Page 320 - IT 402 v2.0 class 10
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Select

        A ‘SELECT’ statement retrieves zero or more rows from one or more database tables or database views. SELECT
        is the most useful DML command. The ‘SELECT’ statement has many optional clauses:
              specifies which rows to retrieve.

        O        specifies an order to return the rows.
        To e ecute  Select   ueries:
        Step 1:  Click on the ‘Queries’ option available on the left side under database section.

        Step 2:  Click ‘Create Query in SQL View’ in the ‘Tasks’ section. A window appears on the screen.
        Step 3:  Type the query in this window and execute it by pressing the F5 function key or by clicking the
                 ‘Execute’ icon in the window.

        To retrie e dis la  all t e data in a ta le:
            S nta   :  SE L E CT  *  F RO M  T AB L E NAM E ;
              am le :   To display all the data in the table:

                        SE L E CT  *  F RO M  ST U D E NT ;









              am le :  To get details of the list of students whose LASTNAME is Kumar:

                        SE L E CT  *  F RO M  ST U D E NT  W H E RE  L AST NAM E = ' K u mar ' ;







              am le :   To view the list of students in ascending order of MARKS:

                        SE L E CT  *  F RO M  ST U D E NT  O RD E R B Y  M ARK S ASC;

















        We can use aggregate functions to:

          Display the number of subjects or no of rows
          SE L E CT  CO U NT ( NO _ O F _ SU B )  F RO M  ST U D E NT ;
          Display Average of marks
          SE L E CT  AV G ( M ARK S)  F RO M  ST U D E NT ;




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