![]() The initial overviews are intentionally brief. Types in each category, and a summary of the data type storage (character and byte) types, spatial types, and theĪn overview and more detailed description of the properties of the ![]() Several categories: numeric types, date and time types, string MEDIUMINT, BIGINT 11.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC 11.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE 11.1.5 Bit-Value Type - BIT 11.1.6 Numeric Type Attributes 11.1.7 Out-of-Range and Overflow Handling 11.2 Date and Time Data Types 11.2.1 Date and Time Data Type Syntax 11.2.2 The DATE, DATETIME, and TIMESTAMP Types 11.2.3 The TIME Type 11.2.4 The YEAR Type 11.2.5 Automatic Initialization and Updating for TIMESTAMP and DATETIME 11.2.6 Fractional Seconds in Time Values 11.2.7 What Calendar Is Used By MySQL? 11.2.8 Conversion Between Date and Time Types 11.2.9 2-Digit Years in Dates 11.3 String Data Types 11.3.1 String Data Type Syntax 11.3.2 The CHAR and VARCHAR Types 11.3.3 The BINARY and VARBINARY Types 11.3.4 The BLOB and TEXT Types 11.3.5 The ENUM Type 11.3.6 The SET Type 11.4 Spatial Data Types 11.4.1 Spatial Data Types 11.4.2 The OpenGIS Geometry Model 11.4.3 Supported Spatial Data Formats 11.4.4 Geometry Well-Formedness and Validity 11.4.5 Spatial Reference System Support 11.4.6 Creating Spatial Columns 11.4.7 Populating Spatial Columns 11.4.8 Fetching Spatial Data 11.4.9 Optimizing Spatial Analysis 11.4.10 Creating Spatial Indexes 11.4.11 Using Spatial Indexes 11.5 The JSON Data Type 11.6 Data Type Default Values 11.7 Data Type Storage Requirements 11.8 Choosing the Right Type for a Column 11.9 Using Data Types from Other Database Engines ![]() Through the introduction in this article, it is believed that readers now have a deeper understanding of the ENUM data type, and hopefully this can help everyone better design and manage MySQL databases.Table of Contents 11.1 Numeric Data Types 11.1.1 Numeric Data Type Syntax 11.1.2 Integer Types (Exact Value) - INTEGER, INT, SMALLINT, TINYINT, In conclusion, based on the different business scenarios and data requirements, we can choose different data types to define columns in MySQL. However, there are some limitations with ENUM type data, such as the inability to expand the list of options. An ENUM is a string object with a value chosen from a list of allowed values that are enumerated explicitly in the column specification at table creation. It not only helps to prevent input errors, but also improves the readability and maintainability of data. When we need to define a column that can only take a specific set of values, ENUM is a great choice. What is the advantage of using an ENUM A. Especially if you add the values after the table is already in use, because you have to alter the table structure to accommodate. I would say as you add more values though, any advantage starts to swing away from ENUM. enum defines a set of values to be assigned to the column a better example is ALTER TABLE tablename ADD columnname enum ( value1, value2 .,valuen) can't define also CHAR (1) because ENUM os a type mysql internally use int to represents ENUM it uses the ordinal positions of the value in the definition so value1 is eq to 0 value2. When we need to define a column that can only take a specific set of values, ENUM is a great choice. ENUM does take up some metadata for the string value associated with it though. This greatly simplifies the restriction and validation of column values, and also facilitates data handling and management. ![]() In MySQL, the ENUM data type is a useful data type that allows us to define a set of optional values and ensures that only one of these values can be stored in a column. ![]()
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