Re: Index not used in certain nested views but not in others

Markus Demleitner <msdemlei@ari.uni-heidelberg.de> writes:
> You see, when creating the "big", 30-tables view, I do cast all
> columns to common types in the view statement that actually make up
> the view.  The original SQL fragments look like this:

>   SELECT
>     CAST(ssa_dstype AS text) AS dataproduct_type,
>     CAST(NULL AS text) AS dataproduct_subtype,
>     CAST(2 AS smallint) AS calib_level,
>     ...

> and have a common source, so I'd believe by the time the things end
> up in the view, they should type-align even though their source
> tables do not.

Oh, well, that's your problem.  The source tables' column types
need to match.  Otherwise the UNIONs don't get flattened and you
don't get indexscans.

            regards, tom lane