AUTO_INCREMENT

AUTO_INCREMENT is a SQL statement in the MySQL Specific category. MySQL auto-generates sequential integer values for this column. Commonly used with PRIMARY KEY. The syntax is column type AUTO_INCREMENT. It returns auto-generated integer. A typical example: CREATE TABLE users ( id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(100) ); INSERT INTO users (name) VALUES ('Alice'), ('Bob'); -- ids are automatically 1, 2, 3... A close relative is ENGINE, which specifies the MySQL storage engine. InnoDB (default) supports transactions and foreign keys. MyISAM is faster for read-heavy. A close relative is LAST_INSERT_ID(), which returns the AUTO_INCREMENT value generated by the most recent INSERT in the current connection. A close relative is ON DUPLICATE KEY UPDATE, which mySQL extension: if INSERT causes a duplicate key error, it performs an UPDATE instead. More about this category: MySQL-specific features — AUTO_INCREMENT, ENGINE, SHOW TABLES, LIMIT. Related MySQL Specific entries: ENGINE, LAST_INSERT_ID(), ON DUPLICATE KEY UPDATE, LOAD DATA INFILE, LOCK TABLES / UNLOCK TABLES, FIND_IN_SET(), CHARACTER SET / COLLATION, SELECT ... FOR UPDATE (MySQL).