This topic describes the requirements and suggestions on the use of cache in OceanBase Database.
If a field is frequently written by an application, such as a counter, we recommend that you make use of the write cache.
An execution plan that occupies more than 20 MB of memory is not added to the plan cache.
A distributed execution plan that involves multiple tables is not added to a plan cache.
Use a hint to control the plan cache.
The hint
/*+ USE_PLAN_CACHE(NONE)*/indicates that the plan cache is not used.The hint
/*+USE_PLAN_CACHE(DEFAULT)*/indicates that the plan cache is used.
Do not use hints, such as
FORCE INDEX,IGNORE INDEX,STRAIGHT_JOIN, andSQL_NO_CACHE, for SQL statements.