Applied patch from kados regarding use of a DateTime::Format class to validate
[dbsrgits/DBIx-Class-Historic.git] / lib / DBIx / Class / SQLAHacks.pm
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6f4ddea1 1package # Hide from PAUSE
855c6fd0 2 DBIx::Class::SQLAHacks;
6f4ddea1 3
998373c2 4# This module is a subclass of SQL::Abstract::Limit and includes a number
5# of DBIC-specific workarounds, not yet suitable for inclusion into the
6# SQLA core
7
6f4ddea1 8use base qw/SQL::Abstract::Limit/;
e3764383 9use strict;
10use warnings;
b2b22cd6 11use Carp::Clan qw/^DBIx::Class|^SQL::Abstract/;
12
13BEGIN {
14 # reinstall the carp()/croak() functions imported into SQL::Abstract
15 # as Carp and Carp::Clan do not like each other much
16 no warnings qw/redefine/;
17 no strict qw/refs/;
18 for my $f (qw/carp croak/) {
329d7385 19
b2b22cd6 20 my $orig = \&{"SQL::Abstract::$f"};
21 *{"SQL::Abstract::$f"} = sub {
22
23 local $Carp::CarpLevel = 1; # even though Carp::Clan ignores this, $orig will not
24
329d7385 25 if (Carp::longmess() =~ /DBIx::Class::SQLAHacks::[\w]+ .+? called \s at/x) {
b2b22cd6 26 __PACKAGE__->can($f)->(@_);
27 }
28 else {
29 $orig->(@_);
30 }
31 }
32 }
33}
6f4ddea1 34
998373c2 35
36# Tries to determine limit dialect.
37#
6f4ddea1 38sub new {
39 my $self = shift->SUPER::new(@_);
40
41 # This prevents the caching of $dbh in S::A::L, I believe
42 # If limit_dialect is a ref (like a $dbh), go ahead and replace
43 # it with what it resolves to:
44 $self->{limit_dialect} = $self->_find_syntax($self->{limit_dialect})
45 if ref $self->{limit_dialect};
46
47 $self;
48}
49
6f4ddea1 50# Some databases (sqlite) do not handle multiple parenthesis
998373c2 51# around in/between arguments. A tentative x IN ( (1, 2 ,3) )
6f4ddea1 52# is interpreted as x IN 1 or something similar.
53#
54# Since we currently do not have access to the SQLA AST, resort
55# to barbaric mutilation of any SQL supplied in literal form
6f4ddea1 56sub _strip_outer_paren {
57 my ($self, $arg) = @_;
58
59 return $self->_SWITCH_refkind ($arg, {
60 ARRAYREFREF => sub {
61 $$arg->[0] = __strip_outer_paren ($$arg->[0]);
62 return $arg;
63 },
64 SCALARREF => sub {
65 return \__strip_outer_paren( $$arg );
66 },
67 FALLBACK => sub {
68 return $arg
69 },
70 });
71}
72
73sub __strip_outer_paren {
74 my $sql = shift;
75
76 if ($sql and not ref $sql) {
77 while ($sql =~ /^ \s* \( (.*) \) \s* $/x ) {
78 $sql = $1;
79 }
80 }
81
82 return $sql;
83}
84
85sub _where_field_IN {
86 my ($self, $lhs, $op, $rhs) = @_;
87 $rhs = $self->_strip_outer_paren ($rhs);
88 return $self->SUPER::_where_field_IN ($lhs, $op, $rhs);
89}
90
91sub _where_field_BETWEEN {
92 my ($self, $lhs, $op, $rhs) = @_;
93 $rhs = $self->_strip_outer_paren ($rhs);
94 return $self->SUPER::_where_field_BETWEEN ($lhs, $op, $rhs);
95}
96
15827712 97# Slow but ANSI standard Limit/Offset support. DB2 uses this
6f4ddea1 98sub _RowNumberOver {
99 my ($self, $sql, $order, $rows, $offset ) = @_;
100
101 $offset += 1;
03e1d9af 102 my $last = $rows + $offset - 1;
6f4ddea1 103 my ( $order_by ) = $self->_order_by( $order );
104
105 $sql = <<"SQL";
106SELECT * FROM
107(
108 SELECT Q1.*, ROW_NUMBER() OVER( ) AS ROW_NUM FROM (
109 $sql
110 $order_by
111 ) Q1
112) Q2
113WHERE ROW_NUM BETWEEN $offset AND $last
114
115SQL
116
117 return $sql;
118}
119
15827712 120# Crappy Top based Limit/Offset support. MSSQL uses this currently,
121# but may have to switch to RowNumberOver one day
122sub _Top {
123 my ( $self, $sql, $order, $rows, $offset ) = @_;
124
b1e1d073 125 # mangle the input sql so it can be properly aliased in the outer queries
126 $sql =~ s/^ \s* SELECT \s+ (.+?) \s+ (?=FROM)//ix
127 or croak "Unrecognizable SELECT: $sql";
42e5b103 128 my $sql_select = $1;
129 my @sql_select = split (/\s*,\s*/, $sql_select);
130
131 # we can't support subqueries (in fact MSSQL can't) - croak
132 if (@sql_select != @{$self->{_dbic_rs_attrs}{select}}) {
133 croak (sprintf (
134 'SQL SELECT did not parse cleanly - retrieved %d comma separated elements, while '
135 . 'the resultset select attribure contains %d elements: %s',
136 scalar @sql_select,
137 scalar @{$self->{_dbic_rs_attrs}{select}},
138 $sql_select,
139 ));
140 }
b1e1d073 141
42e5b103 142 my $name_sep = $self->name_sep || '.';
ac93965c 143 my $esc_name_sep = "\Q$name_sep\E";
144 my $col_re = qr/ ^ (?: (.+) $esc_name_sep )? ([^$esc_name_sep]+) $ /x;
145
146 my $rs_alias = $self->{_dbic_rs_attrs}{alias};
147 my $quoted_rs_alias = $self->_quote ($rs_alias);
b1e1d073 148
42e5b103 149 # construct the new select lists, rename(alias) some columns if necessary
150 my (@outer_select, @inner_select, %seen_names, %col_aliases, %outer_col_aliases);
b1e1d073 151
42e5b103 152 for (@{$self->{_dbic_rs_attrs}{select}}) {
153 next if ref $_;
154 my ($table, $orig_colname) = ( $_ =~ $col_re );
155 next unless $table;
156 $seen_names{$orig_colname}++;
157 }
b1e1d073 158
42e5b103 159 for my $i (0 .. $#sql_select) {
b1e1d073 160
42e5b103 161 my $colsel_arg = $self->{_dbic_rs_attrs}{select}[$i];
162 my $colsel_sql = $sql_select[$i];
b1e1d073 163
42e5b103 164 # this may or may not work (in case of a scalarref or something)
165 my ($table, $orig_colname) = ( $colsel_arg =~ $col_re );
b1e1d073 166
42e5b103 167 my $quoted_alias;
168 # do not attempt to understand non-scalar selects - alias numerically
169 if (ref $colsel_arg) {
170 $quoted_alias = $self->_quote ('column_' . (@inner_select + 1) );
171 }
172 # column name seen more than once - alias it
173 elsif ($orig_colname && ($seen_names{$orig_colname} > 1) ) {
174 $quoted_alias = $self->_quote ("${table}__${orig_colname}");
175 }
b1e1d073 176
42e5b103 177 # we did rename - make a record and adjust
178 if ($quoted_alias) {
179 # alias inner
180 push @inner_select, "$colsel_sql AS $quoted_alias";
181
182 # push alias to outer
183 push @outer_select, $quoted_alias;
184
185 # Any aliasing accumulated here will be considered
186 # both for inner and outer adjustments of ORDER BY
187 $self->__record_alias (
188 \%col_aliases,
189 $quoted_alias,
190 $colsel_arg,
191 $table ? $orig_colname : undef,
192 );
b1e1d073 193 }
194
42e5b103 195 # otherwise just leave things intact inside, and use the abbreviated one outside
196 # (as we do not have table names anymore)
197 else {
198 push @inner_select, $colsel_sql;
199
200 my $outer_quoted = $self->_quote ($orig_colname); # it was not a duplicate so should just work
201 push @outer_select, $outer_quoted;
202 $self->__record_alias (
203 \%outer_col_aliases,
204 $outer_quoted,
205 $colsel_arg,
206 $table ? $orig_colname : undef,
207 );
208 }
b1e1d073 209 }
210
211 my $outer_select = join (', ', @outer_select );
42e5b103 212 my $inner_select = join (', ', @inner_select );
b1e1d073 213
42e5b103 214 %outer_col_aliases = (%outer_col_aliases, %col_aliases);
b1e1d073 215
216 # deal with order
15827712 217 croak '$order supplied to SQLAHacks limit emulators must be a hash'
218 if (ref $order ne 'HASH');
219
8f6dbee9 220 $order = { %$order }; #copy
221
02d133f0 222 my $req_order = $order->{order_by};
e2db8319 223
224 # examine normalized version, collapses nesting
225 my $limit_order;
226 if (scalar $self->_order_by_chunks ($req_order)) {
227 $limit_order = $req_order;
228 }
229 else {
e2db8319 230 $limit_order = [ map
231 { join ('', $rs_alias, $name_sep, $_ ) }
232 ( $self->{_dbic_rs_attrs}{_source_handle}->resolve->primary_columns )
233 ];
234 }
b1e1d073 235
42e5b103 236 my ( $order_by_inner, $order_by_outer ) = $self->_order_directions($limit_order);
237 my $order_by_requested = $self->_order_by ($req_order);
15827712 238
64c7c000 239 # generate the rest
e2db8319 240 delete $order->{order_by};
64c7c000 241 my $grpby_having = $self->_order_by ($order);
242
243 # short circuit for counts - the ordering complexity is needless
244 if ($self->{_dbic_rs_attrs}{-for_count_only}) {
245 return "SELECT TOP $rows $inner_select $sql $grpby_having $order_by_outer";
246 }
247
42e5b103 248 # we can't really adjust the order_by columns, as introspection is lacking
249 # resort to simple substitution
250 for my $col (keys %outer_col_aliases) {
251 for ($order_by_requested, $order_by_outer) {
252 $_ =~ s/\s+$col\s+/ $outer_col_aliases{$col} /g;
b1e1d073 253 }
254 }
42e5b103 255 for my $col (keys %col_aliases) {
9c1ffdde 256 $order_by_inner =~ s/\s+$col\s+/ $col_aliases{$col} /g;
42e5b103 257 }
1cbd3034 258
02d133f0 259
42e5b103 260 my $inner_lim = $rows + $offset;
15827712 261
618a0fe3 262 $sql = "SELECT TOP $inner_lim $inner_select $sql $grpby_having $order_by_inner";
42e5b103 263
264 if ($offset) {
265 $sql = <<"SQL";
b1e1d073 266
267 SELECT TOP $rows $outer_select FROM
15827712 268 (
42e5b103 269 $sql
ac93965c 270 ) $quoted_rs_alias
15827712 271 $order_by_outer
b1e1d073 272SQL
273
42e5b103 274 }
15827712 275
42e5b103 276 if ($order_by_requested) {
b1e1d073 277 $sql = <<"SQL";
278
42e5b103 279 SELECT $outer_select FROM
ac93965c 280 ( $sql ) $quoted_rs_alias
281 $order_by_requested
15827712 282SQL
b1e1d073 283
284 }
285
ac93965c 286 $sql =~ s/\s*\n\s*/ /g; # parsing out multiline statements is harder than a single line
b1e1d073 287 return $sql;
15827712 288}
289
42e5b103 290# action at a distance to shorten Top code above
291sub __record_alias {
292 my ($self, $register, $alias, $fqcol, $col) = @_;
293
294 # record qualified name
295 $register->{$fqcol} = $alias;
296 $register->{$self->_quote($fqcol)} = $alias;
297
298 return unless $col;
299
b6d347e0 300 # record unqualified name, undef (no adjustment) if a duplicate is found
42e5b103 301 if (exists $register->{$col}) {
302 $register->{$col} = undef;
303 }
304 else {
305 $register->{$col} = $alias;
306 }
307
308 $register->{$self->_quote($col)} = $register->{$col};
309}
310
15827712 311
6f4ddea1 312
313# While we're at it, this should make LIMIT queries more efficient,
314# without digging into things too deeply
6f4ddea1 315sub _find_syntax {
316 my ($self, $syntax) = @_;
ac788c46 317 return $self->{_cached_syntax} ||= $self->SUPER::_find_syntax($syntax);
6f4ddea1 318}
319
ec7cfd36 320my $for_syntax = {
321 update => 'FOR UPDATE',
322 shared => 'FOR SHARE',
323};
998373c2 324# Quotes table names, handles "limit" dialects (e.g. where rownum between x and
325# y), supports SELECT ... FOR UPDATE and SELECT ... FOR SHARE.
6f4ddea1 326sub select {
327 my ($self, $table, $fields, $where, $order, @rest) = @_;
1cbd3034 328
329 $self->{"${_}_bind"} = [] for (qw/having from order/);
db56cf3d 330
6f4ddea1 331 if (ref $table eq 'SCALAR') {
332 $table = $$table;
333 }
334 elsif (not ref $table) {
335 $table = $self->_quote($table);
336 }
337 local $self->{rownum_hack_count} = 1
338 if (defined $rest[0] && $self->{limit_dialect} eq 'RowNum');
339 @rest = (-1) unless defined $rest[0];
e8fcf76f 340 croak "LIMIT 0 Does Not Compute" if $rest[0] == 0;
6f4ddea1 341 # and anyway, SQL::Abstract::Limit will cause a barf if we don't first
db56cf3d 342 my ($sql, @where_bind) = $self->SUPER::select(
6f4ddea1 343 $table, $self->_recurse_fields($fields), $where, $order, @rest
344 );
ec7cfd36 345 if (my $for = delete $self->{_dbic_rs_attrs}{for}) {
346 $sql .= " $for_syntax->{$for}" if $for_syntax->{$for};
347 }
348
1cbd3034 349 return wantarray ? ($sql, @{$self->{from_bind}}, @where_bind, @{$self->{having_bind}}, @{$self->{order_bind}} ) : $sql;
6f4ddea1 350}
351
998373c2 352# Quotes table names, and handles default inserts
6f4ddea1 353sub insert {
354 my $self = shift;
355 my $table = shift;
356 $table = $self->_quote($table) unless ref($table);
7a72e5a5 357
358 # SQLA will emit INSERT INTO $table ( ) VALUES ( )
359 # which is sadly understood only by MySQL. Change default behavior here,
360 # until SQLA2 comes with proper dialect support
361 if (! $_[0] or (ref $_[0] eq 'HASH' and !keys %{$_[0]} ) ) {
362 return "INSERT INTO ${table} DEFAULT VALUES"
363 }
364
6f4ddea1 365 $self->SUPER::insert($table, @_);
366}
367
998373c2 368# Just quotes table names.
6f4ddea1 369sub update {
370 my $self = shift;
371 my $table = shift;
372 $table = $self->_quote($table) unless ref($table);
373 $self->SUPER::update($table, @_);
374}
375
998373c2 376# Just quotes table names.
6f4ddea1 377sub delete {
378 my $self = shift;
379 my $table = shift;
380 $table = $self->_quote($table) unless ref($table);
381 $self->SUPER::delete($table, @_);
382}
383
384sub _emulate_limit {
385 my $self = shift;
386 if ($_[3] == -1) {
387 return $_[1].$self->_order_by($_[2]);
388 } else {
389 return $self->SUPER::_emulate_limit(@_);
390 }
391}
392
393sub _recurse_fields {
394 my ($self, $fields, $params) = @_;
395 my $ref = ref $fields;
396 return $self->_quote($fields) unless $ref;
397 return $$fields if $ref eq 'SCALAR';
398
399 if ($ref eq 'ARRAY') {
400 return join(', ', map {
401 $self->_recurse_fields($_)
402 .(exists $self->{rownum_hack_count} && !($params && $params->{no_rownum_hack})
403 ? ' AS col'.$self->{rownum_hack_count}++
404 : '')
405 } @$fields);
83e09b5b 406 }
407 elsif ($ref eq 'HASH') {
408 my %hash = %$fields;
409 my ($select, $as);
410
411 if ($hash{-select}) {
412 $select = $self->_recurse_fields (delete $hash{-select});
413 $as = $self->_quote (delete $hash{-as});
414 }
415 else {
416 my ($func, $args) = each %hash;
417 delete $hash{$func};
418
419 if (lc ($func) eq 'distinct' && ref $args eq 'ARRAY' && @$args > 1) {
420 croak (
421 'The select => { distinct => ... } syntax is not supported for multiple columns.'
422 .' Instead please use { group_by => [ qw/' . (join ' ', @$args) . '/ ] }'
423 .' or { select => [ qw/' . (join ' ', @$args) . '/ ], distinct => 1 }'
424 );
db56cf3d 425 }
83e09b5b 426 $select = sprintf ('%s( %s )',
427 $self->_sqlcase($func),
428 $self->_recurse_fields($args)
429 );
6f4ddea1 430 }
83e09b5b 431
432 # there should be nothing left
433 if (keys %hash) {
434 croak "Malformed select argument - too many keys in hash: " . join (',', keys %$fields );
6f4ddea1 435 }
83e09b5b 436
437 $select .= " AS $as" if $as;
438 return $select;
6f4ddea1 439 }
440 # Is the second check absolutely necessary?
441 elsif ( $ref eq 'REF' and ref($$fields) eq 'ARRAY' ) {
db56cf3d 442 return $self->_fold_sqlbind( $fields );
6f4ddea1 443 }
444 else {
e8fcf76f 445 croak($ref . qq{ unexpected in _recurse_fields()})
6f4ddea1 446 }
447}
448
449sub _order_by {
1cbd3034 450 my ($self, $arg) = @_;
15827712 451
1cbd3034 452 if (ref $arg eq 'HASH' and keys %$arg and not grep { $_ =~ /^-(?:desc|asc)/i } keys %$arg ) {
453
454 my $ret = '';
455
83e09b5b 456 if (my $g = $self->_recurse_fields($arg->{group_by}, { no_rownum_hack => 1 }) ) {
457 $ret = $self->_sqlcase(' group by ') . $g;
6f4ddea1 458 }
15827712 459
1cbd3034 460 if (defined $arg->{having}) {
461 my ($frag, @bind) = $self->_recurse_where($arg->{having});
462 push(@{$self->{having_bind}}, @bind);
6f4ddea1 463 $ret .= $self->_sqlcase(' having ').$frag;
464 }
15827712 465
1cbd3034 466 if (defined $arg->{order_by}) {
467 my ($frag, @bind) = $self->SUPER::_order_by($arg->{order_by});
468 push(@{$self->{order_bind}}, @bind);
469 $ret .= $frag;
6f4ddea1 470 }
15827712 471
1cbd3034 472 return $ret;
fde3719a 473 }
1cbd3034 474 else {
475 my ($sql, @bind) = $self->SUPER::_order_by ($arg);
476 push(@{$self->{order_bind}}, @bind);
477 return $sql;
fd4cb60a 478 }
6f4ddea1 479}
480
1cbd3034 481sub _order_directions {
fd4cb60a 482 my ($self, $order) = @_;
15827712 483
1cbd3034 484 # strip bind values - none of the current _order_directions users support them
485 return $self->SUPER::_order_directions( [ map
486 { ref $_ ? $_->[0] : $_ }
487 $self->_order_by_chunks ($order)
488 ]);
fd4cb60a 489}
490
6f4ddea1 491sub _table {
492 my ($self, $from) = @_;
493 if (ref $from eq 'ARRAY') {
494 return $self->_recurse_from(@$from);
495 } elsif (ref $from eq 'HASH') {
496 return $self->_make_as($from);
497 } else {
498 return $from; # would love to quote here but _table ends up getting called
499 # twice during an ->select without a limit clause due to
500 # the way S::A::Limit->select works. should maybe consider
501 # bypassing this and doing S::A::select($self, ...) in
502 # our select method above. meantime, quoting shims have
503 # been added to select/insert/update/delete here
504 }
505}
506
507sub _recurse_from {
508 my ($self, $from, @join) = @_;
509 my @sqlf;
510 push(@sqlf, $self->_make_as($from));
511 foreach my $j (@join) {
512 my ($to, $on) = @$j;
513
514 # check whether a join type exists
515 my $join_clause = '';
516 my $to_jt = ref($to) eq 'ARRAY' ? $to->[0] : $to;
517 if (ref($to_jt) eq 'HASH' and exists($to_jt->{-join_type})) {
518 $join_clause = ' '.uc($to_jt->{-join_type}).' JOIN ';
519 } else {
520 $join_clause = ' JOIN ';
521 }
522 push(@sqlf, $join_clause);
523
524 if (ref $to eq 'ARRAY') {
525 push(@sqlf, '(', $self->_recurse_from(@$to), ')');
526 } else {
527 push(@sqlf, $self->_make_as($to));
528 }
529 push(@sqlf, ' ON ', $self->_join_condition($on));
530 }
531 return join('', @sqlf);
532}
533
db56cf3d 534sub _fold_sqlbind {
535 my ($self, $sqlbind) = @_;
69989ea9 536
537 my @sqlbind = @$$sqlbind; # copy
538 my $sql = shift @sqlbind;
539 push @{$self->{from_bind}}, @sqlbind;
540
db56cf3d 541 return $sql;
6f4ddea1 542}
543
544sub _make_as {
545 my ($self, $from) = @_;
db56cf3d 546 return join(' ', map { (ref $_ eq 'SCALAR' ? $$_
547 : ref $_ eq 'REF' ? $self->_fold_sqlbind($_)
548 : $self->_quote($_))
6f4ddea1 549 } reverse each %{$self->_skip_options($from)});
550}
551
552sub _skip_options {
553 my ($self, $hash) = @_;
554 my $clean_hash = {};
555 $clean_hash->{$_} = $hash->{$_}
556 for grep {!/^-/} keys %$hash;
557 return $clean_hash;
558}
559
560sub _join_condition {
561 my ($self, $cond) = @_;
562 if (ref $cond eq 'HASH') {
563 my %j;
564 for (keys %$cond) {
565 my $v = $cond->{$_};
566 if (ref $v) {
e8fcf76f 567 croak (ref($v) . qq{ reference arguments are not supported in JOINS - try using \"..." instead'})
6f4ddea1 568 if ref($v) ne 'SCALAR';
569 $j{$_} = $v;
570 }
571 else {
572 my $x = '= '.$self->_quote($v); $j{$_} = \$x;
573 }
574 };
575 return scalar($self->_recurse_where(\%j));
576 } elsif (ref $cond eq 'ARRAY') {
577 return join(' OR ', map { $self->_join_condition($_) } @$cond);
578 } else {
579 die "Can't handle this yet!";
580 }
581}
582
583sub _quote {
584 my ($self, $label) = @_;
585 return '' unless defined $label;
586 return "*" if $label eq '*';
587 return $label unless $self->{quote_char};
588 if(ref $self->{quote_char} eq "ARRAY"){
589 return $self->{quote_char}->[0] . $label . $self->{quote_char}->[1]
590 if !defined $self->{name_sep};
591 my $sep = $self->{name_sep};
592 return join($self->{name_sep},
593 map { $self->{quote_char}->[0] . $_ . $self->{quote_char}->[1] }
594 split(/\Q$sep\E/,$label));
595 }
596 return $self->SUPER::_quote($label);
597}
598
599sub limit_dialect {
600 my $self = shift;
601 $self->{limit_dialect} = shift if @_;
602 return $self->{limit_dialect};
603}
604
998373c2 605# Set to an array-ref to specify separate left and right quotes for table names.
606# A single scalar is equivalen to [ $char, $char ]
6f4ddea1 607sub quote_char {
608 my $self = shift;
609 $self->{quote_char} = shift if @_;
610 return $self->{quote_char};
611}
612
998373c2 613# Character separating quoted table names.
6f4ddea1 614sub name_sep {
615 my $self = shift;
616 $self->{name_sep} = shift if @_;
617 return $self->{name_sep};
618}
619
6201;