1 package SQL::Abstract; # see doc at end of file
3 # LDNOTE : this code is heavy refactoring from original SQLA.
4 # Several design decisions will need discussion during
5 # the test / diffusion / acceptance phase; those are marked with flag
6 # 'LDNOTE' (note by laurent.dami AT free.fr)
14 #======================================================================
16 #======================================================================
18 our $VERSION = '1.72';
20 # This would confuse some packagers
21 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
25 # special operators (-in, -between). May be extended/overridden by user.
26 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
27 my @BUILTIN_SPECIAL_OPS = (
28 {regex => qr/^ (?: not \s )? between $/ix, handler => '_where_field_BETWEEN'},
29 {regex => qr/^ (?: not \s )? in $/ix, handler => '_where_field_IN'},
30 {regex => qr/^ func $/ix, handler => '_where_field_FUNC'},
33 # unaryish operators - key maps to handler
34 my @BUILTIN_UNARY_OPS = (
35 # the digits are backcompat stuff
36 { regex => qr/^ and (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
37 { regex => qr/^ or (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
38 { regex => qr/^ nest (?: [_\s]? \d+ )? $/xi, handler => '_where_op_NEST' },
39 { regex => qr/^ (?: not \s )? bool $/xi, handler => '_where_op_BOOL' },
40 { regex => qr/^ func $/ix, handler => '_where_op_FUNC' },
43 #======================================================================
44 # DEBUGGING AND ERROR REPORTING
45 #======================================================================
48 return unless $_[0]->{debug}; shift; # a little faster
49 my $func = (caller(1))[3];
50 warn "[$func] ", @_, "\n";
54 my($func) = (caller(1))[3];
55 carp "[$func] Warning: ", @_;
59 my($func) = (caller(1))[3];
60 croak "[$func] Fatal: ", @_;
64 #======================================================================
66 #======================================================================
70 my $class = ref($self) || $self;
71 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
73 # choose our case by keeping an option around
74 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
76 # default logic for interpreting arrayrefs
77 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
79 # how to return bind vars
80 # LDNOTE: changed nwiger code : why this 'delete' ??
81 # $opt{bindtype} ||= delete($opt{bind_type}) || 'normal';
82 $opt{bindtype} ||= 'normal';
84 # default comparison is "=", but can be overridden
87 # try to recognize which are the 'equality' and 'unequality' ops
88 # (temporary quickfix, should go through a more seasoned API)
89 $opt{equality_op} = qr/^(\Q$opt{cmp}\E|is|(is\s+)?like)$/i;
90 $opt{inequality_op} = qr/^(!=|<>|(is\s+)?not(\s+like)?)$/i;
93 $opt{sqltrue} ||= '1=1';
94 $opt{sqlfalse} ||= '0=1';
97 $opt{special_ops} ||= [];
98 # regexes are applied in order, thus push after user-defines
99 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
102 $opt{unary_ops} ||= [];
103 push @{$opt{unary_ops}}, @BUILTIN_UNARY_OPS;
105 # rudimentary saniy-check for user supplied bits treated as functions/operators
106 # If a purported function matches this regular expression, an exception is thrown.
107 # Literal SQL is *NOT* subject to this check, only functions (and column names
108 # when quoting is not in effect)
111 # need to guard against ()'s in column names too, but this will break tons of
112 # hacks... ideas anyone?
113 $opt{injection_guard} ||= qr/
119 return bless \%opt, $class;
123 sub _assert_pass_injection_guard {
124 if ($_[1] =~ $_[0]->{injection_guard}) {
125 my $class = ref $_[0];
126 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
127 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
128 . "{injection_guard} attribute to ${class}->new()"
133 #======================================================================
135 #======================================================================
139 my $table = $self->_table(shift);
140 my $data = shift || return;
143 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
144 my ($sql, @bind) = $self->$method($data);
145 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
147 if ($options->{returning}) {
148 my ($s, @b) = $self->_insert_returning ($options);
153 return wantarray ? ($sql, @bind) : $sql;
156 sub _insert_returning {
157 my ($self, $options) = @_;
159 my $f = $options->{returning};
161 my $fieldlist = $self->_SWITCH_refkind($f, {
162 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
163 SCALAR => sub {$self->_quote($f)},
164 SCALARREF => sub {$$f},
166 return $self->_sqlcase(' returning ') . $fieldlist;
169 sub _insert_HASHREF { # explicit list of fields and then values
170 my ($self, $data) = @_;
172 my @fields = sort keys %$data;
174 my ($sql, @bind) = $self->_insert_values($data);
177 $_ = $self->_quote($_) foreach @fields;
178 $sql = "( ".join(", ", @fields).") ".$sql;
180 return ($sql, @bind);
183 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
184 my ($self, $data) = @_;
186 # no names (arrayref) so can't generate bindtype
187 $self->{bindtype} ne 'columns'
188 or belch "can't do 'columns' bindtype when called with arrayref";
190 # fold the list of values into a hash of column name - value pairs
191 # (where the column names are artificially generated, and their
192 # lexicographical ordering keep the ordering of the original list)
193 my $i = "a"; # incremented values will be in lexicographical order
194 my $data_in_hash = { map { ($i++ => $_) } @$data };
196 return $self->_insert_values($data_in_hash);
199 sub _insert_ARRAYREFREF { # literal SQL with bind
200 my ($self, $data) = @_;
202 my ($sql, @bind) = @${$data};
203 $self->_assert_bindval_matches_bindtype(@bind);
205 return ($sql, @bind);
209 sub _insert_SCALARREF { # literal SQL without bind
210 my ($self, $data) = @_;
216 my ($self, $data) = @_;
218 my (@values, @all_bind);
219 foreach my $column (sort keys %$data) {
220 my $v = $data->{$column};
222 $self->_SWITCH_refkind($v, {
225 if ($self->{array_datatypes}) { # if array datatype are activated
227 push @all_bind, $self->_bindtype($column, $v);
229 else { # else literal SQL with bind
230 my ($sql, @bind) = @$v;
231 $self->_assert_bindval_matches_bindtype(@bind);
233 push @all_bind, @bind;
237 ARRAYREFREF => sub { # literal SQL with bind
238 my ($sql, @bind) = @${$v};
239 $self->_assert_bindval_matches_bindtype(@bind);
241 push @all_bind, @bind;
244 # THINK : anything useful to do with a HASHREF ?
245 HASHREF => sub { # (nothing, but old SQLA passed it through)
246 #TODO in SQLA >= 2.0 it will die instead
247 belch "HASH ref as bind value in insert is not supported";
249 push @all_bind, $self->_bindtype($column, $v);
252 SCALARREF => sub { # literal SQL without bind
256 SCALAR_or_UNDEF => sub {
258 push @all_bind, $self->_bindtype($column, $v);
265 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
266 return ($sql, @all_bind);
271 #======================================================================
273 #======================================================================
278 my $table = $self->_table(shift);
279 my $data = shift || return;
282 # first build the 'SET' part of the sql statement
283 my (@set, @all_bind);
284 puke "Unsupported data type specified to \$sql->update"
285 unless ref $data eq 'HASH';
287 for my $k (sort keys %$data) {
290 my $label = $self->_quote($k);
292 $self->_SWITCH_refkind($v, {
294 if ($self->{array_datatypes}) { # array datatype
295 push @set, "$label = ?";
296 push @all_bind, $self->_bindtype($k, $v);
298 else { # literal SQL with bind
299 my ($sql, @bind) = @$v;
300 $self->_assert_bindval_matches_bindtype(@bind);
301 push @set, "$label = $sql";
302 push @all_bind, @bind;
305 ARRAYREFREF => sub { # literal SQL with bind
306 my ($sql, @bind) = @${$v};
307 $self->_assert_bindval_matches_bindtype(@bind);
308 push @set, "$label = $sql";
309 push @all_bind, @bind;
311 SCALARREF => sub { # literal SQL without bind
312 push @set, "$label = $$v";
315 my ($op, $arg, @rest) = %$v;
317 puke 'Operator calls in update must be in the form { -op => $arg }'
318 if (@rest or not $op =~ /^\-(.+)/);
320 local $self->{_nested_func_lhs} = $k;
321 my ($sql, @bind) = $self->_where_unary_op ($1, $arg);
323 push @set, "$label = $sql";
324 push @all_bind, @bind;
326 SCALAR_or_UNDEF => sub {
327 push @set, "$label = ?";
328 push @all_bind, $self->_bindtype($k, $v);
334 my $sql = $self->_sqlcase('update') . " $table " . $self->_sqlcase('set ')
338 my($where_sql, @where_bind) = $self->where($where);
340 push @all_bind, @where_bind;
343 return wantarray ? ($sql, @all_bind) : $sql;
349 #======================================================================
351 #======================================================================
356 my $table = $self->_table(shift);
357 my $fields = shift || '*';
361 my($where_sql, @bind) = $self->where($where, $order);
363 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
365 my $sql = join(' ', $self->_sqlcase('select'), $f,
366 $self->_sqlcase('from'), $table)
369 return wantarray ? ($sql, @bind) : $sql;
372 #======================================================================
374 #======================================================================
379 my $table = $self->_table(shift);
383 my($where_sql, @bind) = $self->where($where);
384 my $sql = $self->_sqlcase('delete from') . " $table" . $where_sql;
386 return wantarray ? ($sql, @bind) : $sql;
390 #======================================================================
392 #======================================================================
396 # Finally, a separate routine just to handle WHERE clauses
398 my ($self, $where, $order) = @_;
401 my ($sql, @bind) = $self->_recurse_where($where);
402 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
406 $sql .= $self->_order_by($order);
409 return wantarray ? ($sql, @bind) : $sql;
414 my ($self, $where, $logic) = @_;
416 # dispatch on appropriate method according to refkind of $where
417 my $method = $self->_METHOD_FOR_refkind("_where", $where);
419 my ($sql, @bind) = $self->$method($where, $logic);
421 # DBIx::Class directly calls _recurse_where in scalar context, so
422 # we must implement it, even if not in the official API
423 return wantarray ? ($sql, @bind) : $sql;
428 #======================================================================
429 # WHERE: top-level ARRAYREF
430 #======================================================================
433 sub _where_ARRAYREF {
434 my ($self, $where, $logic) = @_;
436 $logic = uc($logic || $self->{logic});
437 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
439 my @clauses = @$where;
441 my (@sql_clauses, @all_bind);
442 # need to use while() so can shift() for pairs
443 while (my $el = shift @clauses) {
445 # switch according to kind of $el and get corresponding ($sql, @bind)
446 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
448 # skip empty elements, otherwise get invalid trailing AND stuff
449 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
453 $self->_assert_bindval_matches_bindtype(@b);
457 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
458 # LDNOTE : previous SQLA code for hashrefs was creating a dirty
459 # side-effect: the first hashref within an array would change
460 # the global logic to 'AND'. So [ {cond1, cond2}, [cond3, cond4] ]
461 # was interpreted as "(cond1 AND cond2) OR (cond3 AND cond4)",
462 # whereas it should be "(cond1 AND cond2) OR (cond3 OR cond4)".
464 SCALARREF => sub { ($$el); },
466 SCALAR => sub {# top-level arrayref with scalars, recurse in pairs
467 $self->_recurse_where({$el => shift(@clauses)})},
469 UNDEF => sub {puke "not supported : UNDEF in arrayref" },
473 push @sql_clauses, $sql;
474 push @all_bind, @bind;
478 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
481 #======================================================================
482 # WHERE: top-level ARRAYREFREF
483 #======================================================================
485 sub _where_ARRAYREFREF {
486 my ($self, $where) = @_;
487 my ($sql, @bind) = @$$where;
488 $self->_assert_bindval_matches_bindtype(@bind);
489 return ($sql, @bind);
492 #======================================================================
493 # WHERE: top-level HASHREF
494 #======================================================================
497 my ($self, $where) = @_;
498 my (@sql_clauses, @all_bind);
500 for my $k (sort keys %$where) {
501 my $v = $where->{$k};
503 # ($k => $v) is either a special unary op or a regular hashpair
504 my ($sql, @bind) = do {
506 # put the operator in canonical form
508 $op = substr $op, 1; # remove initial dash
509 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
510 $op =~ s/\s+/ /g; # compress whitespace
512 # so that -not_foo works correctly
513 $op =~ s/^not_/NOT /i;
515 $self->_debug("Unary OP(-$op) within hashref, recursing...");
516 my ($s, @b) = $self->_where_unary_op ($op, $v);
518 # top level vs nested
519 # we assume that handled unary ops will take care of their ()s
521 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
523 defined($self->{_nested_func_lhs}) && ($self->{_nested_func_lhs} eq $k)
528 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
529 $self->$method($k, $v);
533 push @sql_clauses, $sql;
534 push @all_bind, @bind;
537 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
540 sub _where_unary_op {
541 my ($self, $op, $rhs) = @_;
543 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
544 my $handler = $op_entry->{handler};
546 if (not ref $handler) {
547 if ($op =~ s/ [_\s]? \d+ $//x ) {
548 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
549 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
551 return $self->$handler ($op, $rhs);
553 elsif (ref $handler eq 'CODE') {
554 return $handler->($self, $op, $rhs);
557 puke "Illegal handler for operator $op - expecting a method name or a coderef";
561 $self->debug("Generic unary OP: $op - recursing as function");
563 $self->_assert_pass_injection_guard($op);
565 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
567 puke "Illegal use of top-level '$op'"
568 unless $self->{_nested_func_lhs};
571 $self->_convert('?'),
572 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
576 $self->_recurse_where ($rhs)
580 $sql = sprintf ('%s %s',
581 $self->_sqlcase($op),
585 return ($sql, @bind);
588 sub _where_op_ANDOR {
589 my ($self, $op, $v) = @_;
591 $self->_SWITCH_refkind($v, {
593 return $self->_where_ARRAYREF($v, $op);
597 return ( $op =~ /^or/i )
598 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
599 : $self->_where_HASHREF($v);
603 puke "-$op => \\\$scalar makes little sense, use " .
605 ? '[ \$scalar, \%rest_of_conditions ] instead'
606 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
611 puke "-$op => \\[...] makes little sense, use " .
613 ? '[ \[...], \%rest_of_conditions ] instead'
614 : '-and => [ \[...], \%rest_of_conditions ] instead'
618 SCALAR => sub { # permissively interpreted as SQL
619 puke "-$op => \$value makes little sense, use -bool => \$value instead";
623 puke "-$op => undef not supported";
629 my ($self, $op, $v) = @_;
631 $self->_SWITCH_refkind($v, {
633 SCALAR => sub { # permissively interpreted as SQL
634 belch "literal SQL should be -nest => \\'scalar' "
635 . "instead of -nest => 'scalar' ";
640 puke "-$op => undef not supported";
644 $self->_recurse_where ($v);
652 my ($self, $op, $v) = @_;
654 my ($s, @b) = $self->_SWITCH_refkind($v, {
655 SCALAR => sub { # interpreted as SQL column
656 $self->_convert($self->_quote($v));
660 puke "-$op => undef not supported";
664 $self->_recurse_where ($v);
668 $s = "(NOT $s)" if $op =~ /^not/i;
673 sub _where_hashpair_ARRAYREF {
674 my ($self, $k, $v) = @_;
677 my @v = @$v; # need copy because of shift below
678 $self->_debug("ARRAY($k) means distribute over elements");
680 # put apart first element if it is an operator (-and, -or)
682 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
686 my @distributed = map { {$k => $_} } @v;
689 $self->_debug("OP($op) reinjected into the distributed array");
690 unshift @distributed, $op;
693 my $logic = $op ? substr($op, 1) : '';
695 return $self->_recurse_where(\@distributed, $logic);
698 # LDNOTE : not sure of this one. What does "distribute over nothing" mean?
699 $self->_debug("empty ARRAY($k) means 0=1");
700 return ($self->{sqlfalse});
704 sub _where_hashpair_HASHREF {
705 my ($self, $k, $v, $logic) = @_;
708 local $self->{_nested_func_lhs} = $self->{_nested_func_lhs};
710 my ($all_sql, @all_bind);
712 for my $orig_op (sort keys %$v) {
713 my $val = $v->{$orig_op};
715 # put the operator in canonical form
718 # FIXME - we need to phase out dash-less ops
719 $op =~ s/^-//; # remove possible initial dash
720 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
721 $op =~ s/\s+/ /g; # compress whitespace
723 $self->_assert_pass_injection_guard($op);
725 # so that -not_foo works correctly
726 $op =~ s/^not_/NOT /i;
730 # CASE: col-value logic modifiers
731 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
732 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
734 # CASE: special operators like -in or -between
735 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
736 my $handler = $special_op->{handler};
738 puke "No handler supplied for special operator $orig_op";
740 elsif (not ref $handler) {
741 ($sql, @bind) = $self->$handler ($k, $op, $val);
743 elsif (ref $handler eq 'CODE') {
744 ($sql, @bind) = $handler->($self, $k, $op, $val);
747 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
751 $self->_SWITCH_refkind($val, {
753 ARRAYREF => sub { # CASE: col => {op => \@vals}
754 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
757 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
758 my ($sub_sql, @sub_bind) = @$$val;
759 $self->_assert_bindval_matches_bindtype(@sub_bind);
760 $sql = join ' ', $self->_convert($self->_quote($k)),
761 $self->_sqlcase($op),
766 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
767 my $is = ($op =~ $self->{equality_op}) ? 'is' :
768 ($op =~ $self->{inequality_op}) ? 'is not' :
769 puke "unexpected operator '$orig_op' with undef operand";
770 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
773 FALLBACK => sub { # CASE: col => {op/func => $stuff}
775 # retain for proper column type bind
776 $self->{_nested_func_lhs} ||= $k;
778 ($sql, @bind) = $self->_where_unary_op ($op, $val);
781 $self->_convert($self->_quote($k)),
782 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
788 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
789 push @all_bind, @bind;
791 return ($all_sql, @all_bind);
796 sub _where_field_op_ARRAYREF {
797 my ($self, $k, $op, $vals) = @_;
799 my @vals = @$vals; #always work on a copy
802 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
804 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
807 # see if the first element is an -and/-or op
809 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
814 # distribute $op over each remaining member of @vals, append logic if exists
815 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
817 # LDNOTE : had planned to change the distribution logic when
818 # $op =~ $self->{inequality_op}, because of Morgan laws :
819 # with {field => {'!=' => [22, 33]}}, it would be ridiculous to generate
820 # WHERE field != 22 OR field != 33 : the user probably means
821 # WHERE field != 22 AND field != 33.
822 # To do this, replace the above to roughly :
823 # my $logic = ($op =~ $self->{inequality_op}) ? 'AND' : 'OR';
824 # return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
828 # try to DWIM on equality operators
829 # LDNOTE : not 100% sure this is the correct thing to do ...
830 return ($self->{sqlfalse}) if $op =~ $self->{equality_op};
831 return ($self->{sqltrue}) if $op =~ $self->{inequality_op};
834 puke "operator '$op' applied on an empty array (field '$k')";
839 sub _where_hashpair_SCALARREF {
840 my ($self, $k, $v) = @_;
841 $self->_debug("SCALAR($k) means literal SQL: $$v");
842 my $sql = $self->_quote($k) . " " . $$v;
846 # literal SQL with bind
847 sub _where_hashpair_ARRAYREFREF {
848 my ($self, $k, $v) = @_;
849 $self->_debug("REF($k) means literal SQL: @${$v}");
850 my ($sql, @bind) = @$$v;
851 $self->_assert_bindval_matches_bindtype(@bind);
852 $sql = $self->_quote($k) . " " . $sql;
853 return ($sql, @bind );
856 # literal SQL without bind
857 sub _where_hashpair_SCALAR {
858 my ($self, $k, $v) = @_;
859 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
860 my $sql = join ' ', $self->_convert($self->_quote($k)),
861 $self->_sqlcase($self->{cmp}),
862 $self->_convert('?');
863 my @bind = $self->_bindtype($k, $v);
864 return ( $sql, @bind);
868 sub _where_hashpair_UNDEF {
869 my ($self, $k, $v) = @_;
870 $self->_debug("UNDEF($k) means IS NULL");
871 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
875 #======================================================================
876 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
877 #======================================================================
880 sub _where_SCALARREF {
881 my ($self, $where) = @_;
884 $self->_debug("SCALAR(*top) means literal SQL: $$where");
890 my ($self, $where) = @_;
893 $self->_debug("NOREF(*top) means literal SQL: $where");
904 #======================================================================
905 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
906 #======================================================================
909 sub _where_field_BETWEEN {
910 my ($self, $k, $op, $vals) = @_;
912 my ($label, $and, $placeholder);
913 $label = $self->_convert($self->_quote($k));
914 $and = ' ' . $self->_sqlcase('and') . ' ';
915 $placeholder = $self->_convert('?');
916 $op = $self->_sqlcase($op);
918 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
920 my ($s, @b) = @$$vals;
921 $self->_assert_bindval_matches_bindtype(@b);
928 puke "special op 'between' accepts an arrayref with exactly two values"
931 my (@all_sql, @all_bind);
932 foreach my $val (@$vals) {
933 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
935 return ($placeholder, $self->_bindtype($k, $val) );
941 my ($sql, @bind) = @$$val;
942 $self->_assert_bindval_matches_bindtype(@bind);
943 return ($sql, @bind);
946 my ($func, $arg, @rest) = %$val;
947 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
948 if (@rest or $func !~ /^ \- (.+)/x);
949 local $self->{_nested_func_lhs} = $k;
950 $self->_where_unary_op ($1 => $arg);
954 push @all_bind, @bind;
958 (join $and, @all_sql),
963 puke "special op 'between' accepts an arrayref with two values, or a single literal scalarref/arrayref-ref";
967 my $sql = "( $label $op $clause )";
971 sub _where_field_FUNC {
972 my ($self, $k, $op, $vals) = @_;
974 return $self->_where_generic_FUNC($k,$vals);
978 my ($self, $k, $vals) = @_;
980 return $self->_where_generic_FUNC('', $vals);
983 sub _where_generic_FUNC {
984 my ($self, $k, $vals) = @_;
986 my $label = $self->_convert($self->_quote($k));
987 my $placeholder = $self->_convert('?');
988 my $error = "special op 'func' accepts an arrayref with more than one value.";
990 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
992 my ($s, @b) = @$$vals;
993 $self->_assert_bindval_matches_bindtype(@b);
1003 my (@all_sql, @all_bind);
1005 my ($func,@rest_of_vals) = @$vals;
1009 puke "Function in -func may only contain alphanumeric characters.";
1012 foreach my $val (@rest_of_vals) {
1013 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1015 return ($placeholder, $self->_bindtype($k, $val) );
1020 ARRAYREFREF => sub {
1021 my ($sql, @bind) = @$$val;
1022 $self->_assert_bindval_matches_bindtype(@bind);
1023 return ($sql, @bind);
1026 my ($func, $arg, @rest) = %$val;
1027 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1028 if (@rest or $func !~ /^ \- (.+)/x);
1029 local $self->{_nested_func_lhs} = $k;
1030 $self->_where_unary_op ($1 => $arg);
1033 push @all_sql, $sql;
1034 push @all_bind, @bind;
1038 ("$func(" . (join ",", @all_sql) . ")"),
1047 my $sql = $k ? "( $label = $clause )" : "( $clause )";
1048 return ($sql, @bind)
1051 sub _where_field_IN {
1052 my ($self, $k, $op, $vals) = @_;
1054 # backwards compatibility : if scalar, force into an arrayref
1055 $vals = [$vals] if defined $vals && ! ref $vals;
1057 my ($label) = $self->_convert($self->_quote($k));
1058 my ($placeholder) = $self->_convert('?');
1059 $op = $self->_sqlcase($op);
1061 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1062 ARRAYREF => sub { # list of choices
1063 if (@$vals) { # nonempty list
1064 my (@all_sql, @all_bind);
1066 for my $val (@$vals) {
1067 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1069 return ($placeholder, $val);
1074 ARRAYREFREF => sub {
1075 my ($sql, @bind) = @$$val;
1076 $self->_assert_bindval_matches_bindtype(@bind);
1077 return ($sql, @bind);
1080 my ($func, $arg, @rest) = %$val;
1081 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1082 if (@rest or $func !~ /^ \- (.+)/x);
1083 local $self->{_nested_func_lhs} = $k;
1084 $self->_where_unary_op ($1 => $arg);
1087 return $self->_sqlcase('null');
1090 push @all_sql, $sql;
1091 push @all_bind, @bind;
1095 sprintf ('%s %s ( %s )',
1098 join (', ', @all_sql)
1100 $self->_bindtype($k, @all_bind),
1103 else { # empty list : some databases won't understand "IN ()", so DWIM
1104 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1109 SCALARREF => sub { # literal SQL
1110 my $sql = $self->_open_outer_paren ($$vals);
1111 return ("$label $op ( $sql )");
1113 ARRAYREFREF => sub { # literal SQL with bind
1114 my ($sql, @bind) = @$$vals;
1115 $self->_assert_bindval_matches_bindtype(@bind);
1116 $sql = $self->_open_outer_paren ($sql);
1117 return ("$label $op ( $sql )", @bind);
1121 puke "special op 'in' requires an arrayref (or scalarref/arrayref-ref)";
1125 return ($sql, @bind);
1128 # Some databases (SQLite) treat col IN (1, 2) different from
1129 # col IN ( (1, 2) ). Use this to strip all outer parens while
1130 # adding them back in the corresponding method
1131 sub _open_outer_paren {
1132 my ($self, $sql) = @_;
1133 $sql = $1 while $sql =~ /^ \s* \( (.*) \) \s* $/xs;
1138 #======================================================================
1140 #======================================================================
1143 my ($self, $arg) = @_;
1146 for my $c ($self->_order_by_chunks ($arg) ) {
1147 $self->_SWITCH_refkind ($c, {
1148 SCALAR => sub { push @sql, $c },
1149 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1155 $self->_sqlcase(' order by'),
1161 return wantarray ? ($sql, @bind) : $sql;
1164 sub _order_by_chunks {
1165 my ($self, $arg) = @_;
1167 return $self->_SWITCH_refkind($arg, {
1170 map { $self->_order_by_chunks ($_ ) } @$arg;
1173 ARRAYREFREF => sub {
1174 my ($s, @b) = @$$arg;
1175 $self->_assert_bindval_matches_bindtype(@b);
1179 SCALAR => sub {$self->_quote($arg)},
1181 UNDEF => sub {return () },
1183 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1186 # get first pair in hash
1187 my ($key, $val, @rest) = %$arg;
1189 return () unless $key;
1191 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1192 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1198 for my $c ($self->_order_by_chunks ($val)) {
1201 $self->_SWITCH_refkind ($c, {
1206 ($sql, @bind) = @$c;
1210 $sql = $sql . ' ' . $self->_sqlcase($direction);
1212 push @ret, [ $sql, @bind];
1221 #======================================================================
1222 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1223 #======================================================================
1228 $self->_SWITCH_refkind($from, {
1229 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1230 SCALAR => sub {$self->_quote($from)},
1231 SCALARREF => sub {$$from},
1232 ARRAYREFREF => sub {join ', ', @$from;},
1237 #======================================================================
1239 #======================================================================
1241 # highly optimized, as it's called way too often
1243 # my ($self, $label) = @_;
1245 return '' unless defined $_[1];
1246 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1248 unless ($_[0]->{quote_char}) {
1249 $_[0]->_assert_pass_injection_guard($_[1]);
1253 my $qref = ref $_[0]->{quote_char};
1256 ($l, $r) = ( $_[0]->{quote_char}, $_[0]->{quote_char} );
1258 elsif ($qref eq 'ARRAY') {
1259 ($l, $r) = @{$_[0]->{quote_char}};
1262 puke "Unsupported quote_char format: $_[0]->{quote_char}";
1265 # parts containing * are naturally unquoted
1266 return join( $_[0]->{name_sep}||'', map
1267 { $_ eq '*' ? $_ : $l . $_ . $r }
1268 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1273 # Conversion, if applicable
1275 #my ($self, $arg) = @_;
1277 # LDNOTE : modified the previous implementation below because
1278 # it was not consistent : the first "return" is always an array,
1279 # the second "return" is context-dependent. Anyway, _convert
1280 # seems always used with just a single argument, so make it a
1282 # return @_ unless $self->{convert};
1283 # my $conv = $self->_sqlcase($self->{convert});
1284 # my @ret = map { $conv.'('.$_.')' } @_;
1285 # return wantarray ? @ret : $ret[0];
1286 if ($_[0]->{convert}) {
1287 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1294 #my ($self, $col, @vals) = @_;
1296 #LDNOTE : changed original implementation below because it did not make
1297 # sense when bindtype eq 'columns' and @vals > 1.
1298 # return $self->{bindtype} eq 'columns' ? [ $col, @vals ] : @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) = $sql->select($table, \@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 comparsion 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 separates a table and column name. It is
1870 necessary to specify this when the C<quote_char> option is selected,
1871 so that tables and column names can be individually quoted like this:
1873 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1875 =item injection_guard
1877 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1878 column name specified in a query structure. This is a safety mechanism to avoid
1879 injection attacks when mishandling user input e.g.:
1881 my %condition_as_column_value_pairs = get_values_from_user();
1882 $sqla->select( ... , \%condition_as_column_value_pairs );
1884 If the expression matches an exception is thrown. Note that literal SQL
1885 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1887 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1889 =item array_datatypes
1891 When this option is true, arrayrefs in INSERT or UPDATE are
1892 interpreted as array datatypes and are passed directly
1894 When this option is false, arrayrefs are interpreted
1895 as literal SQL, just like refs to arrayrefs
1896 (but this behavior is for backwards compatibility; when writing
1897 new queries, use the "reference to arrayref" syntax
1903 Takes a reference to a list of "special operators"
1904 to extend the syntax understood by L<SQL::Abstract>.
1905 See section L</"SPECIAL OPERATORS"> for details.
1909 Takes a reference to a list of "unary operators"
1910 to extend the syntax understood by L<SQL::Abstract>.
1911 See section L</"UNARY OPERATORS"> for details.
1917 =head2 insert($table, \@values || \%fieldvals, \%options)
1919 This is the simplest function. You simply give it a table name
1920 and either an arrayref of values or hashref of field/value pairs.
1921 It returns an SQL INSERT statement and a list of bind values.
1922 See the sections on L</"Inserting and Updating Arrays"> and
1923 L</"Inserting and Updating SQL"> for information on how to insert
1924 with those data types.
1926 The optional C<\%options> hash reference may contain additional
1927 options to generate the insert SQL. Currently supported options
1934 Takes either a scalar of raw SQL fields, or an array reference of
1935 field names, and adds on an SQL C<RETURNING> statement at the end.
1936 This allows you to return data generated by the insert statement
1937 (such as row IDs) without performing another C<SELECT> statement.
1938 Note, however, this is not part of the SQL standard and may not
1939 be supported by all database engines.
1943 =head2 update($table, \%fieldvals, \%where)
1945 This takes a table, hashref of field/value pairs, and an optional
1946 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
1948 See the sections on L</"Inserting and Updating Arrays"> and
1949 L</"Inserting and Updating SQL"> for information on how to insert
1950 with those data types.
1952 =head2 select($source, $fields, $where, $order)
1954 This returns a SQL SELECT statement and associated list of bind values, as
1955 specified by the arguments :
1961 Specification of the 'FROM' part of the statement.
1962 The argument can be either a plain scalar (interpreted as a table
1963 name, will be quoted), or an arrayref (interpreted as a list
1964 of table names, joined by commas, quoted), or a scalarref
1965 (literal table name, not quoted), or a ref to an arrayref
1966 (list of literal table names, joined by commas, not quoted).
1970 Specification of the list of fields to retrieve from
1972 The argument can be either an arrayref (interpreted as a list
1973 of field names, will be joined by commas and quoted), or a
1974 plain scalar (literal SQL, not quoted).
1975 Please observe that this API is not as flexible as for
1976 the first argument C<$table>, for backwards compatibility reasons.
1980 Optional argument to specify the WHERE part of the query.
1981 The argument is most often a hashref, but can also be
1982 an arrayref or plain scalar --
1983 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
1987 Optional argument to specify the ORDER BY part of the query.
1988 The argument can be a scalar, a hashref or an arrayref
1989 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
1995 =head2 delete($table, \%where)
1997 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
1998 It returns an SQL DELETE statement and list of bind values.
2000 =head2 where(\%where, \@order)
2002 This is used to generate just the WHERE clause. For example,
2003 if you have an arbitrary data structure and know what the
2004 rest of your SQL is going to look like, but want an easy way
2005 to produce a WHERE clause, use this. It returns an SQL WHERE
2006 clause and list of bind values.
2009 =head2 values(\%data)
2011 This just returns the values from the hash C<%data>, in the same
2012 order that would be returned from any of the other above queries.
2013 Using this allows you to markedly speed up your queries if you
2014 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2016 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2018 Warning: This is an experimental method and subject to change.
2020 This returns arbitrarily generated SQL. It's a really basic shortcut.
2021 It will return two different things, depending on return context:
2023 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2024 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2026 These would return the following:
2028 # First calling form
2029 $stmt = "CREATE TABLE test (?, ?)";
2030 @bind = (field1, field2);
2032 # Second calling form
2033 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2035 Depending on what you're trying to do, it's up to you to choose the correct
2036 format. In this example, the second form is what you would want.
2040 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2044 ALTER SESSION SET nls_date_format = 'MM/YY'
2046 You get the idea. Strings get their case twiddled, but everything
2047 else remains verbatim.
2052 =head1 WHERE CLAUSES
2056 This module uses a variation on the idea from L<DBIx::Abstract>. It
2057 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2058 module is that things in arrays are OR'ed, and things in hashes
2061 The easiest way to explain is to show lots of examples. After
2062 each C<%where> hash shown, it is assumed you used:
2064 my($stmt, @bind) = $sql->where(\%where);
2066 However, note that the C<%where> hash can be used directly in any
2067 of the other functions as well, as described above.
2069 =head2 Key-value pairs
2071 So, let's get started. To begin, a simple hash:
2075 status => 'completed'
2078 Is converted to SQL C<key = val> statements:
2080 $stmt = "WHERE user = ? AND status = ?";
2081 @bind = ('nwiger', 'completed');
2083 One common thing I end up doing is having a list of values that
2084 a field can be in. To do this, simply specify a list inside of
2089 status => ['assigned', 'in-progress', 'pending'];
2092 This simple code will create the following:
2094 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2095 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2097 A field associated to an empty arrayref will be considered a
2098 logical false and will generate 0=1.
2100 =head2 Tests for NULL values
2102 If the value part is C<undef> then this is converted to SQL <IS NULL>
2111 $stmt = "WHERE user = ? AND status IS NULL";
2114 =head2 Specific comparison operators
2116 If you want to specify a different type of operator for your comparison,
2117 you can use a hashref for a given column:
2121 status => { '!=', 'completed' }
2124 Which would generate:
2126 $stmt = "WHERE user = ? AND status != ?";
2127 @bind = ('nwiger', 'completed');
2129 To test against multiple values, just enclose the values in an arrayref:
2131 status => { '=', ['assigned', 'in-progress', 'pending'] };
2133 Which would give you:
2135 "WHERE status = ? OR status = ? OR status = ?"
2138 The hashref can also contain multiple pairs, in which case it is expanded
2139 into an C<AND> of its elements:
2143 status => { '!=', 'completed', -not_like => 'pending%' }
2146 # Or more dynamically, like from a form
2147 $where{user} = 'nwiger';
2148 $where{status}{'!='} = 'completed';
2149 $where{status}{'-not_like'} = 'pending%';
2151 # Both generate this
2152 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2153 @bind = ('nwiger', 'completed', 'pending%');
2156 To get an OR instead, you can combine it with the arrayref idea:
2160 priority => [ {'=', 2}, {'!=', 1} ]
2163 Which would generate:
2165 $stmt = "WHERE user = ? AND priority = ? OR priority != ?";
2166 @bind = ('nwiger', '2', '1');
2168 If you want to include literal SQL (with or without bind values), just use a
2169 scalar reference or array reference as the value:
2172 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2173 date_expires => { '<' => \"now()" }
2176 Which would generate:
2178 $stmt = "WHERE date_entered > "to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2179 @bind = ('11/26/2008');
2182 =head2 Logic and nesting operators
2184 In the example above,
2185 there is a subtle trap if you want to say something like
2186 this (notice the C<AND>):
2188 WHERE priority != ? AND priority != ?
2190 Because, in Perl you I<can't> do this:
2192 priority => { '!=', 2, '!=', 1 }
2194 As the second C<!=> key will obliterate the first. The solution
2195 is to use the special C<-modifier> form inside an arrayref:
2197 priority => [ -and => {'!=', 2},
2201 Normally, these would be joined by C<OR>, but the modifier tells it
2202 to use C<AND> instead. (Hint: You can use this in conjunction with the
2203 C<logic> option to C<new()> in order to change the way your queries
2204 work by default.) B<Important:> Note that the C<-modifier> goes
2205 B<INSIDE> the arrayref, as an extra first element. This will
2206 B<NOT> do what you think it might:
2208 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2210 Here is a quick list of equivalencies, since there is some overlap:
2213 status => {'!=', 'completed', 'not like', 'pending%' }
2214 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2217 status => {'=', ['assigned', 'in-progress']}
2218 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2219 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2223 =head2 Special operators : IN, BETWEEN, etc.
2225 You can also use the hashref format to compare a list of fields using the
2226 C<IN> comparison operator, by specifying the list as an arrayref:
2229 status => 'completed',
2230 reportid => { -in => [567, 2335, 2] }
2233 Which would generate:
2235 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2236 @bind = ('completed', '567', '2335', '2');
2238 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2241 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2242 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2243 'sqltrue' (by default : C<1=1>).
2245 In addition to the array you can supply a chunk of literal sql or
2246 literal sql with bind:
2249 customer => { -in => \[
2250 'SELECT cust_id FROM cust WHERE balance > ?',
2253 status => { -in => \'SELECT status_codes FROM states' },
2259 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2260 AND status IN ( SELECT status_codes FROM states )
2266 Another pair of operators is C<-between> and C<-not_between>,
2267 used with an arrayref of two values:
2271 completion_date => {
2272 -not_between => ['2002-10-01', '2003-02-06']
2278 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2280 Just like with C<-in> all plausible combinations of literal SQL
2284 start0 => { -between => [ 1, 2 ] },
2285 start1 => { -between => \["? AND ?", 1, 2] },
2286 start2 => { -between => \"lower(x) AND upper(y)" },
2287 start3 => { -between => [
2289 \["upper(?)", 'stuff' ],
2296 ( start0 BETWEEN ? AND ? )
2297 AND ( start1 BETWEEN ? AND ? )
2298 AND ( start2 BETWEEN lower(x) AND upper(y) )
2299 AND ( start3 BETWEEN lower(x) AND upper(?) )
2301 @bind = (1, 2, 1, 2, 'stuff');
2304 These are the two builtin "special operators"; but the
2305 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2307 Another operator is C<-func> that allows you to call SQL functions with
2308 arguments. It receives an array reference containing the function name
2309 as the 0th argument and the other arguments being its parameters. For example:
2312 -func => ['substr', 'Hello', 50, 5],
2317 $stmt = "WHERE (substr(?,?,?))";
2318 @bind = ("Hello", 50, 5);
2320 =head2 Unary operators: bool
2322 If you wish to test against boolean columns or functions within your
2323 database you can use the C<-bool> and C<-not_bool> operators. For
2324 example to test the column C<is_user> being true and the column
2325 C<is_enabled> being false you would use:-
2329 -not_bool => 'is_enabled',
2334 WHERE is_user AND NOT is_enabled
2336 If a more complex combination is required, testing more conditions,
2337 then you should use the and/or operators:-
2344 -not_bool => 'four',
2350 WHERE one AND two AND three AND NOT four
2353 =head2 Nested conditions, -and/-or prefixes
2355 So far, we've seen how multiple conditions are joined with a top-level
2356 C<AND>. We can change this by putting the different conditions we want in
2357 hashes and then putting those hashes in an array. For example:
2362 status => { -like => ['pending%', 'dispatched'] },
2366 status => 'unassigned',
2370 This data structure would create the following:
2372 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2373 OR ( user = ? AND status = ? ) )";
2374 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2377 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2378 to change the logic inside :
2384 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2385 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2392 WHERE ( user = ? AND (
2393 ( workhrs > ? AND geo = ? )
2394 OR ( workhrs < ? OR geo = ? )
2397 =head2 Algebraic inconsistency, for historical reasons
2399 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2400 operator goes C<outside> of the nested structure; whereas when connecting
2401 several constraints on one column, the C<-and> operator goes
2402 C<inside> the arrayref. Here is an example combining both features :
2405 -and => [a => 1, b => 2],
2406 -or => [c => 3, d => 4],
2407 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2412 WHERE ( ( ( a = ? AND b = ? )
2413 OR ( c = ? OR d = ? )
2414 OR ( e LIKE ? AND e LIKE ? ) ) )
2416 This difference in syntax is unfortunate but must be preserved for
2417 historical reasons. So be careful : the two examples below would
2418 seem algebraically equivalent, but they are not
2420 {col => [-and => {-like => 'foo%'}, {-like => '%bar'}]}
2421 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2423 [-and => {col => {-like => 'foo%'}, {col => {-like => '%bar'}}]]
2424 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2429 Finally, sometimes only literal SQL will do. If you want to include
2430 literal SQL verbatim, you can specify it as a scalar reference, namely:
2432 my $inn = 'is Not Null';
2434 priority => { '<', 2 },
2440 $stmt = "WHERE priority < ? AND requestor is Not Null";
2443 Note that in this example, you only get one bind parameter back, since
2444 the verbatim SQL is passed as part of the statement.
2446 Of course, just to prove a point, the above can also be accomplished
2450 priority => { '<', 2 },
2451 requestor => { '!=', undef },
2457 Conditions on boolean columns can be expressed in the same way, passing
2458 a reference to an empty string, however using liternal SQL in this way
2459 is deprecated - the preferred method is to use the boolean operators -
2460 see L</"Unary operators: bool"> :
2463 priority => { '<', 2 },
2469 $stmt = "WHERE priority < ? AND is_ready";
2472 Literal SQL is also the only way to compare 2 columns to one another:
2475 priority => { '<', 2 },
2476 requestor => \'= submittor'
2481 $stmt = "WHERE priority < ? AND requestor = submitter";
2484 =head2 Literal SQL with placeholders and bind values (subqueries)
2486 If the literal SQL to be inserted has placeholders and bind values,
2487 use a reference to an arrayref (yes this is a double reference --
2488 not so common, but perfectly legal Perl). For example, to find a date
2489 in Postgres you can use something like this:
2492 date_column => \[q/= date '2008-09-30' - ?::integer/, 10/]
2497 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2500 Note that you must pass the bind values in the same format as they are returned
2501 by L</where>. That means that if you set L</bindtype> to C<columns>, you must
2502 provide the bind values in the C<< [ column_meta => value ] >> format, where
2503 C<column_meta> is an opaque scalar value; most commonly the column name, but
2504 you can use any scalar value (including references and blessed references),
2505 L<SQL::Abstract> will simply pass it through intact. So if C<bindtype> is set
2506 to C<columns> the above example will look like:
2509 date_column => \[q/= date '2008-09-30' - ?::integer/, [ dummy => 10 ]/]
2512 Literal SQL is especially useful for nesting parenthesized clauses in the
2513 main SQL query. Here is a first example :
2515 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2519 bar => \["IN ($sub_stmt)" => @sub_bind],
2524 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2525 WHERE c2 < ? AND c3 LIKE ?))";
2526 @bind = (1234, 100, "foo%");
2528 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2529 are expressed in the same way. Of course the C<$sub_stmt> and
2530 its associated bind values can be generated through a former call
2533 my ($sub_stmt, @sub_bind)
2534 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2535 c3 => {-like => "foo%"}});
2538 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2541 In the examples above, the subquery was used as an operator on a column;
2542 but the same principle also applies for a clause within the main C<%where>
2543 hash, like an EXISTS subquery :
2545 my ($sub_stmt, @sub_bind)
2546 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2547 my %where = ( -and => [
2549 \["EXISTS ($sub_stmt)" => @sub_bind],
2554 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2555 WHERE c1 = ? AND c2 > t0.c0))";
2559 Observe that the condition on C<c2> in the subquery refers to
2560 column C<t0.c0> of the main query : this is I<not> a bind
2561 value, so we have to express it through a scalar ref.
2562 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2563 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2564 what we wanted here.
2566 Finally, here is an example where a subquery is used
2567 for expressing unary negation:
2569 my ($sub_stmt, @sub_bind)
2570 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2571 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2573 lname => {like => '%son%'},
2574 \["NOT ($sub_stmt)" => @sub_bind],
2579 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2580 @bind = ('%son%', 10, 20)
2586 These pages could go on for a while, since the nesting of the data
2587 structures this module can handle are pretty much unlimited (the
2588 module implements the C<WHERE> expansion as a recursive function
2589 internally). Your best bet is to "play around" with the module a
2590 little to see how the data structures behave, and choose the best
2591 format for your data based on that.
2593 And of course, all the values above will probably be replaced with
2594 variables gotten from forms or the command line. After all, if you
2595 knew everything ahead of time, you wouldn't have to worry about
2596 dynamically-generating SQL and could just hardwire it into your
2602 =head1 ORDER BY CLAUSES
2604 Some functions take an order by clause. This can either be a scalar (just a
2605 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2606 or an array of either of the two previous forms. Examples:
2608 Given | Will Generate
2609 ----------------------------------------------------------
2611 \'colA DESC' | ORDER BY colA DESC
2613 'colA' | ORDER BY colA
2615 [qw/colA colB/] | ORDER BY colA, colB
2617 {-asc => 'colA'} | ORDER BY colA ASC
2619 {-desc => 'colB'} | ORDER BY colB DESC
2621 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2623 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2626 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2627 { -desc => [qw/colB/], | colC ASC, colD ASC
2628 { -asc => [qw/colC colD/],|
2630 ===========================================================
2634 =head1 SPECIAL OPERATORS
2636 my $sqlmaker = SQL::Abstract->new(special_ops => [
2640 my ($self, $field, $op, $arg) = @_;
2646 handler => 'method_name',
2650 A "special operator" is a SQL syntactic clause that can be
2651 applied to a field, instead of a usual binary operator.
2654 WHERE field IN (?, ?, ?)
2655 WHERE field BETWEEN ? AND ?
2656 WHERE MATCH(field) AGAINST (?, ?)
2658 Special operators IN and BETWEEN are fairly standard and therefore
2659 are builtin within C<SQL::Abstract> (as the overridable methods
2660 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2661 like the MATCH .. AGAINST example above which is specific to MySQL,
2662 you can write your own operator handlers - supply a C<special_ops>
2663 argument to the C<new> method. That argument takes an arrayref of
2664 operator definitions; each operator definition is a hashref with two
2671 the regular expression to match the operator
2675 Either a coderef or a plain scalar method name. In both cases
2676 the expected return is C<< ($sql, @bind) >>.
2678 When supplied with a method name, it is simply called on the
2679 L<SQL::Abstract/> object as:
2681 $self->$method_name ($field, $op, $arg)
2685 $op is the part that matched the handler regex
2686 $field is the LHS of the operator
2689 When supplied with a coderef, it is called as:
2691 $coderef->($self, $field, $op, $arg)
2696 For example, here is an implementation
2697 of the MATCH .. AGAINST syntax for MySQL
2699 my $sqlmaker = SQL::Abstract->new(special_ops => [
2701 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2702 {regex => qr/^match$/i,
2704 my ($self, $field, $op, $arg) = @_;
2705 $arg = [$arg] if not ref $arg;
2706 my $label = $self->_quote($field);
2707 my ($placeholder) = $self->_convert('?');
2708 my $placeholders = join ", ", (($placeholder) x @$arg);
2709 my $sql = $self->_sqlcase('match') . " ($label) "
2710 . $self->_sqlcase('against') . " ($placeholders) ";
2711 my @bind = $self->_bindtype($field, @$arg);
2712 return ($sql, @bind);
2719 =head1 UNARY OPERATORS
2721 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2725 my ($self, $op, $arg) = @_;
2731 handler => 'method_name',
2735 A "unary operator" is a SQL syntactic clause that can be
2736 applied to a field - the operator goes before the field
2738 You can write your own operator handlers - supply a C<unary_ops>
2739 argument to the C<new> method. That argument takes an arrayref of
2740 operator definitions; each operator definition is a hashref with two
2747 the regular expression to match the operator
2751 Either a coderef or a plain scalar method name. In both cases
2752 the expected return is C<< $sql >>.
2754 When supplied with a method name, it is simply called on the
2755 L<SQL::Abstract/> object as:
2757 $self->$method_name ($op, $arg)
2761 $op is the part that matched the handler regex
2762 $arg is the RHS or argument of the operator
2764 When supplied with a coderef, it is called as:
2766 $coderef->($self, $op, $arg)
2774 Thanks to some benchmarking by Mark Stosberg, it turns out that
2775 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
2776 I must admit this wasn't an intentional design issue, but it's a
2777 byproduct of the fact that you get to control your C<DBI> handles
2780 To maximize performance, use a code snippet like the following:
2782 # prepare a statement handle using the first row
2783 # and then reuse it for the rest of the rows
2785 for my $href (@array_of_hashrefs) {
2786 $stmt ||= $sql->insert('table', $href);
2787 $sth ||= $dbh->prepare($stmt);
2788 $sth->execute($sql->values($href));
2791 The reason this works is because the keys in your C<$href> are sorted
2792 internally by B<SQL::Abstract>. Thus, as long as your data retains
2793 the same structure, you only have to generate the SQL the first time
2794 around. On subsequent queries, simply use the C<values> function provided
2795 by this module to return your values in the correct order.
2797 However this depends on the values having the same type - if, for
2798 example, the values of a where clause may either have values
2799 (resulting in sql of the form C<column = ?> with a single bind
2800 value), or alternatively the values might be C<undef> (resulting in
2801 sql of the form C<column IS NULL> with no bind value) then the
2802 caching technique suggested will not work.
2806 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
2807 really like this part (I do, at least). Building up a complex query
2808 can be as simple as the following:
2812 use CGI::FormBuilder;
2815 my $form = CGI::FormBuilder->new(...);
2816 my $sql = SQL::Abstract->new;
2818 if ($form->submitted) {
2819 my $field = $form->field;
2820 my $id = delete $field->{id};
2821 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
2824 Of course, you would still have to connect using C<DBI> to run the
2825 query, but the point is that if you make your form look like your
2826 table, the actual query script can be extremely simplistic.
2828 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
2829 a fast interface to returning and formatting data. I frequently
2830 use these three modules together to write complex database query
2831 apps in under 50 lines.
2837 =item * gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/DBIx-Class.git>
2839 =item * git: L<git://git.shadowcat.co.uk/dbsrgits/DBIx-Class.git>
2845 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
2846 Great care has been taken to preserve the I<published> behavior
2847 documented in previous versions in the 1.* family; however,
2848 some features that were previously undocumented, or behaved
2849 differently from the documentation, had to be changed in order
2850 to clarify the semantics. Hence, client code that was relying
2851 on some dark areas of C<SQL::Abstract> v1.*
2852 B<might behave differently> in v1.50.
2854 The main changes are :
2860 support for literal SQL through the C<< \ [$sql, bind] >> syntax.
2864 support for the { operator => \"..." } construct (to embed literal SQL)
2868 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
2872 optional support for L<array datatypes|/"Inserting and Updating Arrays">
2876 defensive programming : check arguments
2880 fixed bug with global logic, which was previously implemented
2881 through global variables yielding side-effects. Prior versions would
2882 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
2883 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
2884 Now this is interpreted
2885 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
2890 fixed semantics of _bindtype on array args
2894 dropped the C<_anoncopy> of the %where tree. No longer necessary,
2895 we just avoid shifting arrays within that tree.
2899 dropped the C<_modlogic> function
2905 =head1 ACKNOWLEDGEMENTS
2907 There are a number of individuals that have really helped out with
2908 this module. Unfortunately, most of them submitted bugs via CPAN
2909 so I have no idea who they are! But the people I do know are:
2911 Ash Berlin (order_by hash term support)
2912 Matt Trout (DBIx::Class support)
2913 Mark Stosberg (benchmarking)
2914 Chas Owens (initial "IN" operator support)
2915 Philip Collins (per-field SQL functions)
2916 Eric Kolve (hashref "AND" support)
2917 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
2918 Dan Kubb (support for "quote_char" and "name_sep")
2919 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
2920 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
2921 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
2922 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
2923 Oliver Charles (support for "RETURNING" after "INSERT")
2929 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
2933 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
2935 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
2937 For support, your best bet is to try the C<DBIx::Class> users mailing list.
2938 While not an official support venue, C<DBIx::Class> makes heavy use of
2939 C<SQL::Abstract>, and as such list members there are very familiar with
2940 how to create queries.
2944 This module is free software; you may copy this under the same
2945 terms as perl itself (either the GNU General Public License or
2946 the Artistic License)