———use
strict;
use
warnings;
=head1 NAME
DBIx::Class::ResultClass::HashRefInflator - Get raw hashrefs from a resultset
=head1 SYNOPSIS
use DBIx::Class::ResultClass::HashRefInflator;
my $rs = $schema->resultset('CD');
$rs->result_class('DBIx::Class::ResultClass::HashRefInflator');
while (my $hashref = $rs->next) {
...
}
OR as an attribute:
my $rs = $schema->resultset('CD')->search({}, {
result_class => 'DBIx::Class::ResultClass::HashRefInflator',
});
while (my $hashref = $rs->next) {
...
}
=head1 DESCRIPTION
DBIx::Class is faster than older ORMs like Class::DBI but it still isn't
designed primarily for speed. Sometimes you need to quickly retrieve the data
from a massive resultset, while skipping the creation of fancy result objects.
Specifying this class as a C<result_class> for a resultset will change C<< $rs->next >>
to return a plain data hash-ref (or a list of such hash-refs if C<< $rs->all >> is used).
There are two ways of applying this class to a resultset:
=over
=item *
Specify C<< $rs->result_class >> on a specific resultset to affect only that
resultset (and any chained off of it); or
=item *
Specify C<< __PACKAGE__->result_class >> on your source object to force all
uses of that result source to be inflated to hash-refs - this approach is not
recommended.
=back
=cut
##############
# NOTE
#
# Generally people use this to gain as much speed as possible. If a new &mk_hash is
# implemented, it should be benchmarked using the maint/benchmark_hashrefinflator.pl
# script (in addition to passing all tests of course :)
# This coderef is a simple recursive function
# Arguments: ($me, $prefetch, $is_root) from inflate_result() below
my
$mk_hash
;
$mk_hash
=
sub
{
my
$hash
= {
# the main hash could be an undef if we are processing a skipped-over join
$_
[0] ? %{
$_
[0]} : (),
# the second arg is a hash of arrays for each prefetched relation
map
{
$_
=> (
# null-branch or not
ref
$_
[1]->{
$_
} eq
$DBIx::Class::ResultSource::RowParser::Util::null_branch_class
?
ref
$_
[1]->{
$_
}[0] eq
'ARRAY'
? [] :
undef
:
ref
$_
[1]->{
$_
}[0] eq
'ARRAY'
? [
map
{
$mk_hash
->(
@$_
) || () } @{
$_
[1]->{
$_
}} ]
:
$mk_hash
->( @{
$_
[1]->{
$_
}} )
) } (
$_
[1] ?
keys
%{
$_
[1]} : ())
};
(
$_
[2] ||
keys
%$hash
) ?
$hash
:
undef
;
};
=head1 METHODS
=head2 inflate_result
Inflates the result and prefetched data into a hash-ref (invoked by L<DBIx::Class::ResultSet>)
=cut
##################################################################################
# inflate_result is invoked as:
# HRI->inflate_result ($resultsource_instance, $main_data_hashref, $prefetch_data_hashref)
sub
inflate_result {
return
$mk_hash
->(
$_
[2],
$_
[3],
'is_root'
);
}
1;
__END__
=head1 CAVEATS
=over
=item *
This will not work for relationships that have been prefetched. Consider the
following:
my $artist = $artitsts_rs->search({}, {prefetch => 'cds' })->first;
my $cds = $artist->cds;
$cds->result_class('DBIx::Class::ResultClass::HashRefInflator');
my $first = $cds->first;
C<$first> will B<not> be a hashref, it will be a normal CD row since
HashRefInflator only affects resultsets at inflation time, and prefetch causes
relations to be inflated when the master C<$artist> row is inflated.
=item *
Column value inflation, e.g., using modules like
L<DBIx::Class::InflateColumn::DateTime>, is not performed.
The returned hash contains the raw database values.
=back
=head1 FURTHER QUESTIONS?
Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
=head1 COPYRIGHT AND LICENSE
This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
redistribute it and/or modify it under the same terms as the
L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.