Re: Key joins - Mailing list pgsql-hackers

Hi hackers,

the attached patch is rebased on master. We also decided to drop the 
FILTER (WHERE ...) syntax, to avoid further discussions about that 
syntax hold back the patch itself.

The biggest change is the syntax change affecting the whole chain, but 
mostly our first commit. FOR KEY now names a table on both sides of the 
arrow, left operand first: a JOIN b FOR KEY a_tab (id) <- b_tab (a_id) 
replaces the old FOR KEY (a_id) -> a_tab (id), which named only the 
referenced table. The arrow still points from the referencing side to 
the referenced side. This moves the nice canonical form from all left 
arrows to all forward right arrows. This lead to a lot of mechanical 
changes in the tests. I did not review all of them by hand.

This patch also patches the debug section of pg_rewrite_query (the 
roundtrip eq check). Because proofDependencies are never written, 
we skip the serialization tests for FOR KEY JOIN dependencies. This is 
not done to address any live bugs, but avoid failing tests with 
debug_write_read_parse_plan_trees enabled. This is part of the Record 
and revalidate member of the series.

Regards
Arne