Language In Database

Language In database: The most popular database access language is SQL. Relational Databases are required to have a database query language in the database of the same organization. Today most of the RDMSs use the SQL as database access language.

The sub-language is further divided into two major parts

  1. Data Definition Language
  2. Data Manipulation Language

Data Definition Language

The data definition language is used to define the structure of the database. The DBA and Database Designer use the database language to define the conceptual and internal schemas. Typically, the Data Definition Language (DDL) is used to define the conceptual schemas, whereas, Storage Definition Language is used to define the internal schemas. The mapping between the two schemas may be defined in either of these languages. In most DBMSs the DDL is used to define both conceptual and external schemas of the same data file of same organization. The DBMS has DDL compiler, which compiles the DDL statements and stores in DBMS catalog known as data dictionary.

Data Manipulation Language

Once the database is designed and database is populated with data, the data manipulation language (DML) is used to manipulate the database. In data manipulation, data is retrieved, inserted, updated and deleted to and from the database. It must be noted that DDL is not used for data manipulation.

The application programmer can insert the DML statements into the program written in general purpose language. Whenever, DML statements embedded in a general purpose programming language that language is called the Host Language and the DML is called Data Sub Language.