Getting the right result is the first and foremost consideration while writing an SQL statement. After that, it is important to ensure that the statement is convenient for the current scenario. Multiple statements can be used to attain the same result. But, it is always one statement that draws the most suitable result for a given condition.

Whenever you start with Oracle SQL performance tuning, do not forget that SQL is a sequence of Parse (object resolution and syntax check), Implementation (necessary reads and writes) and Fetch (row results extracted, recorded, grouped and returned). The tuning of an SQL statement basically means decreasing one or more of them. 

Usually, Parse is the most time and asset consuming step. Parse overhead can be limited by the utilization of Procedures/Operation, Functions, Packages, Views, and so on. 

Insufficient execution can have a negative cost-related impact on your business. A poor performing framework and application can bring about client disappointment, decreased efficiency, and increased expenses. It is completely important that the framework's performance is working in the best way possible.

Here are some of the best tips that can help in increasing an SQL statement’s effectiveness. They may not have any significant effect on a specific situation. 

1. A point to remember is that SQL query performance tuning should be done only after you are sure that your code is accurate. Know that there is an inevitable back-and-forth between composing efficient SQL and reasonable SQL. 
   
   
2. If you are going to repeat an SQL statement, make sure that it is composed in a similar manner so as to encourage efficient reuse. 

3. Composing best rehearses: all SQL action words in capitalized format, for example, SELECT; separate all words with a space; all SQL action words start on another line; SQL action words adjusted right or left inside the initial action word; assign and retain aliases for tables; utilize table aliases and when a query includes multiple tables at once, attach all column names with their aliases. Just stay consistent; that is the number one rule.  

4. Use bind variables: The estimations of bind variables need not be the same for two statements to be viewed as indistinguishable. Bind variables are not replaced until a statement has been effectively parsed. 

5. Make use of a standard strategy to deal with table aliases. In case two similar SQL statements change on the grounds that a similar table has two distinct aliases, at that point the SQL is unique and won't be shared or re-utilized.

6. If a query includes multiple tables, it is advisable to make use of aliases along with prefixing every column name by its alias. This diminishes parse time and allows you to prevent syntax mistakes that may occur in the future such as somebody adding a column to one of the tables with a similar name as a column in another table.

Stay tuned for much such database performance tuning tips. In case of queries, you may contact one of our team members at Tosska Technology Limited and we’d be more than glad to help you.