How to write mysql check constraints

MySQL method for writing check constraints: 1. Use the ENUM data type. The ENUM data type allows us to define a fixed list of values when creating a table, and then limit the value of the column to a value in the list. For example, you can create a named is the gender column, and defines it as ENUM('male', 'female'), so that the value of this column can only be 'male' or 'female'; 2. Use a trigger. The trigger is a specific A database object that executes automatically when an event occurs. Triggers can be used to implement more complex check constraints.

112

mysql

How to write mysql check constraints

How to write check constraints in mysql

Sep 25, 2023 pm 05:44 PM

mysql

How to write mysql check constraints

MySQL check constraints can be implemented through the [CREATE TABLE] or [ALTER TABLE] statement, which is defined according to the user's actual integrity requirements. The code is [CHECK ].

May 10, 2019 am 11:49 AM

mysql

What is the use of check constraints in mysql

The role of check constraints in mysql: used to specify the range of possible values for a column. Check constraints can be implemented through CREATE TABLE or ALTER TABLE statements, defined according to the user's actual integrity requirements.

May 07, 2019 pm 05:43 PM

mysql