Inflates the first result without creating a cursor if the resultset has
any records in it; if not returns nothing. Used by L</find> as an optimisation.
+Can optionally take an additional condition *only* - this is a fast-code-path
+method; if you need to add extra joins or similar call ->search and then
+->single without a condition on the $rs returned from that.
+
=cut
sub single {
$attrs->{order_by} = [ $attrs->{order_by} ] if
$attrs->{order_by} and !ref($attrs->{order_by});
$attrs->{order_by} ||= [];
+
+ if(my $seladds = delete($attrs->{'+select'})) {
+ my @seladds = (ref($seladds) eq 'ARRAY' ? @$seladds : ($seladds));
+ $attrs->{select} = [
+ @{ $attrs->{select} },
+ map { (m/\./ || ref($_)) ? $_ : "${alias}.$_" } $seladds
+ ];
+ }
+ if(my $asadds = delete($attrs->{'+as'})) {
+ my @asadds = (ref($asadds) eq 'ARRAY' ? @$asadds : ($asadds));
+ $attrs->{as} = [ @{ $attrs->{as} }, @asadds ];
+ }
my $collapse = $attrs->{collapse} || {};
if (my $prefetch = delete $attrs->{prefetch}) {
$self->_resolve;
my $attrs = { %{ $self->{_attrs} } };
- if ($attrs->{distinct} && (my $group_by = $attrs->{group_by} || $attrs->{select})) {
+ if (my $group_by = delete $attrs->{group_by}) {
delete $attrs->{having};
my @distinct = (ref $group_by ? @$group_by : ($group_by));
# todo: try CONCAT for multi-column pk
$cond->{-and} = [];
my @cond = @{$self->{cond}{-and}};
- for (my $i = 0; $i < @cond - 1; $i++) {
+ for (my $i = 0; $i <= @cond - 1; $i++) {
my $entry = $cond[$i];
my %hash;
}
else {
$entry =~ /([^.]+)$/;
- $hash{$entry} = $cond[++$i];
+ $hash{$1} = $cond[++$i];
}
push @{$cond->{-and}}, \%hash;
attribute, the column names returned are storage-dependent. E.g. MySQL would
return a column named C<count(employeeid)> in the above example.
+=head2 +select
+
+=over 4
+
+Indicates additional columns to be selected from storage. Works the same as
+L<select> but adds columns to the selection.
+
+=back
+
+=head2 +as
+
+=over 4
+
+Indicates additional column names for those added via L<+select>.
+
+=back
+
=head2 as
=over 4
You can create your own accessors if required - see
L<DBIx::Class::Manual::Cookbook> for details.
+Please note: This will NOT insert an C<AS employee_count> into the SQL statement
+produced, it is used for internal access only. Thus attempting to use the accessor
+in an C<order_by> clause or similar will fail misrably.
+
=head2 join
=over 4
C<has_one> (or if you're using C<add_relationship>, any relationship declared
with an accessor type of 'single' or 'filter').
+=head2 page
+
+=over 4
+
+=item Value: $page
+
+=back
+
+Makes the resultset paged and specifies the page to retrieve. Effectively
+identical to creating a non-pages resultset and then calling ->page($page)
+on it.
+
+=head2 rows
+
+=over 4
+
+=item Value: $rows
+
+=back
+
+Specifes the maximum number of rows for direct retrieval or the number of
+rows per page if the page attribute or method is used.
+
+=head2 group_by
+
+=over 4
+
+=item Value: \@columns
+
+=back
+
+A arrayref of columns to group by. Can include columns of joined tables.
+
+ group_by => [qw/ column1 column2 ... /]
+
+=head2 having
+
+=over 4
+
+=item Value: $condition
+
+=back
+
+HAVING is a select statement attribute that is applied between GROUP BY and
+ORDER BY. It is applied to the after the grouping calculations have been
+done.
+
+ having => { 'count(employee)' => { '>=', 100 } }
+
+=head2 distinct
+
+=over 4
+
+=item Value: (0 | 1)
+
+=back
+
+Set to 1 to group by all columns.
+
+=head2 cache
+
+Set to 1 to cache search results. This prevents extra SQL queries if you
+revisit rows in your ResultSet:
+
+ my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
+
+ while( my $artist = $resultset->next ) {
+ ... do stuff ...
+ }
+
+ $rs->first; # without cache, this would issue a query
+
+By default, searches are not cached.
+
+For more examples of using these attributes, see
+L<DBIx::Class::Manual::Cookbook>.
+
=head2 from
=over 4
clauses.
NOTE: Use this on your own risk. This allows you to shoot off your foot!
+
C<join> will usually do what you need and it is strongly recommended that you
avoid using C<from> unless you cannot achieve the desired result using C<join>.
+And we really do mean "cannot", not just tried and failed. Attempting to use
+this because you're having problems with C<join> is like trying to use x86
+ASM because you've got a syntax error in your C. Trust us on this.
-In simple terms, C<from> works as follows:
+Now, if you're still really, really sure you need to use this (and if you're
+not 100% sure, ask the mailing list first), here's an explanation of how this
+works.
+The syntax is as follows -
+
+ [
+ { <alias1> => <table1> },
[
- { <alias> => <table>, -join_type => 'inner|left|right' }
- [] # nested JOIN (optional)
- { <table.column> => <foreign_table.foreign_key> }
- ]
+ { <alias2> => <table2>, -join_type => 'inner|left|right' },
+ [], # nested JOIN (optional)
+ { <table1.column1> => <table2.column2>, ... (more conditions) },
+ ],
+ # More of the above [ ] may follow for additional joins
+ ]
- JOIN
- <alias> <table>
- [JOIN ...]
- ON <table.column> = <foreign_table.foreign_key>
+ <table1> <alias1>
+ JOIN
+ <table2> <alias2>
+ [JOIN ...]
+ ON <table1.column1> = <table2.column2>
+ <more joins may follow>
An easy way to follow the examples below is to remember the following:
# SELECT child.* FROM person child
# INNER JOIN person father ON child.father_id = father.id
-=head2 page
-
-=over 4
-
-=item Value: $page
-
-=back
-
-Makes the resultset paged and specifies the page to retrieve. Effectively
-identical to creating a non-pages resultset and then calling ->page($page)
-on it.
-
-=head2 rows
-
-=over 4
-
-=item Value: $rows
-
-=back
-
-Specifes the maximum number of rows for direct retrieval or the number of
-rows per page if the page attribute or method is used.
-
-=head2 group_by
-
-=over 4
-
-=item Value: \@columns
-
-=back
-
-A arrayref of columns to group by. Can include columns of joined tables.
-
- group_by => [qw/ column1 column2 ... /]
-
-=head2 having
-
-=over 4
-
-=item Value: $condition
-
-=back
-
-HAVING is a select statement attribute that is applied between GROUP BY and
-ORDER BY. It is applied to the after the grouping calculations have been
-done.
-
- having => { 'count(employee)' => { '>=', 100 } }
-
-=head2 distinct
-
-=over 4
-
-=item Value: (0 | 1)
-
-=back
-
-Set to 1 to group by all columns.
-
-=head2 cache
-
-Set to 1 to cache search results. This prevents extra SQL queries if you
-revisit rows in your ResultSet:
-
- my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
-
- while( my $artist = $resultset->next ) {
- ... do stuff ...
- }
-
- $rs->first; # without cache, this would issue a query
-
-By default, searches are not cached.
-
-For more examples of using these attributes, see
-L<DBIx::Class::Manual::Cookbook>.
-
=cut
1;
projects / dbsrgits/DBIx-Class.git / blobdiff