2319 AND ( start3 BETWEEN lower(x) AND upper(?) )
2321 @bind = (1, 2, 1, 2, 'stuff');
2324 These are the two builtin "special operators"; but the
2325 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2327 =head2 Unary operators: bool
2329 If you wish to test against boolean columns or functions within your
2330 database you can use the C<-bool> and C<-not_bool> operators. For
2331 example to test the column C<is_user> being true and the column
2332 C<is_enabled> being false you would use:-
2336 -not_bool => 'is_enabled',
2341 WHERE is_user AND NOT is_enabled
2343 If a more complex combination is required, testing more conditions,
2344 then you should use the and/or operators:-
2349 -not_bool => { two=> { -rlike => 'bar' } },
2350 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2361 (NOT ( three = ? OR three > ? ))
2364 =head2 Nested conditions, -and/-or prefixes
2366 So far, we've seen how multiple conditions are joined with a top-level
2367 C<AND>. We can change this by putting the different conditions we want in
2368 hashes and then putting those hashes in an array. For example:
2373 status => { -like => ['pending%', 'dispatched'] },
2377 status => 'unassigned',
2381 This data structure would create the following:
2383 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2384 OR ( user = ? AND status = ? ) )";
2385 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2388 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2389 to change the logic inside :
2395 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2396 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2403 WHERE ( user = ? AND (
2404 ( workhrs > ? AND geo = ? )
2405 OR ( workhrs < ? OR geo = ? )
2408 =head3 Algebraic inconsistency, for historical reasons
2410 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2411 operator goes C<outside> of the nested structure; whereas when connecting
2412 several constraints on one column, the C<-and> operator goes
2413 C<inside> the arrayref. Here is an example combining both features :
2416 -and => [a => 1, b => 2],
2417 -or => [c => 3, d => 4],
2418 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2423 WHERE ( ( ( a = ? AND b = ? )
2424 OR ( c = ? OR d = ? )
2425 OR ( e LIKE ? AND e LIKE ? ) ) )
2427 This difference in syntax is unfortunate but must be preserved for
2428 historical reasons. So be careful : the two examples below would
2429 seem algebraically equivalent, but they are not
2431 {col => [-and => {-like => 'foo%'}, {-like => '%bar'}]}
2432 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2434 [-and => {col => {-like => 'foo%'}, {col => {-like => '%bar'}}]]
2435 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2438 =head2 Literal SQL and value type operators
2440 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2441 side" is a column name and the "right side" is a value (normally rendered as
2442 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2443 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2444 alter this behavior. There are several ways of doing so.
2448 This is a virtual operator that signals the string to its right side is an
2449 identifier (a column name) and not a value. For example to compare two
2450 columns you would write:
2453 priority => { '<', 2 },
2454 requestor => { -ident => 'submitter' },
2459 $stmt = "WHERE priority < ? AND requestor = submitter";
2462 If you are maintaining legacy code you may see a different construct as
2463 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2468 This is a virtual operator that signals that the construct to its right side
2469 is a value to be passed to DBI. This is for example necessary when you want
2470 to write a where clause against an array (for RDBMS that support such
2471 datatypes). For example:
2474 array => { -value => [1, 2, 3] }
2479 $stmt = 'WHERE array = ?';
2480 @bind = ([1, 2, 3]);
2482 Note that if you were to simply say:
2488 the result would probably not be what you wanted:
2490 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2495 Finally, sometimes only literal SQL will do. To include a random snippet
2496 of SQL verbatim, you specify it as a scalar reference. Consider this only
2497 as a last resort. Usually there is a better way. For example:
2500 priority => { '<', 2 },
2501 requestor => { -in => \'(SELECT name FROM hitmen)' },
2506 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2509 Note that in this example, you only get one bind parameter back, since
2510 the verbatim SQL is passed as part of the statement.
2514 Never use untrusted input as a literal SQL argument - this is a massive
2515 security risk (there is no way to check literal snippets for SQL
2516 injections and other nastyness). If you need to deal with untrusted input
2517 use literal SQL with placeholders as described next.
2519 =head3 Literal SQL with placeholders and bind values (subqueries)
2521 If the literal SQL to be inserted has placeholders and bind values,
2522 use a reference to an arrayref (yes this is a double reference --
2523 not so common, but perfectly legal Perl). For example, to find a date
2524 in Postgres you can use something like this:
2527 date_column => \[q/= date '2008-09-30' - ?::integer/, 10/]
2532 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2535 Note that you must pass the bind values in the same format as they are returned
2536 by L</where>. That means that if you set L</bindtype> to C<columns>, you must
2537 provide the bind values in the C<< [ column_meta => value ] >> format, where
2538 C<column_meta> is an opaque scalar value; most commonly the column name, but
2539 you can use any scalar value (including references and blessed references),
2540 L<SQL::Abstract> will simply pass it through intact. So if C<bindtype> is set
2541 to C<columns> the above example will look like:
2544 date_column => \[q/= date '2008-09-30' - ?::integer/, [ dummy => 10 ]/]
2547 Literal SQL is especially useful for nesting parenthesized clauses in the
2548 main SQL query. Here is a first example :
2550 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2554 bar => \["IN ($sub_stmt)" => @sub_bind],
2559 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2560 WHERE c2 < ? AND c3 LIKE ?))";
2561 @bind = (1234, 100, "foo%");
2563 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2564 are expressed in the same way. Of course the C<$sub_stmt> and
2565 its associated bind values can be generated through a former call
2568 my ($sub_stmt, @sub_bind)
2569 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2570 c3 => {-like => "foo%"}});
2573 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2576 In the examples above, the subquery was used as an operator on a column;
2577 but the same principle also applies for a clause within the main C<%where>
2578 hash, like an EXISTS subquery :
2580 my ($sub_stmt, @sub_bind)
2581 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2582 my %where = ( -and => [
2584 \["EXISTS ($sub_stmt)" => @sub_bind],
2589 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2590 WHERE c1 = ? AND c2 > t0.c0))";
2594 Observe that the condition on C<c2> in the subquery refers to
2595 column C<t0.c0> of the main query : this is I<not> a bind
2596 value, so we have to express it through a scalar ref.
2597 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2598 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2599 what we wanted here.
2601 Finally, here is an example where a subquery is used
2602 for expressing unary negation:
2604 my ($sub_stmt, @sub_bind)
2605 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2606 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2608 lname => {like => '%son%'},
2609 \["NOT ($sub_stmt)" => @sub_bind],
2614 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2615 @bind = ('%son%', 10, 20)
2617 =head3 Deprecated usage of Literal SQL
2619 Below are some examples of archaic use of literal SQL. It is shown only as
2620 reference for those who deal with legacy code. Each example has a much
2621 better, cleaner and safer alternative that users should opt for in new code.
2627 my %where = ( requestor => \'IS NOT NULL' )
2629 $stmt = "WHERE requestor IS NOT NULL"
2631 This used to be the way of generating NULL comparisons, before the handling
2632 of C<undef> got formalized. For new code please use the superior syntax as
2633 described in L</Tests for NULL values>.
2637 my %where = ( requestor => \'= submitter' )
2639 $stmt = "WHERE requestor = submitter"
2641 This used to be the only way to compare columns. Use the superior L</-ident>
2642 method for all new code. For example an identifier declared in such a way
2643 will be properly quoted if L</quote_char> is properly set, while the legacy
2644 form will remain as supplied.
2648 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2650 $stmt = "WHERE completed > ? AND is_ready"
2651 @bind = ('2012-12-21')
2653 Using an empty string literal used to be the only way to express a boolean.
2654 For all new code please use the much more readable
2655 L<-bool|/Unary operators: bool> operator.
2661 These pages could go on for a while, since the nesting of the data
2662 structures this module can handle are pretty much unlimited (the
2663 module implements the C<WHERE> expansion as a recursive function
2664 internally). Your best bet is to "play around" with the module a
2665 little to see how the data structures behave, and choose the best
2666 format for your data based on that.
2668 And of course, all the values above will probably be replaced with
2669 variables gotten from forms or the command line. After all, if you
2670 knew everything ahead of time, you wouldn't have to worry about
2671 dynamically-generating SQL and could just hardwire it into your
2674 =head1 ORDER BY CLAUSES
2676 Some functions take an order by clause. This can either be a scalar (just a
2677 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2678 or an array of either of the two previous forms. Examples:
2680 Given | Will Generate
2681 ----------------------------------------------------------
2683 \'colA DESC' | ORDER BY colA DESC
2685 'colA' | ORDER BY colA
2687 [qw/colA colB/] | ORDER BY colA, colB
2689 {-asc => 'colA'} | ORDER BY colA ASC
2691 {-desc => 'colB'} | ORDER BY colB DESC
2693 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2695 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2698 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2699 { -desc => [qw/colB/], | colC ASC, colD ASC
2700 { -asc => [qw/colC colD/],|
2702 ===========================================================
2706 =head1 SPECIAL OPERATORS
2708 my $sqlmaker = SQL::Abstract->new(special_ops => [
2712 my ($self, $field, $op, $arg) = @_;
2718 handler => 'method_name',
2722 A "special operator" is a SQL syntactic clause that can be
2723 applied to a field, instead of a usual binary operator.
2726 WHERE field IN (?, ?, ?)
2727 WHERE field BETWEEN ? AND ?
2728 WHERE MATCH(field) AGAINST (?, ?)
2730 Special operators IN and BETWEEN are fairly standard and therefore
2731 are builtin within C<SQL::Abstract> (as the overridable methods
2732 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2733 like the MATCH .. AGAINST example above which is specific to MySQL,
2734 you can write your own operator handlers - supply a C<special_ops>
2735 argument to the C<new> method. That argument takes an arrayref of
2736 operator definitions; each operator definition is a hashref with two
2743 the regular expression to match the operator
2747 Either a coderef or a plain scalar method name. In both cases
2748 the expected return is C<< ($sql, @bind) >>.
2750 When supplied with a method name, it is simply called on the
2751 L<SQL::Abstract/> object as:
2753 $self->$method_name ($field, $op, $arg)
2757 $op is the part that matched the handler regex
2758 $field is the LHS of the operator
2761 When supplied with a coderef, it is called as:
2763 $coderef->($self, $field, $op, $arg)
2768 For example, here is an implementation
2769 of the MATCH .. AGAINST syntax for MySQL
2771 my $sqlmaker = SQL::Abstract->new(special_ops => [
2773 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2774 {regex => qr/^match$/i,
2776 my ($self, $field, $op, $arg) = @_;
2777 $arg = [$arg] if not ref $arg;
2778 my $label = $self->_quote($field);
2779 my ($placeholder) = $self->_convert('?');
2780 my $placeholders = join ", ", (($placeholder) x @$arg);
2781 my $sql = $self->_sqlcase('match') . " ($label) "
2782 . $self->_sqlcase('against') . " ($placeholders) ";
2783 my @bind = $self->_bindtype($field, @$arg);
2784 return ($sql, @bind);
2791 =head1 UNARY OPERATORS
2793 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2797 my ($self, $op, $arg) = @_;
2803 handler => 'method_name',
2807 A "unary operator" is a SQL syntactic clause that can be
2808 applied to a field - the operator goes before the field
2810 You can write your own operator handlers - supply a C<unary_ops>
2811 argument to the C<new> method. That argument takes an arrayref of
2812 operator definitions; each operator definition is a hashref with two
2819 the regular expression to match the operator
2823 Either a coderef or a plain scalar method name. In both cases
2824 the expected return is C<< $sql >>.
2826 When supplied with a method name, it is simply called on the
2827 L<SQL::Abstract/> object as:
2829 $self->$method_name ($op, $arg)
2833 $op is the part that matched the handler regex
2834 $arg is the RHS or argument of the operator
2836 When supplied with a coderef, it is called as:
2838 $coderef->($self, $op, $arg)
2846 Thanks to some benchmarking by Mark Stosberg, it turns out that
2847 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2848 I must admit this wasn't an intentional design issue, but it's a
2849 byproduct of the fact that you get to control your C<DBI> handles
2852 To maximize performance, use a code snippet like the following:
2854 # prepare a statement handle using the first row
2855 # and then reuse it for the rest of the rows
2857 for my $href (@array_of_hashrefs) {
2858 $stmt ||= $sql->insert('table', $href);
2859 $sth ||= $dbh->prepare($stmt);
2860 $sth->execute($sql->values($href));
2863 The reason this works is because the keys in your C<$href> are sorted
2864 internally by B<SQL::Abstract>. Thus, as long as your data retains
2865 the same structure, you only have to generate the SQL the first time
2866 around. On subsequent queries, simply use the C<values> function provided
2867 by this module to return your values in the correct order.
2869 However this depends on the values having the same type - if, for
2870 example, the values of a where clause may either have values
2871 (resulting in sql of the form C<column = ?> with a single bind
2872 value), or alternatively the values might be C<undef> (resulting in
2873 sql of the form C<column IS NULL> with no bind value) then the
2874 caching technique suggested will not work.
2878 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2879 really like this part (I do, at least). Building up a complex query
2880 can be as simple as the following:
2887 use CGI::FormBuilder;
2890 my $form = CGI::FormBuilder->new(...);
2891 my $sql = SQL::Abstract->new;
2893 if ($form->submitted) {
2894 my $field = $form->field;
2895 my $id = delete $field->{id};
2896 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2899 Of course, you would still have to connect using C<DBI> to run the
2900 query, but the point is that if you make your form look like your
2901 table, the actual query script can be extremely simplistic.
2903 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2904 a fast interface to returning and formatting data. I frequently
2905 use these three modules together to write complex database query
2906 apps in under 50 lines.
2912 =item * gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
2914 =item * git: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
2920 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2921 Great care has been taken to preserve the I<published> behavior
2922 documented in previous versions in the 1.* family; however,
2923 some features that were previously undocumented, or behaved
2924 differently from the documentation, had to be changed in order
2925 to clarify the semantics. Hence, client code that was relying
2926 on some dark areas of C<SQL::Abstract> v1.*
2927 B<might behave differently> in v1.50.
2929 The main changes are :
2935 support for literal SQL through the C<< \ [$sql, bind] >> syntax.
2939 support for the { operator => \"..." } construct (to embed literal SQL)
2943 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2947 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2951 defensive programming : check arguments
2955 fixed bug with global logic, which was previously implemented
2956 through global variables yielding side-effects. Prior versions would
2957 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2958 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2959 Now this is interpreted
2960 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2965 fixed semantics of _bindtype on array args
2969 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2970 we just avoid shifting arrays within that tree.
2974 dropped the C<_modlogic> function
2978 =head1 ACKNOWLEDGEMENTS
2980 There are a number of individuals that have really helped out with
2981 this module. Unfortunately, most of them submitted bugs via CPAN
2982 so I have no idea who they are! But the people I do know are:
2984 Ash Berlin (order_by hash term support)
2985 Matt Trout (DBIx::Class support)
2986 Mark Stosberg (benchmarking)
2987 Chas Owens (initial "IN" operator support)
2988 Philip Collins (per-field SQL functions)
2989 Eric Kolve (hashref "AND" support)
2990 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2991 Dan Kubb (support for "quote_char" and "name_sep")
2992 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2993 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2994 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2995 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2996 Oliver Charles (support for "RETURNING" after "INSERT")
3002 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3006 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3008 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3010 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3011 While not an official support venue, C<DBIx::Class> makes heavy use of
3012 C<SQL::Abstract>, and as such list members there are very familiar with
3013 how to create queries.
3017 This module is free software; you may copy this under the same
3018 terms as perl itself (either the GNU General Public License or
3019 the Artistic License)