DMVs used to analyze the execution plan cache

You can obtain a lot of information about the execution plans in the procedure cache by accessing various dynamic management objects.

sys.dm_exec_cached_plans: obtain information about the execution plans in the plan cache.

sys.dm_exec_query_plan(plan_handle): retrieve the XML representation of the plan.

sys.dm_exec_sql_text(plan_handle): retrieve the original query text.

sys.dm_exec_query_stats: get aggregate performance metrics about the cached plan.

sys.dm_exec_requests: see execution plans for queries that are currently executing.

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