Data definition language - MySQL

DDL in MySQL is used to define and modify the structure of database objects such as tables, views, indexes, and constraints. It includes statements like CREATE, ALTER, and DROP to create, modify, or delete the database objects.

The CREATE statement in MySQL is used to create a new table. It specifies the table name, column names, data types, and any constraints or indexes associated with the table.

The ALTER VIEW statement in MySQL is used to modify the definition of a view, such as changing the columns displayed or the underlying SELECT statement.

The DROP statement in MySQL is used to delete a table, view, index, or other database objects. It permanently removes the specified object from the database.

The ADD COLUMN statement in MySQL is used to add a new column to an existing table. It specifies the column name, data type, and any constraints associated with the column.

The RENAME TABLE statement in MySQL is used to rename a table. It allows you to change the name of an existing table in the database.

The CREATE INDEX statement in MySQL is used to create a new index on one or more columns of a table. Indexes improve query performance by allowing faster data retrieval based on the indexed columns.

The PRIMARY KEY statement in MySQL is used to add a primary key constraint to a table. It specifies one or more columns that uniquely identify each record in the table.

The CREATE VIEW statement in MySQL is used to create a new view. A view is a virtual table derived from one or more tables or other views, which can be queried like a regular table.

The DROP COLUMN statement in MySQL is used to remove a column from an existing table. It permanently deletes the specified column and its associated data from the table.

The MODIFY COLUMN statement in MySQL is used to modify the data type of an existing column in a table. It allows you to change the data type while preserving the column's name and other attributes.

The CREATE DATABASE statement in MySQL is used to create a new database. It specifies the name of the database and optional character set and collation settings.

The FOREIGN KEY statement in MySQL is used to add a foreign key constraint to a table. It establishes a relationship between two tables based on a column or set of columns.

The TRUNCATE TABLE statement in MySQL is used to delete all data from a table while preserving the table structure. It is a faster alternative to the DELETE statement for removing all rows from a table.

The CHANGE COLUMN statement in MySQL is used to change the name of an existing column in a table. It allows you to specify the current column name and the new column name.

The DROP PRIMARY KEY statement in MySQL is used to remove the primary key constraint from a table. It allows you to remove the primary key designation from one or more columns.

The UNIQUE KEY statement in MySQL is used to add a unique constraint to a column in a table. It ensures that the values in the column are unique across all rows.

The CREATE INDEX statement in MySQL is used to create a new index on one or more columns of a table. It improves query performance by allowing faster data retrieval based on the indexed columns.

The ADD CHECK statement in MySQL is used to add a check constraint to a column in a table. It allows you to define a condition that must be satisfied by the values in the column.

The DROP VIEW statement in MySQL is used to delete a view. It permanently removes the specified view from the database.