Copy-ready commandSQL JOIN — Basic Usage Help and Syntax
EXPLAIN SELECT u.name, d.name AS department FROM users u JOIN departments d ON d.id = u.department_id;Production warning
Help and syntax commands are generally read-only. The original command shown for context may change systems or data; review it before execution.
Requirements and permissions
- Requirements
- Appropriate database client and connection
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- Last reviewed
- 2026-07-31
Examples
Display the full reference
Requests an execution plan so indexes, scans, joins, and estimated work can be reviewed before tuning.
EXPLAIN SELECT u.name, d.name AS department FROM users u JOIN departments d ON d.id = u.department_id;Original command context
The original SQL JOIN — Basic Usage example is included for context. Review all parameters before using it in production.
SELECT u.name, d.name AS department FROM users u JOIN departments d ON d.id = u.department_id;Common errors
EXPLAIN syntax differs for this database engine
Use EXPLAIN ANALYZE only in a safe test environment, or consult the engine-specific execution-plan syntax.