Sql Programming Tutorials, Guides & Best Practices

Indexes are data structures that improve the speed of data retrieval operations on a database table. They are similar to the index in a book, which allows you to quickly find specific topics without scanning every page. In MySQL, indexes can be applied to columns to speed up queries involving those columns.

Indexes can be created when a table is first created or added later using the CREATE INDEX statement.

Monitoring MySQL database performance is crucial for maintaining efficient and reliable database operations. By keeping an eye on performance metrics, you can identify bottlenecks, optimize queries, and ensure that your database is running smoothly. This tutorial will cover various tools and techniques for monitoring MySQL performance.

• Basic understanding of MySQL and SQL operations.
• Access to a MySQL server.
• Familiarity with command-line tools and basic server administration.

• Select Type: Type of query (simple, primary, subquery, etc.).
• Table: The table accessed by the query.
• Type: Type of access (e.g., index, ALL, ref, const).
• Possible Keys: Indexes considered by the optimizer.
• Key: Index used for the query.
• Rows: Estimated number of rows examined.
• Extra: Additional information, such as whether a temporary table or file sort is used.

Use EXPLAIN to identify full table scans (type = ALL) and optimize them by adding appropriate indexes.

SELECT name FROM employees ORDER BY salary DESC LIMIT 10;

• Query Caching: Enable if supported by your DBMS.