=head1 OVERLOADING
If a resultset is used in a numeric context it returns the L</count>.
- However, if it is used in a booleand context it is always true. So if
+ However, if it is used in a boolean context it is always true. So if
you want to check if a resultset has any results use C<if $rs != 0>.
C<if $rs> will always be true.
# in ::Relationship::Base::search_related (the row method), and furthermore
# the relationship is of the 'single' type. This means that the condition
# provided by the relationship (already attached to $self) is sufficient,
- # as there can be only one row in the databse that would satisfy the
+ # as there can be only one row in the database that would satisfy the
# relationship
}
else {
}
# Run the query
- my $rs = $self->search ($query, $attrs);
- if (keys %{$rs->_resolved_attrs->{collapse}}) {
+ my $rs = $self->search ($query, {result_class => $self->result_class, %$attrs});
+ if ($rs->_resolved_attrs->{collapse}) {
my $row = $rs->next;
carp "Query returned more than one row" if $rs->next;
return $row;
=head2 search_related_rs
This method works exactly the same as search_related, except that
- it guarantees a restultset, even in list context.
+ it guarantees a resultset, even in list context.
=cut
=item B<Note>
- As of 0.08100, this method enforces the assumption that the preceeding
+ As of 0.08100, this method enforces the assumption that the preceding
query returns only one row. If more than one row is returned, you will receive
a warning:
my $attrs = $self->_resolved_attrs_copy;
- if (keys %{$attrs->{collapse}}) {
+ if ($attrs->{collapse}) {
$self->throw_exception(
'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
);
return @new;
}
-sub _collapse_result {
- my ($self, $as_proto, $row) = @_;
-
- my @copy = @$row;
-
- # 'foo' => [ undef, 'foo' ]
- # 'foo.bar' => [ 'foo', 'bar' ]
- # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
-
- my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
-
- my %collapse = %{$self->{_attrs}{collapse}||{}};
-
- 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.
+# 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. $collapse
+# indicates that. The do-while loop will run once if we do not need
+# to collapse the result and will run as long as _merge_result returns
+# a true value. It will return undef if the current added row does not
+# match the previous row. A bit of stashing and cursor magic is
+# required so that the cursor is not mixed up.
- # the reason for not using the collapse stuff directly is because if you
- # had for e.g. two artists in a row with no cds, the collapse info for
- # both would be NULL (undef) so you'd lose the second artist
+# "$rows" is a bit misleading. In the end, there should only be one
+# element in this arrayref.
- # store just the index so we can check the array positions from the row
- # without having to contruct the full hash
-
- if (keys %collapse) {
- my %pri = map { ($_ => 1) } $self->result_source->primary_columns;
- 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!)
+sub _collapse_result {
+ my ( $self, $as_proto, $row_ref ) = @_;
+ my $has_def;
+ for (@$row_ref) {
+ if ( defined $_ ) {
+ $has_def++;
+ last;
+ }
}
- }
-
- # no need to do an if, it'll be empty if @pri_index is empty anyway
-
- my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
-
- my @const_rows;
+ 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; }
+ );
- do { # no need to check anything at the front, we always want the first row
+ return $rows->[0];
- my %const;
+}
- foreach my $this_as (@construct_as) {
- $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
+# _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]
+ );
- push(@const_rows, \%const);
-
- } until ( # no pri_index => no collapse => drop straight out
- !@pri_index
- or
- do { # get another row, stash it, drop out if different PK
-
- @copy = $self->cursor->next;
- $self->{stashed_row} = \@copy;
-
- # last thing in do block, counts as true if anything doesn't match
-
- # check xor defined first for NULL vs. NOT NULL then if one is
- # defined the other must be so check string equality
-
- grep {
- (defined $pri_vals{$_} ^ defined $copy[$_])
- || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
- } @pri_index;
- }
- );
-
- my $alias = $self->{attrs}{alias};
- my $info = [];
-
- my %collapse_pos;
-
- my @const_keys;
-
- 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};
- }
+
+ }
+ else {
+ push( @$rows, $row );
+ return undef;
}
- }
- return $info;
+ return 1;
}
+
=head2 result_source
=over 4
if ($result_class) {
$self->ensure_class_loaded($result_class);
$self->_result_class($result_class);
+ $self->{attrs}{result_class} = $result_class if ref $self;
}
$self->_result_class;
}
# if we multi-prefetch we group_by primary keys only as this is what we would
# get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
- if ($attrs->{collapse}) {
- $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->primary_columns) ]
- if ( keys %{$attrs->{collapse}} ) {
++ if ( $attrs->{collapse} ) {
+ $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
}
- $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $sub_attrs);
+ $sub_attrs->{select} = $rsrc->storage->_subq_count_select ($rsrc, $attrs);
# this is so that the query can be simplified e.g.
# * ordering can be thrown away in things like Top limit
my @obj;
- if (keys %{$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
my $attrs = $self->_resolved_attrs_copy;
delete $attrs->{$_} for qw/collapse select as/;
- $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
+ $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->_pri_cols) ];
if ($needs_group_by_subq) {
# make sure no group_by was supplied, or if there is one - make sure it matches
],
},
{ artistid => 5, name => 'Angsty-Whiny Girl', cds => [
- { title => 'My parents sold me to a record company' ,year => 2005 },
+ { title => 'My parents sold me to a record company', year => 2005 },
{ title => 'Why Am I So Ugly?', year => 2006 },
{ title => 'I Got Surgery and am now Popular', year => 2007 }
],
[qw/artistid name/],
[100, 'A Formally Unknown Singer'],
[101, 'A singer that jumped the shark two albums ago'],
- [102, 'An actually cool singer.'],
+ [102, 'An actually cool singer'],
]);
Please note an important effect on your data when choosing between void and
B<keyed on the relationship name>. If the relationship is of type C<multi>
(L<DBIx::Class::Relationship/has_many>) - pass an arrayref of hashrefs.
The process will correctly identify columns holding foreign keys, and will
- transparrently populate them from the keys of the corresponding relation.
+ transparently populate them from the keys of the corresponding relation.
This can be applied recursively, and will work correctly for a structure
with an arbitrary depth and width, as long as the relationships actually
exists and the correct column data has been supplied.
}
}
else {
-
# otherwise we intialise select & as to empty
$attrs->{select} = [];
$attrs->{as} = [];
}
}
- $attrs->{collapse} ||= {};
if ( my $prefetch = delete $attrs->{prefetch} ) {
- $prefetch = $self->_merge_attr( {}, $prefetch );
+ $attrs->{collapse} = 1;
my $prefetch_ordering = [];
}
}
- my @prefetch =
- $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
+ my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering );
# we need to somehow mark which columns came from prefetch
$attrs->{_prefetch_select} = [ map { $_->[0] } @prefetch ];
$attrs->{_collapse_order_by} = \@$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);
+ }
+
+ if (@fromlist) {
+ $attrs->{collapse} = scalar grep { ! $_->[0]{-is_single} } (@fromlist);
+ }
+ }
+ else {
+ # no joins - no collapse
+ $attrs->{collapse} = 0;
+ }
+ }
+
# if both page and offset are specified, produce a combined offset
# even though it doesn't make much sense, this is what pre 081xx has
# been doing
will fail miserably.
To get around this limitation, you can supply literal SQL to your
- C<select> attibute that contains the C<AS alias> text, eg:
+ C<select> attribute that contains the C<AS alias> text, e.g.
select => [\'myfield AS alias']
C<prefetch> can be used with the following relationship types: C<belongs_to>,
C<has_one> (or if you're using C<add_relationship>, any relationship declared
with an accessor type of 'single' or 'filter'). A more complex example that
- prefetches an artists cds, the tracks on those cds, and the tags associted
+ prefetches an artists cds, the tracks on those cds, and the tags associated
with that artist is given below (assuming many-to-many from artists to tags):
my $rs = $schema->resultset('Artist')->search(
=back
- Specifes the maximum number of rows for direct retrieval or the number of
+ Specifies the maximum number of rows for direct retrieval or the number of
rows per page if the page attribute or method is used.
=head2 offset
return @{shift->_primaries||[]};
}
+ sub _pri_cols {
+ my $self = shift;
+ my @pcols = $self->primary_columns
+ or $self->throw_exception (sprintf(
+ 'Operation requires a primary key to be declared on %s via set_primary_key',
+ ref $self,
+ ));
+ return @pcols;
+ }
+
=head2 add_unique_constraint
=over 4
# in the supplied relationships.
sub _resolve_prefetch {
- my ($self, $pre, $alias, $alias_map, $order, $collapse, $pref_path) = @_;
+ my ($self, $pre, $alias, $alias_map, $order, $pref_path) = @_;
$pref_path ||= [];
if (not defined $pre) {
}
elsif( ref $pre eq 'ARRAY' ) {
return
- map { $self->_resolve_prefetch( $_, $alias, $alias_map, $order, $collapse, [ @$pref_path ] ) }
+ map { $self->_resolve_prefetch( $_, $alias, $alias_map, $order, [ @$pref_path ] ) }
@$pre;
}
elsif( ref $pre eq 'HASH' ) {
my @ret =
map {
- $self->_resolve_prefetch($_, $alias, $alias_map, $order, $collapse, [ @$pref_path ] ),
+ $self->_resolve_prefetch($_, $alias, $alias_map, $order, [ @$pref_path ] ),
$self->related_source($_)->_resolve_prefetch(
- $pre->{$_}, "${alias}.$_", $alias_map, $order, $collapse, [ @$pref_path, $_] )
+ $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] )
} keys %$pre;
return @ret;
}
"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 ".${as_prefix}"
- if (my ($fail) = grep { @{[$_ =~ m/\./g]} == $dots }
- keys %{$collapse}) {
- my ($last) = ($fail =~ /([^\.]+)$/);
- carp (
- "Prefetching multiple has_many rels ${last} and ${pre} "
- .(length($as_prefix)
- ? "at the same level (${as_prefix}) "
- : "at top level "
- )
- . 'will explode the number of row objects retrievable via ->next or ->all. '
- . 'Use at your own risk.'
- );
- }
+
#my @col = map { (/^self\.(.+)$/ ? ("${as_prefix}.$1") : ()); }
# values %{$rel_info->{cond}};
- $collapse->{".${as_prefix}${pre}"} = [ $rel_source->primary_columns ];
- # action at a distance. prepending the '.' allows simpler code
- # in ResultSet->_collapse_result
my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
keys %{$rel_info->{cond}};
my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY'
? @{$rel_info->{attrs}{order_by}}
-
+
: (defined $rel_info->{attrs}{order_by}
? ($rel_info->{attrs}{order_by})
: ()));
}
}
+# Takes a hashref of $sth->fetchrow values keyed to the corresponding
+# {as} dbic aliases, and splits it into a native columns hashref
+# (as in $row->get_columns), followed by any non-native (prefetched)
+# columns, presented in a nested structure resembling an HRI dump.
+# The structure is constructed taking into account relationship metadata
+# (single vs multi).
+# The resulting arrayref resembles the arguments to ::Row::inflate_result
+# For an example look at t/prefetch/_util.t
+#
+# The will collapse flag is for backwards compatibility only - if it is
+# set, all relationship row-parts are returned as hashes, even if some
+# of these relationships are has_many's
+#
+sub _parse_row {
+ my ( $self, $row, $will_collapse ) = @_;
+
+ my ($me, $pref);
+
+ foreach my $column ( keys %$row ) {
+ if ( $column =~ /^ ([^\.]+) \. (.*) $/x ) {
+ $pref->{$1}{$2} = $row->{$column};
+ }
+ else {
+ $me->{$column} = $row->{$column};
+ }
+ }
+
+ foreach my $rel ( keys %{$pref||{}} ) {
+ my $rel_info = $self->relationship_info($rel);
+
+ $pref->{$rel} =
+ $self->related_source($rel)->_parse_row( $pref->{$rel}, $will_collapse );
+
+ $pref->{$rel} = [ $pref->{$rel} ]
+ if ( $will_collapse && $rel_info->{attrs}{accessor} eq 'multi' );
+ }
+
+ return [ $me||{}, $pref||() ];
+}
+
=head2 related_source
=over 4
__PACKAGE__->column_info_from_storage(1);
Enables the on-demand automatic loading of the above column
- metadata from storage as neccesary. This is *deprecated*, and
+ metadata from storage as necessary. This is *deprecated*, and
should not be used. It will be removed before 1.0.
# Each of these methods need _determine_driver called before itself
# in order to function reliably. This is a purely DRY optimization
my @rdbms_specific_methods = qw/
+ deployment_statements
sqlt_type
build_datetime_parser
datetime_parser_type
In addition to the standard L<DBI|DBI/ATTRIBUTES_COMMON_TO_ALL_HANDLES>
L<connection|DBI/Database_Handle_Attributes> attributes, DBIx::Class recognizes
the following connection options. These options can be mixed in with your other
- L<DBI> connection attributes, or placed in a seperate hashref
+ L<DBI> connection attributes, or placed in a separate hashref
(C<\%extra_attributes>) as shown above.
Every time C<connect_info> is invoked, any previous settings for
=item name_sep
This only needs to be used in conjunction with C<quote_char>, and is used to
- specify the charecter that seperates elements (schemas, tables, columns) from
+ specify the character that separates elements (schemas, tables, columns) from
each other. In most cases this is simply a C<.>.
The consequences of not supplying this value is that L<SQL::Abstract>
=back
- Verifies that the the current database handle is active and ready to execute
- an SQL statement (i.e. the connection did not get stale, server is still
+ Verifies that the current database handle is active and ready to execute
+ an SQL statement (e.g. the connection did not get stale, server is still
answering, etc.) This method is used internally by L</dbh>.
=cut
my $rsrc = $rs->result_source;
# quick check if we got a sane rs on our hands
- my @pcols = $rsrc->primary_columns;
- unless (@pcols) {
- $self->throw_exception (
- sprintf (
- "You must declare primary key(s) on source '%s' (via set_primary_key) in order to update or delete complex resultsets",
- $rsrc->source_name || $rsrc->from
- )
- );
- }
+ my @pcols = $rsrc->_pri_cols;
my $sel = $rs->_resolved_attrs->{select};
$sel = [ $sel ] unless ref $sel eq 'ARRAY';
my ($rs, $op, $values) = @_;
my $rsrc = $rs->result_source;
- my @pcols = $rsrc->primary_columns;
+ my @pcols = $rsrc->_pri_cols;
my $guard = $self->txn_scope_guard;
# see if we need to tear the prefetch apart otherwise delegate the limiting to the
# storage, unless software limit was requested
if (
- #limited has_many
- ( $attrs->{rows} && keys %{$attrs->{collapse}} )
+ # limited collapsing has_many
+ ( $attrs->{rows} && $attrs->{collapse} )
||
# limited prefetch with RNO subqueries
(
#
sub _subq_count_select {
my ($self, $source, $rs_attrs) = @_;
- return $rs_attrs->{group_by} if $rs_attrs->{group_by};
+
+ if (my $groupby = $rs_attrs->{group_by}) {
+
+ my $avail_columns = $self->_resolve_column_info ($rs_attrs->{from});
+
+ my $sel_index;
+ for my $sel (@{$rs_attrs->{select}}) {
+ if (ref $sel eq 'HASH' and $sel->{-as}) {
+ $sel_index->{$sel->{-as}} = $sel;
+ }
+ }
+
+ my @selection;
+ for my $g_part (@$groupby) {
+ if (ref $g_part or $avail_columns->{$g_part}) {
+ push @selection, $g_part;
+ }
+ elsif ($sel_index->{$g_part}) {
+ push @selection, $sel_index->{$g_part};
+ }
+ else {
+ $self->throw_exception ("group_by criteria '$g_part' not contained within current resultset source(s)");
+ }
+ }
+
+ return \@selection;
+ }
my @pcols = map { join '.', $rs_attrs->{alias}, $_ } ($source->primary_columns);
return @pcols ? \@pcols : [ 1 ];
}
$self->_query_end($line);
};
- my @statements = $self->deployment_statements($schema, $type, undef, $dir, { %{ $sqltargs || {} }, no_comments => 1 } );
+ my @statements = $schema->deployment_statements($type, undef, $dir, { %{ $sqltargs || {} }, no_comments => 1 } );
if (@statements > 1) {
foreach my $statement (@statements) {
$deploy->( $statement );
This hook is to allow specific L<DBIx::Class::Storage> drivers to change the
way these aliases are named.
- The default behavior is C<"$relname_$join_count" if $join_count > 1>, otherwise
- C<"$relname">.
+ The default behavior is C<< "$relname_$join_count" if $join_count > 1 >>,
+ otherwise C<"$relname">.
=cut
projects / dbsrgits/DBIx-Class.git / commitdiff