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MYSQL Interview question..



MySQL is an open source relational database management system RDBMS based on Structured Query Language SQL

MySQL runs on virtually all platforms, including Linux, Unix, Windows. Although it can be used in a wide range of applications, MySQL is most often associated with web-based applications and online publishing and is an important component of an open source enterprise.


1) What is SQL?

  • SQL stands for Structured Query Language.
  • SQL was initially developed at IBM in 1970s.
  • SQL is the standard language to communicate with relational database management systems like Oracle, MS Access, MS SQL Server, MySQL, DB2 etc.
  • It is used to connect the objects with the database.

2)what is the Purpose of SQL?

•SQL is used to Create New Databases.
• SQL is used to Create New Tables in a Database.
• SQL is used to Insert, update, Delete records in a Database.
• SQL is used to Retrieve data from a Database.
• SQL is used to execute queries against a Database.
• SQL can set permissions on tables, procedures and views.
• SQL is used to Create stored procedures in a Database.
• SQL is used to Create views in a Database.

3) Who should learn SQL?

Database Developers

• Design and deploy Database table structures, forms, reports and queries etc.

4)what is the subset of SQL?

DCL: Data Control Language.

DDL: Data Definition Language.

DML: Data Manipulation Language.

 5) What is DDL?

  • Create
  • Alter
  • Drop
  • Truncate
  • Rename

6)What is DCL?

  • Grant: It will access the database objects to the user
  • Revoke: It will remove user access rights database access 
  • Deny: It will deny the user Permission.

7)What is DML?

      *Select
      *Insert
      *Delete
      *Update   

8)what are the Joins in MySQL?       

  • Inner Join
  • Outer Join
  • Left Join
  • Right Join
  • Full Join

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