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Data Manipulation Language (DML)

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Introduction Of DML

  • It is defined as the language that provides set of operations to support the basic data manipulation operations on the data held in the database.
  • It allows user to insert, update, delete, and retrieve data from the database. The data manipulation is :
    • The retrieval of information stored in database 
    • The insertion of new information into the database.
    • The deletion of information from the database
    • The modification of information stored in database
  • The part of the DML that involves the data retrieval is called a query language. Following are the commands used in DML
  1. SELECT : retrieves data from database
  2.  INSERT : insert data into table
  3. UPDATE : update existing data with a table 
  4. DELETE : delete all records from a database table
  5. MERGE : UPSERT operation (insert or update)
  6. CALL : call a PL/SQL or java subprogram
  7. EXPLAINPLAN : interpretation of the data access path
  8. LOCKTABLE : concurrency table

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