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How do I force SQL Server to use a specific execution plan?
Forcing Execution Plan
- Get the OLD execution plan from old server. You can get this from SSMS or DMV’s or Profiler.
- At this point you have 1.) Query text that needs to be tuned 2.)
- To verify weather the plan guide is getting picked up, you can 1.) either run profiler with “Plan guide successful” event or 2.)
What are the permissions required to view the execution plan?
A SQL DBA usually has all permissions by being part of the SYSADMIN fixed server role, so a DBA usually can view the SQL Server execution plan. Logins which have permissions like SYSADMIN, db_owner, and dbcreator can see the execution plan.
How do you force a query to particular index?
Index Hints: How to Force Query Plans
- Setting up the World Example Database.
- Forcing Join Order.
- Forcing Usage of a Specific Index for the WHERE Clause. USE INDEX: Use a Limited Set of Indexes.
- Forcing an Index to be Used for ORDER BY or GROUP BY.
- Forcing Usage of Temporary Tables.
- Optimizer Switch.
- See Also.
Can a query store enforce an execution plan?
Query Store has a mechanism to enforce Query Optimizer to use certain execution plan. However, there are some limitations that can prevent a plan to be enforced. First, if the plan contains following constructions: Insert bulk statement. Azure SQL Database and SQL Server 2019 support plan forcing for static and fast forward cursors.
Can you force SQL Server to go through desired execution plan?
Yes but try it, if you don’t recompile for the second query that has “more” data to come, the generated plan will depend on whatever was in the cache before it. You might get the same plan as if the @personIdwas 10(compiled for @personId = 10) unless you recompile.
How to have only one query execution plan evaluated?
If what you really want is to have only one query execution plan evaluated when you are doing this branch logic, instead of both (as the query optimizer will do when executing the procedure) then you must separate it into two different sub-procedures and call them from a parent-wrapper-procedure.
When is Plan marked as forced in SQL Server?
Plan is marked as forced when user executes stored procedure sys.sp_query_store_force_plan. Forcing mechanism does not guarantee that exactly this plan will be used for the query referenced by query_id. Plan forcing causes query to be compiled again and typically produces exactly the same or similar plan to the plan referenced by plan_id.