MySQL maps these enumeration member to a numeric index where small=1, medium=2, large=3, and x-large=4 respectively. The size column uses the ENUM data type and has small, medium, large, and x-large sizes. It uses numeric indexes (1, 2, 3) to represent string values. It is short for enumeration, which means that each column may have one of the specified possible values. It allows us to limit the value chosen from a list of permitted values in the column specification at the time of table creation. Here, we are going to create a table named " shirts" that contains three columns: id, name, and size. The ENUM data type in MySQL is a string object. Let us understand how ENUM data type works in MySQL with the following illustration. ENUM data type in My SQL includes the DEFAULT values as NULL or an empty string (''). The DEFAULT expression does not allow to insert function. 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. If we do not want to allow the NULL values, it is required to use the NOT NULL property while specifying the ENUM column. Im curious to know what the community thinks the proper use-case for an ENUM type vs. Your use of ENUM takes less storage space and is much faster than if you stored the actual strings since MySQL internally represents each choice as a number. NOT NULL: By default, the ENUM data type is NULL. MySQL allows us to define the ENUM data type with the following attributes: MySQL ENUM is a Key/String Value Pair Type. For this article, the MySQL version is 8.0.23, and the storage engine is InnoDB. Here, we have to make sure that the enumeration values should always keep inside the quoted string literal. After reading the following 12 key facts about MySQL ENUM, you can decide if it is good for your next database or table in MySQL. In the above syntax, we have defined only three ENUM values, but it can be increased according to our needs.
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