MySQL indexes explained with WordPress query optimisation examples
Understand how MySQL indexes work and learn to add the right indexes to WordPress custom tables and meta queries to eliminate slow full-table scans.
MySQL stored procedures explained with WordPress database examples
Create MySQL stored procedures for batch WordPress database operations like orphan cleanup and category stats, and call them from wpdb.
MySQL views explained with WordPress database examples
Create MySQL views to encapsulate complex WordPress JOIN queries into reusable virtual tables you can query from PHP with wpdb.
Manage WordPress database migrations with dbDelta and versioned SQL scri ...
Build a reliable WordPress plugin migration system with dbDelta, version options and ordered migration functions that run automatically on update.
MySQL subqueries explained with WordPress database examples
Use MySQL IN, NOT EXISTS and derived table subqueries to filter and clean WordPress database records efficiently.
MySQL JOINs explained with WordPress database examples
Learn INNER JOIN, LEFT JOIN and multi-table joins with practical WordPress SQL examples for posts, meta and taxonomy tables.
MySQL transactions: use COMMIT and ROLLBACK in WordPress
Wrap multi-table inserts and updates in MySQL transactions with START TRANSACTION, COMMIT and ROLLBACK via $wpdb.
Aggregate and sort WordPress data with MySQL GROUP BY and ORDER BY
Use MySQL GROUP BY, ORDER BY, HAVING and aggregate functions to count and summarise WordPress database records.
Use EXPLAIN to find and fix slow MySQL queries
Learn how to read MySQL EXPLAIN output to identify missing indexes and eliminate full-table scans.