From: Peter Rabbitson Date: Thu, 29 Mar 2012 02:53:28 +0000 (+0200) Subject: Refactor a lot of the limit dialects common code - (hopefully) no changes X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=cecf64bc6850edb1c2ad4af03d51aee022326921;p=dbsrgits%2FDBIx-Class-Historic.git Refactor a lot of the limit dialects common code - (hopefully) no changes --- diff --git a/lib/DBIx/Class/SQLMaker/LimitDialects.pm b/lib/DBIx/Class/SQLMaker/LimitDialects.pm index 55a44e6..5af9487 100644 --- a/lib/DBIx/Class/SQLMaker/LimitDialects.pm +++ b/lib/DBIx/Class/SQLMaker/LimitDialects.pm @@ -96,21 +96,20 @@ sub _RowNumberOver { my ($self, $sql, $rs_attrs, $rows, $offset ) = @_; # get selectors, and scan the order_by (if any) - my ($stripped_sql, $in_sel, $out_sel, $alias_map, $extra_order_sel) - = $self->_subqueried_limit_attrs ( $sql, $rs_attrs ); + my $sq_attrs = $self->_subqueried_limit_attrs ( $sql, $rs_attrs ); # make up an order if none exists my $requested_order = (delete $rs_attrs->{order_by}) || $self->_rno_default_order; my $rno_ord = $self->_order_by ($requested_order); # this is the order supplement magic - my $mid_sel = $out_sel; - if ($extra_order_sel) { + my $mid_sel = $sq_attrs->{selection_outer}; + if (my $extra_order_sel = $sq_attrs->{order_supplement}) { for my $extra_col (sort { $extra_order_sel->{$a} cmp $extra_order_sel->{$b} } keys %$extra_order_sel ) { - $in_sel .= sprintf (', %s AS %s', + $sq_attrs->{selection_inner} .= sprintf (', %s AS %s', $extra_col, $extra_order_sel->{$extra_col}, ); @@ -118,7 +117,7 @@ sub _RowNumberOver { } # and this is order re-alias magic - for ($extra_order_sel, $alias_map) { + for ($sq_attrs->{order_supplement}, $sq_attrs->{outer_renames}) { for my $col (keys %$_) { my $re_col = quotemeta ($col); $rno_ord =~ s/$re_col/$_->{$col}/; @@ -135,9 +134,9 @@ sub _RowNumberOver { return <{selection_outer} FROM ( SELECT $mid_sel, ROW_NUMBER() OVER( $rno_ord ) AS $idx_name FROM ( - SELECT $in_sel ${stripped_sql}${group_having} + SELECT $sq_attrs->{selection_inner} $sq_attrs->{query_leftover}${group_having} ) $qalias ) $qalias WHERE $idx_name >= ? AND $idx_name <= ? @@ -243,7 +242,7 @@ Supported by B. sub _RowNum { my ( $self, $sql, $rs_attrs, $rows, $offset ) = @_; - my ($stripped_sql, $insel, $outsel) = $self->_subqueried_limit_attrs ($sql, $rs_attrs); + my $sq_attrs = $self->_subqueried_limit_attrs ($sql, $rs_attrs); my $qalias = $self->_quote ($rs_attrs->{alias}); my $idx_name = $self->_quote ('rownum__index'); @@ -255,8 +254,8 @@ sub _RowNum { push @{$self->{limit_bind}}, [ $self->__rows_bindtype => $rows ]; return <{selection_outer} FROM ( + SELECT $sq_attrs->{selection_inner} $sq_attrs->{query_leftover}${order_group_having} ) $qalias WHERE ROWNUM <= ? EOS } @@ -282,9 +281,9 @@ EOS push @{$self->{limit_bind}}, [ $self->__total_bindtype => $offset + $rows ], [ $self->__offset_bindtype => $offset + 1 ]; return <{selection_outer} FROM ( + SELECT $sq_attrs->{selection_outer}, ROWNUM $idx_name FROM ( + SELECT $sq_attrs->{selection_inner} $sq_attrs->{query_leftover}${order_group_having} ) $qalias WHERE ROWNUM <= ? ) $qalias WHERE $idx_name >= ? EOS @@ -293,9 +292,9 @@ EOS push @{$self->{limit_bind}}, [ $self->__offset_bindtype => $offset + 1 ], [ $self->__total_bindtype => $offset + $rows ]; return <{selection_outer} FROM ( + SELECT $sq_attrs->{selection_outer}, ROWNUM $idx_name FROM ( + SELECT $sq_attrs->{selection_inner} $sq_attrs->{query_leftover}${order_group_having} ) $qalias ) $qalias WHERE $idx_name BETWEEN ? AND ? EOS @@ -307,16 +306,15 @@ sub _prep_for_skimming_limit { my ( $self, $sql, $rs_attrs ) = @_; # get selectors - my (%r, $alias_map, $extra_order_sel); - ($r{inner_sql}, $r{in_sel}, $r{out_sel}, $alias_map, $extra_order_sel) - = $self->_subqueried_limit_attrs ($sql, $rs_attrs); + my $sq_attrs = $self->_subqueried_limit_attrs ($sql, $rs_attrs); my $requested_order = delete $rs_attrs->{order_by}; - $r{order_by_requested} = $self->_order_by ($requested_order); + $sq_attrs->{order_by_requested} = $self->_order_by ($requested_order); + $sq_attrs->{grpby_having} = $self->_parse_rs_attrs ($rs_attrs); # make up an order unless supplied or sanity check what we are given my $inner_order; - if ($r{order_by_requested}) { + if ($sq_attrs->{order_by_requested}) { $self->throw_exception ( 'Unable to safely perform "skimming type" limit with supplied unstable order criteria' ) unless $rs_attrs->{_rsroot_rsrc}->schema->storage->_order_by_is_stable( @@ -340,70 +338,65 @@ sub _prep_for_skimming_limit { } # localise as we already have all the bind values we need - { - local $self->{order_bind}; - $r{order_by_inner} = $self->_order_by ($inner_order); + local $self->{order_bind}; - my @out_chunks; - for my $ch ($self->_order_by_chunks ($inner_order)) { - $ch = $ch->[0] if ref $ch eq 'ARRAY'; + $sq_attrs->{order_by_inner} = $self->_order_by ($inner_order); - $ch =~ s/\s+ ( ASC|DESC ) \s* $//ix; - my $dir = uc ($1||'ASC'); + my @out_chunks; + for my $ch ($self->_order_by_chunks ($inner_order)) { + $ch = $ch->[0] if ref $ch eq 'ARRAY'; - push @out_chunks, \join (' ', $ch, $dir eq 'ASC' ? 'DESC' : 'ASC' ); - } + $ch =~ s/\s+ ( ASC|DESC ) \s* $//ix; + my $dir = uc ($1||'ASC'); - $r{order_by_reversed} = $self->_order_by (\@out_chunks); + push @out_chunks, \join (' ', $ch, $dir eq 'ASC' ? 'DESC' : 'ASC' ); } + $sq_attrs->{quoted_rs_alias} = $self->_quote ($rs_attrs->{alias}); + $sq_attrs->{order_by_middle} = $self->_order_by (\@out_chunks); + $sq_attrs->{selection_middle} = $sq_attrs->{selection_outer}; + # this is the order supplement magic - $r{mid_sel} = $r{out_sel}; - if ($extra_order_sel) { + if (my $extra_order_sel = $sq_attrs->{order_supplement}) { for my $extra_col (sort { $extra_order_sel->{$a} cmp $extra_order_sel->{$b} } keys %$extra_order_sel ) { - $r{in_sel} .= sprintf (', %s AS %s', + $sq_attrs->{selection_inner} .= sprintf (', %s AS %s', $extra_col, $extra_order_sel->{$extra_col}, ); - $r{mid_sel} .= ', ' . $extra_order_sel->{$extra_col}; + $sq_attrs->{selection_middle} .= ', ' . $extra_order_sel->{$extra_col}; } # Whatever order bindvals there are, they will be realiased and - # need to show up in front of the entire initial inner subquery - push @{$self->{pre_select_bind}}, @{$self->{order_bind}}; - } - - # if this is a part of something bigger, we need to add back all - # the extra order_by's, as they may be relied upon by the outside - # of a prefetch or something - if ($rs_attrs->{_is_internal_subuery} and keys %$extra_order_sel) { - $r{out_sel} .= sprintf ", $extra_order_sel->{$_} AS $_" - for sort - { $extra_order_sel->{$a} cmp $extra_order_sel->{$b} } - grep { $_ !~ /[^\w\-]/ } # ignore functions - keys %$extra_order_sel - ; + # reselected, and need to show up at end of the initial inner select + push @{$self->{select_bind}}, @{$self->{order_bind}}; + + # if this is a part of something bigger, we need to add back all + # the extra order_by's, as they may be relied upon by the outside + # of a prefetch or something + if ($rs_attrs->{_is_internal_subuery}) { + $sq_attrs->{selection_outer} .= sprintf ", $extra_order_sel->{$_} AS $_" + for sort + { $extra_order_sel->{$a} cmp $extra_order_sel->{$b} } + grep { $_ !~ /[^\w\-]/ } # ignore functions + keys %$extra_order_sel + ; + } } # and this is order re-alias magic - for my $map ($extra_order_sel, $alias_map) { - for my $col (keys %$map) { + for my $map ($sq_attrs->{order_supplement}, $sq_attrs->{outer_renames}) { + for my $col (sort { $map->{$a} cmp $map->{$b} } keys %{$map||{}}) { my $re_col = quotemeta ($col); $_ =~ s/$re_col/$map->{$col}/ - for ($r{order_by_reversed}, $r{order_by_requested}); + for ($sq_attrs->{order_by_middle}, $sq_attrs->{order_by_requested}); } } - # generate the rest of the sql - $r{grpby_having} = $self->_parse_rs_attrs ($rs_attrs); - - $r{quoted_rs_alias} = $self->_quote ($rs_attrs->{alias}); - - \%r; + $sq_attrs; } =head2 Top @@ -428,31 +421,33 @@ when $limit+$offset > total amount of rows in the resultset. sub _Top { my ( $self, $sql, $rs_attrs, $rows, $offset ) = @_; - my %l = %{ $self->_prep_for_skimming_limit($sql, $rs_attrs) }; + my $lim = $self->_prep_for_skimming_limit($sql, $rs_attrs); $sql = sprintf ('SELECT TOP %u %s %s %s %s', $rows + ($offset||0), - $l{in_sel}, - $l{inner_sql}, - $l{grpby_having}, - $l{order_by_inner}, + $lim->{selection_inner}, + $lim->{query_leftover}, + $lim->{grpby_having}, + $lim->{order_by_inner}, ); $sql = sprintf ('SELECT TOP %u %s FROM ( %s ) %s %s', $rows, - $l{mid_sel}, + $lim->{selection_middle}, $sql, - $l{quoted_rs_alias}, - $l{order_by_reversed}, + $lim->{quoted_rs_alias}, + $lim->{order_by_middle}, ) if $offset; $sql = sprintf ('SELECT TOP %u %s FROM ( %s ) %s %s', $rows, - $l{out_sel}, + $lim->{selection_outer}, $sql, - $l{quoted_rs_alias}, - $l{order_by_requested}, - ) if ( ($offset && $l{order_by_requested}) || ($l{mid_sel} ne $l{out_sel}) ); + $lim->{quoted_rs_alias}, + $lim->{order_by_requested}, + ) if $offset and ( + $lim->{order_by_requested} or $lim->{selection_middle} ne $lim->{selection_outer} + ); return $sql; } @@ -482,31 +477,34 @@ when $limit+$offset > total amount of rows in the resultset. sub _FetchFirst { my ( $self, $sql, $rs_attrs, $rows, $offset ) = @_; - my %l = %{ $self->_prep_for_skimming_limit($sql, $rs_attrs) }; + my $lim = $self->_prep_for_skimming_limit($sql, $rs_attrs); $sql = sprintf ('SELECT %s %s %s %s FETCH FIRST %u ROWS ONLY', - $l{in_sel}, - $l{inner_sql}, - $l{grpby_having}, - $l{order_by_inner}, + $lim->{selection_inner}, + $lim->{query_leftover}, + $lim->{grpby_having}, + $lim->{order_by_inner}, $rows + ($offset||0), ); $sql = sprintf ('SELECT %s FROM ( %s ) %s %s FETCH FIRST %u ROWS ONLY', - $l{mid_sel}, + $lim->{selection_middle}, $sql, - $l{quoted_rs_alias}, - $l{order_by_reversed}, + $lim->{quoted_rs_alias}, + $lim->{order_by_middle}, $rows, ) if $offset; + $sql = sprintf ('SELECT %s FROM ( %s ) %s %s FETCH FIRST %u ROWS ONLY', - $l{out_sel}, + $lim->{selection_outer}, $sql, - $l{quoted_rs_alias}, - $l{order_by_requested}, + $lim->{quoted_rs_alias}, + $lim->{order_by_requested}, $rows, - ) if ( ($offset && $l{order_by_requested}) || ($l{mid_sel} ne $l{out_sel}) ); + ) if $offset and ( + $lim->{order_by_requested} or $lim->{selection_middle} ne $lim->{selection_outer} + ); return $sql; } @@ -586,8 +584,7 @@ sub _GenericSubQ { "Generic Subquery Limit first order criteria '$first_ord_col' must be unique" ) unless $root_rsrc->_identifying_column_set([$first_ord_col]); - my ($stripped_sql, $in_sel, $out_sel, $alias_map, $extra_order_sel) - = $self->_subqueried_limit_attrs ($sql, $rs_attrs); + my $sq_attrs = $self->_subqueried_limit_attrs ($sql, $rs_attrs); my $cmp_op = $direction eq 'desc' ? '>' : '<'; my $count_tbl_alias = 'rownum__emulation'; @@ -595,8 +592,10 @@ sub _GenericSubQ { my $order_sql = $self->_order_by (delete $rs_attrs->{order_by}); my $group_having_sql = $self->_parse_rs_attrs($rs_attrs); + my $in_sel = $sq_attrs->{selection_inner}; + # add the order supplement (if any) as this is what will be used for the outer WHERE - $in_sel .= ", $_" for keys %{$extra_order_sel||{}}; + $in_sel .= ", $_" for keys %{$sq_attrs->{order_supplement}}; my $rownum_cond; if ($offset) { @@ -616,9 +615,9 @@ sub _GenericSubQ { } return sprintf (" -SELECT $out_sel +SELECT $sq_attrs->{selection_outer} FROM ( - SELECT $in_sel ${stripped_sql}${group_having_sql} + SELECT $in_sel $sq_attrs->{query_leftover}${group_having_sql} ) %s WHERE ( SELECT COUNT(*) FROM %s %s WHERE %s $cmp_op %s ) $rownum_cond $order_sql @@ -710,7 +709,7 @@ sub _subqueried_limit_attrs { # unless we are dealing with the current source alias # (which will transcend the subqueries as it is necessary # for possible further chaining) - my (@in_sel, @out_sel, %renamed); + my ($sel, $renamed); for my $node (@sel) { if ( $node->{as} =~ / (?{as} = $self->_unqualify_colname($node->{as}); my $quoted_as = $self->_quote($node->{as}); - push @in_sel, sprintf '%s AS %s', $node->{sql}, $quoted_as; - push @out_sel, $quoted_as; - $renamed{$node->{sql}} = $quoted_as; + push @{$sel->{inner}}, sprintf '%s AS %s', $node->{sql}, $quoted_as; + push @{$sel->{outer}}, $quoted_as; + $renamed->{$node->{sql}} = $quoted_as; } else { - push @in_sel, $node->{sql}; - push @out_sel, $self->_quote ($node->{as}); + push @{$sel->{inner}}, $node->{sql}; + push @{$sel->{outer}}, $self->_quote ($node->{as}); } } + # see if the order gives us anything - my %extra_order_sel; + my $extra_order_sel; for my $chunk ($self->_order_by_chunks ($rs_attrs->{order_by})) { # order with bind $chunk = $chunk->[0] if (ref $chunk) eq 'ARRAY'; @@ -737,20 +737,17 @@ sub _subqueried_limit_attrs { next if $in_sel_index->{$chunk}; - $extra_order_sel{$chunk} ||= $self->_quote ( - 'ORDER__BY__' . scalar keys %extra_order_sel + $extra_order_sel->{$chunk} ||= $self->_quote ( + 'ORDER__BY__' . scalar keys %{$extra_order_sel||{}} ); } - return ( - $proto_sql, - (map { join (', ', @$_ ) } ( - \@in_sel, - \@out_sel) - ), - \%renamed, - keys %extra_order_sel ? \%extra_order_sel : (), - ); + return { + query_leftover => $proto_sql, + (map {( "selection_$_" => join (', ', @{$sel->{$_}} ) )} keys %$sel ), + outer_renames => $renamed, + order_supplement => $extra_order_sel, + }; } sub _unqualify_colname {