Data Definition Language (DDL)

 

DDL statements in SQL are expressions built mainly around the following commands:

 

Statements Usage
CREATE Used to create new tables, fields, views and indexes.
DROP and DELETE Used to delete tables and indexes from the database.
ALTER Used to modify tables by adding fields or changing field definitions
GRANT and REVOKE Use to handle privileges

 

Almost all data definition language statements are data source specific. For example, the CREATE TABLE statement does not use the standard ODBC data types. Instead, it uses data source-specific data types. Because of this, the syntax is not provided for the data definition language statements supported by ODBC. Therefore, they will not be discussed in this manual.