What is a data manipulation language? What are the types of data manipulation languages and what are the differences between them?

Data Manipulation Language

A data manipulation language is a language that allows the user to read, add, and delete previously stored data from a database. Functions in the Data Manipulation Language or DML can be used directly by application programs in the data management system. E.g.- Employee Name entity set or file has attributes Employee Name, Employee ID Number, Last Name, Address etc. Now if you need to see the name and surname of the employees from among them, then it is possible to see it with data manipulation language.

There are two types of data manipulation languages ​​namely--

 (i) Procedural

(ii) Non-Procedural.

Description of Data Manipulation Language Statements:

(i) Select statement SQL language Select statement is used for data retrieval. It can also be used to select data from multiple relations.

Syntax of SELECT statement-

SELECT [district]<target list> from <relation list> [ where <predicate >]

(ii) UPDATE statement UPDATE statement is used to modify one or more records from a relation or table.

UPDATE Statement Syntax –

UPDATE <relation> set < target - value list. [where <predicate>]

(iii) DELETE Statement This statement is used to delete one or more records from a relation or table.

DELETE statement syntax

DELETE <relation> [where <predicate>]

(iv) INSERT Statement This statement is used to add new records to a table

INSERT statement syntax --

INSERT INTO <relation> Values ​​(<value list>)

 • Procedural and non-procedural data manipulation languages:

Procedural DML - The user has to tell the data to work on and where that data is located. This is called Procedural DML or Data Manipulation Language. Procedural DML is a difficult language to learn and apply.

Non-Procedural DML - The user is only directed to the data, without needing to tell the location of the data. This is called non-procedural DML. It is easy to learn and apply the language.

Difference between procedural and non-procedural DML

Procedural Data Manipulation Language:

(i) The user has to tell the user what data to work on and where that data is located. DML says. It is also called Procedural Data Manipulation Language.

(ii) Its language is difficult to learn and apply.

(iii) The user needs to identify how the data will be accessed.

Non-procedural data manipulation language:

(i) The user is only guided, not required to tell the location of the data.

(ii) Its language is easy to learn and apply.

(iii) does not require the user to identify how the data may be obtained;