MongoDB Query Plan Cache Commands

MongoDB planCacheClear command

The planCacheClear command is used to remove the cached query plans for a collection. It declares the query shape to remove the cached query plan for that shape.

Syntax:

Command Fields

Example:

We have the following query shape:

The following code clears the query plan cached for the shape:

MongoDB planCacheClearFilters command

The planCacheClearFilters command removes index filters on a collection. We can also clear existing index filters with this command while index filters only exist for the duration of the server process and don't persist after shutdown.

Syntax:

Command Fields:

Example:

The books collection contains the following two filters:

The following command will remove the first index filter:

MongoDB planCacheListFilters command

The palncacheListFilters command lists the index filters associated with query shapes for a collection.

Syntax:

Command Field:

Example:

MongoDB palnCacheSetFilter command

This command set an index filter for a collection. It is the index filter that already exists for the query shape. The planCacheSetFilter overwrites the previous index filter.

Syntax:

Command Filters

Example:

The example creates an index filter on the books collection such that for queries that contains only of an equality match on the purchase field without any projection and sort.