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What is DDL, DML and SQL |
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Answer» They are SQL commands DDL is abbreviation of Data Definition Language. It is used to create and modify the structure of database objects in database.CREATE – Creates objects in the databaseALTER – Alters objects of the databaseDROP – Deletes objects of the databaseTRUNCATE – Deletes all records from a table and resets table identity to initial value.DMLDML is abbreviation of Data Manipulation Language. It is used to retrieve, store, modify, delete, insert and update data in database.SELECT – Retrieves data from a tableINSERT – Inserts data into a tableUPDATE – Updates existing data into a tableDELETE – Deletes all records from a tableSQLStructured Query Language(SQL) as we all know is the database language by the use of which we can perform certain operations on the existing database and also we can use this language to create a database. SQL uses certain commands like Create, Drop, Insert etc. to carry out the required tasks.These SQL commands are mainly categorized into four categories as:\tDDL – Data Definition Language\tDQl – Data Query Language\tDML – Data Manipulation Language\tDCL – Data Control Language |
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