What does column mean in mysql

Column in MySQL is the storage unit for data in the table, and its characteristics include name, data type, constraints, default values ​​and indexes. They are used to organize, store and manage data, ensuring data integrity and consistency.

The meaning of Column in MySQL

Column (column) is a MySQL database table A structural unit of data storage that defines specific attributes and types of data in a table.

Key characteristics of Column:

• Name: The unique name that identifies the column.
• Data type: Specify the data type stored in the column (for example, integer, string, date).
• Constraints: Rules used to control the range and format of values ​​in a column (e.g., uniqueness, non-null).
• Default value: If no value is specified when inserting a row, the column will use this value.
• Index: Special data structure used to improve query speed.

The role of Column:

Column is used to organize and store data in the table. They provide the following functionality:

• Define and constrain data in tables.
• Allows sorting, filtering and retrieval of data.
• Ensure data integrity and consistency.

Notes on Column:

• MySQL tables can have up to 1024 columns.
• Column names cannot be repeated.
• The value in Column must conform to the specified data type.
• Column constraints should be carefully considered to ensure data validity and efficiency.

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