Know Your Basics SQL Performance{2}

by Stefan S
The article talks about to be good performance of database is starts with a proper formulated SQL. According to Mullins, 75% of poor relational performance is caused by “bad” SQL and application code. For those people are new to programming especially for relational database environment it is very hard to remember and determine the problem in SQL. The best way to learn the basic performance of SQL is to be efficient.

The first step we need to know is thinking about file-level processing instead of relationally. “Using code join instead of implementing cursors for every table, because join is optimized by the database management system and will return only the data that is needed to your program. Secondly always provide exact columns that you need to retrieve in the SELECT-list of each SQL SELECT statement like follow “SELECT *” because is to fine for quick but is bad practice for inclusion in application programs.” (Mullins, C. S. (2010)

Mullins also mention about building appropriates indexes for your queries is critically important. Check your query’s path and what indexes are available is a good habit to have optimal database.

We can relate this basic rules and performance to our class because when we are doing the project two we need to be more careful with our SQL statement, every detail counts. Bad SQL statement can jeopardize our project. We can imagine if we work for a company and we just try to do the sort cut, without knowing we can really destroy a valuable database.

In my opinion practicing with SQL commands is the only way to be good at it. In class we should have some sort of live practice with SQL statement, therefore we can really know hands on what method or the basic way we should approach SQL, because we can practice but sometimes is hard for us to determine whether we did the right way or the wrong way.

Mullins, C. S. (2010). SQL performance basics. Database Trends and Applications, 24(4), 29-29. Retrieved from