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Need some help on a simple query

  • February 26, 2005 at 12:59 am

    #162875

    Hello,

     

    I have six tables (COURSE, FACULTY, IS_QUALIFIED, IS_REGISTERED, SECTION, and STUDENT). What I need to do is create a query to display the course ID and course name for all courses with an ISM prefix. I have so far:

     

    SELECT*

    FROM COURSE, Course_ID, Course_Name

     

    My question is how do I create the last parameter that results in just courses with an ISM prefix?

     

    Thanks

     

  • February 26, 2005 at 6:16 am

    #544308

    If I got your problem correctly,

    u can use Like command

    i.e.

    Where Course_ID Liek 'ISM%'

    is this the answer you are looking for




    My Blog: http://dineshasanka.spaces.live.com/

  • February 26, 2005 at 10:02 am

    #544311

    Hi Dinesh,

     

    I have good news! This query works like a charm. I added DMC 4458 and ISM 4444 as new Course_ID’s and only ISM 4444 returned along with the other ISM’s. Thanks Dinesh for your help and input.

     

    SELECT Course_Name, Course_ID

    FROM COURSE

    WHERE (Course_ID LIKE 'ISM%')

    ORDER BY Course_Name DESC

    Dennis

  • March 1, 2005 at 8:41 am

    #544622

    hi there

    I think it would be quicker to use

    where left(course_id,3)='ISM'

    as this is a more exact match.  Wildcards tend to slow things down

    Ross

  • March 1, 2005 at 9:00 am

    #544627

    Thanks Ross,

    It works great.

    Dennis

  • March 1, 2005 at 9:49 am

    #544639

    Actually, LIKE 'something%' will perform better (only when you're looking from the beginning of the string - LIKE '%something%' will do a table scan).

    This is because LIKE can use an index, if an appropriate one exists. The other string functions use table scans.

    P

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