use List::Util 'first';
use Scalar::Util 'blessed';
-use Sub::Name 'subname';
+use DBIx::Class::_Util 'UNRESOLVABLE_CONDITION';
+use SQL::Abstract qw(is_plain_value is_literal_value);
use namespace::clean;
#
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
- );
+ my $switch_branch = $self->_find_join_path_to_node($from, $alias);
- # 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;
- }
- }
-
- # 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) = @_;
my @cols = (
( map { $_->[0] } $self->_extract_order_criteria($order_by) ),
- ( $where ? @{ $self->_extract_fixed_condition_columns($where) || [] } : () ),
- ) or return undef;
+ ( $where ? keys %{ $self->_extract_fixed_condition_columns($where) } : () ),
+ ) or return 0;
my $colinfo = $self->_resolve_column_info($ident, \@cols);
return keys %$colinfo
? $self->_columns_comprise_identifying_set( $colinfo, \@cols )
- : undef
+ : 0
;
}
return 1 if $src->_identifying_column_set($_);
}
- return undef;
+ return 0;
}
-# this is almost identical to the above, except it accepts only
+# this is almost similar to _order_by_is_stable, except it takes
# a single rsrc, and will succeed only if the first portion of the order
# by is stable.
# returns that portion as a colinfo hashref on success
-sub _main_source_order_by_portion_is_stable {
- my ($self, $main_rsrc, $order_by, $where) = @_;
+sub _extract_colinfo_of_stable_main_source_order_by_portion {
+ my ($self, $attrs) = @_;
+
+ my $nodes = $self->_find_join_path_to_node($attrs->{from}, $attrs->{alias});
- die "Huh... I expect a blessed result_source..."
- if ref($main_rsrc) eq 'ARRAY';
+ 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}
+ : ()
+ }
+ keys %{ $self->_extract_fixed_condition_columns($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
: { $w[0] => undef }
;
}
- elsif ( ref $w[0] ) {
- return \@w;
- }
- elsif ( @w == 2 ) {
+ elsif ( @w == 2 and ! ref $w[0]) {
if ( ( $w[0]||'' ) =~ /^\-and$/i ) {
return (ref $w[1] eq 'HASH' or ref $w[1] eq 'ARRAY')
? $self->_collapse_cond($w[1], (ref $w[1] eq 'ARRAY') )
return $self->_collapse_cond({ @w });
}
}
+ else {
+ return { -or => \@w };
+ }
}
else {
# not a hash not an array
return { '' => $where };
}
- # catchall, some of the things above fall through
- return $where;
+ die 'should not get here';
}
sub _collapse_cond_unroll_pairs {
if (ref $rhs eq 'HASH' and ! keys %$rhs) {
# FIXME - SQLA seems to be doing... nothing...?
}
+ elsif (ref $rhs eq 'HASH' and keys %$rhs == 1 and exists $rhs->{-ident}) {
+ push @conds, { $lhs => { '=', $rhs } };
+ }
+ elsif (ref $rhs eq 'HASH' and keys %$rhs == 1 and exists $rhs->{-value} and is_plain_value $rhs->{-value}) {
+ push @conds, { $lhs => $rhs->{-value} };
+ }
elsif (ref $rhs eq 'HASH' and keys %$rhs == 1 and exists $rhs->{'='}) {
- for my $p ($self->_collapse_cond_unroll_pairs([ [ $lhs => $rhs->{'='} ] ])) {
-
- # extra sanity check
- if (keys %$p > 1) {
- require Data::Dumper::Concise;
- local $Data::Dumper::Deepcopy = 1;
- $self->throw_exception(
- "Internal error: unexpected collapse unroll:"
- . Data::Dumper::Concise::Dumper { in => { $lhs => $rhs }, out => $p }
- );
- }
+ if( is_literal_value $rhs->{'='}) {
+ push @conds, { $lhs => $rhs };
+ }
+ else {
+ for my $p ($self->_collapse_cond_unroll_pairs([ [ $lhs => $rhs->{'='} ] ])) {
+
+ # extra sanity check
+ if (keys %$p > 1) {
+ require Data::Dumper::Concise;
+ local $Data::Dumper::Deepcopy = 1;
+ $self->throw_exception(
+ "Internal error: unexpected collapse unroll:"
+ . Data::Dumper::Concise::Dumper { in => { $lhs => $rhs }, out => $p }
+ );
+ }
- my ($l, $r) = %$p;
+ my ($l, $r) = %$p;
- push @conds, ( ! ref $r or overload::Method($r, '""' ) )
- ? { $l => $r }
- : { $l => { '=' => $r } }
- ;
+ push @conds, ( ! length ref $r or is_plain_value($r) )
+ ? { $l => $r }
+ : { $l => { '=' => $r } }
+ ;
+ }
}
}
elsif (ref $rhs eq 'ARRAY') {
return @conds;
}
-
-# returns an arrayref of column names which *definitely* have some
-# sort of non-nullable *single* equality requested in the given condition
-# specification. This is used to figure out if a resultset is
-# constrained to a column which is part of a unique constraint,
-# which in turn allows us to better predict how ordering will behave
-# etc.
+# Analyzes a given condition and attempts to extract all columns
+# with a definitive fixed-condition criteria. Returns a hashref
+# of k/v pairs suitable to be passed to set_columns(), with a
+# MAJOR CAVEAT - multi-value (contradictory) equalities are still
+# represented as a reference to the UNRESOVABLE_CONDITION constant
+# The reason we do this is that some codepaths only care about the
+# codition being stable, as opposed to actually making sense
+#
+# The normal mode is used to figure out if a resultset is constrained
+# to a column which is part of a unique constraint, which in turn
+# allows us to better predict how ordering will behave etc.
+#
+# With the optional "consider_nulls" boolean argument, the function
+# is instead used to infer inambiguous values from conditions
+# (e.g. the inheritance of resultset conditions on new_result)
#
-# this is a rudimentary, incomplete, and error-prone extractor
-# however this is OK - it is conservative, and if we can not find
-# something that is in fact there - the stack will recover gracefully
+my $undef_marker = \ do{ my $x = 'undef' };
sub _extract_fixed_condition_columns {
- my $self = shift;
- my $where_hash = $self->_collapse_cond(shift);
-
- my $res;
- for my $c (keys %$where_hash) {
- if (defined (my $v = $where_hash->{$c}) ) {
- if (
- ! ref $v
- or
- (ref $v eq 'HASH' and keys %$v == 1 and defined $v->{'='} and (
- ! ref $v->{'='}
- or
- ref $v->{'='} eq 'SCALAR'
- or
- ( ref $v->{'='} eq 'REF' and ref ${$v->{'='}} eq 'ARRAY' )
- or
- overload::Method($v->{'='}, '""')
- ))
- ) {
- $res->{$c} = 1;
+ my ($self, $where, $consider_nulls) = @_;
+ my $where_hash = $self->_collapse_cond($_[1]);
+
+ my $res = {};
+ my ($c, $v);
+ for $c (keys %$where_hash) {
+ my $vals;
+
+ if (!defined ($v = $where_hash->{$c}) ) {
+ $vals->{$undef_marker} = $v if $consider_nulls
+ }
+ elsif (
+ ref $v eq 'HASH'
+ and
+ keys %$v == 1
+ ) {
+ if (exists $v->{-value}) {
+ if (defined $v->{-value}) {
+ $vals->{$v->{-value}} = $v->{-value}
+ }
+ elsif( $consider_nulls ) {
+ $vals->{$undef_marker} = $v->{-value};
+ }
}
- elsif (ref $v eq 'ARRAY' and ($v->[0]||'') eq '-and') {
- $res->{$_} = 1 for map { @{ $self->_extract_fixed_condition_columns({ $c => $_ }) } } @{$v}[1..$#$v];
+ # do not need to check for plain values - _collapse_cond did it for us
+ elsif(ref $v->{'='} and is_literal_value($v->{'='}) ) {
+ $vals->{$v->{'='}} = $v->{'='};
}
}
+ elsif (
+ ! length ref $v
+ or
+ is_plain_value ($v)
+ ) {
+ $vals->{$v} = $v;
+ }
+ elsif (ref $v eq 'ARRAY' and ($v->[0]||'') eq '-and') {
+ for ( @{$v}[1..$#$v] ) {
+ my $subval = $self->_extract_fixed_condition_columns({ $c => $_ }, 'consider nulls'); # always fish nulls out on recursion
+ next unless exists $subval->{$c}; # didn't find anything
+ $vals->{defined $subval->{$c} ? $subval->{$c} : $undef_marker} = $subval->{$c};
+ }
+ }
+
+ if (keys %$vals == 1) {
+ ($res->{$c}) = (values %$vals)
+ unless !$consider_nulls and exists $vals->{$undef_marker};
+ }
+ elsif (keys %$vals > 1) {
+ $res->{$c} = UNRESOLVABLE_CONDITION;
+ }
}
- return [ sort keys %$res ];
+ $res;
}
1;
projects / dbsrgits/DBIx-Class.git / blobdiff