DBMS Languages

DBMS Languages

Data Definition Language(DDL): Used by the DBA and database designers to specify the conceptual schema of a database.

In many DBMSs, the DDL is also used to define internal and external schemas (views).

In some DBMSs, separate storage definition language(SDL) and view definition language(VDL) are used to define internal and external schemas.

Data Manipulation Language(DML): Used to specify database retrievals and updates.

DML commands (data sublanguage) can be embedded in a general-purpose programming language (host language), such as COBOL, C or an Assembly Language.

Alternatively, stand-alone DML commands can be applied directly (query language).

High Level or Non-procedural Languages : e.g., SQL, are set-oriented and specify what data to retrieve than how to retrieve. Also called declarative languages.

Low Level or Procedural Languages: record-at-a-time ;they specify how to retrieve data and include constructs such as looping.