How can we optimize or increase the speed of a MySQL SELECT query?

Tips to Improve MySQL Query Performance

1. Optimize Your Database. You need to know how to design schemas to support efficient queries.
2. Optimize Joins. Reduce the join statements in queries.
3. Index All Columns Used in ‘where’, ‘order by’, and ‘group by’ Clauses. INDEXES.
4. Use Full-Text Searches.
5. MySQL Query Caching.

How can I speed up MySQL query execution?

MySQL has a built-in slow query log. To use it, open the my. cnf file and set the slow_query_log variable to “On.” Set long_query_time to the number of seconds that a query should take to be considered slow, say 0.2. Set slow_query_log_file to the path where you want to save the file.

How do I make SELECT queries faster?

How To Speed Up SQL Queries

1. Use column names instead of SELECT *
2. Avoid Nested Queries & Views.
3. Use IN predicate while querying Indexed columns.
4. Do pre-staging.
5. Use temp tables.
6. Use CASE instead of UPDATE.
7. Avoid using GUID.
8. Avoid using OR in JOINS.

How do I optimize a selected query in MySQL?

Optimize Queries With MySQL Query Optimization Guidelines

1. Avoid using functions in predicates.
2. Avoid using a wildcard (\%) at the beginning of a predicate.
3. Avoid unnecessary columns in SELECT clause.
4. Use inner join, instead of outer join if possible.
5. Use DISTINCT and UNION only if it is necessary.

What is SQL query optimization?

Query optimization is the overall process of choosing the most efficient means of executing a SQL statement. SQL is a nonprocedural language, so the optimizer is free to merge, reorganize, and process in any order. The database optimizes each SQL statement based on statistics collected about the accessed data.

What is slow query in MySQL?

The slow query log consists of SQL statements that take more than long_query_time seconds to execute and require at least min_examined_row_limit rows to be examined. The slow query log can be used to find queries that take a long time to execute and are therefore candidates for optimization.

How optimize MySQL query with multiple joins?

2 Answers

1. Check if you really have to select every column in all of the tables?
2. You may also want to consider reducing the load on the database by using caching applications like sphinxsearch and memcached.
3. Check none of your joins are to views rather than actual tables.