The Data Base Task Group (DBTG) was a working group founded in 1965 (initially named the List Processing Task Force and later renamed to DBTG in 1967) by the Cobol Committee, formerly Programming Language Committee, of the Conference of Data Systems Language (CODASYL

CODASYL

CODASYL is an acronym for "Conference on Data Systems Languages". This was a consortium formed in 1959 to guide the development of a standard programming language that could be used on many computers...

).

In April 1971, the DBTG published a report containing specifications of a Data Manipulation Language (DML) and a Data Definition Language (DDL) for standardization of network database model

Network model

The network model is a database model conceived as a flexible way of representing objects and their relationships. Its distinguishing feature is that the schema, viewed as a graph in which object types are nodes and relationship types are arcs, is not restricted to being a hierarchy or lattice.The...

. The first DBTG proposals had already been published in 1969. The specification was subsequently modified and developed in various committees and published by other reports in 1973 and 1978. The specification is often referred to as the DBTG database model or the CODASYL database model. As well as the data model, many basic concepts of database terminology were introduced by this group, notably the concepts of schema

Database schema

A database schema of a database system is its structure described in a formal language supported by the database management system and refers to the organization of data to create a blueprint of how a database will be constructed...

 and subschema.

Source

• Gunter Schlageter, Wolffried Stucky: Datenbanksysteme: Konzepte und Modelle, B. G. Teubner Stuttgart, 1983, ISBN 3-519-12339-8