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From:gerald_clark Date:May 3 2004 6:35pm
Subject:Re: urban myth?
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It's also not in the order it was entered ( as suggested ).

Bob Ramsey wrote:

> Ah, but the ordering is not random.  As your example has it, the 
> results are in the order that the entries were inserted into the 
> table.  There is an explanation for the order of the returned data.
>
> bob
> At 12:55 PM 5/3/2004, Garth Webb wrote:
>
>> On Mon, 2004-05-03 at 10:39, Boyd E. Hemphill wrote:
>> > My boss says that if you do a select statement against a table the
>> > result set always comes back in the same order.  I say that this is a
>> > myth and that the result is random, except when some ordering is
>> > specified in the SQL statement.
>> >
>> > Who is right?  Is this behavior specified by ANSI or ISO?
>>
>> You are correct.  Ordering takes time.  Why choose a random column on
>> which to order the results and take additional time when the user didn't
>> ask for it.  Here's the proof:
>>
>> create temporary table foo (num int(10));
>> insert into foo values (1), (2), (3), (4), (5);
>> select * from foo;
>>
>> +------+
>> | num  |
>> +------+
>> |    1 |
>> |    2 |
>> |    3 |
>> |    4 |
>> |    5 |
>> +------+
>> 5 rows in set (0.00 sec)
>>
>> delete from foo where num = 3;
>> insert into foo values (6);
>> insert into foo values (3);
>> delete from foo where num = 6;
>> select * from foo;
>> +------+
>> | num  |
>> +------+
>> |    1 |
>> |    2 |
>> |    4 |
>> |    5 |
>> |    3 |
>> +------+
>> 5 rows in set (0.00 sec)
>>
>>
>> Garth
>>
>> -- 
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>
>
>
> ======================================================================
> Bob Ramsey          SYSTEMS ADMINISTRATION AND SYSTEMS PROGRAMMING III
> ph:  1(319)335-9956                              187 Boyd Law Building
> fax: 1(319)335-9019                  University of Iowa College of Law
> mailto:robert-ramsey@stripped                Iowa City, IA 52242-1113
> For Hardware and Software questions, call 5-9124
> ======================================================================
>
>


Thread
Create table results in (errno: 121)Tom Brown22 Apr
  • Re: Create table results in (errno: 121)Martijn Tonies22 Apr
  • Re: Create table results in (errno: 121)Tom Brown22 Apr
  • Re: Create table results in (errno: 121)Adam28 Apr
    • urban myth?Boyd E. Hemphill3 May
      • Re: urban myth?Peter J Milanese3 May
      • Re: urban myth?Daniel Clark3 May
      • Re: urban myth?Garth Webb3 May
        • Re: urban myth?Bob Ramsey3 May
          • Re: urban myth?Josh Trutwin3 May
          • Re: urban myth?Garth Webb3 May
          • Re: urban myth?Michael Stassen3 May
            • RE: urban myth?Boyd E. Hemphill3 May
              • Re: urban myth?Anders Karlsson3 May
              • Re: urban myth?Michael T. Babcock13 May
      • Re: urban myth?Josh Trutwin3 May
      • Re: urban myth?Jeremy Zawodny3 May
      • Re: urban myth?gerald_clark3 May
        • Re: urban myth?Peter J Milanese3 May
Re: Create table results in (errno: 121)beacker22 Apr
RE: urban myth?Mike Johnson3 May
Re: urban myth?Udikarni3 May