DCLGEN is stands for DeCLarations GENErator. It is used to create the host language copy books for the table definitions. It also creates the DECLARE table.

In the context of IBM Db2, DCLGEN stands for “Data Control Language Generator.” It is a utility used to generate Data Control Language (DCL) statements for embedding in application programs written in languages such as COBOL or PL/I.

DCL statements are used to define the structure and access control for database objects, such as tables and views. DCLGEN helps in the generation of these statements based on the structure of the database objects, making it easier for developers to include access control statements in their application programs.

In summary, DCLGEN in DB2 simplifies the process of embedding Data Control Language statements in application programs, facilitating the management of access control for database objects within those programs.