my $sub_attrs = { %$attrs };
- # these can not go in the subquery, and there is no point of ordering it
- delete $sub_attrs->{$_} for qw/collapse select as order_by/;
+ # extra selectors do not go in the subquery and there is no point of ordering it
+ delete $sub_attrs->{$_} for qw/collapse prefetch_select select as order_by/;
# if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
# clobber old group_by regardless
my @obj;
- # TODO: don't call resolve here
if (keys %{$self->_resolved_attrs->{collapse}}) {
# if ($self->{attrs}{prefetch}) {
# 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
+ $self->cursor->reset;
my @row = $self->cursor->next;
while (@row) {
push(@obj, $self->_construct_object(@row));
: [ $attrs->{order_by} ]
);
}
- else {
- $attrs->{order_by} = [];
- }
if ($attrs->{group_by} and ! ref $attrs->{group_by}) {
$attrs->{group_by} = [ $attrs->{group_by} ];
my @prefetch =
$source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
- push( @{ $attrs->{select} }, map { $_->[0] } @prefetch );
- push( @{ $attrs->{as} }, map { $_->[1] } @prefetch );
+ $attrs->{prefetch_select} = [ map { $_->[0] } @prefetch ];
+ push @{ $attrs->{select} }, @{$attrs->{prefetch_select}};
+ push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
push( @{ $attrs->{order_by} }, @$prefetch_ordering );
$attrs->{_collapse_order_by} = \@$prefetch_ordering;
}
}
- my @limit;
- if ($attrs->{software_limit} ||
- $sql_maker->_default_limit_syntax eq "GenericSubQ") {
- $attrs->{software_limit} = 1;
- } else {
+ # adjust limits
+ if (
+ $attrs->{software_limit}
+ ||
+ $sql_maker->_default_limit_syntax eq "GenericSubQ"
+ ) {
+ $attrs->{software_limit} = 1;
+ }
+ else {
$self->throw_exception("rows attribute must be positive if present")
if (defined($attrs->{rows}) && !($attrs->{rows} > 0));
# MySQL actually recommends this approach. I cringe.
$attrs->{rows} = 2**48 if not defined $attrs->{rows} and defined $attrs->{offset};
+ }
- if ($attrs->{rows} && keys %{$attrs->{collapse}}) {
- ($ident, $select, $where, $attrs)
- = $self->_adjust_select_args_for_limited_prefetch ($ident, $select, $where, $attrs);
- }
- else {
- push @limit, $attrs->{rows}, $attrs->{offset};
- }
+ my @limit;
+
+ # see if we need to tear the prefetch apart (either limited has_many or grouped prefetch)
+ # otherwise delegate the limiting to the storage, unless software limit was requested
+ if (
+ ( $attrs->{rows} && keys %{$attrs->{collapse}} )
+ ||
+ ( $attrs->{group_by} && @{$attrs->{group_by}} &&
+ $attrs->{prefetch_select} && @{$attrs->{prefetch_select}} )
+ ) {
+ $select = [ @$select ]; # it will get mangled
+ ($ident, $select, $where, $attrs)
+ = $self->_adjust_select_args_for_complex_prefetch ($ident, $select, $where, $attrs);
+ }
+ elsif (! $attrs->{software_limit} ) {
+ push @limit, $attrs->{rows}, $attrs->{offset};
}
###
(qw/order_by group_by having _virtual_order_by/ )
};
-
$sql_maker->{for} = delete $attrs->{for};
return ('select', $attrs->{bind}, $ident, $bind_attrs, $select, $where, $order, @limit);
}
-sub _adjust_select_args_for_limited_prefetch {
+sub _adjust_select_args_for_complex_prefetch {
my ($self, $from, $select, $where, $attrs) = @_;
- if ($attrs->{group_by} and @{$attrs->{group_by}}) {
- $self->throw_exception ('Prefetch with limit (rows/offset) is not supported on resultsets with a group_by attribute');
- }
-
$self->throw_exception ('Prefetch with limit (rows/offset) is not supported on resultsets with a custom from attribute')
if (ref $from ne 'ARRAY');
-
# separate attributes
my $sub_attrs = { %$attrs };
- delete $attrs->{$_} for qw/where bind rows offset/;
- delete $sub_attrs->{$_} for qw/for collapse select order_by/;
+ delete $attrs->{$_} for qw/where bind rows offset group_by having/;
+ delete $sub_attrs->{$_} for qw/for collapse prefetch_select _collapse_order_by select as/;
my $alias = $attrs->{alias};
- # create subquery select list
- my $sub_select = [ grep { $_ =~ /^$alias\./ } @{$attrs->{select}} ];
+ # create subquery select list - loop only over primary columns
+ my $sub_select = [];
+ for my $i (0 .. @{$attrs->{select}} - @{$attrs->{prefetch_select}} - 1) {
+ my $sel = $attrs->{select}[$i];
+
+ # alias any functions to the dbic-side 'as' label
+ # adjust the outer select accordingly
+ if (ref $sel eq 'HASH' && !$sel->{-select}) {
+ $sel = { -select => $sel, -as => $attrs->{as}[$i] };
+ $select->[$i] = join ('.', $attrs->{alias}, $attrs->{as}[$i]);
+ }
+
+ push @$sub_select, $sel;
+ }
# bring over all non-collapse-induced order_by into the inner query (if any)
# the outer one will have to keep them all
+ delete $sub_attrs->{order_by};
if (my $ord_cnt = @{$attrs->{order_by}} - @{$attrs->{_collapse_order_by}} ) {
$sub_attrs->{order_by} = [
- @{$attrs->{order_by}}[ 0 .. ($#{$attrs->{order_by}} - $ord_cnt - 1) ]
+ @{$attrs->{order_by}}[ 0 .. $ord_cnt - 1]
];
}
# away _any_ branches of the join tree that are:
# 1) not mentioned in the condition/order
# 2) left-join leaves (or left-join leaf chains)
- # Most of the join ocnditions will not satisfy this, but for real
+ # Most of the join conditions will not satisfy this, but for real
# complex queries some might, and we might make some RDBMS happy.
#
#
# the dot comes from some weirdness in collapse
# remove after the rewrite
if ($attrs->{collapse}{".$alias"}) {
- $sub_attrs->{group_by} = $sub_select;
+ $sub_attrs->{group_by} ||= $sub_select;
last;
}
}
projects / dbsrgits/DBIx-Class.git / commitdiff