Mysql enum6/2/2023 You can specify up to 65,535 values, but keep in mind that using too many values can negatively. , valueN) Here, columnname is the name of the column, and value1 through valueN are the allowed values for the column. MySQL maps these enumeration member to a numeric index where small=1, medium=2, large=3, and x-large=4 respectively. The syntax for creating an ENUM data type in MySQL is as follows: columnname ENUM(value1, value2, value3. The size column uses the ENUM data type and has small, medium, large, and x-large sizes. Here, we are going to create a table named " shirts" that contains three columns: id, name, and size. Let us understand how ENUM data type works in MySQL with the following illustration. ![]() An option also exists to automatically produce a CHECK constraint when the VARCHAR (so called non-native) variant is produced see the Enum.createconstraint flag. ENUM data type in My SQL includes the DEFAULT values as NULL or an empty string (''). The Enum type will make use of the backend’s native ENUM type if one is available otherwise, it uses a VARCHAR datatype. ENUM takes 1 byte (if under 255 values) or 2 bytes (up to maximum of 65,535 TinyInt takes 1 byte (maximum of 255 values) Boolean is a synonym for TinyInt So, on the surface, they're all the same. You can list up to 65535 values in an ENUM list. The DEFAULT expression does not allow to insert function. ) A string object that can have only one value, chosen from a list of possible values. ![]() In other words, if the INSERT statement does not provide a value for this column, then the default value will be inserted. NULL: It is a synonym for DEFAULT NULL, and its index value is always NULL.ĭEFAULT: When a value is not specified in the column, the ENUM data type inserts the default value. In MySQL one can create an enum as such: USE WorldofWarcraft CREATE TABLE users ( ID INT NOT NULL IDENTITY(1,1) PRIMARY KEY, username varchar(255), password varchar(255), mail varch. In MySQL, an ENUM is a string object whose value is chosen from a list of permitted values defined at the time of column creation. If we do not want to allow the NULL values, it is required to use the NOT NULL property while specifying the ENUM column. NOT NULL: By default, the ENUM data type is NULL. MySQL ENUM uses numeric indexes (1, 2, 3, ) to represents string values. The ENUM data type provides the following advantages: Compact data storage. MySQL allows us to define the ENUM data type with the following attributes: In MySQL, an ENUM is a string object whose value is chosen from a list of permitted values defined at the time of column creation. Here, we have to make sure that the enumeration values should always keep inside the quoted string literal. ![]() In the above syntax, we have defined only three ENUM values, but it can be increased according to our needs. It lets you specify a list of valid values when you set the data type (e.g. It allows us to limit the value chosen from a list of permitted values in the column specification at the time. Column2 ENUM ('value_1','value_2','value_3'), The ENUM data type in MySQL is a string object.
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