The role of the serial keyword in MySQL

SERIAL is an alias of BIGINT UNSIGNED not NULL auto_increment UNIQUE .

In the integer column definition,SERIAL DEFAULT VALUE is an alias of not NULL auto_increment UNIQUE .

Note: The above not NULL is not nullable, auto_increment is incremented, the specified starting value is 1 with the Auto_increment=1 statement, and the default is not specified to 1.

Uniqe is not meant to be duplicated, and the value cannot be duplicated with data that already exists.

The role of the serial keyword in MySQL