From: Peter Rabbitson Date: Sat, 9 Mar 2013 10:57:39 +0000 (+0100) Subject: Consider unselected order_by during complex subqueried prefetch X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=97e130fa48aca5a1255b7014b4cbcb0c30c95328;p=dbsrgits%2FDBIx-Class-Historic.git Consider unselected order_by during complex subqueried prefetch Augment _resolve_aliastypes_from_select_args to collect the column names it sees, allowing it to replace _extract_condition_columns() entirely. In the process fix a number of *incorrect* limit_dialect tests --- diff --git a/Changes b/Changes index 99bd20d..995dc25 100644 --- a/Changes +++ b/Changes @@ -11,6 +11,10 @@ Revision history for DBIx::Class - Warn in case of iterative collapse being upgraded to an eager cursor slurp + * Fixes + - Properly consider unselected order_by criteria during complex + subqueried prefetch + 0.08209 2013-03-01 12:56 (UTC) * New Features / Changes - Debugging aid - warn on invalid result objects created by what diff --git a/lib/DBIx/Class/SQLMaker.pm b/lib/DBIx/Class/SQLMaker.pm index 1162280..c0a464c 100644 --- a/lib/DBIx/Class/SQLMaker.pm +++ b/lib/DBIx/Class/SQLMaker.pm @@ -351,7 +351,6 @@ sub _generate_join_clause { sub _recurse_from { my $self = shift; - return join (' ', $self->_gen_from_blocks(@_) ); } diff --git a/lib/DBIx/Class/Storage/DBIHacks.pm b/lib/DBIx/Class/Storage/DBIHacks.pm index eaa41c4..e5a0d83 100644 --- a/lib/DBIx/Class/Storage/DBIHacks.pm +++ b/lib/DBIx/Class/Storage/DBIHacks.pm @@ -24,7 +24,7 @@ use namespace::clean; # sub _prune_unused_joins { my $self = shift; - my ($from, $select, $where, $attrs) = @_; + my ($from, $select, $where, $attrs, $ignore_multiplication) = @_; return $from unless $self->_use_join_optimizer; @@ -34,20 +34,26 @@ sub _prune_unused_joins { my $aliastypes = $self->_resolve_aliastypes_from_select_args(@_); + # don't care + delete $aliastypes->{joining}; + # a grouped set will not be affected by amount of rows. Thus any # {multiplying} joins can go - delete $aliastypes->{multiplying} if $attrs->{group_by}; + delete $aliastypes->{multiplying} + if $ignore_multiplication or $attrs->{group_by}; my @newfrom = $from->[0]; # FROM head is always present my %need_joins; + for (values %$aliastypes) { # add all requested aliases $need_joins{$_} = 1 for keys %$_; # add all their parents (as per joinpath which is an AoH { table => alias }) - $need_joins{$_} = 1 for map { values %$_ } map { @$_ } values %$_; + $need_joins{$_} = 1 for map { values %$_ } map { @{$_->{-parents}} } values %$_; } + for my $j (@{$from}[1..$#$from]) { push @newfrom, $j if ( (! $j->[0]{-alias}) # legacy crap @@ -86,9 +92,9 @@ sub _adjust_select_args_for_complex_prefetch { # for inside we consider only stuff *not* brought in by the prefetch # on the outside we substitute any function for its alias my $outer_select = [ @$select ]; - my $inner_select = []; + my $inner_select; - my ($root_source, $root_source_offset); + my ($root_node, $root_node_offset); for my $i (0 .. $#$from) { my $node = $from->[$i]; @@ -97,14 +103,15 @@ sub _adjust_select_args_for_complex_prefetch { : next ; - if ( ($h->{-alias}||'') eq $attrs->{alias} and $root_source = $h->{-rsrc} ) { - $root_source_offset = $i; + if ( ($h->{-alias}||'') eq $attrs->{alias} and $h->{-rsrc} ) { + $root_node = $h; + $root_node_offset = $i; last; } } $self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute') - unless $root_source; + unless $root_node; # use the heavy duty resolver to take care of aliased/nonaliased naming my $colinfo = $self->_resolve_column_info($from); @@ -127,48 +134,42 @@ sub _adjust_select_args_for_complex_prefetch { push @{$inner_attrs->{as}}, $attrs->{as}[$i]; } - # We will need to fetch all native columns in the inner subquery, which may be a part - # of an *outer* join condition. We can not just fetch everything because a potential - # has_many restricting join collapse *will not work* on heavy data types. - # Time for more horrible SQL parsing, aughhhh - - # MASSIVE FIXME - in fact when we are fully transitioned to DQ and the support is - # is sane - we will need to trim the select list to *only* fetch stuff that is - # necessary to build joins. In the current implementation if I am selecting a blob - # and the group_by kicks in - we are fucked, and all the user can do is not select - # that column. This is silly! - - my $retardo_sqla_cache = {}; - for my $cond ( map { $_->[1] } @{$from}[$root_source_offset + 1 .. $#$from] ) { - for my $col (@{$self->_extract_condition_columns($cond, $retardo_sqla_cache)}) { - my $ci = $colinfo->{$col}; - if ( - $ci - and - $ci->{-source_alias} eq $attrs->{alias} - and - ! $selected_root_columns->{$ci->{-colname}}++ - ) { - # adding it to both to keep limits not supporting dark selectors happy - push @$inner_select, $ci->{-fq_colname}; - push @{$inner_attrs->{as}}, $ci->{-fq_colname}; - } + # We will need to fetch all native columns in the inner subquery, which may + # be a part of an *outer* join condition, or an order_by (which needs to be + # preserved outside) + # We can not just fetch everything because a potential has_many restricting + # join collapse *will not work* on heavy data types. + my $connecting_aliastypes = $self->_resolve_aliastypes_from_select_args( + [grep { ref($_) eq 'ARRAY' or ref($_) eq 'HASH' } @{$from}[$root_node_offset .. $#$from]], + [], + $where, + $inner_attrs + ); + + for (sort map { keys %{$_->{-seen_columns}||{}} } map { values %$_ } values %$connecting_aliastypes) { + my $ci = $colinfo->{$_} or next; + if ( + $ci->{-source_alias} eq $attrs->{alias} + and + ! $selected_root_columns->{$ci->{-colname}}++ + ) { + # adding it to both to keep limits not supporting dark selectors happy + push @$inner_select, $ci->{-fq_colname}; + push @{$inner_attrs->{as}}, $ci->{-fq_colname}; } } # construct the inner $from and lock it in a subquery # we need to prune first, because this will determine if we need a group_by below - # the fake group_by is so that the pruner throws away all non-selecting, non-restricting - # multijoins (since we def. do not care about those inside the subquery) - + # throw away all non-selecting, non-restricting multijoins + # (since we def. do not care about multiplication those inside the subquery) my $inner_subq = do { # must use it here regardless of user requests local $self->{_use_join_optimizer} = 1; - my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, { - group_by => ['dummy'], %$inner_attrs, - }); + # throw away multijoins since we def. do not care about those inside the subquery + my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, $inner_attrs, 'ignore_multiplication'); my $inner_aliastypes = $self->_resolve_aliastypes_from_select_args( $inner_from, $inner_select, $where, $inner_attrs ); @@ -197,7 +198,8 @@ sub _adjust_select_args_for_complex_prefetch { } # we already optimized $inner_from above - local $self->{_use_join_optimizer} = 0; + # and already local()ized + $self->{_use_join_optimizer} = 0; # generate the subquery $self->_select_args_to_query ( @@ -224,24 +226,20 @@ sub _adjust_select_args_for_complex_prefetch { my @outer_from; # we may not be the head - if ($root_source_offset) { + if ($root_node_offset) { # first generate the outer_from, up to the substitution point - @outer_from = splice @$from, 0, $root_source_offset; - - my $root_node = shift @$from; + @outer_from = splice @$from, 0, $root_node_offset; push @outer_from, [ { -alias => $attrs->{alias}, - -rsrc => $root_node->[0]{-rsrc}, + -rsrc => $root_node->{-rsrc}, $attrs->{alias} => $inner_subq, }, - @{$root_node}[1 .. $#$root_node], + @{$from->[0]}[1 .. $#{$from->[0]}], ]; } else { - my $root_node = shift @$from; - @outer_from = { -alias => $attrs->{alias}, -rsrc => $root_node->{-rsrc}, @@ -249,6 +247,8 @@ sub _adjust_select_args_for_complex_prefetch { }; } + shift @$from; # it's replaced in @outer_from already + # scan the *remaining* from spec against different attributes, and see which joins are needed # in what role my $outer_aliastypes = @@ -256,7 +256,7 @@ sub _adjust_select_args_for_complex_prefetch { # unroll parents my ($outer_select_chain, $outer_restrict_chain) = map { +{ - map { $_ => 1 } map { values %$_} map { @$_ } values %{ $outer_aliastypes->{$_} || {} } + map { $_ => 1 } map { values %$_} map { @{$_->{-parents}} } values %{ $outer_aliastypes->{$_} } } } qw/selecting restricting/; # see what's left - throw away if not selecting/restricting @@ -331,7 +331,7 @@ sub _resolve_aliastypes_from_select_args { or next; $alias_list->{$al} = $j; - $aliases_by_type->{multiplying}{$al} ||= $j->{-join_path}||[] if ( + $aliases_by_type->{multiplying}{$al} ||= { -parents => $j->{-join_path}||[] } if ( # not array == {from} head == can't be multiplying ( ref($_) eq 'ARRAY' and ! $j->{-is_single} ) or @@ -351,6 +351,7 @@ sub _resolve_aliastypes_from_select_args { local $sql_maker->{where_bind}; local $sql_maker->{group_bind}; local $sql_maker->{having_bind}; + local $sql_maker->{from_bind}; # we can't scan properly without any quoting (\b doesn't cut it # everywhere), so unless there is proper quoting set - use our @@ -378,6 +379,12 @@ sub _resolve_aliastypes_from_select_args { map { $_ => $attrs->{$_} } (qw/group_by having/) }), ], + joining => [ + $sql_maker->_recurse_from ( + ref $from->[0] eq 'ARRAY' ? $from->[0][0] : $from->[0], + @{$from}[1 .. $#$from], + ), + ], selecting => [ $sql_maker->_recurse_fields ($select), ( map { $_->[0] } $self->_extract_order_criteria ($attrs->{order_by}, $sql_maker) ), @@ -391,15 +398,18 @@ sub _resolve_aliastypes_from_select_args { # alias (should work even if they are in scalarrefs) for my $alias (keys %$alias_list) { my $al_re = qr/ - $lquote $alias $rquote $sep + $lquote $alias $rquote $sep (?: $lquote ([^$rquote]+) $rquote )? | - \b $alias \. + \b $alias \. ([^\s\)\($rquote]+)? /x; for my $type (keys %$to_scan) { for my $piece (@{$to_scan->{$type}}) { - $aliases_by_type->{$type}{$alias} ||= $alias_list->{$alias}{-join_path}||[] - if ($piece =~ $al_re); + if (my @matches = $piece =~ /$al_re/g) { + $aliases_by_type->{$type}{$alias} ||= { -parents => $alias_list->{$alias}{-join_path}||[] }; + $aliases_by_type->{$type}{$alias}{-seen_columns}{"$alias.$_"} = 1 + for grep { defined $_ } @matches; + } } } } @@ -409,13 +419,15 @@ sub _resolve_aliastypes_from_select_args { for my $col (keys %$colinfo) { next if $col =~ / \. /x; # if column is qualified it was caught by the above - my $col_re = qr/ $lquote $col $rquote /x; + my $col_re = qr/ $lquote ($col) $rquote /x; for my $type (keys %$to_scan) { for my $piece (@{$to_scan->{$type}}) { - if ($piece =~ $col_re) { + if (my @matches = $piece =~ /$col_re/g) { my $alias = $colinfo->{$col}{-source_alias}; - $aliases_by_type->{$type}{$alias} ||= $alias_list->{$alias}{-join_path}||[]; + $aliases_by_type->{$type}{$alias} ||= { -parents => $alias_list->{$alias}{-join_path}||[] }; + $aliases_by_type->{$type}{$alias}{-seen_columns}{"$alias.$_"} = 1 + for grep { defined $_ } @matches; } } } @@ -424,7 +436,7 @@ sub _resolve_aliastypes_from_select_args { # Add any non-left joins to the restriction list (such joins are indeed restrictions) for my $j (values %$alias_list) { my $alias = $j->{-alias} or next; - $aliases_by_type->{restricting}{$alias} ||= $j->{-join_path}||[] if ( + $aliases_by_type->{restricting}{$alias} ||= { -parents => $j->{-join_path}||[] } if ( (not $j->{-join_type}) or ($j->{-join_type} !~ /^left (?: \s+ outer)? $/xi) @@ -646,61 +658,6 @@ sub _inner_join_to_node { return \@new_from; } -# yet another atrocity: attempt to extract all columns from a -# where condition by hooking _quote -sub _extract_condition_columns { - my ($self, $cond, $sql_maker_cache) = @_; - - return [] unless $cond; - - my $sm = $sql_maker_cache->{condparser} ||= $self->{_sql_ident_capturer} ||= do { - # FIXME - replace with a Moo trait - my $orig_sm_class = ref $self->sql_maker; - my $smic_class = "${orig_sm_class}::_IdentCapture_"; - - unless ($smic_class->isa('SQL::Abstract')) { - - no strict 'refs'; - *{"${smic_class}::_quote"} = subname "${smic_class}::_quote" => sub { - my ($self, $ident) = @_; - if (ref $ident eq 'SCALAR') { - $ident = $$ident; - my $storage_quotes = $self->sql_quote_char || '"'; - my ($ql, $qr) = map - { quotemeta $_ } - (ref $storage_quotes eq 'ARRAY' ? @$storage_quotes : ($storage_quotes) x 2 ) - ; - - while ($ident =~ / - $ql (\w+) $qr - | - ([\w\.]+) - /xg) { - $self->{_captured_idents}{$1||$2}++; - } - } - else { - $self->{_captured_idents}{$ident}++; - } - return $ident; - }; - - *{"${smic_class}::_get_captured_idents"} = subname "${smic_class}::_get_captures" => sub { - (delete shift->{_captured_idents}) || {}; - }; - - $self->inject_base ($smic_class, $orig_sm_class); - - } - - $smic_class->new(); - }; - - $sm->_recurse_where($cond); - - return [ sort keys %{$sm->_get_captured_idents} ]; -} - sub _extract_order_criteria { my ($self, $order_by, $sql_maker) = @_; diff --git a/t/prefetch/incomplete.t b/t/prefetch/incomplete.t index 8840c1d..a710fbb 100644 --- a/t/prefetch/incomplete.t +++ b/t/prefetch/incomplete.t @@ -6,6 +6,7 @@ use Test::Deep; use Test::Exception; use lib qw(t/lib); use DBICTest; +use DBIC::SqlMakerTest; my $schema = DBICTest->init_schema(); @@ -119,9 +120,105 @@ throws_ok( prefetch => 'books', }); - lives_ok { - is ($pref_rs->all, 1, 'Expected count of objects on limtied prefetch') - } "Complex limited prefetch works with non-selected join condition"; + is_same_sql_bind( + $pref_rs->as_query, + '( + SELECT me.name, books.id, books.source, books.owner, books.title, books.price + FROM ( + SELECT me.name, me.id + FROM owners me + LIMIT ? + OFFSET ? + ) me + LEFT JOIN books books + ON books.owner = me.id + )', + [ [ { sqlt_datatype => "integer" } => 3 ], [ { sqlt_datatype => "integer" } => 1 ] ], + 'Expected SQL on complex limited prefetch with non-selected join condition', + ); + + is_deeply ( + $pref_rs->all_hri, + [ { + name => "Waltham", + books => [ { + id => 3, + owner => 2, + price => 65, + source => "Library", + title => "Best Recipe Cookbook", + } ], + } ], + 'Expected result on complex limited prefetch with non-selected join condition' + ); + + my $empty_ordered_pref_rs = $pref_rs->search({}, { + columns => [], # nothing, we only prefetch the book data + order_by => 'me.name', + }); + my $empty_ordered_pref_hri = [ { + books => [ { + id => 3, + owner => 2, + price => 65, + source => "Library", + title => "Best Recipe Cookbook", + } ], + } ]; + + is_same_sql_bind( + $empty_ordered_pref_rs->as_query, + '( + SELECT books.id, books.source, books.owner, books.title, books.price + FROM ( + SELECT me.id, me.name + FROM owners me + ORDER BY me.name + LIMIT ? + OFFSET ? + ) me + LEFT JOIN books books + ON books.owner = me.id + ORDER BY me.name + )', + [ [ { sqlt_datatype => "integer" } => 3 ], [ { sqlt_datatype => "integer" } => 1 ] ], + 'Expected SQL on *ordered* complex limited prefetch with non-selected root data', + ); + + is_deeply ( + $empty_ordered_pref_rs->all_hri, + $empty_ordered_pref_hri, + 'Expected result on *ordered* complex limited prefetch with non-selected root data' + ); + + $empty_ordered_pref_rs = $empty_ordered_pref_rs->search({}, { + order_by => [ \ 'LENGTH(me.name)', \ 'RANDOM()' ], + }); + + is_same_sql_bind( + $empty_ordered_pref_rs->as_query, + '( + SELECT books.id, books.source, books.owner, books.title, books.price + FROM ( + SELECT me.id, me.name + FROM owners me + ORDER BY LENGTH(me.name), RANDOM() + LIMIT ? + OFFSET ? + ) me + LEFT JOIN books books + ON books.owner = me.id + ORDER BY LENGTH(me.name), RANDOM() + )', + [ [ { sqlt_datatype => "integer" } => 3 ], [ { sqlt_datatype => "integer" } => 1 ] ], + 'Expected SQL on *function-ordered* complex limited prefetch with non-selected root data', + ); + + is_deeply ( + $empty_ordered_pref_rs->all_hri, + $empty_ordered_pref_hri, + 'Expected result on *function-ordered* complex limited prefetch with non-selected root data' + ); } diff --git a/t/sqlmaker/limit_dialects/fetch_first.t b/t/sqlmaker/limit_dialects/fetch_first.t index 302201c..10d3e60 100644 --- a/t/sqlmaker/limit_dialects/fetch_first.t +++ b/t/sqlmaker/limit_dialects/fetch_first.t @@ -152,11 +152,11 @@ is_same_sql_bind ( $books_45_and_owners->search ({}, { group_by => 'title', order_by => 'title' })->as_query, '(SELECT me.id, me.source, me.owner, me.price, owner.id, owner.name FROM ( - SELECT me.id, me.source, me.owner, me.price + SELECT me.id, me.source, me.owner, me.price, me.title FROM ( - SELECT me.id, me.source, me.owner, me.price, ORDER__BY__001 + SELECT me.id, me.source, me.owner, me.price, me.title FROM ( - SELECT me.id, me.source, me.owner, me.price, title AS ORDER__BY__001 + SELECT me.id, me.source, me.owner, me.price, me.title FROM books me JOIN owners owner ON owner.id = me.owner WHERE ( source = ? ) @@ -164,10 +164,10 @@ is_same_sql_bind ( ORDER BY title FETCH FIRST 5 ROWS ONLY ) me - ORDER BY ORDER__BY__001 DESC + ORDER BY title DESC FETCH FIRST 2 ROWS ONLY ) me - ORDER BY ORDER__BY__001 + ORDER BY title ) me JOIN owners owner ON owner.id = me.owner WHERE ( source = ? ) diff --git a/t/sqlmaker/limit_dialects/toplimit.t b/t/sqlmaker/limit_dialects/toplimit.t index 11f4c08..88c99a6 100644 --- a/t/sqlmaker/limit_dialects/toplimit.t +++ b/t/sqlmaker/limit_dialects/toplimit.t @@ -192,22 +192,22 @@ is_same_sql_bind ( $books_45_and_owners->search ({}, { group_by => 'title', order_by => 'title' })->as_query, '(SELECT me.id, me.source, me.owner, me.price, owner.id, owner.name FROM ( - SELECT me.id, me.source, me.owner, me.price + SELECT me.id, me.source, me.owner, me.price, me.title FROM ( SELECT TOP 2 - me.id, me.source, me.owner, me.price, ORDER__BY__001 + me.id, me.source, me.owner, me.price, me.title FROM ( SELECT TOP 5 - me.id, me.source, me.owner, me.price, title AS ORDER__BY__001 + me.id, me.source, me.owner, me.price, me.title FROM books me JOIN owners owner ON owner.id = me.owner WHERE ( source = ? ) GROUP BY title ORDER BY title ) me - ORDER BY ORDER__BY__001 DESC + ORDER BY title DESC ) me - ORDER BY ORDER__BY__001 + ORDER BY title ) me JOIN owners owner ON owner.id = me.owner WHERE ( source = ? )