my ($self, $from, $select, $where, $attrs) = @_;
$self->throw_exception ('Nothing to prefetch... how did we get here?!')
- if not @{$attrs->{_prefetch_select}};
+ if not @{$attrs->{_prefetch_selector_range}};
$self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute')
if (ref $from ne 'ARRAY' || ref $from->[0] ne 'HASH' || ref $from->[1] ne 'ARRAY');
delete $outer_attrs->{$_} for qw/where bind rows offset group_by having/;
my $inner_attrs = { %$attrs };
- delete $inner_attrs->{$_} for qw/for collapse _prefetch_select _collapse_order_by select as/;
+ delete $inner_attrs->{$_} for qw/for collapse _prefetch_selector_range _collapse_order_by select as/;
# bring over all non-collapse-induced order_by into the inner query (if any)
# on the outside we substitute any function for its alias
my $outer_select = [ @$select ];
my $inner_select = [];
- for my $i (0 .. ( @$outer_select - @{$outer_attrs->{_prefetch_select}} - 1) ) {
+
+ my ($p_start, $p_end) = @{$outer_attrs->{_prefetch_selector_range}};
+ for my $i (0 .. $p_start - 1, $p_end + 1 .. $#$outer_select) {
my $sel = $outer_select->[$i];
if (ref $sel eq 'HASH' ) {
group_by => ['dummy'], %$inner_attrs,
});
- # if a multi-type join was needed in the subquery - add a group_by to simulate the
- # collapse in the subq
+ my $inner_aliastypes =
+ $self->_resolve_aliastypes_from_select_args( $inner_from, $inner_select, $where, $inner_attrs );
+
+ # if a multi-type non-selecting (only restricting) join was needed in the subquery
+ # add a group_by to simulate the collapse in the subq
if (
! $inner_attrs->{group_by}
and
- first { ! $_->[0]{-is_single} } (@{$inner_from}[1 .. $#$inner_from])
+ first {
+ $inner_aliastypes->{restricting}{$_}
+ and
+ ! $inner_aliastypes->{selecting}{$_}
+ } ( keys %{$inner_aliastypes->{multiplying}||{}} )
) {
- $inner_attrs->{group_by} = $self->_group_over_selection (
+ my $unprocessed_order_chunks;
+ ($inner_attrs->{group_by}, $unprocessed_order_chunks) = $self->_group_over_selection (
$inner_from, $inner_select, $inner_attrs->{order_by}
);
+
+ $self->throw_exception (
+ 'A required group_by clause could not be constructed automatically due to a complex '
+ . 'order_by criteria. Either order_by columns only (no functions) or construct a suitable '
+ . 'group_by by hand'
+ ) if $unprocessed_order_chunks;
}
# we already optimized $inner_from above
# also throw in a group_by if restricting to guard against
# cross-join explosions
#
+ my $need_outer_group_by;
while (my $j = shift @$from) {
my $alias = $j->[0]{-alias};
}
elsif ($outer_aliastypes->{restricting}{$alias}) {
push @outer_from, $j;
- $outer_attrs->{group_by} ||= $outer_select unless $j->[0]{-is_single};
+ $need_outer_group_by ||= ! $j->[0]{-is_single};
}
}
# demote the outer_from head
$outer_from[0] = $outer_from[0][0];
+ if ($need_outer_group_by and ! $outer_attrs->{group_by}) {
+
+ my $unprocessed_order_chunks;
+ ($outer_attrs->{group_by}, $unprocessed_order_chunks) = $self->_group_over_selection (
+ \@outer_from, $outer_select, $outer_attrs->{order_by}
+ );
+
+ $self->throw_exception (
+ 'A required group_by clause could not be constructed automatically due to a complex '
+ . 'order_by criteria. Either order_by columns only (no functions) or construct a suitable '
+ . 'group_by by hand'
+ ) if $unprocessed_order_chunks;
+
+ }
+
# This is totally horrific - the $where ends up in both the inner and outer query
# Unfortunately not much can be done until SQLA2 introspection arrives, and even
# then if where conditions apply to the *right* side of the prefetch, you may have
# set up a botched SQLA
my $sql_maker = $self->sql_maker;
- local $sql_maker->{having_bind}; # these are throw away results
+ # these are throw away results, do not pollute the bind stack
+ local $sql_maker->{select_bind};
+ local $sql_maker->{where_bind};
+ local $sql_maker->{group_bind};
+ local $sql_maker->{having_bind};
# we can't scan properly without any quoting (\b doesn't cut it
# everywhere), so unless there is proper quoting set - use our
}),
],
selecting => [
- $self->_extract_order_columns ($attrs->{order_by}, $sql_maker),
$sql_maker->_recurse_fields ($select),
+ ( map { $_->[0] } $self->_extract_order_criteria ($attrs->{order_by}, $sql_maker) ),
],
};
return $aliases_by_type;
}
+# This is the engine behind { distinct => 1 }
sub _group_over_selection {
my ($self, $from, $select, $order_by) = @_;
my (@group_by, %group_index);
+ # the logic is: if it is a { func => val } we assume an aggregate,
+ # otherwise if \'...' or \[...] we assume the user knows what is
+ # going on thus group over it
for (@$select) {
if (! ref($_) or ref ($_) ne 'HASH' ) {
push @group_by, $_;
# add any order_by parts that are not already present in the group_by
# we need to be careful not to add any named functions/aggregates
- # i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
- for my $chunk ($self->_extract_order_columns($order_by)) {
+ # i.e. order_by => [ ... { count => 'foo' } ... ]
+ my @leftovers;
+ for ($self->_extract_order_criteria($order_by)) {
# only consider real columns (for functions the user got to do an explicit group_by)
- my $colinfo = $rs_column_list->{$chunk}
- or next;
+ if (@$_ != 1) {
+ push @leftovers, $_;
+ next;
+ }
+ my $chunk = $_->[0];
+ my $colinfo = $rs_column_list->{$chunk} or do {
+ push @leftovers, $_;
+ next;
+ };
$chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
push @group_by, $chunk unless $group_index{$chunk}++;
}
- return \@group_by;
+ return wantarray
+ ? (\@group_by, (@leftovers ? \@leftovers : undef) )
+ : \@group_by
+ ;
}
sub _resolve_ident_sources {
return $cond;
}
-sub _extract_order_columns {
+sub _extract_order_criteria {
my ($self, $order_by, $sql_maker) = @_;
my $parser = sub {
unless wantarray;
my @chunks;
- for my $chunk (map { ref $_ ? @$_ : $_ } ($sql_maker->_order_by_chunks ($order_by) ) ) {
- $chunk =~ s/\s+ (?: ASC|DESC ) \s* $//ix;
+ for ($sql_maker->_order_by_chunks ($order_by) ) {
+ my $chunk = ref $_ ? $_ : [ $_ ];
+ $chunk->[0] =~ s/\s+ (?: ASC|DESC ) \s* $//ix;
push @chunks, $chunk;
}
projects / dbsrgits/DBIx-Class.git / blobdiff