# Run the query, passing the result_class since it should propagate for find
my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
- if (keys %{$rs->_resolved_attrs->{collapse}}) {
+ if ($rs->_resolved_attrs->{collapse}) {
my $row = $rs->next;
carp "Query returned more than one row" if $rs->next;
return $row;
my $attrs = $self->_resolved_attrs_copy;
- if (keys %{$attrs->{collapse}}) {
+ if ($attrs->{collapse}) {
$self->throw_exception(
'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
);
$attrs->{where}, $attrs
);
- return (@data ? ($self->_construct_object(@data))[0] : undef);
+ return @data
+ ? ($self->_construct_objects(@data))[0]
+ : undef
+ ;
}
: $self->cursor->next
);
return undef unless (@row);
- my ($row, @more) = $self->_construct_object(@row);
+ my ($row, @more) = $self->_construct_objects(@row);
$self->{stashed_objects} = \@more if @more;
return $row;
}
-sub _construct_object {
+# takes a single DBI-row of data and coinstructs as many objects
+# as the resultset attributes call for.
+# This can be a bit of an action at a distance - it takes as an argument
+# the *current* cursor-row (already taken off the $sth), but if
+# collapsing is requested it will keep advancing the cursor either
+# until the current row-object is assembled (the collapser was able to
+# order the result sensibly) OR until the cursor is exhausted (an
+# unordered collapsing resultset effectively triggers ->all)
+
+# FIXME: why the *FUCK* do we pass around DBI data by copy?! Sadly needs
+# assessment before changing...
+#
+sub _construct_objects {
my ($self, @row) = @_;
+ my $attrs = $self->_resolved_attrs;
+ my $keep_collapsing = $attrs->{collapse};
+
+ my $res_index;
+=begin
+ do {
+ my $me_pref_col = $attrs->{_row_parser}->($row_ref);
+
+ my $container;
+ if ($keep_collapsing) {
+
+ # FIXME - we should be able to remove these 2 checks after the design validates
+ $self->throw_exception ('Collapsing without a top-level collapse-set... can not happen')
+ unless @{$me_ref_col->[2]};
+ $self->throw_exception ('Top-level collapse-set contains a NULL-value... can not happen')
+ if grep { ! defined $_ } @{$me_pref_col->[2]};
+
+ my $main_ident = join "\x00", @{$me_pref_col->[2]};
+
+ if (! $res_index->{$main_ident}) {
+ # this is where we bail out IFF we are ordered, and the $main_ident changes
+
+ $res_index->{$main_ident} = {
+ all_me_pref => [,
+ index => scalar keys %$res_index,
+ };
+ }
+ }
+
+
- my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
+ $container = $res_index->{$main_ident}{container};
+ };
+
+ push @$container, [ @{$me_pref_col}[0,1] ];
+
+
+
+ } while (
+ $keep_collapsing
+ &&
+ do { $row_ref = [$self->cursor->next]; $self->{stashed_row} = $row_ref if @$row_ref; scalar @$row_ref }
+ );
+
+ # attempt collapse all rows with same collapse identity
+ if (@to_collapse > 1) {
+ my @collapsed;
+ while (@to_collapse) {
+ $self->_merge_result(\@collapsed, shift @to_collapse);
+ }
+ }
+=cut
+
+ my $mepref_structs = $self->_collapse_result($attrs->{as}, \@row, $keep_collapsing)
or return ();
- my @new = $self->result_class->inflate_result($self->result_source, @$info);
- @new = $self->{_attrs}{record_filter}->(@new)
- if exists $self->{_attrs}{record_filter};
- return @new;
+
+ my $rsrc = $self->result_source;
+ my $res_class = $self->result_class;
+ my $inflator = $res_class->can ('inflate_result');
+
+ my @objs =
+ $res_class->$inflator ($rsrc, @$mepref_structs);
+
+ if (my $f = $attrs->{record_filter}) {
+ @objs = map { $f->($_) } @objs;
+ }
+
+ return @objs;
}
+
sub _collapse_result {
- my ($self, $as_proto, $row) = @_;
+ my ( $self, $as_proto, $row_ref, $keep_collapsing ) = @_;
+ my $collapse = $self->_resolved_attrs->{collapse};
+ my $parser = $self->result_source->_mk_row_parser( $as_proto, $collapse );
+ my $result = [];
+ my $register = {};
+ my $rel_register = {};
- my @copy = @$row;
+ my @row = @$row_ref;
+ do {
+ my $row = $parser->( \@row );
- # 'foo' => [ undef, 'foo' ]
- # 'foo.bar' => [ 'foo', 'bar' ]
- # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
+ # init register
+ $self->_check_register( $register, $row ) unless ( keys %$register );
- my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
+ $self->_merge_result( $result, $row, $rel_register )
+ if ( !$collapse
+ || ( $collapse = $self->_check_register( $register, $row ) ) );
- my %collapse = %{$self->{_attrs}{collapse}||{}};
+ } while (
+ $collapse
+ && do { @row = $self->cursor->next; $self->{stashed_row} = \@row if @row; }
+
+ # run this as long as there is a next row and we are not yet done collapsing
+ );
+ return $result;
+}
- my @pri_index;
- # if we're doing collapsing (has_many prefetch) we need to grab records
- # until the PK changes, so fill @pri_index. if not, we leave it empty so
- # we know we don't have to bother.
- # the reason for not using the collapse stuff directly is because if you
- # had for e.g. two artists in a row with no cds, the collapse info for
- # both would be NULL (undef) so you'd lose the second artist
+# Taubenschlag
+sub _check_register {
+ my ( $self, $register, $obj ) = @_;
+ return undef unless ( ref $obj eq 'ARRAY' && ref $obj->[2] eq 'ARRAY' );
+ my @ids = @{ $obj->[2] };
+ while ( defined( my $id = shift @ids ) ) {
+ return $register->{$id} if ( exists $register->{$id} && !@ids );
+ $register->{$id} = @ids ? {} : $obj unless ( exists $register->{$id} );
+ $register = $register->{$id};
+ }
+ return undef;
+}
- # store just the index so we can check the array positions from the row
- # without having to contruct the full hash
+sub _merge_result {
+ my ( $self, $result, $row, $register ) = @_;
+ return @$result = @$row if ( @$result == 0 ); # initialize with $row
- if (keys %collapse) {
- my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
- foreach my $i (0 .. $#construct_as) {
- next if defined($construct_as[$i][0]); # only self table
- if (delete $pri{$construct_as[$i][1]}) {
- push(@pri_index, $i);
- }
- last unless keys %pri; # short circuit (Johnny Five Is Alive!)
+ my ( undef, $rels, $ids ) = @$result;
+ my ( undef, $new_rels, $new_ids ) = @$row;
+
+ my @rels = keys %{ { %{$rels||{} }, %{ $new_rels||{} } } };
+ foreach my $rel (@rels) {
+ $register = $register->{$rel} ||= {};
+
+ my $new_data = $new_rels->{$rel};
+ my $data = $rels->{$rel};
+ @$data = [@$data] unless ( ref $data->[0] eq 'ARRAY' );
+
+ $self->_check_register( $register, $data->[0] )
+ unless ( keys %$register );
+
+ if ( my $found = $self->_check_register( $register, $new_data ) ) {
+ $self->_merge_result( $found, $new_data, $register );
+ }
+ else {
+ push( @$data, $new_data );
}
}
+ return 1;
+}
+
+=begin
+
+# two arguments: $as_proto is an arrayref of column names,
+# $row_ref is an arrayref of the data. If none of the row data
+# is defined we return undef (that's copied from the old
+# _collapse_result). Next we decide whether we need to collapse
+# the resultset (i.e. we prefetch something) or not. $collapse
+# indicates that. The do-while loop will run once if we do not need
+# to collapse the result and will run as long as _merge_result returns
+# a true value. It will return undef if the current added row does not
+# match the previous row. A bit of stashing and cursor magic is
+# required so that the cursor is not mixed up.
+
+# "$rows" is a bit misleading. In the end, there should only be one
+# element in this arrayref.
- # no need to do an if, it'll be empty if @pri_index is empty anyway
+sub _collapse_result {
+ my ( $self, $as_proto, $row_ref ) = @_;
+ my $has_def;
+ for (@$row_ref) {
+ if ( defined $_ ) {
+ $has_def++;
+ last;
+ }
+ }
+ return undef unless $has_def;
+
+ my $collapse = $self->_resolved_attrs->{collapse};
+ my $rows = [];
+ my @row = @$row_ref;
+ do {
+ my $i = 0;
+ my $row = { map { $_ => $row[ $i++ ] } @$as_proto };
+ $row = $self->result_source->_parse_row($row, $collapse);
+ unless ( scalar @$rows ) {
+ push( @$rows, $row );
+ }
+ $collapse = undef unless ( $self->_merge_result( $rows, $row ) );
+ } while (
+ $collapse
+ && do { @row = $self->cursor->next; $self->{stashed_row} = \@row if @row; }
+ );
+
+ return $rows->[0];
- my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
+}
+
+# _merge_result accepts an arrayref of rows objects (again, an arrayref of two elements)
+# and a row object which should be merged into the first object.
+# First we try to find out whether $row is already in $rows. If this is the case
+# we try to merge them by iteration through their relationship data. We call
+# _merge_result again on them, so they get merged.
+
+# If we don't find the $row in $rows, we append it to $rows and return undef.
+# _merge_result returns 1 otherwise (i.e. $row has been found in $rows).
+
+sub _merge_result {
+ my ( $self, $rows, $row ) = @_;
+ my ( $columns, $rels ) = @$row;
+ my $found = undef;
+ foreach my $seen (@$rows) {
+ my $match = 1;
+ foreach my $column ( keys %$columns ) {
+ if ( defined $seen->[0]->{$column} ^ defined $columns->{$column}
+ or defined $columns->{$column}
+ && $seen->[0]->{$column} ne $columns->{$column} )
+ {
+
+ $match = 0;
+ last;
+ }
+ }
+ if ($match) {
+ $found = $seen;
+ last;
+ }
+ }
+ if ($found) {
+ foreach my $rel ( keys %$rels ) {
+ my $old_rows = $found->[1]->{$rel};
+ $self->_merge_result(
+ ref $found->[1]->{$rel}->[0] eq 'HASH' ? [ $found->[1]->{$rel} ]
+ : $found->[1]->{$rel},
+ ref $rels->{$rel}->[0] eq 'HASH' ? [ $rels->{$rel}->[0], $rels->{$rel}->[1] ]
+ : $rels->{$rel}->[0]
+ );
- my @const_rows;
+ my $attrs = $self->_resolved_attrs;
+ my ($keep_collapsing, $set_ident) = @{$attrs}{qw/collapse _collapse_ident/};
+
+ # FIXME this is temporary, need to calculate in _resolved_attrs
+ $set_ident ||= { me => [ $self->result_source->_pri_cols ], pref => {} };
+
+ my @cur_row = @$row_ref;
+ my (@to_collapse, $last_ident);
+
+ do {
+ my $row_hr = { map { $as_proto->[$_] => $cur_row[$_] } (0 .. $#$as_proto) };
+
+ # see if we are switching to another object
+ # this can be turned off and things will still work
+ # since _merge_prefetch knows about _collapse_ident
+# my $cur_ident = [ @{$row_hr}{@$set_ident} ];
+ my $cur_ident = [];
+ $last_ident ||= $cur_ident;
+
+# if ($keep_collapsing = Test::Deep::eq_deeply ($cur_ident, $last_ident)) {
+# push @to_collapse, $self->result_source->_parse_row (
+# $row_hr,
+# );
+# }
+ } while (
+ $keep_collapsing
+ &&
+ do { @cur_row = $self->cursor->next; $self->{stashed_row} = \@cur_row if @cur_row; }
+ );
- do { # no need to check anything at the front, we always want the first row
+ die Dumper \@to_collapse;
- my %const;
- foreach my $this_as (@construct_as) {
- $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
+ # attempt collapse all rows with same collapse identity
+ if (@to_collapse > 1) {
+ my @collapsed;
+ while (@to_collapse) {
+ $self->_merge_result(\@collapsed, shift @to_collapse);
}
+ @to_collapse = @collapsed;
+ }
- push(@const_rows, \%const);
+ # still didn't fully collapse
+ $self->throw_exception ('Resultset collapse failed (theoretically impossible). Maybe a wrong collapse_ident...?')
+ if (@to_collapse > 1);
- } until ( # no pri_index => no collapse => drop straight out
- !@pri_index
- or
- do { # get another row, stash it, drop out if different PK
+ return $to_collapse[0];
+}
- @copy = $self->cursor->next;
- $self->{stashed_row} = \@copy;
- # last thing in do block, counts as true if anything doesn't match
+# two arguments: $as_proto is an arrayref of 'as' column names,
+# $row_ref is an arrayref of the data. The do-while loop will run
+# once if we do not need to collapse the result and will run as long as
+# _merge_result returns a true value. It will return undef if the
+# current added row does not match the previous row, which in turn
+# means we need to stash the row for the subsequent ->next call
+sub _collapse_result {
+ my ( $self, $as_proto, $row_ref ) = @_;
- # check xor defined first for NULL vs. NOT NULL then if one is
- # defined the other must be so check string equality
+ my $attrs = $self->_resolved_attrs;
+ my ($keep_collapsing, $set_ident) = @{$attrs}{qw/collapse _collapse_ident/};
- grep {
- (defined $pri_vals{$_} ^ defined $copy[$_])
- || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
- } @pri_index;
- }
- );
+ die Dumper [$as_proto, $row_ref, $keep_collapsing, $set_ident ];
- my $alias = $self->{attrs}{alias};
- my $info = [];
- my %collapse_pos;
+ my @cur_row = @$row_ref;
+ my (@to_collapse, $last_ident);
- my @const_keys;
+ do {
+ my $row_hr = { map { $as_proto->[$_] => $cur_row[$_] } (0 .. $#$as_proto) };
- foreach my $const (@const_rows) {
- scalar @const_keys or do {
- @const_keys = sort { length($a) <=> length($b) } keys %$const;
- };
- foreach my $key (@const_keys) {
- if (length $key) {
- my $target = $info;
- my @parts = split(/\./, $key);
- my $cur = '';
- my $data = $const->{$key};
- foreach my $p (@parts) {
- $target = $target->[1]->{$p} ||= [];
- $cur .= ".${p}";
- if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) {
- # collapsing at this point and on final part
- my $pos = $collapse_pos{$cur};
- CK: foreach my $ck (@ckey) {
- if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) {
- $collapse_pos{$cur} = $data;
- delete @collapse_pos{ # clear all positioning for sub-entries
- grep { m/^\Q${cur}.\E/ } keys %collapse_pos
- };
- push(@$target, []);
- last CK;
- }
- }
- }
- if (exists $collapse{$cur}) {
- $target = $target->[-1];
- }
- }
- $target->[0] = $data;
- } else {
- $info->[0] = $const->{$key};
- }
- }
+ # see if we are switching to another object
+ # this can be turned off and things will still work
+ # since _merge_prefetch knows about _collapse_ident
+# my $cur_ident = [ @{$row_hr}{@$set_ident} ];
+ my $cur_ident = [];
+ $last_ident ||= $cur_ident;
+
+# if ($keep_collapsing = eq_deeply ($cur_ident, $last_ident)) {
+# push @to_collapse, $self->result_source->_parse_row (
+# $row_hr,
+# );
+# }
+ } while (
+ $keep_collapsing
+ &&
+ do { @cur_row = $self->cursor->next; $self->{stashed_row} = \@cur_row if @cur_row; }
+ );
+
+ # attempt collapse all rows with same collapse identity
+}
+=cut
+
+# Takes an arrayref of me/pref pairs and a new me/pref pair that should
+# be merged on a preexisting matching me (or should be pushed into $merged
+# as a new me/pref pair for further invocations). It should be possible to
+# use this function to collapse complete ->all results, provided _collapse_result() is adjusted
+# to provide everything to this sub not to barf when $merged contains more than one
+# arrayref)
+sub _merge_prefetch {
+ my ($self, $merged, $next_row) = @_;
+
+ unless (@$merged) {
+ push @$merged, $next_row;
+ return;
}
- return $info;
}
=head2 result_source
# if we multi-prefetch we group_by something unique, as this is what we would
# get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
- if ( keys %{$attrs->{collapse}} ) {
+ if ( $attrs->{collapse} ) {
$sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
$rsrc->_identifying_column_set || $self->throw_exception(
'Unable to construct a unique group_by criteria properly collapsing the '
$self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
}
- return @{ $self->get_cache } if $self->get_cache;
+ if (my $c = $self->get_cache) {
+ return @$c;
+ }
- my @obj;
+ my @objects;
- if (keys %{$self->_resolved_attrs->{collapse}}) {
+ if ($self->_resolved_attrs->{collapse}) {
# Using $self->cursor->all is really just an optimisation.
# If we're collapsing has_many prefetches it probably makes
# very little difference, and this is cleaner than hacking
- # _construct_object to survive the approach
+ # _construct_objects to survive the approach
$self->cursor->reset;
my @row = $self->cursor->next;
while (@row) {
- push(@obj, $self->_construct_object(@row));
+ push(@objects, $self->_construct_objects(@row));
@row = (exists $self->{stashed_row}
? @{delete $self->{stashed_row}}
: $self->cursor->next);
}
} else {
- @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
+ @objects = map { $self->_construct_objects(@$_) } $self->cursor->all;
}
- $self->set_cache(\@obj) if $self->{attrs}{cache};
+ $self->set_cache(\@objects) if $self->{attrs}{cache};
- return @obj;
+ return @objects;
}
=head2 reset
}
}
- $attrs->{collapse} ||= {};
- if ($attrs->{prefetch}) {
+ # generate selections based on the prefetch helper
+ my $prefetch;
+ $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
+ if defined $attrs->{prefetch};
+
+ if ($prefetch) {
$self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
if $attrs->{_dark_selector};
- my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
-
- my $prefetch_ordering = [];
+ $attrs->{collapse} = 1;
# this is a separate structure (we don't look in {from} directly)
# as the resolver needs to shift things off the lists to work
}
}
- my @prefetch =
- $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
+ my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
# we need to somehow mark which columns came from prefetch
if (@prefetch) {
push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
+ }
- push( @{$attrs->{order_by}}, @$prefetch_ordering );
- $attrs->{_collapse_order_by} = \@$prefetch_ordering;
+ # run through the resulting joinstructure (starting from our current slot)
+ # and unset collapse if proven unnesessary
+ if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
+
+ if (@{$attrs->{from}} > 1) {
+
+ # find where our table-spec starts and consider only things after us
+ my @fromlist = @{$attrs->{from}};
+ while (@fromlist) {
+ my $t = shift @fromlist;
+ $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
+ last if ($t->{-alias} && $t->{-alias} eq $alias);
+ }
+
+ for (@fromlist) {
+ $attrs->{collapse} = ! $_->[0]{-is_single}
+ and last;
+ }
+ }
+ else {
+ # no joins - no collapse
+ $attrs->{collapse} = 0;
+ }
}
projects / dbsrgits/DBIx-Class.git / blobdiff