Database Related

Tips For Tuning SQL Indexes For Efficient Performance

The indexes are used for making queries run more rapidly by decreasing the time taken to look up data. However, the substitute for that enhanced performance is that indexes also take up space, and there should be some repairs done on the indexes to make sure that they keep on running efficiently. Here are a few suggestions, guidelines and tips on how to use as well as properly maintain indexes for improving the performance of SQL indexes.

  • Avoid Using Multiple indexes

Indexes take up a lot of space. Thus, having a number of indexes can damage the performance because of the impact of space. For instance, if you try to do an Insert or an Update on a table that has several indexes, then there could be a big impact on performance because of the fact that all of the indexes will need to be updated also. You should follow the rule of not creating more than 3 or 4 indexes on one table.

  • Don’t Include Columns That Are Updated Repeatedly In An Index

If you are creating an index on a column that is updated repeatedly, then this means that the index will need to be updated whenever the column is updated. This process is done by the DBMS, so that the index stays consistent as well as current with the columns that belong to that index. Therefore, the amount of ‘writes’ is amplified two-fold, first time, when column is updated and the second time when the index updates itself. This is why; consider avoiding addition of columns that are updated in your index frequently.

  • Boost Performance By Creating Indexes On Foreign Key Column

Since joins are done between foreign and primary key pairs, thus having an index on the foreign key column can actually enhance the performance of join. In addition, the index also allows some optimizers to exercise other procedures of joining tables also.

  • Speed Up Queries By Creating Indexes For Columns That Are Used In Predicates Repeatedly

Analyze your SQL queries to find out the columns that are used in the WHERE predicate frequently. You should add those columns to an index, in case they are already not the part of an index. This is because an index on columns that are used in predicates repeatedly will help boost up your queries.

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