[Dbix-class] Complex table joins

[Matt S Trout]

On Mon, May 21, 2007 at 11:39:27AM +0100, Richard Jones wrote:
> I've got table joins working OK where base table_1 (me) contains foreign 
> keys to 3 other tables (table_2, table_3 & table_4).  So the 'base' (me) 
> table_1 contains 3 'belongs_to' relationships, and tables_ 2, 3 & 4 each 
> contain a 'has_many' relationship with the base table. Then:
> 
> my $rs = $c->model('Schema::Foo')->search( $where_href, # WHERE clause
>  {
>    select => qw( table1.id table2.field table3.something_else etc ),
>    join   => [ qw/table_2 table_3 table_4/ ],

The join attribute takes relationship names as defined in your classes; you
-may- make some of these the same as the table name but that's none of DBIC's
business.

The -only- place DBIx::Class takes a table name is in the ->table() statement.

If you think of anything anywhere else as a table name, you'll run into
problems because it isn't.

I think you'll find if you see it as

  join => [ qw(belongs_to_1, belongs_to_2), { belongs_to_3 => 'has_many_1' } ]

not only will your code work but everything will be much clearer.

-- 
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