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Explain DML and DDL statements. Data definition language is used to define and manage all attributes and properties of a database.
Most DDL statements include following commands:
- CREATE
- ALTER
- DROP
Data Manipulation Language: Data manipulation language is used to select, insert, update, and delete data in the objects defined with DDL. Explain DML and DDL statements.DDL-Data Definition Language: DDL is the syntax of SQL for defining the way the database is organized physically. Database meta data is created by DDL of SQL. The tables, views, indexes, sequences, triggers, database users (by DBA) are well defined using DDL statement, CREATE. Modification for the metadata or schema is done by ALTER command and removing database objects is done by DROP command.
DML-Data Manipulation Language: DML statements, INSERT, DELETE, UPDATE AND SELECT … INTO are used for data manipulation, adding new rows, deleting unwanted rows and changing data in the rows. These are known as SQL-change statements. DML does not change the schema of database.
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