# Oracle vector store ignores JSON Search Index when vector index exists
## What was going on
When I use similarity_search with a metadata filter and both a vector index and a JSON Search Index exist, the JSON index is never used. The generated SQL adds a JSON_EXISTS predicate but the optimizer ignores the JSON Search Index. The notebook was working earlier today before I restarted the kernel. Nothing else changed in the code between the working and broken runs.
## The fix that worked
The problem was the generated SQL was missing the optimizer hint that makes the database consider both indexes, so the JSON Search Index sat unused whenever a vector index existed. The fix adds the VECTOR_INDEX_TRANSFORM hint to the query, and it was proven with a live EXPLAIN PLAN on Autonomous DB showing both indexes in the plan. Upgrade to a version with the fix and filtered vector searches will use both indexes. Source: https://github.com/oracle/langchain-oracle/issues/130
## Where this came from
https://github.com/oracle/langchain-oracle/issues/130