Heiko Gruner wrote:
Hi,
I am looking for some hints on a problem of hardcoding a relationship to
a multicolumn key in a different table:
My App Package is defined with a PK "appid".
It needs to get some entries from the Maps Package,
wheras the Maps table has a multicolumn key (fixedid and appid).
The appid columns of both tables would match 1:1.
But the "foreign.fixedid" needs to match '14'
(other Schema/Applications use other values of the fixedid in Maps).
How would i hardcode this value of "14" into this relationship ?
---------------------------------
__PACKAGE__->has_many( maps => 'Project::Schema::Maps',
{ 'foreign.fixedid' => 'self.workaroundid',
'foreign.appid' => 'self.appid'}, );
---
workaround: inserted an extra column "workaroundid" with identical data
values ('14') for the whole App table :-(
You might try creating the relationship accessor yourself in a custom
ResultSet class. First create a partial relationship using the
key-to-key mapping and a bogus name:
__PACKAGE__->has_many( map_rows => 'Project::Schema::Maps',
{ 'foreign.appid' => 'self.appid'}, );
(The name "map_rows" isn't very good, but I couldn't think of anything
better....) Then create a custom Project::ResultSet::App class that
explicitly defines the methods has_many would have generated:
sub maps {
return shift->search_related('map_rows', { fixedid => 14 });
}
sub maps_rs { return shift->maps->search_rs }
Of course, you also have to create the corresponding belongs_to
relationship in the Maps class:
__PACKAGE__->belongs_to( app_row => 'Project::Schema::App',
{ 'foreign.appid' => 'self.appid'}, );
Then, just for completeness, your custom Project::ResultSet::Maps should
probably include:
sub app {
my $self = shift;
return $self->fixedid == 14
? $self->app_row
: undef;
# or you could die, throw an exception, etc
}
Somebody holler if I'm going the wrong way with this!
HTH,
Jason
--
Jason Gottshall
[email protected]
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