# GenSubQ is slow enough as it is, just emulating things
# like in other cases is not wise - make the user work
# to shoot their DBA in the foot
- my $supplied_order = delete $rs_attrs->{order_by} or $self->throw_exception (
+ $self->throw_exception (
'Generic Subquery Limit does not work on resultsets without an order. Provide a stable, '
. 'main-table-based order criteria.'
- );
+ ) unless $rs_attrs->{order_by};
my $usable_order_colinfo = $main_rsrc->storage->_extract_colinfo_of_stable_main_source_order_by_portion(
- $main_rsrc,
- $supplied_order,
- $rs_attrs->{where},
- ) or $self->throw_exception(
- 'Generic Subquery Limit can not work with order criteria based on sources other than the current one'
+ $rs_attrs
+ );
+
+ $self->throw_exception(
+ 'Generic Subquery Limit can not work with order criteria based on sources other than the main one'
+ ) if (
+ ! keys %{$usable_order_colinfo||{}}
+ or
+ grep
+ { $_->{-source_alias} ne $rs_attrs->{alias} }
+ (values %$usable_order_colinfo)
);
###
###
### we need to know the directions after we figured out the above - reextract *again*
### this is eyebleed - trying to get it to work at first
+ my $supplied_order = delete $rs_attrs->{order_by};
+
my @order_bits = do {
local $self->{quote_char};
local $self->{order_bind};
sub _inner_join_to_node {
my ($self, $from, $alias) = @_;
- # subqueries and other oddness are naturally not supported
- return $from if (
- ref $from ne 'ARRAY'
- ||
- @$from <= 1
- ||
- ref $from->[0] ne 'HASH'
- ||
- ! $from->[0]{-alias}
- ||
- $from->[0]{-alias} eq $alias # this last bit means $alias is the head of $from - nothing to do
- );
-
- # find the current $alias in the $from structure
- my $switch_branch;
- JOINSCAN:
- for my $j (@{$from}[1 .. $#$from]) {
- if ($j->[0]{-alias} eq $alias) {
- $switch_branch = $j->[0]{-join_path};
- last JOINSCAN;
- }
- }
+ my $switch_branch = $self->_find_join_path_to_node($from, $alias);
- # something else went quite wrong
- return $from unless $switch_branch;
+ return $from unless @{$switch_branch||[]};
# So it looks like we will have to switch some stuff around.
# local() is useless here as we will be leaving the scope
return \@new_from;
}
+sub _find_join_path_to_node {
+ my ($self, $from, $target_alias) = @_;
+
+ # subqueries and other oddness are naturally not supported
+ return undef if (
+ ref $from ne 'ARRAY'
+ ||
+ ref $from->[0] ne 'HASH'
+ ||
+ ! defined $from->[0]{-alias}
+ );
+
+ # no path - the head is the alias
+ return [] if $from->[0]{-alias} eq $target_alias;
+
+ for my $i (1 .. $#$from) {
+ return $from->[$i][0]{-join_path} if ( ($from->[$i][0]{-alias}||'') eq $target_alias );
+ }
+
+ # something else went quite wrong
+ return undef;
+}
+
sub _extract_order_criteria {
my ($self, $order_by, $sql_maker) = @_;
# by is stable.
# returns that portion as a colinfo hashref on success
sub _extract_colinfo_of_stable_main_source_order_by_portion {
- my ($self, $main_rsrc, $order_by, $where) = @_;
+ my ($self, $attrs) = @_;
- die "Huh... I expect a blessed result_source..."
- if ref($main_rsrc) eq 'ARRAY';
+ my $nodes = $self->_find_join_path_to_node($attrs->{from}, $attrs->{alias});
+
+ return unless defined $nodes;
my @ord_cols = map
{ $_->[0] }
- ( $self->_extract_order_criteria($order_by) )
+ ( $self->_extract_order_criteria($attrs->{order_by}) )
;
return unless @ord_cols;
- my $colinfos = $self->_resolve_column_info($main_rsrc);
+ my $valid_aliases = { map { $_ => 1 } (
+ $attrs->{from}[0]{-alias},
+ map { values %$_ } @$nodes,
+ ) };
- for (0 .. $#ord_cols) {
- if (
- ! $colinfos->{$ord_cols[$_]}
- or
- $colinfos->{$ord_cols[$_]}{-result_source} != $main_rsrc
- ) {
- $#ord_cols = $_ - 1;
- last;
- }
- }
+ my $colinfos = $self->_resolve_column_info($attrs->{from});
- # we just truncated it above
- return unless @ord_cols;
+ my ($colinfos_to_return, $seen_main_src_cols);
- my $order_portion_ci = { map {
- $colinfos->{$_}{-colname} => $colinfos->{$_},
- $colinfos->{$_}{-fq_colname} => $colinfos->{$_},
- } @ord_cols };
+ for my $col (@ord_cols) {
+ # if order criteria is unresolvable - there is nothing we can do
+ my $colinfo = $colinfos->{$col} or last;
- # since all we check here are the start of the order_by belonging to the
- # top level $rsrc, a present identifying set will mean that the resultset
- # is ordered by its leftmost table in a stable manner
- #
- # RV of _identifying_column_set contains unqualified names only
- my $unqualified_idset = $main_rsrc->_identifying_column_set({
- ( $where ? %{
- $self->_resolve_column_info(
- $main_rsrc, $self->_extract_fixed_condition_columns($where)||[]
- )
- } : () ),
- %$order_portion_ci
- }) or return;
-
- my $ret_info;
- my %unqualified_idcols_from_order = map {
- $order_portion_ci->{$_} ? ( $_ => $order_portion_ci->{$_} ) : ()
- } @$unqualified_idset;
-
- # extra optimization - cut the order_by at the end of the identifying set
- # (just in case the user was stupid and overlooked the obvious)
- for my $i (0 .. $#ord_cols) {
- my $col = $ord_cols[$i];
- my $unqualified_colname = $order_portion_ci->{$col}{-colname};
- $ret_info->{$col} = { %{$order_portion_ci->{$col}}, -idx_in_order_subset => $i };
- delete $unqualified_idcols_from_order{$ret_info->{$col}{-colname}};
-
- # we didn't reach the end of the identifying portion yet
- return $ret_info unless keys %unqualified_idcols_from_order;
+ # if we reached the end of the allowed aliases - also nothing we can do
+ last unless $valid_aliases->{$colinfo->{-source_alias}};
+
+ $colinfos_to_return->{$col} = $colinfo;
+
+ $seen_main_src_cols->{$colinfo->{-colname}} = 1
+ if $colinfo->{-source_alias} eq $attrs->{alias};
}
- die 'How did we get here...';
+ # FIXME the condition may be singling out things on its own, so we
+ # conceivable could come back wi "stable-ordered by nothing"
+ # not confient enough in the parser yet, so punt for the time being
+ return unless $seen_main_src_cols;
+
+ my $main_src_fixed_cols_from_cond = [ $attrs->{where}
+ ? (
+ map
+ {
+ ( $colinfos->{$_} and $colinfos->{$_}{-source_alias} eq $attrs->{alias} )
+ ? $colinfos->{$_}{-colname}
+ : ()
+ }
+ @{$self->_extract_fixed_condition_columns($attrs->{where}) || []}
+ )
+ : ()
+ ];
+
+ return $attrs->{result_source}->_identifying_column_set([
+ keys %$seen_main_src_cols,
+ @$main_src_fixed_cols_from_cond,
+ ]) ? $colinfos_to_return : ();
}
# Attempts to flatten a passed in SQLA condition as much as possible towards
projects / dbsrgits/DBIx-Class.git / commitdiff