• Selection: Retrieving data of all columns
  • Projection: Retrieving data from required columns
  • Joins: Retrieving data from multiple tables and creates new table
  • Set Operators: Union, Interset, except.

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    Data Retrieval Language is used to retrieve data from data base server.

     

    Capabilities of SQL Server SELECT statement

     

     

  • Though SELECT statement we can retrive data from Database and result stored in Table
  • A single select statement will support to retrieve data of 4096 columns from 255 tables.
  • SQL statements are not case sensitive
  • SELECTION and PROJECTION can be done through SELECT statement

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    State about STAR

     

     

  • * is termed as STAR
  • It pulls the all the columns of the data from Table
  • If the Query represents to multiple tables, * includes all the columns of every table

    • State the disadvantage of STAR

  • It returns all the columns of data in TABLE even though it is not required to user