• DBA,  Performance

    Performance Tuning Steps Query by looking an execution plan and effectiveness of the index Part 2

    How to read execution plan to improve poorly performing queries Execution plan is optimizer’s calculation of how the query will be executed by creating the best low-cost query plan (if it is already in the cache, it will reuse).  SQL server is cost based optimizer.  Meaning, the optimizer decides based on CPU, I/O and statistics etc and creates a plan and returns the results. Up to date statistics is very important one to create a more accurate plan. We can view this in GUI and text both will be helpful, when the scenario come in.   Types:  Estimated and Actual execution plan – both will be helpful. Estimated plan: It…

  • DBA,  Performance

    Performance Tuning Steps a Query by looking an execution plan and effectiveness of the index creation Part-1

    The index is very important and powerful object in the database. It is an optional and secondary object for the table. It will speed up the data return time by navigating the B-tree structure, like a book’s index. In General, index tuning is important one, putting a right index will speed up the code.  Please read this post for finding symptoms, where you have issue at server or database or query level.  Most of the time, the query will be the issue. Once, you have long running query start tuning it. In this post, I am going to share the usage and effectiveness of index from low level to high…