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TECHIPEDIA (MYSQL)






                                        Hello Children, Today  we will learn about
                                        a  new tool  called  SQL.  SQL  stands  for
                                        Structured Query Language, and it is used
                                        to create and manage databases.



                 MySQL is an open-source RDBMS software which is available free of cost.  It can run on various
                 operating  systems,  including  Linux, Unix and Windows.  It uses  a query  language  called  SQL
                 (Structured Query Language). SQL is a language that is used for managing relational databases
                 and performing various operations on the data in the tables. It is used to store, retrieve, and
                 manipulate data in the form of tables.

                 TYPES OF SQL COMMANDS

                 SQL uses various commands to perform different operations on a database.

                 Data Definition Language (DDL)
                 DDL commands define the structure of the database. Common DDL statements include CREATE,

                 ALTER, TRUNCATE, RENAME, and DROP.

                 Data Manipulation Language (DML)

                 DML commands modify data within the database. Common DML statements include SELECT,
                 UPDATE, INSERT INTO, and DELETE.

                 Data Control Language (DCL)

                 DCL commands  grant and revoke  permissions  to  database  users. Common  DCL statements
                 include GRANT and REVOKE.

                 Transaction Control Language (TCL)

                 TCL commands manage database transactions, controlling how DML changes are committed or
                 rolled back. Common TCL statements include COMMIT, SAVEPOINT, and ROLLBACK.

                 DATA TYPES IN SQL

                 A data type specifies  the kind  of data  a column can store,  such as INTEGER,  VARCHAR,
                 or DATE. Each column in a table must be assigned a data type to ensure data consistency and
                 accuracy.










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