MySQL Interview Questions Part - 1

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MYSQL INTERVIEW QUESTIONS

 1) What is MySQL?

  • MySQL is a very popular open-source relational database management system.
  • To add, access, and process data stored in a database.

2) Difference between SQL and MySQL

SQLMYSQL
SQL is a query programming language that manages RDBMS.MySQL is a relational database management system that uses SQL.
SQL is primarily used to query and operate database systems.MySQL allows you to handle, store, modify and delete data and store data in an organized way.


3) Features of MySQL
  • Easy to use
  • Secure
  • Open source


4) Default port number of MySQL?

        The MySQL Server's default port is 3306

5) What is Primary key?
  • The PRIMARY KEY constraint uniquely identifies each record in a table.
  • Primary keys must contain UNIQUE values, and cannot contain NULL values.
  • A table can have only ONE primary key.


6) What is Foreign key?
  • It is like a child table. It refers only to primary key column values from another table. 
  • We can't insert any values directly in a child table without referring primary key table. 
  • We can't delete/update values directly in the primary key table if it refers to foreign key values.



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