Hi
I have a database that is migrated from sql server 2012 to sql server 2016
When I change the compatibility to 2016 which is 130 ...we have so many performance issues with queries.
When I switch either the Legacy Cardinality estimator ON or switch the compatibility to 2012.The performance with queries is good. (But I dont want to do this because I will loose the SQL engine features of 2016)
I have done some research on Query store to help with this type of situation.
>Enable the Query store
>Left the compatibility to 2012
>run the queries
>then change the compatibility to 2016
>run the queries (to check for different plans)
>Force the query plan in Query Store.
I have followed these steps I wrote above for the expensive queries.
Now My questions to you all experts are
Will I have to enable the query store enabled all the time to keep this forced Query plan?
The answer is YES I guess
There is a situation where I cannot force a plan as it says NO_PLAN under last_force_failure_reason_desc
There are no changes in Indexes I checked...what schema changes would have effected this?
Suggest me the best ways/tips to migrate please
Kind Regards,
Chinna