useless where clause on osm_type slows down the requests

[etienneJr]

Hi!
When a make a request with a filter by tag like way[leisure=playground], the parser writes this :

WITH _ab09a6067869338c0051f44462ec1eb829a19506 AS (
  SELECT * FROM way WHERE
    osm_type = 'w' AND
    (tags?'leisure' AND tags->>'leisure' = 'playground')
)

and for nwr[leisure=playground] :

WITH _bd1c8670f2520febe2cfb475addef794b2090256 AS (
  SELECT * FROM nwr WHERE
    osm_type = ANY (ARRAY['n', 'w', 'r']) AND
    (tags?'leisure' AND tags->>'leisure' = 'playground')
)

The where clause to filter on osm_type seems useless to me since it is redundant with the table on which the request is made.

Issue : it greatly increases the execution time since the osm_type column is created in the VIEW (at least for postgres backend) so it is not indexed.
[edit ] I myself have a problem reproducing this issue ... the requests have become faster once again, I don't understand why.

I imagine this clause is present here since it is usefull for other more complex requests ?