1 package SQL::Abstract; # see doc at end of file
10 our @EXPORT_OK = qw(is_plain_value is_literal_value);
20 *SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION = $ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}
26 #======================================================================
28 #======================================================================
30 our $VERSION = '1.79';
32 # This would confuse some packagers
33 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
37 # special operators (-in, -between). May be extended/overridden by user.
38 # See section WHERE: BUILTIN SPECIAL OPERATORS below for implementation
39 my @BUILTIN_SPECIAL_OPS = (
40 {regex => qr/^ (?: not \s )? between $/ix, handler => '_where_field_BETWEEN'},
41 {regex => qr/^ (?: not \s )? in $/ix, handler => '_where_field_IN'},
42 {regex => qr/^ ident $/ix, handler => '_where_op_IDENT'},
43 {regex => qr/^ value $/ix, handler => '_where_op_VALUE'},
44 {regex => qr/^ is (?: \s+ not )? $/ix, handler => '_where_field_IS'},
47 # unaryish operators - key maps to handler
48 my @BUILTIN_UNARY_OPS = (
49 # the digits are backcompat stuff
50 { regex => qr/^ and (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
51 { regex => qr/^ or (?: [_\s]? \d+ )? $/xi, handler => '_where_op_ANDOR' },
52 { regex => qr/^ nest (?: [_\s]? \d+ )? $/xi, handler => '_where_op_NEST' },
53 { regex => qr/^ (?: not \s )? bool $/xi, handler => '_where_op_BOOL' },
54 { regex => qr/^ ident $/xi, handler => '_where_op_IDENT' },
55 { regex => qr/^ value $/xi, handler => '_where_op_VALUE' },
58 #======================================================================
59 # DEBUGGING AND ERROR REPORTING
60 #======================================================================
63 return unless $_[0]->{debug}; shift; # a little faster
64 my $func = (caller(1))[3];
65 warn "[$func] ", @_, "\n";
69 my($func) = (caller(1))[3];
70 Carp::carp "[$func] Warning: ", @_;
74 my($func) = (caller(1))[3];
75 Carp::croak "[$func] Fatal: ", @_;
78 sub is_literal_value ($) {
79 ref $_[0] eq 'SCALAR' ? [ ${$_[0]} ]
80 : ( ref $_[0] eq 'REF' and ref ${$_[0]} eq 'ARRAY' ) ? [ @${ $_[0] } ]
84 # FIXME XSify - this can be done so much more efficiently
85 sub is_plain_value ($) {
87 ! length ref $_[0] ? \($_[0])
89 ref $_[0] eq 'HASH' and keys %{$_[0]} == 1
91 exists $_[0]->{-value}
92 ) ? \($_[0]->{-value})
94 # reuse @_ for even moar speedz
95 defined ( $_[1] = Scalar::Util::blessed $_[0] )
97 # deliberately not using Devel::OverloadInfo - the checks we are
98 # intersted in are much more limited than the fullblown thing, and
99 # this is a very hot piece of code
101 # simply using ->can('(""') can leave behind stub methods that
102 # break actually using the overload later (see L<perldiag/Stub
103 # found while resolving method "%s" overloading "%s" in package
104 # "%s"> and the source of overload::mycan())
106 # either has stringification which DBI SHOULD prefer out of the box
107 grep { *{ (qq[${_}::(""]) }{CODE} } @{ $_[2] = mro::get_linear_isa( $_[1] ) }
109 # has nummification or boolification, AND fallback is *not* disabled
111 SQL::Abstract::_ENV_::DETECT_AUTOGENERATED_STRINGIFICATION
114 grep { *{"${_}::(0+"}{CODE} } @{$_[2]}
116 grep { *{"${_}::(bool"}{CODE} } @{$_[2]}
120 # no fallback specified at all
121 ! ( ($_[3]) = grep { *{"${_}::()"}{CODE} } @{$_[2]} )
123 # fallback explicitly undef
124 ! defined ${"$_[3]::()"}
137 #======================================================================
139 #======================================================================
143 my $class = ref($self) || $self;
144 my %opt = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
146 # choose our case by keeping an option around
147 delete $opt{case} if $opt{case} && $opt{case} ne 'lower';
149 # default logic for interpreting arrayrefs
150 $opt{logic} = $opt{logic} ? uc $opt{logic} : 'OR';
152 # how to return bind vars
153 $opt{bindtype} ||= 'normal';
155 # default comparison is "=", but can be overridden
158 # try to recognize which are the 'equality' and 'inequality' ops
159 # (temporary quickfix (in 2007), should go through a more seasoned API)
160 $opt{equality_op} = qr/^( \Q$opt{cmp}\E | \= )$/ix;
161 $opt{inequality_op} = qr/^( != | <> )$/ix;
163 $opt{like_op} = qr/^ (is\s+)? r?like $/xi;
164 $opt{not_like_op} = qr/^ (is\s+)? not \s+ r?like $/xi;
167 $opt{sqltrue} ||= '1=1';
168 $opt{sqlfalse} ||= '0=1';
171 $opt{special_ops} ||= [];
172 # regexes are applied in order, thus push after user-defines
173 push @{$opt{special_ops}}, @BUILTIN_SPECIAL_OPS;
176 $opt{unary_ops} ||= [];
177 push @{$opt{unary_ops}}, @BUILTIN_UNARY_OPS;
179 # rudimentary sanity-check for user supplied bits treated as functions/operators
180 # If a purported function matches this regular expression, an exception is thrown.
181 # Literal SQL is *NOT* subject to this check, only functions (and column names
182 # when quoting is not in effect)
185 # need to guard against ()'s in column names too, but this will break tons of
186 # hacks... ideas anyone?
187 $opt{injection_guard} ||= qr/
193 return bless \%opt, $class;
197 sub _assert_pass_injection_guard {
198 if ($_[1] =~ $_[0]->{injection_guard}) {
199 my $class = ref $_[0];
200 puke "Possible SQL injection attempt '$_[1]'. If this is indeed a part of the "
201 . "desired SQL use literal SQL ( \'...' or \[ '...' ] ) or supply your own "
202 . "{injection_guard} attribute to ${class}->new()"
207 #======================================================================
209 #======================================================================
213 my $table = $self->_table(shift);
214 my $data = shift || return;
217 my $method = $self->_METHOD_FOR_refkind("_insert", $data);
218 my ($sql, @bind) = $self->$method($data);
219 $sql = join " ", $self->_sqlcase('insert into'), $table, $sql;
221 if ($options->{returning}) {
222 my ($s, @b) = $self->_insert_returning ($options);
227 return wantarray ? ($sql, @bind) : $sql;
230 sub _insert_returning {
231 my ($self, $options) = @_;
233 my $f = $options->{returning};
235 my $fieldlist = $self->_SWITCH_refkind($f, {
236 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$f;},
237 SCALAR => sub {$self->_quote($f)},
238 SCALARREF => sub {$$f},
240 return $self->_sqlcase(' returning ') . $fieldlist;
243 sub _insert_HASHREF { # explicit list of fields and then values
244 my ($self, $data) = @_;
246 my @fields = sort keys %$data;
248 my ($sql, @bind) = $self->_insert_values($data);
251 $_ = $self->_quote($_) foreach @fields;
252 $sql = "( ".join(", ", @fields).") ".$sql;
254 return ($sql, @bind);
257 sub _insert_ARRAYREF { # just generate values(?,?) part (no list of fields)
258 my ($self, $data) = @_;
260 # no names (arrayref) so can't generate bindtype
261 $self->{bindtype} ne 'columns'
262 or belch "can't do 'columns' bindtype when called with arrayref";
264 # fold the list of values into a hash of column name - value pairs
265 # (where the column names are artificially generated, and their
266 # lexicographical ordering keep the ordering of the original list)
267 my $i = "a"; # incremented values will be in lexicographical order
268 my $data_in_hash = { map { ($i++ => $_) } @$data };
270 return $self->_insert_values($data_in_hash);
273 sub _insert_ARRAYREFREF { # literal SQL with bind
274 my ($self, $data) = @_;
276 my ($sql, @bind) = @${$data};
277 $self->_assert_bindval_matches_bindtype(@bind);
279 return ($sql, @bind);
283 sub _insert_SCALARREF { # literal SQL without bind
284 my ($self, $data) = @_;
290 my ($self, $data) = @_;
292 my (@values, @all_bind);
293 foreach my $column (sort keys %$data) {
294 my $v = $data->{$column};
296 $self->_SWITCH_refkind($v, {
299 if ($self->{array_datatypes}) { # if array datatype are activated
301 push @all_bind, $self->_bindtype($column, $v);
303 else { # else literal SQL with bind
304 my ($sql, @bind) = @$v;
305 $self->_assert_bindval_matches_bindtype(@bind);
307 push @all_bind, @bind;
311 ARRAYREFREF => sub { # literal SQL with bind
312 my ($sql, @bind) = @${$v};
313 $self->_assert_bindval_matches_bindtype(@bind);
315 push @all_bind, @bind;
318 # THINK : anything useful to do with a HASHREF ?
319 HASHREF => sub { # (nothing, but old SQLA passed it through)
320 #TODO in SQLA >= 2.0 it will die instead
321 belch "HASH ref as bind value in insert is not supported";
323 push @all_bind, $self->_bindtype($column, $v);
326 SCALARREF => sub { # literal SQL without bind
330 SCALAR_or_UNDEF => sub {
332 push @all_bind, $self->_bindtype($column, $v);
339 my $sql = $self->_sqlcase('values')." ( ".join(", ", @values)." )";
340 return ($sql, @all_bind);
345 #======================================================================
347 #======================================================================
352 my $table = $self->_table(shift);
353 my $data = shift || return;
356 # first build the 'SET' part of the sql statement
357 my (@set, @all_bind);
358 puke "Unsupported data type specified to \$sql->update"
359 unless ref $data eq 'HASH';
361 for my $k (sort keys %$data) {
364 my $label = $self->_quote($k);
366 $self->_SWITCH_refkind($v, {
368 if ($self->{array_datatypes}) { # array datatype
369 push @set, "$label = ?";
370 push @all_bind, $self->_bindtype($k, $v);
372 else { # literal SQL with bind
373 my ($sql, @bind) = @$v;
374 $self->_assert_bindval_matches_bindtype(@bind);
375 push @set, "$label = $sql";
376 push @all_bind, @bind;
379 ARRAYREFREF => sub { # literal SQL with bind
380 my ($sql, @bind) = @${$v};
381 $self->_assert_bindval_matches_bindtype(@bind);
382 push @set, "$label = $sql";
383 push @all_bind, @bind;
385 SCALARREF => sub { # literal SQL without bind
386 push @set, "$label = $$v";
389 my ($op, $arg, @rest) = %$v;
391 puke 'Operator calls in update must be in the form { -op => $arg }'
392 if (@rest or not $op =~ /^\-(.+)/);
394 local $self->{_nested_func_lhs} = $k;
395 my ($sql, @bind) = $self->_where_unary_op ($1, $arg);
397 push @set, "$label = $sql";
398 push @all_bind, @bind;
400 SCALAR_or_UNDEF => sub {
401 push @set, "$label = ?";
402 push @all_bind, $self->_bindtype($k, $v);
408 my $sql = $self->_sqlcase('update') . " $table " . $self->_sqlcase('set ')
412 my($where_sql, @where_bind) = $self->where($where);
414 push @all_bind, @where_bind;
417 return wantarray ? ($sql, @all_bind) : $sql;
423 #======================================================================
425 #======================================================================
430 my $table = $self->_table(shift);
431 my $fields = shift || '*';
435 my($where_sql, @bind) = $self->where($where, $order);
437 my $f = (ref $fields eq 'ARRAY') ? join ', ', map { $self->_quote($_) } @$fields
439 my $sql = join(' ', $self->_sqlcase('select'), $f,
440 $self->_sqlcase('from'), $table)
443 return wantarray ? ($sql, @bind) : $sql;
446 #======================================================================
448 #======================================================================
453 my $table = $self->_table(shift);
457 my($where_sql, @bind) = $self->where($where);
458 my $sql = $self->_sqlcase('delete from') . " $table" . $where_sql;
460 return wantarray ? ($sql, @bind) : $sql;
464 #======================================================================
466 #======================================================================
470 # Finally, a separate routine just to handle WHERE clauses
472 my ($self, $where, $order) = @_;
475 my ($sql, @bind) = $self->_recurse_where($where);
476 $sql = $sql ? $self->_sqlcase(' where ') . "( $sql )" : '';
480 $sql .= $self->_order_by($order);
483 return wantarray ? ($sql, @bind) : $sql;
488 my ($self, $where, $logic) = @_;
490 # dispatch on appropriate method according to refkind of $where
491 my $method = $self->_METHOD_FOR_refkind("_where", $where);
493 my ($sql, @bind) = $self->$method($where, $logic);
495 # DBIx::Class used to call _recurse_where in scalar context
496 # something else might too...
498 return ($sql, @bind);
501 belch "Calling _recurse_where in scalar context is deprecated and will go away before 2.0";
508 #======================================================================
509 # WHERE: top-level ARRAYREF
510 #======================================================================
513 sub _where_ARRAYREF {
514 my ($self, $where, $logic) = @_;
516 $logic = uc($logic || $self->{logic});
517 $logic eq 'AND' or $logic eq 'OR' or puke "unknown logic: $logic";
519 my @clauses = @$where;
521 my (@sql_clauses, @all_bind);
522 # need to use while() so can shift() for pairs
524 my $el = shift @clauses;
526 $el = undef if (defined $el and ! length $el);
528 # switch according to kind of $el and get corresponding ($sql, @bind)
529 my ($sql, @bind) = $self->_SWITCH_refkind($el, {
531 # skip empty elements, otherwise get invalid trailing AND stuff
532 ARRAYREF => sub {$self->_recurse_where($el) if @$el},
536 $self->_assert_bindval_matches_bindtype(@b);
540 HASHREF => sub {$self->_recurse_where($el, 'and') if %$el},
542 SCALARREF => sub { ($$el); },
545 # top-level arrayref with scalars, recurse in pairs
546 $self->_recurse_where({$el => shift(@clauses)})
549 UNDEF => sub {puke "Supplying an empty left hand side argument is not supported in array-pairs" },
553 push @sql_clauses, $sql;
554 push @all_bind, @bind;
558 return $self->_join_sql_clauses($logic, \@sql_clauses, \@all_bind);
561 #======================================================================
562 # WHERE: top-level ARRAYREFREF
563 #======================================================================
565 sub _where_ARRAYREFREF {
566 my ($self, $where) = @_;
567 my ($sql, @bind) = @$$where;
568 $self->_assert_bindval_matches_bindtype(@bind);
569 return ($sql, @bind);
572 #======================================================================
573 # WHERE: top-level HASHREF
574 #======================================================================
577 my ($self, $where) = @_;
578 my (@sql_clauses, @all_bind);
580 for my $k (sort keys %$where) {
581 my $v = $where->{$k};
583 # ($k => $v) is either a special unary op or a regular hashpair
584 my ($sql, @bind) = do {
586 # put the operator in canonical form
588 $op = substr $op, 1; # remove initial dash
589 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
590 $op =~ s/\s+/ /g; # compress whitespace
592 # so that -not_foo works correctly
593 $op =~ s/^not_/NOT /i;
595 $self->_debug("Unary OP(-$op) within hashref, recursing...");
596 my ($s, @b) = $self->_where_unary_op ($op, $v);
598 # top level vs nested
599 # we assume that handled unary ops will take care of their ()s
601 List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}
603 defined($self->{_nested_func_lhs}) && ($self->{_nested_func_lhs} eq $k)
609 if (is_literal_value ($v) ) {
610 belch 'Hash-pairs consisting of an empty string with a literal are deprecated, and will be removed in 2.0: use -and => [ $literal ] instead';
613 puke "Supplying an empty left hand side argument is not supported in hash-pairs";
617 my $method = $self->_METHOD_FOR_refkind("_where_hashpair", $v);
618 $self->$method($k, $v);
622 push @sql_clauses, $sql;
623 push @all_bind, @bind;
626 return $self->_join_sql_clauses('and', \@sql_clauses, \@all_bind);
629 sub _where_unary_op {
630 my ($self, $op, $rhs) = @_;
632 if (my $op_entry = List::Util::first {$op =~ $_->{regex}} @{$self->{unary_ops}}) {
633 my $handler = $op_entry->{handler};
635 if (not ref $handler) {
636 if ($op =~ s/ [_\s]? \d+ $//x ) {
637 belch 'Use of [and|or|nest]_N modifiers is deprecated and will be removed in SQLA v2.0. '
638 . "You probably wanted ...-and => [ -$op => COND1, -$op => COND2 ... ]";
640 return $self->$handler ($op, $rhs);
642 elsif (ref $handler eq 'CODE') {
643 return $handler->($self, $op, $rhs);
646 puke "Illegal handler for operator $op - expecting a method name or a coderef";
650 $self->_debug("Generic unary OP: $op - recursing as function");
652 $self->_assert_pass_injection_guard($op);
654 my ($sql, @bind) = $self->_SWITCH_refkind ($rhs, {
656 puke "Illegal use of top-level '$op'"
657 unless $self->{_nested_func_lhs};
660 $self->_convert('?'),
661 $self->_bindtype($self->{_nested_func_lhs}, $rhs)
665 $self->_recurse_where ($rhs)
669 $sql = sprintf ('%s %s',
670 $self->_sqlcase($op),
674 return ($sql, @bind);
677 sub _where_op_ANDOR {
678 my ($self, $op, $v) = @_;
680 $self->_SWITCH_refkind($v, {
682 return $self->_where_ARRAYREF($v, $op);
686 return ( $op =~ /^or/i )
687 ? $self->_where_ARRAYREF( [ map { $_ => $v->{$_} } ( sort keys %$v ) ], $op )
688 : $self->_where_HASHREF($v);
692 puke "-$op => \\\$scalar makes little sense, use " .
694 ? '[ \$scalar, \%rest_of_conditions ] instead'
695 : '-and => [ \$scalar, \%rest_of_conditions ] instead'
700 puke "-$op => \\[...] makes little sense, use " .
702 ? '[ \[...], \%rest_of_conditions ] instead'
703 : '-and => [ \[...], \%rest_of_conditions ] instead'
707 SCALAR => sub { # permissively interpreted as SQL
708 puke "-$op => \$value makes little sense, use -bool => \$value instead";
712 puke "-$op => undef not supported";
718 my ($self, $op, $v) = @_;
720 $self->_SWITCH_refkind($v, {
722 SCALAR => sub { # permissively interpreted as SQL
723 belch "literal SQL should be -nest => \\'scalar' "
724 . "instead of -nest => 'scalar' ";
729 puke "-$op => undef not supported";
733 $self->_recurse_where ($v);
741 my ($self, $op, $v) = @_;
743 my ($s, @b) = $self->_SWITCH_refkind($v, {
744 SCALAR => sub { # interpreted as SQL column
745 $self->_convert($self->_quote($v));
749 puke "-$op => undef not supported";
753 $self->_recurse_where ($v);
757 $s = "(NOT $s)" if $op =~ /^not/i;
762 sub _where_op_IDENT {
764 my ($op, $rhs) = splice @_, -2;
765 if (! defined $rhs or length ref $rhs) {
766 puke "-$op requires a single plain scalar argument (a quotable identifier)";
769 # in case we are called as a top level special op (no '=')
772 $_ = $self->_convert($self->_quote($_)) for ($lhs, $rhs);
780 sub _where_op_VALUE {
782 my ($op, $rhs) = splice @_, -2;
784 # in case we are called as a top level special op (no '=')
788 if (! defined $rhs) {
790 ? $self->_convert($self->_quote($lhs)) . ' IS NULL'
797 ($lhs || $self->{_nested_func_lhs}),
804 $self->_convert($self->_quote($lhs)) . ' = ' . $self->_convert('?'),
808 $self->_convert('?'),
814 sub _where_hashpair_ARRAYREF {
815 my ($self, $k, $v) = @_;
818 my @v = @$v; # need copy because of shift below
819 $self->_debug("ARRAY($k) means distribute over elements");
821 # put apart first element if it is an operator (-and, -or)
823 (defined $v[0] && $v[0] =~ /^ - (?: AND|OR ) $/ix)
827 my @distributed = map { {$k => $_} } @v;
830 $self->_debug("OP($op) reinjected into the distributed array");
831 unshift @distributed, $op;
834 my $logic = $op ? substr($op, 1) : '';
836 return $self->_recurse_where(\@distributed, $logic);
839 $self->_debug("empty ARRAY($k) means 0=1");
840 return ($self->{sqlfalse});
844 sub _where_hashpair_HASHREF {
845 my ($self, $k, $v, $logic) = @_;
848 local $self->{_nested_func_lhs} = $self->{_nested_func_lhs};
850 my ($all_sql, @all_bind);
852 for my $orig_op (sort keys %$v) {
853 my $val = $v->{$orig_op};
855 # put the operator in canonical form
858 # FIXME - we need to phase out dash-less ops
859 $op =~ s/^-//; # remove possible initial dash
860 $op =~ s/^\s+|\s+$//g;# remove leading/trailing space
861 $op =~ s/\s+/ /g; # compress whitespace
863 $self->_assert_pass_injection_guard($op);
866 $op =~ s/^is_not/IS NOT/i;
868 # so that -not_foo works correctly
869 $op =~ s/^not_/NOT /i;
871 # another retarded special case: foo => { $op => { -value => undef } }
872 if (ref $val eq 'HASH' and keys %$val == 1 and exists $val->{-value} and ! defined $val->{-value} ) {
878 # CASE: col-value logic modifiers
879 if ( $orig_op =~ /^ \- (and|or) $/xi ) {
880 ($sql, @bind) = $self->_where_hashpair_HASHREF($k, $val, $1);
882 # CASE: special operators like -in or -between
883 elsif ( my $special_op = List::Util::first {$op =~ $_->{regex}} @{$self->{special_ops}} ) {
884 my $handler = $special_op->{handler};
886 puke "No handler supplied for special operator $orig_op";
888 elsif (not ref $handler) {
889 ($sql, @bind) = $self->$handler ($k, $op, $val);
891 elsif (ref $handler eq 'CODE') {
892 ($sql, @bind) = $handler->($self, $k, $op, $val);
895 puke "Illegal handler for special operator $orig_op - expecting a method name or a coderef";
899 $self->_SWITCH_refkind($val, {
901 ARRAYREF => sub { # CASE: col => {op => \@vals}
902 ($sql, @bind) = $self->_where_field_op_ARRAYREF($k, $op, $val);
905 ARRAYREFREF => sub { # CASE: col => {op => \[$sql, @bind]} (literal SQL with bind)
906 my ($sub_sql, @sub_bind) = @$$val;
907 $self->_assert_bindval_matches_bindtype(@sub_bind);
908 $sql = join ' ', $self->_convert($self->_quote($k)),
909 $self->_sqlcase($op),
914 UNDEF => sub { # CASE: col => {op => undef} : sql "IS (NOT)? NULL"
916 $op =~ /^not$/i ? 'is not' # legacy
917 : $op =~ $self->{equality_op} ? 'is'
918 : $op =~ $self->{like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is'
919 : $op =~ $self->{inequality_op} ? 'is not'
920 : $op =~ $self->{not_like_op} ? belch("Supplying an undefined argument to '@{[ uc $op]}' is deprecated") && 'is not'
921 : puke "unexpected operator '$orig_op' with undef operand";
923 $sql = $self->_quote($k) . $self->_sqlcase(" $is null");
926 FALLBACK => sub { # CASE: col => {op/func => $stuff}
928 # retain for proper column type bind
929 $self->{_nested_func_lhs} ||= $k;
931 ($sql, @bind) = $self->_where_unary_op ($op, $val);
934 $self->_convert($self->_quote($k)),
935 $self->{_nested_func_lhs} eq $k ? $sql : "($sql)", # top level vs nested
941 ($all_sql) = (defined $all_sql and $all_sql) ? $self->_join_sql_clauses($logic, [$all_sql, $sql], []) : $sql;
942 push @all_bind, @bind;
944 return ($all_sql, @all_bind);
947 sub _where_field_IS {
948 my ($self, $k, $op, $v) = @_;
950 my ($s) = $self->_SWITCH_refkind($v, {
953 $self->_convert($self->_quote($k)),
954 map { $self->_sqlcase($_)} ($op, 'null')
957 puke "$op can only take undef as argument";
964 sub _where_field_op_ARRAYREF {
965 my ($self, $k, $op, $vals) = @_;
967 my @vals = @$vals; #always work on a copy
970 $self->_debug(sprintf '%s means multiple elements: [ %s ]',
972 join (', ', map { defined $_ ? "'$_'" : 'NULL' } @vals ),
975 # see if the first element is an -and/-or op
977 if (defined $vals[0] && $vals[0] =~ /^ - ( AND|OR ) $/ix) {
982 # a long standing API wart - an attempt to change this behavior during
983 # the 1.50 series failed *spectacularly*. Warn instead and leave the
988 (!$logic or $logic eq 'OR')
990 ( $op =~ $self->{inequality_op} or $op =~ $self->{not_like_op} )
993 belch "A multi-element arrayref as an argument to the inequality op '$o' "
994 . 'is technically equivalent to an always-true 1=1 (you probably wanted '
995 . "to say ...{ \$inequality_op => [ -and => \@values ] }... instead)"
999 # distribute $op over each remaining member of @vals, append logic if exists
1000 return $self->_recurse_where([map { {$k => {$op, $_}} } @vals], $logic);
1004 # try to DWIM on equality operators
1006 $op =~ $self->{equality_op} ? $self->{sqlfalse}
1007 : $op =~ $self->{like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqlfalse}
1008 : $op =~ $self->{inequality_op} ? $self->{sqltrue}
1009 : $op =~ $self->{not_like_op} ? belch("Supplying an empty arrayref to '@{[ uc $op]}' is deprecated") && $self->{sqltrue}
1010 : puke "operator '$op' applied on an empty array (field '$k')";
1015 sub _where_hashpair_SCALARREF {
1016 my ($self, $k, $v) = @_;
1017 $self->_debug("SCALAR($k) means literal SQL: $$v");
1018 my $sql = $self->_quote($k) . " " . $$v;
1022 # literal SQL with bind
1023 sub _where_hashpair_ARRAYREFREF {
1024 my ($self, $k, $v) = @_;
1025 $self->_debug("REF($k) means literal SQL: @${$v}");
1026 my ($sql, @bind) = @$$v;
1027 $self->_assert_bindval_matches_bindtype(@bind);
1028 $sql = $self->_quote($k) . " " . $sql;
1029 return ($sql, @bind );
1032 # literal SQL without bind
1033 sub _where_hashpair_SCALAR {
1034 my ($self, $k, $v) = @_;
1035 $self->_debug("NOREF($k) means simple key=val: $k $self->{cmp} $v");
1036 my $sql = join ' ', $self->_convert($self->_quote($k)),
1037 $self->_sqlcase($self->{cmp}),
1038 $self->_convert('?');
1039 my @bind = $self->_bindtype($k, $v);
1040 return ( $sql, @bind);
1044 sub _where_hashpair_UNDEF {
1045 my ($self, $k, $v) = @_;
1046 $self->_debug("UNDEF($k) means IS NULL");
1047 my $sql = $self->_quote($k) . $self->_sqlcase(' is null');
1051 #======================================================================
1052 # WHERE: TOP-LEVEL OTHERS (SCALARREF, SCALAR, UNDEF)
1053 #======================================================================
1056 sub _where_SCALARREF {
1057 my ($self, $where) = @_;
1060 $self->_debug("SCALAR(*top) means literal SQL: $$where");
1066 my ($self, $where) = @_;
1069 $self->_debug("NOREF(*top) means literal SQL: $where");
1080 #======================================================================
1081 # WHERE: BUILTIN SPECIAL OPERATORS (-in, -between)
1082 #======================================================================
1085 sub _where_field_BETWEEN {
1086 my ($self, $k, $op, $vals) = @_;
1088 my ($label, $and, $placeholder);
1089 $label = $self->_convert($self->_quote($k));
1090 $and = ' ' . $self->_sqlcase('and') . ' ';
1091 $placeholder = $self->_convert('?');
1092 $op = $self->_sqlcase($op);
1094 my $invalid_args = "Operator '$op' requires either an arrayref with two defined values or expressions, or a single literal scalarref/arrayref-ref";
1096 my ($clause, @bind) = $self->_SWITCH_refkind($vals, {
1097 ARRAYREFREF => sub {
1098 my ($s, @b) = @$$vals;
1099 $self->_assert_bindval_matches_bindtype(@b);
1106 puke $invalid_args if @$vals != 2;
1108 my (@all_sql, @all_bind);
1109 foreach my $val (@$vals) {
1110 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1112 return ($placeholder, $self->_bindtype($k, $val) );
1117 ARRAYREFREF => sub {
1118 my ($sql, @bind) = @$$val;
1119 $self->_assert_bindval_matches_bindtype(@bind);
1120 return ($sql, @bind);
1123 my ($func, $arg, @rest) = %$val;
1124 puke ("Only simple { -func => arg } functions accepted as sub-arguments to BETWEEN")
1125 if (@rest or $func !~ /^ \- (.+)/x);
1126 local $self->{_nested_func_lhs} = $k;
1127 $self->_where_unary_op ($1 => $arg);
1133 push @all_sql, $sql;
1134 push @all_bind, @bind;
1138 (join $and, @all_sql),
1147 my $sql = "( $label $op $clause )";
1148 return ($sql, @bind)
1152 sub _where_field_IN {
1153 my ($self, $k, $op, $vals) = @_;
1155 # backwards compatibility : if scalar, force into an arrayref
1156 $vals = [$vals] if defined $vals && ! ref $vals;
1158 my ($label) = $self->_convert($self->_quote($k));
1159 my ($placeholder) = $self->_convert('?');
1160 $op = $self->_sqlcase($op);
1162 my ($sql, @bind) = $self->_SWITCH_refkind($vals, {
1163 ARRAYREF => sub { # list of choices
1164 if (@$vals) { # nonempty list
1165 my (@all_sql, @all_bind);
1167 for my $val (@$vals) {
1168 my ($sql, @bind) = $self->_SWITCH_refkind($val, {
1170 return ($placeholder, $val);
1175 ARRAYREFREF => sub {
1176 my ($sql, @bind) = @$$val;
1177 $self->_assert_bindval_matches_bindtype(@bind);
1178 return ($sql, @bind);
1181 my ($func, $arg, @rest) = %$val;
1182 puke ("Only simple { -func => arg } functions accepted as sub-arguments to IN")
1183 if (@rest or $func !~ /^ \- (.+)/x);
1184 local $self->{_nested_func_lhs} = $k;
1185 $self->_where_unary_op ($1 => $arg);
1189 'SQL::Abstract before v1.75 used to generate incorrect SQL when the '
1190 . "-$op operator was given an undef-containing list: !!!AUDIT YOUR CODE "
1191 . 'AND DATA!!! (the upcoming Data::Query-based version of SQL::Abstract '
1192 . 'will emit the logically correct SQL instead of raising this exception)'
1196 push @all_sql, $sql;
1197 push @all_bind, @bind;
1201 sprintf ('%s %s ( %s )',
1204 join (', ', @all_sql)
1206 $self->_bindtype($k, @all_bind),
1209 else { # empty list : some databases won't understand "IN ()", so DWIM
1210 my $sql = ($op =~ /\bnot\b/i) ? $self->{sqltrue} : $self->{sqlfalse};
1215 SCALARREF => sub { # literal SQL
1216 my $sql = $self->_open_outer_paren ($$vals);
1217 return ("$label $op ( $sql )");
1219 ARRAYREFREF => sub { # literal SQL with bind
1220 my ($sql, @bind) = @$$vals;
1221 $self->_assert_bindval_matches_bindtype(@bind);
1222 $sql = $self->_open_outer_paren ($sql);
1223 return ("$label $op ( $sql )", @bind);
1227 puke "Argument passed to the '$op' operator can not be undefined";
1231 puke "special op $op requires an arrayref (or scalarref/arrayref-ref)";
1235 return ($sql, @bind);
1238 # Some databases (SQLite) treat col IN (1, 2) different from
1239 # col IN ( (1, 2) ). Use this to strip all outer parens while
1240 # adding them back in the corresponding method
1241 sub _open_outer_paren {
1242 my ($self, $sql) = @_;
1243 $sql = $1 while $sql =~ /^ \s* \( (.*) \) \s* $/xs;
1248 #======================================================================
1250 #======================================================================
1253 my ($self, $arg) = @_;
1256 for my $c ($self->_order_by_chunks ($arg) ) {
1257 $self->_SWITCH_refkind ($c, {
1258 SCALAR => sub { push @sql, $c },
1259 ARRAYREF => sub { push @sql, shift @$c; push @bind, @$c },
1265 $self->_sqlcase(' order by'),
1271 return wantarray ? ($sql, @bind) : $sql;
1274 sub _order_by_chunks {
1275 my ($self, $arg) = @_;
1277 return $self->_SWITCH_refkind($arg, {
1280 map { $self->_order_by_chunks ($_ ) } @$arg;
1283 ARRAYREFREF => sub {
1284 my ($s, @b) = @$$arg;
1285 $self->_assert_bindval_matches_bindtype(@b);
1289 SCALAR => sub {$self->_quote($arg)},
1291 UNDEF => sub {return () },
1293 SCALARREF => sub {$$arg}, # literal SQL, no quoting
1296 # get first pair in hash
1297 my ($key, $val, @rest) = %$arg;
1299 return () unless $key;
1301 if ( @rest or not $key =~ /^-(desc|asc)/i ) {
1302 puke "hash passed to _order_by must have exactly one key (-desc or -asc)";
1308 for my $c ($self->_order_by_chunks ($val)) {
1311 $self->_SWITCH_refkind ($c, {
1316 ($sql, @bind) = @$c;
1320 $sql = $sql . ' ' . $self->_sqlcase($direction);
1322 push @ret, [ $sql, @bind];
1331 #======================================================================
1332 # DATASOURCE (FOR NOW, JUST PLAIN TABLE OR LIST OF TABLES)
1333 #======================================================================
1338 $self->_SWITCH_refkind($from, {
1339 ARRAYREF => sub {join ', ', map { $self->_quote($_) } @$from;},
1340 SCALAR => sub {$self->_quote($from)},
1341 SCALARREF => sub {$$from},
1346 #======================================================================
1348 #======================================================================
1350 # highly optimized, as it's called way too often
1352 # my ($self, $label) = @_;
1354 return '' unless defined $_[1];
1355 return ${$_[1]} if ref($_[1]) eq 'SCALAR';
1357 unless ($_[0]->{quote_char}) {
1358 $_[0]->_assert_pass_injection_guard($_[1]);
1362 my $qref = ref $_[0]->{quote_char};
1365 ($l, $r) = ( $_[0]->{quote_char}, $_[0]->{quote_char} );
1367 elsif ($qref eq 'ARRAY') {
1368 ($l, $r) = @{$_[0]->{quote_char}};
1371 puke "Unsupported quote_char format: $_[0]->{quote_char}";
1373 my $esc = $_[0]->{escape_char} || $r;
1375 # parts containing * are naturally unquoted
1376 return join( $_[0]->{name_sep}||'', map
1377 { $_ eq '*' ? $_ : do { (my $n = $_) =~ s/(\Q$esc\E|\Q$r\E)/$esc$1/g; $l . $n . $r } }
1378 ( $_[0]->{name_sep} ? split (/\Q$_[0]->{name_sep}\E/, $_[1] ) : $_[1] )
1383 # Conversion, if applicable
1385 #my ($self, $arg) = @_;
1386 if ($_[0]->{convert}) {
1387 return $_[0]->_sqlcase($_[0]->{convert}) .'(' . $_[1] . ')';
1394 #my ($self, $col, @vals) = @_;
1395 # called often - tighten code
1396 return $_[0]->{bindtype} eq 'columns'
1397 ? map {[$_[1], $_]} @_[2 .. $#_]
1402 # Dies if any element of @bind is not in [colname => value] format
1403 # if bindtype is 'columns'.
1404 sub _assert_bindval_matches_bindtype {
1405 # my ($self, @bind) = @_;
1407 if ($self->{bindtype} eq 'columns') {
1409 if (!defined $_ || ref($_) ne 'ARRAY' || @$_ != 2) {
1410 puke "bindtype 'columns' selected, you need to pass: [column_name => bind_value]"
1416 sub _join_sql_clauses {
1417 my ($self, $logic, $clauses_aref, $bind_aref) = @_;
1419 if (@$clauses_aref > 1) {
1420 my $join = " " . $self->_sqlcase($logic) . " ";
1421 my $sql = '( ' . join($join, @$clauses_aref) . ' )';
1422 return ($sql, @$bind_aref);
1424 elsif (@$clauses_aref) {
1425 return ($clauses_aref->[0], @$bind_aref); # no parentheses
1428 return (); # if no SQL, ignore @$bind_aref
1433 # Fix SQL case, if so requested
1435 # LDNOTE: if $self->{case} is true, then it contains 'lower', so we
1436 # don't touch the argument ... crooked logic, but let's not change it!
1437 return $_[0]->{case} ? $_[1] : uc($_[1]);
1441 #======================================================================
1442 # DISPATCHING FROM REFKIND
1443 #======================================================================
1446 my ($self, $data) = @_;
1448 return 'UNDEF' unless defined $data;
1450 # blessed objects are treated like scalars
1451 my $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1453 return 'SCALAR' unless $ref;
1456 while ($ref eq 'REF') {
1458 $ref = (Scalar::Util::blessed $data) ? '' : ref $data;
1462 return ($ref||'SCALAR') . ('REF' x $n_steps);
1466 my ($self, $data) = @_;
1467 my @try = ($self->_refkind($data));
1468 push @try, 'SCALAR_or_UNDEF' if $try[0] eq 'SCALAR' || $try[0] eq 'UNDEF';
1469 push @try, 'FALLBACK';
1473 sub _METHOD_FOR_refkind {
1474 my ($self, $meth_prefix, $data) = @_;
1477 for (@{$self->_try_refkind($data)}) {
1478 $method = $self->can($meth_prefix."_".$_)
1482 return $method || puke "cannot dispatch on '$meth_prefix' for ".$self->_refkind($data);
1486 sub _SWITCH_refkind {
1487 my ($self, $data, $dispatch_table) = @_;
1490 for (@{$self->_try_refkind($data)}) {
1491 $coderef = $dispatch_table->{$_}
1495 puke "no dispatch entry for ".$self->_refkind($data)
1504 #======================================================================
1505 # VALUES, GENERATE, AUTOLOAD
1506 #======================================================================
1508 # LDNOTE: original code from nwiger, didn't touch code in that section
1509 # I feel the AUTOLOAD stuff should not be the default, it should
1510 # only be activated on explicit demand by user.
1514 my $data = shift || return;
1515 puke "Argument to ", __PACKAGE__, "->values must be a \\%hash"
1516 unless ref $data eq 'HASH';
1519 foreach my $k ( sort keys %$data ) {
1520 my $v = $data->{$k};
1521 $self->_SWITCH_refkind($v, {
1523 if ($self->{array_datatypes}) { # array datatype
1524 push @all_bind, $self->_bindtype($k, $v);
1526 else { # literal SQL with bind
1527 my ($sql, @bind) = @$v;
1528 $self->_assert_bindval_matches_bindtype(@bind);
1529 push @all_bind, @bind;
1532 ARRAYREFREF => sub { # literal SQL with bind
1533 my ($sql, @bind) = @${$v};
1534 $self->_assert_bindval_matches_bindtype(@bind);
1535 push @all_bind, @bind;
1537 SCALARREF => sub { # literal SQL without bind
1539 SCALAR_or_UNDEF => sub {
1540 push @all_bind, $self->_bindtype($k, $v);
1551 my(@sql, @sqlq, @sqlv);
1555 if ($ref eq 'HASH') {
1556 for my $k (sort keys %$_) {
1559 my $label = $self->_quote($k);
1560 if ($r eq 'ARRAY') {
1561 # literal SQL with bind
1562 my ($sql, @bind) = @$v;
1563 $self->_assert_bindval_matches_bindtype(@bind);
1564 push @sqlq, "$label = $sql";
1566 } elsif ($r eq 'SCALAR') {
1567 # literal SQL without bind
1568 push @sqlq, "$label = $$v";
1570 push @sqlq, "$label = ?";
1571 push @sqlv, $self->_bindtype($k, $v);
1574 push @sql, $self->_sqlcase('set'), join ', ', @sqlq;
1575 } elsif ($ref eq 'ARRAY') {
1576 # unlike insert(), assume these are ONLY the column names, i.e. for SQL
1579 if ($r eq 'ARRAY') { # literal SQL with bind
1580 my ($sql, @bind) = @$v;
1581 $self->_assert_bindval_matches_bindtype(@bind);
1584 } elsif ($r eq 'SCALAR') { # literal SQL without bind
1585 # embedded literal SQL
1592 push @sql, '(' . join(', ', @sqlq) . ')';
1593 } elsif ($ref eq 'SCALAR') {
1597 # strings get case twiddled
1598 push @sql, $self->_sqlcase($_);
1602 my $sql = join ' ', @sql;
1604 # this is pretty tricky
1605 # if ask for an array, return ($stmt, @bind)
1606 # otherwise, s/?/shift @sqlv/ to put it inline
1608 return ($sql, @sqlv);
1610 1 while $sql =~ s/\?/my $d = shift(@sqlv);
1611 ref $d ? $d->[1] : $d/e;
1620 # This allows us to check for a local, then _form, attr
1622 my($name) = $AUTOLOAD =~ /.*::(.+)/;
1623 return $self->generate($name, @_);
1634 SQL::Abstract - Generate SQL from Perl data structures
1640 my $sql = SQL::Abstract->new;
1642 my($stmt, @bind) = $sql->select($source, \@fields, \%where, \@order);
1644 my($stmt, @bind) = $sql->insert($table, \%fieldvals || \@values);
1646 my($stmt, @bind) = $sql->update($table, \%fieldvals, \%where);
1648 my($stmt, @bind) = $sql->delete($table, \%where);
1650 # Then, use these in your DBI statements
1651 my $sth = $dbh->prepare($stmt);
1652 $sth->execute(@bind);
1654 # Just generate the WHERE clause
1655 my($stmt, @bind) = $sql->where(\%where, \@order);
1657 # Return values in the same order, for hashed queries
1658 # See PERFORMANCE section for more details
1659 my @bind = $sql->values(\%fieldvals);
1663 This module was inspired by the excellent L<DBIx::Abstract>.
1664 However, in using that module I found that what I really wanted
1665 to do was generate SQL, but still retain complete control over my
1666 statement handles and use the DBI interface. So, I set out to
1667 create an abstract SQL generation module.
1669 While based on the concepts used by L<DBIx::Abstract>, there are
1670 several important differences, especially when it comes to WHERE
1671 clauses. I have modified the concepts used to make the SQL easier
1672 to generate from Perl data structures and, IMO, more intuitive.
1673 The underlying idea is for this module to do what you mean, based
1674 on the data structures you provide it. The big advantage is that
1675 you don't have to modify your code every time your data changes,
1676 as this module figures it out.
1678 To begin with, an SQL INSERT is as easy as just specifying a hash
1679 of C<key=value> pairs:
1682 name => 'Jimbo Bobson',
1683 phone => '123-456-7890',
1684 address => '42 Sister Lane',
1685 city => 'St. Louis',
1686 state => 'Louisiana',
1689 The SQL can then be generated with this:
1691 my($stmt, @bind) = $sql->insert('people', \%data);
1693 Which would give you something like this:
1695 $stmt = "INSERT INTO people
1696 (address, city, name, phone, state)
1697 VALUES (?, ?, ?, ?, ?)";
1698 @bind = ('42 Sister Lane', 'St. Louis', 'Jimbo Bobson',
1699 '123-456-7890', 'Louisiana');
1701 These are then used directly in your DBI code:
1703 my $sth = $dbh->prepare($stmt);
1704 $sth->execute(@bind);
1706 =head2 Inserting and Updating Arrays
1708 If your database has array types (like for example Postgres),
1709 activate the special option C<< array_datatypes => 1 >>
1710 when creating the C<SQL::Abstract> object.
1711 Then you may use an arrayref to insert and update database array types:
1713 my $sql = SQL::Abstract->new(array_datatypes => 1);
1715 planets => [qw/Mercury Venus Earth Mars/]
1718 my($stmt, @bind) = $sql->insert('solar_system', \%data);
1722 $stmt = "INSERT INTO solar_system (planets) VALUES (?)"
1724 @bind = (['Mercury', 'Venus', 'Earth', 'Mars']);
1727 =head2 Inserting and Updating SQL
1729 In order to apply SQL functions to elements of your C<%data> you may
1730 specify a reference to an arrayref for the given hash value. For example,
1731 if you need to execute the Oracle C<to_date> function on a value, you can
1732 say something like this:
1736 date_entered => \[ "to_date(?,'MM/DD/YYYY')", "03/02/2003" ],
1739 The first value in the array is the actual SQL. Any other values are
1740 optional and would be included in the bind values array. This gives
1743 my($stmt, @bind) = $sql->insert('people', \%data);
1745 $stmt = "INSERT INTO people (name, date_entered)
1746 VALUES (?, to_date(?,'MM/DD/YYYY'))";
1747 @bind = ('Bill', '03/02/2003');
1749 An UPDATE is just as easy, all you change is the name of the function:
1751 my($stmt, @bind) = $sql->update('people', \%data);
1753 Notice that your C<%data> isn't touched; the module will generate
1754 the appropriately quirky SQL for you automatically. Usually you'll
1755 want to specify a WHERE clause for your UPDATE, though, which is
1756 where handling C<%where> hashes comes in handy...
1758 =head2 Complex where statements
1760 This module can generate pretty complicated WHERE statements
1761 easily. For example, simple C<key=value> pairs are taken to mean
1762 equality, and if you want to see if a field is within a set
1763 of values, you can use an arrayref. Let's say we wanted to
1764 SELECT some data based on this criteria:
1767 requestor => 'inna',
1768 worker => ['nwiger', 'rcwe', 'sfz'],
1769 status => { '!=', 'completed' }
1772 my($stmt, @bind) = $sql->select('tickets', '*', \%where);
1774 The above would give you something like this:
1776 $stmt = "SELECT * FROM tickets WHERE
1777 ( requestor = ? ) AND ( status != ? )
1778 AND ( worker = ? OR worker = ? OR worker = ? )";
1779 @bind = ('inna', 'completed', 'nwiger', 'rcwe', 'sfz');
1781 Which you could then use in DBI code like so:
1783 my $sth = $dbh->prepare($stmt);
1784 $sth->execute(@bind);
1790 The methods are simple. There's one for every major SQL operation,
1791 and a constructor you use first. The arguments are specified in a
1792 similar order for each method (table, then fields, then a where
1793 clause) to try and simplify things.
1795 =head2 new(option => 'value')
1797 The C<new()> function takes a list of options and values, and returns
1798 a new B<SQL::Abstract> object which can then be used to generate SQL
1799 through the methods below. The options accepted are:
1805 If set to 'lower', then SQL will be generated in all lowercase. By
1806 default SQL is generated in "textbook" case meaning something like:
1808 SELECT a_field FROM a_table WHERE some_field LIKE '%someval%'
1810 Any setting other than 'lower' is ignored.
1814 This determines what the default comparison operator is. By default
1815 it is C<=>, meaning that a hash like this:
1817 %where = (name => 'nwiger', email => 'nate@wiger.org');
1819 Will generate SQL like this:
1821 WHERE name = 'nwiger' AND email = 'nate@wiger.org'
1823 However, you may want loose comparisons by default, so if you set
1824 C<cmp> to C<like> you would get SQL such as:
1826 WHERE name like 'nwiger' AND email like 'nate@wiger.org'
1828 You can also override the comparison on an individual basis - see
1829 the huge section on L</"WHERE CLAUSES"> at the bottom.
1831 =item sqltrue, sqlfalse
1833 Expressions for inserting boolean values within SQL statements.
1834 By default these are C<1=1> and C<1=0>. They are used
1835 by the special operators C<-in> and C<-not_in> for generating
1836 correct SQL even when the argument is an empty array (see below).
1840 This determines the default logical operator for multiple WHERE
1841 statements in arrays or hashes. If absent, the default logic is "or"
1842 for arrays, and "and" for hashes. This means that a WHERE
1846 event_date => {'>=', '2/13/99'},
1847 event_date => {'<=', '4/24/03'},
1850 will generate SQL like this:
1852 WHERE event_date >= '2/13/99' OR event_date <= '4/24/03'
1854 This is probably not what you want given this query, though (look
1855 at the dates). To change the "OR" to an "AND", simply specify:
1857 my $sql = SQL::Abstract->new(logic => 'and');
1859 Which will change the above C<WHERE> to:
1861 WHERE event_date >= '2/13/99' AND event_date <= '4/24/03'
1863 The logic can also be changed locally by inserting
1864 a modifier in front of an arrayref :
1866 @where = (-and => [event_date => {'>=', '2/13/99'},
1867 event_date => {'<=', '4/24/03'} ]);
1869 See the L</"WHERE CLAUSES"> section for explanations.
1873 This will automatically convert comparisons using the specified SQL
1874 function for both column and value. This is mostly used with an argument
1875 of C<upper> or C<lower>, so that the SQL will have the effect of
1876 case-insensitive "searches". For example, this:
1878 $sql = SQL::Abstract->new(convert => 'upper');
1879 %where = (keywords => 'MaKe iT CAse inSeNSItive');
1881 Will turn out the following SQL:
1883 WHERE upper(keywords) like upper('MaKe iT CAse inSeNSItive')
1885 The conversion can be C<upper()>, C<lower()>, or any other SQL function
1886 that can be applied symmetrically to fields (actually B<SQL::Abstract> does
1887 not validate this option; it will just pass through what you specify verbatim).
1891 This is a kludge because many databases suck. For example, you can't
1892 just bind values using DBI's C<execute()> for Oracle C<CLOB> or C<BLOB> fields.
1893 Instead, you have to use C<bind_param()>:
1895 $sth->bind_param(1, 'reg data');
1896 $sth->bind_param(2, $lots, {ora_type => ORA_CLOB});
1898 The problem is, B<SQL::Abstract> will normally just return a C<@bind> array,
1899 which loses track of which field each slot refers to. Fear not.
1901 If you specify C<bindtype> in new, you can determine how C<@bind> is returned.
1902 Currently, you can specify either C<normal> (default) or C<columns>. If you
1903 specify C<columns>, you will get an array that looks like this:
1905 my $sql = SQL::Abstract->new(bindtype => 'columns');
1906 my($stmt, @bind) = $sql->insert(...);
1909 [ 'column1', 'value1' ],
1910 [ 'column2', 'value2' ],
1911 [ 'column3', 'value3' ],
1914 You can then iterate through this manually, using DBI's C<bind_param()>.
1916 $sth->prepare($stmt);
1919 my($col, $data) = @$_;
1920 if ($col eq 'details' || $col eq 'comments') {
1921 $sth->bind_param($i, $data, {ora_type => ORA_CLOB});
1922 } elsif ($col eq 'image') {
1923 $sth->bind_param($i, $data, {ora_type => ORA_BLOB});
1925 $sth->bind_param($i, $data);
1929 $sth->execute; # execute without @bind now
1931 Now, why would you still use B<SQL::Abstract> if you have to do this crap?
1932 Basically, the advantage is still that you don't have to care which fields
1933 are or are not included. You could wrap that above C<for> loop in a simple
1934 sub called C<bind_fields()> or something and reuse it repeatedly. You still
1935 get a layer of abstraction over manual SQL specification.
1937 Note that if you set L</bindtype> to C<columns>, the C<\[ $sql, @bind ]>
1938 construct (see L</Literal SQL with placeholders and bind values (subqueries)>)
1939 will expect the bind values in this format.
1943 This is the character that a table or column name will be quoted
1944 with. By default this is an empty string, but you could set it to
1945 the character C<`>, to generate SQL like this:
1947 SELECT `a_field` FROM `a_table` WHERE `some_field` LIKE '%someval%'
1949 Alternatively, you can supply an array ref of two items, the first being the left
1950 hand quote character, and the second the right hand quote character. For
1951 example, you could supply C<['[',']']> for SQL Server 2000 compliant quotes
1952 that generates SQL like this:
1954 SELECT [a_field] FROM [a_table] WHERE [some_field] LIKE '%someval%'
1956 Quoting is useful if you have tables or columns names that are reserved
1957 words in your database's SQL dialect.
1961 This is the character that will be used to escape L</quote_char>s appearing
1962 in an identifier before it has been quoted.
1964 The parameter default in case of a single L</quote_char> character is the quote
1967 When opening-closing-style quoting is used (L</quote_char> is an arrayref)
1968 this parameter defaults to the B<closing (right)> L</quote_char>. Occurences
1969 of the B<opening (left)> L</quote_char> within the identifier are currently left
1970 untouched. The default for opening-closing-style quotes may change in future
1971 versions, thus you are B<strongly encouraged> to specify the escape character
1976 This is the character that separates a table and column name. It is
1977 necessary to specify this when the C<quote_char> option is selected,
1978 so that tables and column names can be individually quoted like this:
1980 SELECT `table`.`one_field` FROM `table` WHERE `table`.`other_field` = 1
1982 =item injection_guard
1984 A regular expression C<qr/.../> that is applied to any C<-function> and unquoted
1985 column name specified in a query structure. This is a safety mechanism to avoid
1986 injection attacks when mishandling user input e.g.:
1988 my %condition_as_column_value_pairs = get_values_from_user();
1989 $sqla->select( ... , \%condition_as_column_value_pairs );
1991 If the expression matches an exception is thrown. Note that literal SQL
1992 supplied via C<\'...'> or C<\['...']> is B<not> checked in any way.
1994 Defaults to checking for C<;> and the C<GO> keyword (TransactSQL)
1996 =item array_datatypes
1998 When this option is true, arrayrefs in INSERT or UPDATE are
1999 interpreted as array datatypes and are passed directly
2001 When this option is false, arrayrefs are interpreted
2002 as literal SQL, just like refs to arrayrefs
2003 (but this behavior is for backwards compatibility; when writing
2004 new queries, use the "reference to arrayref" syntax
2010 Takes a reference to a list of "special operators"
2011 to extend the syntax understood by L<SQL::Abstract>.
2012 See section L</"SPECIAL OPERATORS"> for details.
2016 Takes a reference to a list of "unary operators"
2017 to extend the syntax understood by L<SQL::Abstract>.
2018 See section L</"UNARY OPERATORS"> for details.
2024 =head2 insert($table, \@values || \%fieldvals, \%options)
2026 This is the simplest function. You simply give it a table name
2027 and either an arrayref of values or hashref of field/value pairs.
2028 It returns an SQL INSERT statement and a list of bind values.
2029 See the sections on L</"Inserting and Updating Arrays"> and
2030 L</"Inserting and Updating SQL"> for information on how to insert
2031 with those data types.
2033 The optional C<\%options> hash reference may contain additional
2034 options to generate the insert SQL. Currently supported options
2041 Takes either a scalar of raw SQL fields, or an array reference of
2042 field names, and adds on an SQL C<RETURNING> statement at the end.
2043 This allows you to return data generated by the insert statement
2044 (such as row IDs) without performing another C<SELECT> statement.
2045 Note, however, this is not part of the SQL standard and may not
2046 be supported by all database engines.
2050 =head2 update($table, \%fieldvals, \%where)
2052 This takes a table, hashref of field/value pairs, and an optional
2053 hashref L<WHERE clause|/WHERE CLAUSES>. It returns an SQL UPDATE function and a list
2055 See the sections on L</"Inserting and Updating Arrays"> and
2056 L</"Inserting and Updating SQL"> for information on how to insert
2057 with those data types.
2059 =head2 select($source, $fields, $where, $order)
2061 This returns a SQL SELECT statement and associated list of bind values, as
2062 specified by the arguments :
2068 Specification of the 'FROM' part of the statement.
2069 The argument can be either a plain scalar (interpreted as a table
2070 name, will be quoted), or an arrayref (interpreted as a list
2071 of table names, joined by commas, quoted), or a scalarref
2072 (literal table name, not quoted), or a ref to an arrayref
2073 (list of literal table names, joined by commas, not quoted).
2077 Specification of the list of fields to retrieve from
2079 The argument can be either an arrayref (interpreted as a list
2080 of field names, will be joined by commas and quoted), or a
2081 plain scalar (literal SQL, not quoted).
2082 Please observe that this API is not as flexible as that of
2083 the first argument C<$source>, for backwards compatibility reasons.
2087 Optional argument to specify the WHERE part of the query.
2088 The argument is most often a hashref, but can also be
2089 an arrayref or plain scalar --
2090 see section L<WHERE clause|/"WHERE CLAUSES"> for details.
2094 Optional argument to specify the ORDER BY part of the query.
2095 The argument can be a scalar, a hashref or an arrayref
2096 -- see section L<ORDER BY clause|/"ORDER BY CLAUSES">
2102 =head2 delete($table, \%where)
2104 This takes a table name and optional hashref L<WHERE clause|/WHERE CLAUSES>.
2105 It returns an SQL DELETE statement and list of bind values.
2107 =head2 where(\%where, \@order)
2109 This is used to generate just the WHERE clause. For example,
2110 if you have an arbitrary data structure and know what the
2111 rest of your SQL is going to look like, but want an easy way
2112 to produce a WHERE clause, use this. It returns an SQL WHERE
2113 clause and list of bind values.
2116 =head2 values(\%data)
2118 This just returns the values from the hash C<%data>, in the same
2119 order that would be returned from any of the other above queries.
2120 Using this allows you to markedly speed up your queries if you
2121 are affecting lots of rows. See below under the L</"PERFORMANCE"> section.
2123 =head2 generate($any, 'number', $of, \@data, $struct, \%types)
2125 Warning: This is an experimental method and subject to change.
2127 This returns arbitrarily generated SQL. It's a really basic shortcut.
2128 It will return two different things, depending on return context:
2130 my($stmt, @bind) = $sql->generate('create table', \$table, \@fields);
2131 my $stmt_and_val = $sql->generate('create table', \$table, \@fields);
2133 These would return the following:
2135 # First calling form
2136 $stmt = "CREATE TABLE test (?, ?)";
2137 @bind = (field1, field2);
2139 # Second calling form
2140 $stmt_and_val = "CREATE TABLE test (field1, field2)";
2142 Depending on what you're trying to do, it's up to you to choose the correct
2143 format. In this example, the second form is what you would want.
2147 $sql->generate('alter session', { nls_date_format => 'MM/YY' });
2151 ALTER SESSION SET nls_date_format = 'MM/YY'
2153 You get the idea. Strings get their case twiddled, but everything
2154 else remains verbatim.
2156 =head1 EXPORTABLE FUNCTIONS
2158 =head2 is_plain_value
2160 Determines if the supplied argument is a plain value as understood by this
2165 =item * The value is C<undef>
2167 =item * The value is a non-reference
2169 =item * The value is an object with stringification overloading
2171 =item * The value is of the form C<< { -value => $anything } >>
2175 On failure returns C<undef>, on sucess returns a B<scalar> reference
2176 to the original supplied argument.
2182 The stringification overloading detection is rather advanced: it takes
2183 into consideration not only the presence of a C<""> overload, but if that
2184 fails also checks for enabled
2185 L<autogenerated versions of C<"">|overload/Magic Autogeneration>, based
2186 on either C<0+> or C<bool>.
2188 Unfortunately testing in the field indicates that this
2189 detection B<< may tickle a latent bug in perl versions before 5.018 >>,
2190 but only when very large numbers of stringifying objects are involved.
2191 At the time of writing ( Sep 2014 ) there is no clear explanation of
2192 the direct cause, nor is there a manageably small test case that reliably
2193 reproduces the problem.
2195 If you encounter any of the following exceptions in B<random places within
2196 your application stack> - this module may be to blame:
2198 Operation "ne": no method found,
2199 left argument in overloaded package <something>,
2200 right argument in overloaded package <something>
2204 Stub found while resolving method "???" overloading """" in package <something>
2206 If you fall victim to the above - please attempt to reduce the problem
2207 to something that could be sent to the L<SQL::Abstract developers
2208 |DBIx::Class/GETTING HELP/SUPPORT>
2209 (either publicly or privately). As a workaround in the meantime you can
2210 set C<$ENV{SQLA_ISVALUE_IGNORE_AUTOGENERATED_STRINGIFICATION}> to a true
2211 value, which will most likely eliminate your problem (at the expense of
2212 not being able to properly detect exotic forms of stringification).
2214 This notice and environment variable will be removed in a future version,
2215 as soon as the underlying problem is found and a reliable workaround is
2220 =head2 is_literal_value
2222 Determines if the supplied argument is a literal value as understood by this
2227 =item * C<\$sql_string>
2229 =item * C<\[ $sql_string, @bind_values ]>
2233 On failure returns C<undef>, on sucess returns an B<array> reference
2234 containing the unpacked version of the supplied literal SQL and bind values.
2236 =head1 WHERE CLAUSES
2240 This module uses a variation on the idea from L<DBIx::Abstract>. It
2241 is B<NOT>, repeat I<not> 100% compatible. B<The main logic of this
2242 module is that things in arrays are OR'ed, and things in hashes
2245 The easiest way to explain is to show lots of examples. After
2246 each C<%where> hash shown, it is assumed you used:
2248 my($stmt, @bind) = $sql->where(\%where);
2250 However, note that the C<%where> hash can be used directly in any
2251 of the other functions as well, as described above.
2253 =head2 Key-value pairs
2255 So, let's get started. To begin, a simple hash:
2259 status => 'completed'
2262 Is converted to SQL C<key = val> statements:
2264 $stmt = "WHERE user = ? AND status = ?";
2265 @bind = ('nwiger', 'completed');
2267 One common thing I end up doing is having a list of values that
2268 a field can be in. To do this, simply specify a list inside of
2273 status => ['assigned', 'in-progress', 'pending'];
2276 This simple code will create the following:
2278 $stmt = "WHERE user = ? AND ( status = ? OR status = ? OR status = ? )";
2279 @bind = ('nwiger', 'assigned', 'in-progress', 'pending');
2281 A field associated to an empty arrayref will be considered a
2282 logical false and will generate 0=1.
2284 =head2 Tests for NULL values
2286 If the value part is C<undef> then this is converted to SQL <IS NULL>
2295 $stmt = "WHERE user = ? AND status IS NULL";
2298 To test if a column IS NOT NULL:
2302 status => { '!=', undef },
2305 =head2 Specific comparison operators
2307 If you want to specify a different type of operator for your comparison,
2308 you can use a hashref for a given column:
2312 status => { '!=', 'completed' }
2315 Which would generate:
2317 $stmt = "WHERE user = ? AND status != ?";
2318 @bind = ('nwiger', 'completed');
2320 To test against multiple values, just enclose the values in an arrayref:
2322 status => { '=', ['assigned', 'in-progress', 'pending'] };
2324 Which would give you:
2326 "WHERE status = ? OR status = ? OR status = ?"
2329 The hashref can also contain multiple pairs, in which case it is expanded
2330 into an C<AND> of its elements:
2334 status => { '!=', 'completed', -not_like => 'pending%' }
2337 # Or more dynamically, like from a form
2338 $where{user} = 'nwiger';
2339 $where{status}{'!='} = 'completed';
2340 $where{status}{'-not_like'} = 'pending%';
2342 # Both generate this
2343 $stmt = "WHERE user = ? AND status != ? AND status NOT LIKE ?";
2344 @bind = ('nwiger', 'completed', 'pending%');
2347 To get an OR instead, you can combine it with the arrayref idea:
2351 priority => [ { '=', 2 }, { '>', 5 } ]
2354 Which would generate:
2356 $stmt = "WHERE ( priority = ? OR priority > ? ) AND user = ?";
2357 @bind = ('2', '5', 'nwiger');
2359 If you want to include literal SQL (with or without bind values), just use a
2360 scalar reference or reference to an arrayref as the value:
2363 date_entered => { '>' => \["to_date(?, 'MM/DD/YYYY')", "11/26/2008"] },
2364 date_expires => { '<' => \"now()" }
2367 Which would generate:
2369 $stmt = "WHERE date_entered > to_date(?, 'MM/DD/YYYY') AND date_expires < now()";
2370 @bind = ('11/26/2008');
2373 =head2 Logic and nesting operators
2375 In the example above,
2376 there is a subtle trap if you want to say something like
2377 this (notice the C<AND>):
2379 WHERE priority != ? AND priority != ?
2381 Because, in Perl you I<can't> do this:
2383 priority => { '!=' => 2, '!=' => 1 }
2385 As the second C<!=> key will obliterate the first. The solution
2386 is to use the special C<-modifier> form inside an arrayref:
2388 priority => [ -and => {'!=', 2},
2392 Normally, these would be joined by C<OR>, but the modifier tells it
2393 to use C<AND> instead. (Hint: You can use this in conjunction with the
2394 C<logic> option to C<new()> in order to change the way your queries
2395 work by default.) B<Important:> Note that the C<-modifier> goes
2396 B<INSIDE> the arrayref, as an extra first element. This will
2397 B<NOT> do what you think it might:
2399 priority => -and => [{'!=', 2}, {'!=', 1}] # WRONG!
2401 Here is a quick list of equivalencies, since there is some overlap:
2404 status => {'!=', 'completed', 'not like', 'pending%' }
2405 status => [ -and => {'!=', 'completed'}, {'not like', 'pending%'}]
2408 status => {'=', ['assigned', 'in-progress']}
2409 status => [ -or => {'=', 'assigned'}, {'=', 'in-progress'}]
2410 status => [ {'=', 'assigned'}, {'=', 'in-progress'} ]
2414 =head2 Special operators : IN, BETWEEN, etc.
2416 You can also use the hashref format to compare a list of fields using the
2417 C<IN> comparison operator, by specifying the list as an arrayref:
2420 status => 'completed',
2421 reportid => { -in => [567, 2335, 2] }
2424 Which would generate:
2426 $stmt = "WHERE status = ? AND reportid IN (?,?,?)";
2427 @bind = ('completed', '567', '2335', '2');
2429 The reverse operator C<-not_in> generates SQL C<NOT IN> and is used in
2432 If the argument to C<-in> is an empty array, 'sqlfalse' is generated
2433 (by default : C<1=0>). Similarly, C<< -not_in => [] >> generates
2434 'sqltrue' (by default : C<1=1>).
2436 In addition to the array you can supply a chunk of literal sql or
2437 literal sql with bind:
2440 customer => { -in => \[
2441 'SELECT cust_id FROM cust WHERE balance > ?',
2444 status => { -in => \'SELECT status_codes FROM states' },
2450 customer IN ( SELECT cust_id FROM cust WHERE balance > ? )
2451 AND status IN ( SELECT status_codes FROM states )
2455 Finally, if the argument to C<-in> is not a reference, it will be
2456 treated as a single-element array.
2458 Another pair of operators is C<-between> and C<-not_between>,
2459 used with an arrayref of two values:
2463 completion_date => {
2464 -not_between => ['2002-10-01', '2003-02-06']
2470 WHERE user = ? AND completion_date NOT BETWEEN ( ? AND ? )
2472 Just like with C<-in> all plausible combinations of literal SQL
2476 start0 => { -between => [ 1, 2 ] },
2477 start1 => { -between => \["? AND ?", 1, 2] },
2478 start2 => { -between => \"lower(x) AND upper(y)" },
2479 start3 => { -between => [
2481 \["upper(?)", 'stuff' ],
2488 ( start0 BETWEEN ? AND ? )
2489 AND ( start1 BETWEEN ? AND ? )
2490 AND ( start2 BETWEEN lower(x) AND upper(y) )
2491 AND ( start3 BETWEEN lower(x) AND upper(?) )
2493 @bind = (1, 2, 1, 2, 'stuff');
2496 These are the two builtin "special operators"; but the
2497 list can be expanded : see section L</"SPECIAL OPERATORS"> below.
2499 =head2 Unary operators: bool
2501 If you wish to test against boolean columns or functions within your
2502 database you can use the C<-bool> and C<-not_bool> operators. For
2503 example to test the column C<is_user> being true and the column
2504 C<is_enabled> being false you would use:-
2508 -not_bool => 'is_enabled',
2513 WHERE is_user AND NOT is_enabled
2515 If a more complex combination is required, testing more conditions,
2516 then you should use the and/or operators:-
2521 -not_bool => { two=> { -rlike => 'bar' } },
2522 -not_bool => { three => [ { '=', 2 }, { '>', 5 } ] },
2533 (NOT ( three = ? OR three > ? ))
2536 =head2 Nested conditions, -and/-or prefixes
2538 So far, we've seen how multiple conditions are joined with a top-level
2539 C<AND>. We can change this by putting the different conditions we want in
2540 hashes and then putting those hashes in an array. For example:
2545 status => { -like => ['pending%', 'dispatched'] },
2549 status => 'unassigned',
2553 This data structure would create the following:
2555 $stmt = "WHERE ( user = ? AND ( status LIKE ? OR status LIKE ? ) )
2556 OR ( user = ? AND status = ? ) )";
2557 @bind = ('nwiger', 'pending', 'dispatched', 'robot', 'unassigned');
2560 Clauses in hashrefs or arrayrefs can be prefixed with an C<-and> or C<-or>
2561 to change the logic inside :
2567 -and => [ workhrs => {'>', 20}, geo => 'ASIA' ],
2568 -or => { workhrs => {'<', 50}, geo => 'EURO' },
2575 $stmt = "WHERE ( user = ?
2576 AND ( ( workhrs > ? AND geo = ? )
2577 OR ( workhrs < ? OR geo = ? ) ) )";
2578 @bind = ('nwiger', '20', 'ASIA', '50', 'EURO');
2580 =head3 Algebraic inconsistency, for historical reasons
2582 C<Important note>: when connecting several conditions, the C<-and->|C<-or>
2583 operator goes C<outside> of the nested structure; whereas when connecting
2584 several constraints on one column, the C<-and> operator goes
2585 C<inside> the arrayref. Here is an example combining both features :
2588 -and => [a => 1, b => 2],
2589 -or => [c => 3, d => 4],
2590 e => [-and => {-like => 'foo%'}, {-like => '%bar'} ]
2595 WHERE ( ( ( a = ? AND b = ? )
2596 OR ( c = ? OR d = ? )
2597 OR ( e LIKE ? AND e LIKE ? ) ) )
2599 This difference in syntax is unfortunate but must be preserved for
2600 historical reasons. So be careful : the two examples below would
2601 seem algebraically equivalent, but they are not
2603 {col => [-and => {-like => 'foo%'}, {-like => '%bar'}]}
2604 # yields : WHERE ( ( col LIKE ? AND col LIKE ? ) )
2606 [-and => {col => {-like => 'foo%'}, {col => {-like => '%bar'}}]]
2607 # yields : WHERE ( ( col LIKE ? OR col LIKE ? ) )
2610 =head2 Literal SQL and value type operators
2612 The basic premise of SQL::Abstract is that in WHERE specifications the "left
2613 side" is a column name and the "right side" is a value (normally rendered as
2614 a placeholder). This holds true for both hashrefs and arrayref pairs as you
2615 see in the L</WHERE CLAUSES> examples above. Sometimes it is necessary to
2616 alter this behavior. There are several ways of doing so.
2620 This is a virtual operator that signals the string to its right side is an
2621 identifier (a column name) and not a value. For example to compare two
2622 columns you would write:
2625 priority => { '<', 2 },
2626 requestor => { -ident => 'submitter' },
2631 $stmt = "WHERE priority < ? AND requestor = submitter";
2634 If you are maintaining legacy code you may see a different construct as
2635 described in L</Deprecated usage of Literal SQL>, please use C<-ident> in new
2640 This is a virtual operator that signals that the construct to its right side
2641 is a value to be passed to DBI. This is for example necessary when you want
2642 to write a where clause against an array (for RDBMS that support such
2643 datatypes). For example:
2646 array => { -value => [1, 2, 3] }
2651 $stmt = 'WHERE array = ?';
2652 @bind = ([1, 2, 3]);
2654 Note that if you were to simply say:
2660 the result would probably not be what you wanted:
2662 $stmt = 'WHERE array = ? OR array = ? OR array = ?';
2667 Finally, sometimes only literal SQL will do. To include a random snippet
2668 of SQL verbatim, you specify it as a scalar reference. Consider this only
2669 as a last resort. Usually there is a better way. For example:
2672 priority => { '<', 2 },
2673 requestor => { -in => \'(SELECT name FROM hitmen)' },
2678 $stmt = "WHERE priority < ? AND requestor IN (SELECT name FROM hitmen)"
2681 Note that in this example, you only get one bind parameter back, since
2682 the verbatim SQL is passed as part of the statement.
2686 Never use untrusted input as a literal SQL argument - this is a massive
2687 security risk (there is no way to check literal snippets for SQL
2688 injections and other nastyness). If you need to deal with untrusted input
2689 use literal SQL with placeholders as described next.
2691 =head3 Literal SQL with placeholders and bind values (subqueries)
2693 If the literal SQL to be inserted has placeholders and bind values,
2694 use a reference to an arrayref (yes this is a double reference --
2695 not so common, but perfectly legal Perl). For example, to find a date
2696 in Postgres you can use something like this:
2699 date_column => \[ "= date '2008-09-30' - ?::integer", 10 ]
2704 $stmt = "WHERE ( date_column = date '2008-09-30' - ?::integer )"
2707 Note that you must pass the bind values in the same format as they are returned
2708 by L<where|/where(\%where, \@order)>. This means that if you set L</bindtype>
2709 to C<columns>, you must provide the bind values in the
2710 C<< [ column_meta => value ] >> format, where C<column_meta> is an opaque
2711 scalar value; most commonly the column name, but you can use any scalar value
2712 (including references and blessed references), L<SQL::Abstract> will simply
2713 pass it through intact. So if C<bindtype> is set to C<columns> the above
2714 example will look like:
2717 date_column => \[ "= date '2008-09-30' - ?::integer", [ {} => 10 ] ]
2720 Literal SQL is especially useful for nesting parenthesized clauses in the
2721 main SQL query. Here is a first example :
2723 my ($sub_stmt, @sub_bind) = ("SELECT c1 FROM t1 WHERE c2 < ? AND c3 LIKE ?",
2727 bar => \["IN ($sub_stmt)" => @sub_bind],
2732 $stmt = "WHERE (foo = ? AND bar IN (SELECT c1 FROM t1
2733 WHERE c2 < ? AND c3 LIKE ?))";
2734 @bind = (1234, 100, "foo%");
2736 Other subquery operators, like for example C<"E<gt> ALL"> or C<"NOT IN">,
2737 are expressed in the same way. Of course the C<$sub_stmt> and
2738 its associated bind values can be generated through a former call
2741 my ($sub_stmt, @sub_bind)
2742 = $sql->select("t1", "c1", {c2 => {"<" => 100},
2743 c3 => {-like => "foo%"}});
2746 bar => \["> ALL ($sub_stmt)" => @sub_bind],
2749 In the examples above, the subquery was used as an operator on a column;
2750 but the same principle also applies for a clause within the main C<%where>
2751 hash, like an EXISTS subquery :
2753 my ($sub_stmt, @sub_bind)
2754 = $sql->select("t1", "*", {c1 => 1, c2 => \"> t0.c0"});
2755 my %where = ( -and => [
2757 \["EXISTS ($sub_stmt)" => @sub_bind],
2762 $stmt = "WHERE (foo = ? AND EXISTS (SELECT * FROM t1
2763 WHERE c1 = ? AND c2 > t0.c0))";
2767 Observe that the condition on C<c2> in the subquery refers to
2768 column C<t0.c0> of the main query : this is I<not> a bind
2769 value, so we have to express it through a scalar ref.
2770 Writing C<< c2 => {">" => "t0.c0"} >> would have generated
2771 C<< c2 > ? >> with bind value C<"t0.c0"> ... not exactly
2772 what we wanted here.
2774 Finally, here is an example where a subquery is used
2775 for expressing unary negation:
2777 my ($sub_stmt, @sub_bind)
2778 = $sql->where({age => [{"<" => 10}, {">" => 20}]});
2779 $sub_stmt =~ s/^ where //i; # don't want "WHERE" in the subclause
2781 lname => {like => '%son%'},
2782 \["NOT ($sub_stmt)" => @sub_bind],
2787 $stmt = "lname LIKE ? AND NOT ( age < ? OR age > ? )"
2788 @bind = ('%son%', 10, 20)
2790 =head3 Deprecated usage of Literal SQL
2792 Below are some examples of archaic use of literal SQL. It is shown only as
2793 reference for those who deal with legacy code. Each example has a much
2794 better, cleaner and safer alternative that users should opt for in new code.
2800 my %where = ( requestor => \'IS NOT NULL' )
2802 $stmt = "WHERE requestor IS NOT NULL"
2804 This used to be the way of generating NULL comparisons, before the handling
2805 of C<undef> got formalized. For new code please use the superior syntax as
2806 described in L</Tests for NULL values>.
2810 my %where = ( requestor => \'= submitter' )
2812 $stmt = "WHERE requestor = submitter"
2814 This used to be the only way to compare columns. Use the superior L</-ident>
2815 method for all new code. For example an identifier declared in such a way
2816 will be properly quoted if L</quote_char> is properly set, while the legacy
2817 form will remain as supplied.
2821 my %where = ( is_ready => \"", completed => { '>', '2012-12-21' } )
2823 $stmt = "WHERE completed > ? AND is_ready"
2824 @bind = ('2012-12-21')
2826 Using an empty string literal used to be the only way to express a boolean.
2827 For all new code please use the much more readable
2828 L<-bool|/Unary operators: bool> operator.
2834 These pages could go on for a while, since the nesting of the data
2835 structures this module can handle are pretty much unlimited (the
2836 module implements the C<WHERE> expansion as a recursive function
2837 internally). Your best bet is to "play around" with the module a
2838 little to see how the data structures behave, and choose the best
2839 format for your data based on that.
2841 And of course, all the values above will probably be replaced with
2842 variables gotten from forms or the command line. After all, if you
2843 knew everything ahead of time, you wouldn't have to worry about
2844 dynamically-generating SQL and could just hardwire it into your
2847 =head1 ORDER BY CLAUSES
2849 Some functions take an order by clause. This can either be a scalar (just a
2850 column name,) a hash of C<< { -desc => 'col' } >> or C<< { -asc => 'col' } >>,
2851 or an array of either of the two previous forms. Examples:
2853 Given | Will Generate
2854 ----------------------------------------------------------
2856 \'colA DESC' | ORDER BY colA DESC
2858 'colA' | ORDER BY colA
2860 [qw/colA colB/] | ORDER BY colA, colB
2862 {-asc => 'colA'} | ORDER BY colA ASC
2864 {-desc => 'colB'} | ORDER BY colB DESC
2866 ['colA', {-asc => 'colB'}] | ORDER BY colA, colB ASC
2868 { -asc => [qw/colA colB/] } | ORDER BY colA ASC, colB ASC
2871 { -asc => 'colA' }, | ORDER BY colA ASC, colB DESC,
2872 { -desc => [qw/colB/], | colC ASC, colD ASC
2873 { -asc => [qw/colC colD/],|
2875 ===========================================================
2879 =head1 SPECIAL OPERATORS
2881 my $sqlmaker = SQL::Abstract->new(special_ops => [
2885 my ($self, $field, $op, $arg) = @_;
2891 handler => 'method_name',
2895 A "special operator" is a SQL syntactic clause that can be
2896 applied to a field, instead of a usual binary operator.
2899 WHERE field IN (?, ?, ?)
2900 WHERE field BETWEEN ? AND ?
2901 WHERE MATCH(field) AGAINST (?, ?)
2903 Special operators IN and BETWEEN are fairly standard and therefore
2904 are builtin within C<SQL::Abstract> (as the overridable methods
2905 C<_where_field_IN> and C<_where_field_BETWEEN>). For other operators,
2906 like the MATCH .. AGAINST example above which is specific to MySQL,
2907 you can write your own operator handlers - supply a C<special_ops>
2908 argument to the C<new> method. That argument takes an arrayref of
2909 operator definitions; each operator definition is a hashref with two
2916 the regular expression to match the operator
2920 Either a coderef or a plain scalar method name. In both cases
2921 the expected return is C<< ($sql, @bind) >>.
2923 When supplied with a method name, it is simply called on the
2924 L<SQL::Abstract> object as:
2926 $self->$method_name ($field, $op, $arg)
2930 $field is the LHS of the operator
2931 $op is the part that matched the handler regex
2934 When supplied with a coderef, it is called as:
2936 $coderef->($self, $field, $op, $arg)
2941 For example, here is an implementation
2942 of the MATCH .. AGAINST syntax for MySQL
2944 my $sqlmaker = SQL::Abstract->new(special_ops => [
2946 # special op for MySql MATCH (field) AGAINST(word1, word2, ...)
2947 {regex => qr/^match$/i,
2949 my ($self, $field, $op, $arg) = @_;
2950 $arg = [$arg] if not ref $arg;
2951 my $label = $self->_quote($field);
2952 my ($placeholder) = $self->_convert('?');
2953 my $placeholders = join ", ", (($placeholder) x @$arg);
2954 my $sql = $self->_sqlcase('match') . " ($label) "
2955 . $self->_sqlcase('against') . " ($placeholders) ";
2956 my @bind = $self->_bindtype($field, @$arg);
2957 return ($sql, @bind);
2964 =head1 UNARY OPERATORS
2966 my $sqlmaker = SQL::Abstract->new(unary_ops => [
2970 my ($self, $op, $arg) = @_;
2976 handler => 'method_name',
2980 A "unary operator" is a SQL syntactic clause that can be
2981 applied to a field - the operator goes before the field
2983 You can write your own operator handlers - supply a C<unary_ops>
2984 argument to the C<new> method. That argument takes an arrayref of
2985 operator definitions; each operator definition is a hashref with two
2992 the regular expression to match the operator
2996 Either a coderef or a plain scalar method name. In both cases
2997 the expected return is C<< $sql >>.
2999 When supplied with a method name, it is simply called on the
3000 L<SQL::Abstract> object as:
3002 $self->$method_name ($op, $arg)
3006 $op is the part that matched the handler regex
3007 $arg is the RHS or argument of the operator
3009 When supplied with a coderef, it is called as:
3011 $coderef->($self, $op, $arg)
3019 Thanks to some benchmarking by Mark Stosberg, it turns out that
3020 this module is many orders of magnitude faster than using C<DBIx::Abstract>.
3021 I must admit this wasn't an intentional design issue, but it's a
3022 byproduct of the fact that you get to control your C<DBI> handles
3025 To maximize performance, use a code snippet like the following:
3027 # prepare a statement handle using the first row
3028 # and then reuse it for the rest of the rows
3030 for my $href (@array_of_hashrefs) {
3031 $stmt ||= $sql->insert('table', $href);
3032 $sth ||= $dbh->prepare($stmt);
3033 $sth->execute($sql->values($href));
3036 The reason this works is because the keys in your C<$href> are sorted
3037 internally by B<SQL::Abstract>. Thus, as long as your data retains
3038 the same structure, you only have to generate the SQL the first time
3039 around. On subsequent queries, simply use the C<values> function provided
3040 by this module to return your values in the correct order.
3042 However this depends on the values having the same type - if, for
3043 example, the values of a where clause may either have values
3044 (resulting in sql of the form C<column = ?> with a single bind
3045 value), or alternatively the values might be C<undef> (resulting in
3046 sql of the form C<column IS NULL> with no bind value) then the
3047 caching technique suggested will not work.
3051 If you use my C<CGI::FormBuilder> module at all, you'll hopefully
3052 really like this part (I do, at least). Building up a complex query
3053 can be as simple as the following:
3060 use CGI::FormBuilder;
3063 my $form = CGI::FormBuilder->new(...);
3064 my $sql = SQL::Abstract->new;
3066 if ($form->submitted) {
3067 my $field = $form->field;
3068 my $id = delete $field->{id};
3069 my($stmt, @bind) = $sql->update('table', $field, {id => $id});
3072 Of course, you would still have to connect using C<DBI> to run the
3073 query, but the point is that if you make your form look like your
3074 table, the actual query script can be extremely simplistic.
3076 If you're B<REALLY> lazy (I am), check out C<HTML::QuickTable> for
3077 a fast interface to returning and formatting data. I frequently
3078 use these three modules together to write complex database query
3079 apps in under 50 lines.
3081 =head1 HOW TO CONTRIBUTE
3083 Contributions are always welcome, in all usable forms (we especially
3084 welcome documentation improvements). The delivery methods include git-
3085 or unified-diff formatted patches, GitHub pull requests, or plain bug
3086 reports either via RT or the Mailing list. Contributors are generally
3087 granted full access to the official repository after their first several
3088 patches pass successful review.
3090 This project is maintained in a git repository. The code and related tools are
3091 accessible at the following locations:
3095 =item * Official repo: L<git://git.shadowcat.co.uk/dbsrgits/SQL-Abstract.git>
3097 =item * Official gitweb: L<http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/SQL-Abstract.git>
3099 =item * GitHub mirror: L<https://github.com/dbsrgits/sql-abstract>
3101 =item * Authorized committers: L<ssh://dbsrgits@git.shadowcat.co.uk/SQL-Abstract.git>
3107 Version 1.50 was a major internal refactoring of C<SQL::Abstract>.
3108 Great care has been taken to preserve the I<published> behavior
3109 documented in previous versions in the 1.* family; however,
3110 some features that were previously undocumented, or behaved
3111 differently from the documentation, had to be changed in order
3112 to clarify the semantics. Hence, client code that was relying
3113 on some dark areas of C<SQL::Abstract> v1.*
3114 B<might behave differently> in v1.50.
3116 The main changes are :
3122 support for literal SQL through the C<< \ [ $sql, @bind ] >> syntax.
3126 support for the { operator => \"..." } construct (to embed literal SQL)
3130 support for the { operator => \["...", @bind] } construct (to embed literal SQL with bind values)
3134 optional support for L<array datatypes|/"Inserting and Updating Arrays">
3138 defensive programming : check arguments
3142 fixed bug with global logic, which was previously implemented
3143 through global variables yielding side-effects. Prior versions would
3144 interpret C<< [ {cond1, cond2}, [cond3, cond4] ] >>
3145 as C<< "(cond1 AND cond2) OR (cond3 AND cond4)" >>.
3146 Now this is interpreted
3147 as C<< "(cond1 AND cond2) OR (cond3 OR cond4)" >>.
3152 fixed semantics of _bindtype on array args
3156 dropped the C<_anoncopy> of the %where tree. No longer necessary,
3157 we just avoid shifting arrays within that tree.
3161 dropped the C<_modlogic> function
3165 =head1 ACKNOWLEDGEMENTS
3167 There are a number of individuals that have really helped out with
3168 this module. Unfortunately, most of them submitted bugs via CPAN
3169 so I have no idea who they are! But the people I do know are:
3171 Ash Berlin (order_by hash term support)
3172 Matt Trout (DBIx::Class support)
3173 Mark Stosberg (benchmarking)
3174 Chas Owens (initial "IN" operator support)
3175 Philip Collins (per-field SQL functions)
3176 Eric Kolve (hashref "AND" support)
3177 Mike Fragassi (enhancements to "BETWEEN" and "LIKE")
3178 Dan Kubb (support for "quote_char" and "name_sep")
3179 Guillermo Roditi (patch to cleanup "IN" and "BETWEEN", fix and tests for _order_by)
3180 Laurent Dami (internal refactoring, extensible list of special operators, literal SQL)
3181 Norbert Buchmuller (support for literal SQL in hashpair, misc. fixes & tests)
3182 Peter Rabbitson (rewrite of SQLA::Test, misc. fixes & tests)
3183 Oliver Charles (support for "RETURNING" after "INSERT")
3189 L<DBIx::Class>, L<DBIx::Abstract>, L<CGI::FormBuilder>, L<HTML::QuickTable>.
3193 Copyright (c) 2001-2007 Nathan Wiger <nwiger@cpan.org>. All Rights Reserved.
3195 This module is actively maintained by Matt Trout <mst@shadowcatsystems.co.uk>
3197 For support, your best bet is to try the C<DBIx::Class> users mailing list.
3198 While not an official support venue, C<DBIx::Class> makes heavy use of
3199 C<SQL::Abstract>, and as such list members there are very familiar with
3200 how to create queries.
3204 This module is free software; you may copy this under the same
3205 terms as perl itself (either the GNU General Public License or
3206 the Artistic License)