ob_vector_search_strategy

Overview

ob_vector_search_strategy is used to control the query strategy during vector index queries.

Privilege requirements

• Query parameters

  Both the sys tenant and all user tenants can query this parameter using the SHOW PARAMETERS statement or the GV$OB_PARAMETERS view.

• Modify parameters

  Both the sys tenant and user tenants can modify this parameter.

Attributes

Usage instructions

• To ensure response time, set ob_vector_search_strategy to LATENCY_FIRST.
• For scenarios that are not time-sensitive and require a high recall rate, you can set it to RECALL_FIRST.
• When set to LATENCY_FIRST, it operates in response-first mode or fast mode. Users prefer quick result return with relatively stable RT.
• When set to RECALL_FIRST, it operates in result-first mode or depth-first search mode. The system strives to retrieve at least K matching records, even if this significantly slows down some queries.

Configuration example

Set the query strategy for vector indexes to response time first.

obclient> ALTER SYSTEM SET ob_vector_search_strategy = 'LATENCY_FIRST';