When using row level security, GIN and GIST indexes appear to get ignored. Is this expected behavior? Can I change the query to get PostgreSQL using the index? For example, with RLS enabled, this query:
select * from search where search like '%yo'
Creates this query plan:
"Seq Scan on search (cost=0.00..245.46 rows=1 width=163)"
" Filter: (((tenant_name)::name = CURRENT_USER) AND (search ~~ '%yo'::text))"
" Filter: (((tenant_name)::name = CURRENT_USER) AND (search ~~ '%yo'::text))"
Running this same query with the owner of the table, thereby disabling RLS, the index gets used as expected:
"Bitmap Heap Scan on search (cost=4.49..96.33 rows=44 width=163)"
" Recheck Cond: (search ~~ '%yo'::text)"
" -> Bitmap Index Scan on search__gist (cost=0.00..4.48 rows=44 width=0)"
" Index Cond: (search ~~ '%yo'::text)"
" Recheck Cond: (search ~~ '%yo'::text)"
" -> Bitmap Index Scan on search__gist (cost=0.00..4.48 rows=44 width=0)"
" Index Cond: (search ~~ '%yo'::text)"
I see the same behavior with more complex queries, switching to GIN index, more complex RLS rules, using word_similarity instead of like, using full text search and larger data sets (e.g. 100k rows). This is on PostgreSQL v11.1 on Windows 10.
--
Derek
