What are the different types of MYSQL commands?

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MySQL commands can be broadly categorized into several types based on their functionality. Here's an overview of the different types of MySQL commands:

Data Definition Language (DDL) Commands:

  1. CREATE: Used to create a new database or table.

    • CREATE DATABASE database_name;
    • CREATE TABLE table_name (column1 datatype, column2 datatype, ...);

  2. ALTER: Modifies an existing database or table.

    • ALTER TABLE table_name ADD column_name datatype;
    • ALTER TABLE table_name MODIFY column_name datatype;

  3. DROP: Deletes an existing database, table, or index.

    • DROP DATABASE database_name;
    • DROP TABLE table_name;

Data Manipulation Language (DML) Commands:

  1. SELECT: Retrieves data from one or more tables.

    • SELECT column1, column2 FROM table_name WHERE condition;

  2. INSERT: Adds new rows to a table.

    • INSERT INTO table_name (column1, column2) VALUES (value1, value2);

  3. UPDATE: Modifies existing records in a table.

    • UPDATE table_name SET column1 = value1 WHERE condition;

  4. DELETE: Removes rows from a table based on a condition.

    • DELETE FROM table_name WHERE condition;

Data Query Language (DQL) Commands:

  1. SELECT: Used to query the database and retrieve specific information.

Data Control Language (DCL) Commands:

  1. GRANT: Provides specific privileges to database objects.

    • GRANT privilege ON object TO user;

  2. REVOKE: Removes specific privileges from database objects.

    • REVOKE privilege ON object FROM user;

Transaction Control Commands:

  1. START TRANSACTION: Begins a new transaction.

    • START TRANSACTION;

  2. COMMIT: Saves the changes made during the current transaction.

    • COMMIT;

  3. ROLLBACK: Undoes the changes made during the current transaction.

    • ROLLBACK;

Data Administration Commands:

  1. SHOW: Displays information about databases, tables, columns, etc.

    • SHOW DATABASES;
    • SHOW TABLES;

  2. DESCRIBE or EXPLAIN: Shows the structure of a table.

    • DESCRIBE table_name;

These are some of the fundamental types of MySQL commands used for various database operations. Each type of command serves a specific purpose in managing and manipulating data within a MySQL database.

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