Best Way to check that table is empty - Page 2
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Thread: Best Way to check that table is empty

  1. #11
    Join Date
    Jan 2004
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    I can't help but notice that line 14 appears to have a small but significant cost. I wonder what happens on that line?

  2. #12
    Join Date
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    Quote Originally Posted by padders
    I can't help but notice that line 14 appears to have a small but significant cost. I wonder what happens on that line?
    That small but insignificant cost is the fetch into the explicit cursor.
    But for most systems all three methods are equally valid, IMHO.
    this space intentionally left blank

  3. #13
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    ATLANTA, GA, USA
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    Thanks

    Line 46 (select) is faster than line 30 (select count(*)).
    This is what I expected.

    Tamil

  4. #14
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    I'd still maintain that, in most cases, select count(*) is more efficient in human terms - less coding and somewhat easier to understand when you return to it two years hence - unless you spend half a screen explaining why you need that cursor!
    "The power of instruction is seldom of much efficacy except in those happy dispositions where it is almost superfluous" - Gibbon, quoted by R.P.Feynman

  5. #15
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    The results prove that they are equal.

    Code:
    use_explicit_cursor returned TRUE!!!
    use_explicit_cursor Time (seconds) 0
    use_select_into returned TRUE!!!
    use_select_into_1 Time (seconds) 0
    use_select_into returned TRUE!!!
    use_select_into_2 Time (seconds) 0
    
    PL/SQL procedure successfully completed.
    
    Elapsed: 00:00:00.00
    this space intentionally left blank

  6. #16
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