PlanCache.clearPlansByQuery()

Definition

  • PlanCache.clearPlansByQuery(, , )
  • Clears the cached query plans for the specified query shape.

The method is only available from the plan cache object of a specific collection; i.e.

  1. db.collection.getPlanCache().clearPlansByQuery( <query>, <projection>, <sort> )

The PlanCache.clearPlansByQuery() method accepts thefollowing parameters:

ParameterTypeDescriptionquerydocumentThe query predicate of the query shape. Only the structureof the predicate, including the field names, are significant to theshape; the values in the query predicate are insignificant.projectiondocumentOptional. The projection associated with the query shape. Required ifspecifying the sort parameter.sortdocumentOptional. The sort associated with the query shape.

To see the query shapes for which cached query plans exist, seeList Query Shapes.

Required Access

On systems running with authorization, a user must have access thatincludes the planCacheWrite action.

Example

If a collection orders has the following query shape:

  1. {
  2.   "query" : { "qty" : { "$gt" : 10 } },
  3.   "sort" : { "ord_date" : 1 },
  4.   "projection" : { },
  5.   "queryHash" : "9AAD95BE" // Available starting in MongoDB 4.2
  6. }

The following operation removes the query plan cached for the shape:

  1. db.orders.getPlanCache().clearPlansByQuery(
  2.    { "qty" : { "$gt" : 10 } },
  3.    { },
  4.    { "ord_date" : 1 }
  5. )

See also