-package DBIx::Class::ResultSource::RowParser;
+package # hide from the pauses
+ DBIx::Class::ResultSource::RowParser;
use strict;
use warnings;
map {
$self->_resolve_prefetch($_, $alias, $alias_map, $order, [ @$pref_path ] ),
$self->related_source($_)->_resolve_prefetch(
- $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] )
+ $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] )
} keys %$pre;
return @ret;
}
unless $rel_info;
my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
- my $rel_source = $self->related_source($pre);
-
- if ($rel_info->{attrs}{accessor} && $rel_info->{attrs}{accessor} eq 'multi') {
- $self->throw_exception(
- "Can't prefetch has_many ${pre} (join cond too complex)")
- unless ref($rel_info->{cond}) eq 'HASH';
- my $dots = @{[$as_prefix =~ m/\./g]} + 1; # +1 to match the ".${as_prefix}"
-
- #my @col = map { (/^self\.(.+)$/ ? ("${as_prefix}.$1") : ()); }
- # values %{$rel_info->{cond}};
- my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
- keys %{$rel_info->{cond}};
-
- push @$order, map { "${as}.$_" } @key;
-
- if (my $rel_order = $rel_info->{attrs}{order_by}) {
- # this is kludgy and incomplete, I am well aware
- # but the parent method is going away entirely anyway
- # so sod it
- my $sql_maker = $self->storage->sql_maker;
- my ($orig_ql, $orig_qr) = $sql_maker->_quote_chars;
- my $sep = $sql_maker->name_sep;
-
- # install our own quoter, so we can catch unqualified stuff
- local $sql_maker->{quote_char} = ["\x00", "\xFF"];
-
- my $quoted_prefix = "\x00${as}\xFF";
-
- for my $chunk ( $sql_maker->_order_by_chunks ($rel_order) ) {
- my @bind;
- ($chunk, @bind) = @$chunk if ref $chunk;
-
- $chunk = "${quoted_prefix}${sep}${chunk}"
- unless $chunk =~ /\Q$sep/;
-
- $chunk =~ s/\x00/$orig_ql/g;
- $chunk =~ s/\xFF/$orig_qr/g;
- push @$order, \[$chunk, @bind];
- }
- }
- }
return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
- $rel_source->columns;
+ $self->related_source($pre)->columns;
}
}
-# Takes a selection list and generates a collapse-map representing
+# Takes an arrayref selection list and generates a collapse-map representing
# row-object fold-points. Every relationship is assigned a set of unique,
# non-nullable columns (which may *not even be* from the same resultset)
# and the collapser will use this information to correctly distinguish
-# data of individual to-be-row-objects.
+# data of individual to-be-row-objects. See t/resultset/rowparser_internals.t
+# for extensive RV examples
sub _resolve_collapse {
my ($self, $as, $as_fq_idx, $rel_chain, $parent_info, $node_idx_ref) = @_;
$_ =~ s/^ (?: foreign | self ) \.//x for ($f, $s);
$relinfo->{$rel}{fk_map}{$s} = $f;
- # need to know source from *our* pov, hnce $rel.
+ # need to know source from *our* pov, hence $rel.
$my_cols->{$s} ||= { via_fk => "$rel.$f" } if (
defined $rel_cols->{$rel}{$f} # in fact selected
and
- (! $node_idx_ref or $relinfo->{$rel}{is_inner}) # either top-level or an inner join
+ $relinfo->{$rel}{is_inner}
);
}
}
if (
$my_cols
and
- my $uset = $self->_unique_column_set ($my_cols)
+ my $idset = $self->_identifying_column_set ({map { $_ => $my_cols->{$_}{colinfo} } keys %$my_cols})
) {
# see if the resulting collapser relies on any implied columns,
# and fix stuff up if this is the case
+ my @reduced_set = grep { ! $assumed_from_parent->{columns}{$_} } @$idset;
- my $parent_collapser_used = defined delete @{$uset}{keys %{$assumed_from_parent->{columns}}};
$collapse_map->{-node_id} = __unique_numlist(
- $parent_collapser_used ? @{$parent_info->{collapse_on}} : (),
+ (@reduced_set != @$idset) ? @{$parent_info->{collapse_on}} : (),
(map
{
my $fqc = join ('.',
$as_fq_idx->{$fqc};
}
- keys %$uset
+ @reduced_set
),
);
}
return $collapse_map;
}
-sub _unique_column_set {
- my ($self, $cols) = @_;
-
- my %unique = $self->unique_constraints;
-
- # always prefer the PK first, and then shortest constraints first
- USET:
- for my $set (delete $unique{primary}, sort { @$a <=> @$b } (values %unique) ) {
- next unless $set && @$set;
-
- for (@$set) {
- next USET unless ($cols->{$_} && $cols->{$_}{colinfo} && !$cols->{$_}{colinfo}{is_nullable} );
- }
-
- return { map { $_ => 1 } @$set };
- }
-
- return undef;
-}
-
# Takes an arrayref of {as} dbic column aliases and the collapse and select
-# attributes from the same $rs (the slector requirement is a temporary
-# workaround), and returns a coderef capable of:
-# my $me_pref_clps = $coderef->([$rs->cursor->next])
-# Where the $me_pref_clps arrayref is the future argument to
-# ::ResultSet::_collapse_result.
-#
-# $me_pref_clps->[0] is always returned (even if as an empty hash with no
-# rowdata), however branches of related data in $me_pref_clps->[1] may be
-# pruned short of what was originally requested based on {as}, depending
-# on:
-#
-# * If collapse is requested, a definitive collapse map is calculated for
-# every relationship "fold-point", consisting of a set of values (which
-# may not even be contained in the future 'me' of said relationship
-# (for example a cd.artist_id defines the related inner-joined artist)).
-# Thus a definedness check is carried on all collapse-condition values
-# and if at least one is undef it is assumed that we are dealing with a
-# NULLed right-side of a left-join, so we don't return a related data
-# container at all, which implies no related objects
-#
-# * If we are not collapsing, there is no constraint on having a selector
-# uniquely identifying all possible objects, and the user might have very
-# well requested a column that just *happens* to be all NULLs. What we do
-# in this case is fallback to the old behavior (which is a potential FIXME)
-# by always returning a data container, but only filling it with columns
-# IFF at least one of them is defined. This way we do not get an object
-# with a bunch of has_column_loaded to undef, but at the same time do not
-# further relationships based off this "null" object (e.g. in case the user
-# deliberately skipped link-table values). I am pretty sure there are some
-# tests that codify this behavior, need to find the exact testname.
+# attributes from the same $rs (the selector requirement is a temporary
+# workaround... I hope), and returns a coderef capable of:
+# my $me_pref_clps = $coderef->([$rs->cursor->next/all])
+# Where the $me_pref_clps arrayref is the future argument to inflate_result()
#
# For an example of this coderef in action (and to see its guts) look at
-# t/prefetch/_internals.t
+# t/resultset/rowparser_internals.t
#
-# This is a huge performance win, as we call the same code for
-# every row returned from the db, thus avoiding repeated method
-# lookups when traversing relationships
+# This is a huge performance win, as we call the same code for # every row
+# returned from the db, thus avoiding repeated method lookups when traversing
+# relationships
#
# Also since the coderef is completely stateless (the returned structure is
# always fresh on every new invocation) this is a very good opportunity for
# memoization if further speed improvements are needed
#
-# The way we construct this coderef is somewhat fugly, although I am not
-# sure if the string eval is *that* bad of an idea. The alternative is to
-# have a *very* large number of anon coderefs calling each other in a twisty
-# maze, whereas the current result is a nice, smooth, single-pass function.
+# The way we construct this coderef is somewhat fugly, although the result is
+# really worth it. The final coderef does not perform any kind of recursion -
+# the entire nested structure constructor is rolled out into a single scope.
+#
# In any case - the output of this thing is meticulously micro-tested, so
-# any sort of rewrite should be relatively easy
+# any sort of adjustment/rewrite should be relatively easy (fsvo relatively)
#
sub _mk_row_parser {
my ($self, $args) = @_;
( 0 .. $#{$args->{inflate_map}} )
};
- my ($parser_src);
- if ($args->{collapse}) {
- # FIXME - deal with unorderedness
- # unordered => $unordered
+ my $parser_src;
+
+ # the non-collapsing assembler is easy
+ # FIXME SUBOPTIMAL there could be a yet faster way to do things here, but
+ # need to try an actual implementation and benchmark it:
+ #
+ # <timbunce_> First setup the nested data structure you want for each row
+ # Then call bind_col() to alias the row fields into the right place in
+ # the data structure, then to fetch the data do:
+ # push @rows, dclone($row_data_struct) while ($sth->fetchrow);
+ #
+ if (!$args->{collapse}) {
+ $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple(
+ $inflate_index,
+ { rsrc => $self }, # need the $rsrc to sanity-check inflation map once
+ ));
+
+ # change the quoted placeholders to unquoted alias-references
+ $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex;
+ }
+
+ # the collapsing parser is more complicated - it needs to keep a lot of state
+ #
+ else {
my $collapse_map = $self->_resolve_collapse (
# FIXME
# alias random crap to existing column names anyway, but still - just in
# case
# FIXME !!!! - this does not yet deal with unbalanced selectors correctly
- # (it is now trivial as the attrs specify where things go out of sync)
+ # (it is now trivial as the attrs specify where things go out of sync
+ # needs MOAR tests)
{ map
{ ref $args->{selection}[$inflate_index->{$_}] ? () : ( $_ => $inflate_index->{$_} ) }
keys %$inflate_index
}
);
- my $unrolled_top_branch_id_indexes = join (', ', @{$collapse_map->{-branch_id}});
+ my $top_branch_idx_list = join (', ', @{$collapse_map->{-branch_id}});
- my ($sequenced_top_branch_id, $sequenced_top_node_id) = map
- { join ('', map { "{'\xFF__IDVALPOS__${_}__\xFF'}" } @$_ ) }
- $collapse_map->{-branch_id}, $collapse_map->{-node_id}
- ;
+ my $top_node_id_path = join ('', map
+ { "{'\xFF__IDVALPOS__${_}__\xFF'}" }
+ @{$collapse_map->{-node_id}}
+ );
- my $rolled_out_assemblers = __visit_infmap_collapse (
+ my $rel_assemblers = __visit_infmap_collapse (
$inflate_index, $collapse_map
);
- my @sprintf_args = (
- $unrolled_top_branch_id_indexes,
- $sequenced_top_branch_id,
- $sequenced_top_node_id,
- $rolled_out_assemblers,
- );
-
- $parser_src = sprintf (<<'EOS', @sprintf_args);
+ $parser_src = sprintf (<<'EOS', $top_branch_idx_list, $top_node_id_path, $rel_assemblers);
### BEGIN STRING EVAL
- my ($rows_pos, $result_pos, $cur_row, @cur_row_id_values, $is_new_res, @collapse_idx) = (0,0);
+
+ my ($rows_pos, $result_pos, $cur_row, @cur_row_ids, @collapse_idx, $is_new_res) = (0,0);
# this loop is a bit arcane - the rationale is that the passed in
# $_[0] will either have only one row (->next) or will have all
# array, since the collapsed prefetch is smaller by definition.
# At the end we cut the leftovers away and move on.
while ($cur_row =
- ( ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; 0 } )
+ ( ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
||
($_[1] and $_[1]->())
) {
- # FIXME
- # optimize this away when we know we have no undefs in the collapse map
- $cur_row_id_values[$_] = defined $cur_row->[$_] ? $cur_row->[$_] : "\xFF\xFFN\xFFU\xFFL\xFFL\xFF\xFF"
+ $cur_row_ids[$_] = defined $cur_row->[$_] ? $cur_row->[$_] : "\xFF\xFFN\xFFU\xFFL\xFFL\xFF\xFF"
for (%1$s); # the top branch_id includes all id values
- # check top branch for doubling via a has_many non-selecting join or something
- # 0 is reserved for this (node indexes start from 1)
- next if $collapse_idx[0]%2$s++;
-
- $is_new_res = ! $collapse_idx[1]%3$s;
-
- # lazify
- # fire on ordered only
-# if ($is_new_res = ! $collapse_idx[1]{$cur_row_id_values[2]}) {
-# }
+ $is_new_res = ! $collapse_idx[1]%2$s and (
+ $_[1] and $result_pos and (unshift @{$_[2]}, $cur_row) and last
+ );
- %4$s
+ %3$s
- $_[0][$result_pos++] = $collapse_idx[1]%3$s
+ $_[0][$result_pos++] = $collapse_idx[1]%2$s
if $is_new_res;
}
### END STRING EVAL
EOS
+ # !!! note - different var than the one above
# change the quoted placeholders to unquoted alias-references
$parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$cur_row->[$1]"/gex;
- $parser_src =~ s/ \' \xFF__IDVALPOS__(\d+)__\xFF \' /"\$cur_row_id_values[$1]"/gex;
- }
-
- else {
- $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple(
- $inflate_index, { rsrc => $self }), # need the $rsrc to determine left-ness
- );
-
- # change the quoted placeholders to unquoted alias-references
- # !!! note - different var than the one above
- $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex;
+ $parser_src =~ s/ \' \xFF__IDVALPOS__(\d+)__\xFF \' /"\$cur_row_ids[$1]"/gex;
}
$parser_src;
}
+# the simple non-collapsing nested structure recursor
sub __visit_infmap_simple {
my ($val_idx, $args) = @_;
my @relperl;
for my $rel (sort keys %$rel_cols) {
- my $rel_rsrc = __get_related_source($args->{rsrc}, $rel, $rel_cols->{$rel});
-
+ # DISABLEPRUNE
#my $optional = $args->{is_optional};
#$optional ||= ($args->{rsrc}->relationship_info($rel)->{attrs}{join_type} || '') =~ /^left/i;
push @relperl, join ' => ', perlstring($rel), __visit_infmap_simple($rel_cols->{$rel}, {
- non_top => 1,
+ rsrc => __get_related_source($args->{rsrc}, $rel, $rel_cols->{$rel}),
+ # DISABLEPRUNE
+ #non_top => 1,
#is_optional => $optional,
- rsrc => $rel_rsrc,
});
- # FIXME SUBOPTIMAL - disabled to satisfy t/resultset/inflate_result_api.t
+ # FIXME SUBOPTIMAL DISABLEPRUNE - disabled to satisfy t/resultset/inflate_result_api.t
#if ($optional and my @branch_null_checks = map
# { "(! defined '\xFF__VALPOS__${_}__\xFF')" }
# sort { $a <=> $b } values %{$rel_cols->{$rel}}
);
}
+# the collapsing nested structure recursor
sub __visit_infmap_collapse {
my ($val_idx, $collapse_map, $parent_info) = @_;
my $me_struct = keys %$my_cols
? __visit_dump([{ map { $_ => "\xFF__VALPOS__$my_cols->{$_}__\xFF" } (keys %$my_cols) }])
- : 'undef'
+ : undef
;
my $node_idx_ref = sprintf '$collapse_idx[%d]%s', $collapse_map->{-node_index}, $sequenced_node_id;
push @src, sprintf( '%s ||= %s;',
$node_idx_ref,
$me_struct,
- );
+ ) if $me_struct;
}
elsif ($collapse_map->{-is_single}) {
- push @src, sprintf ( '%s = %s ||= %s;',
+ push @src, sprintf ( '%s ||= %s%s;',
$parent_idx_ref,
$node_idx_ref,
- $me_struct,
+ $me_struct ? " ||= $me_struct" : '',
);
}
else {
- push @src, sprintf('push @{%s}, %s = %s if !%s;',
+ push @src, sprintf('push @{%s}, %s%s unless %s;',
$parent_idx_ref,
$node_idx_ref,
- $me_struct,
+ $me_struct ? " ||= $me_struct" : '',
$node_idx_ref,
);
}
+ # DISABLEPRUNE
#my $known_defined = { %{ $parent_info->{known_defined} || {} } };
#$known_defined->{$_}++ for @{$collapse_map->{-node_id}};
for my $rel (sort keys %$rel_cols) {
- push @src, sprintf( '%s[1]{%s} ||= [];', $node_idx_ref, perlstring($rel) );
+ push @src, sprintf( '%s[1]{%s} ||= [];', $node_idx_ref, perlstring($rel) )
+ unless $collapse_map->{$rel}{-is_single};
push @src, __visit_infmap_collapse($rel_cols->{$rel}, $collapse_map->{$rel}, {
node_idx => $collapse_map->{-node_index},
sequenced_node_id => $sequenced_node_id,
relname => $rel,
+ # DISABLEPRUNE
#known_defined => $known_defined,
});
- # FIXME SUBOPTIMAL - disabled to satisfy t/resultset/inflate_result_api.t
+ # FIXME SUBOPTIMAL DISABLEPRUNE - disabled to satisfy t/resultset/inflate_result_api.t
#if ($collapse_map->{$rel}{-is_optional} and my @null_checks = map
- # { "(! defined '\xFF__VALPOS__${_}__\xFF')" }
+ # { "(! defined '\xFF__IDVALPOS__${_}__\xFF')" }
# sort { $a <=> $b } grep
# { ! $known_defined->{$_} }
# @{$collapse_map->{$rel}{-node_id}}
($dumper_obj ||= do {
require Data::Dumper;
Data::Dumper->new([])
- ->Useperl (1)
+ ->Useperl (0)
->Purity (1)
->Pad ('')
->Useqq (0)