SQL Server query optimizer is an efficient engine that plays an important role in producing an efficient query execution plan for a query. By default, the optimizer decides the eligibility for parallel operation by creating a parallel query plan. Many times, this may not be an efficient plan based on the optimization goals that are specific to an application; thus, using the plan guide process is a recommended method. In such cases, the query plan can be optimized or tailor-made based on the response time, disk IO, memory, and CPU.
The troubleshooting aspects of query performance involve the review of many areas such as design, table indexing, and query execution. In case of running a third-party application tool where we are limited to modify or make any changes to queries that are causing performance problems the plan guides are helpful as they allow applying hints to the query without having a need to change...