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Transtact-SQL Overview

Transtact-SQL is the development of the SQL language published by the International Organization for Standardization (ISO) and American National Standards Institute (ANSI). Transtact-SQL, is needed in the SQL server. Every application that communicates with SQL Server will send Transtact-SQL command to the server.

Transtact-SQL command is a set of programs that run on ata data objects in the database. SQL Server has three types of Transtact-SQL, the Data Definition Language, Data Control Language, and Manipulation Language.

Data Definition Language (DDL)

Data Definition Language (DDL) is part of a database management system, used to define the data and manage all the attributes and properties from a database. With the DDL you can specify the column definitions, key columns, files location, and storage strategy.

General form of DDL statements:
CREATE object_name
ALTER object_name
DROP object_name

Data Control Language (DCL)

DCL is used to adjust the controls on database objects. Commands can be used is the GRANT and REVOKE.

GRANT command is used to give rights to user to access a database. REVOKE command is used to dispose of the rights granted to the user

Manipulation Language (DML)

DML is used to display, add, modify, and delete data in the objects defined by DDL. DDL Commands are SELECT, INSERT, UPDATE, DELETE.

SELECT command will search the records from the database
INSERT command is used to add new records on a table or view.
UPDATE command is used to change the data in a table.
DELETE command is used to remove data in a table.

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