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Re: Problem creating a series of tables

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On 4/2/2015 6:44 PM, the pedantic troll Thomas 'Pointed Head' Lahn wrote:
> Thomas 'PointedEars' Lahn wrote:
> 
>> ,----
>> | mysql> create temporary table tmp (id int(10) primary key not null);
>> | Query OK, 0 rows affected (0.01 sec)
>> | 
>> | mysql> explain tmp;
>> | +-------+---------+------+-----+---------+-------+
>> | | Field | Type    | Null | Key | Default | Extra |
>> | +-------+---------+------+-----+---------+-------+
>> | | id    | int(10) | NO   | PRI | NULL    |       |
>> | +-------+---------+------+-----+---------+-------+
>> | 1 row in set (0.01 sec)
>> | 
>> | mysql> insert into tmp values (1);
>> | Query OK, 1 row affected (0.00 sec)
>> | 
>> | mysql> insert into tmp values (0);
>> | Query OK, 1 row affected (0.01 sec)
>> | 
>> | mysql> select * from tmp;
>> | +----+
>> | | id |
>> | +----+
>> | |  0 |
>> | |  1 |
>> | +----+
>> | 2 rows in set (0.00 sec)
>> `----
> 
> I realize that this is not a good test.  The order could still be arbitrary; 
> one run is insufficient to show the opposite.  But by the law of large 
> numbers, if the order of result records would be arbitrary, the record “1” 
> should occur at first position about 50 % of the time, and there should be 
> at least one occurrence of “1” at first position.  But:
> 
> $ mysql -u root -p$pass <<<'create database tmp; use tmp; create table tmp 
> (id int(10) primary key not null); insert into tmp values (1); insert into 
> tmp values (0);'
> 
> $ for i in $(seq 1 100); do mysql -u root -p$pass <<<'use tmp; select id 
> from tmp limit 1\G'; done | grep '^id: 0' | wc -l
> 100
> 
> $ for i in $(seq 1 1000); do mysql -u root -p$pass <<<'use tmp; select id 
> from tmp limit 1\G'; done | grep '^id: 1' | wc -l
> 0
> 
> $ for i in $(seq 1 10000); do mysql -u root -p$pass <<<'use tmp; select id 
> from tmp limit 1\G'; done | grep '^id: 1' | wc -l
> 0
> 
> $ for i in $(seq 1 100000); do mysql -u root -p$pass <<<'use tmp; select 
> id from tmp limit 1\G'; done | grep '^id: 1' | wc -l
> 0
> 
> You can repeat this with ever larger numbers; the results are consistent: 
> Never once is “1” at first position.  Because “0” always is, although that 
> record had been inserted *after* “1”.  Conclusion: The result records are 
> sorted by primary key.  Q.E.D.
> 

And what happens if you delete rows then insert more?

Your example works ONLY because you are inserting new rows into an empty
table - so obviously they are in order in the table.

But once you've DELETEd or UPDATEd rows, they do NOT have to be in any
specific order.

Your comments only serve to prove your ignorance.  You can copy and
paste code.  But you have no idea how it works.

-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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Problem creating a series of tables richard <noreply@example.com> - 2015-03-31 12:14 -0400
  Re: Problem creating a series of tables Paul Herber <paul@pherber.com> - 2015-03-31 19:09 +0100
    Re: Problem creating a series of tables richard <noreply@example.com> - 2015-03-31 14:30 -0400
  Re: Problem creating a series of tables Denis McMahon <denismfmcmahon@gmail.com> - 2015-03-31 19:40 +0000
    Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-03-31 16:19 -0400
      Re: Problem creating a series of tables Richard Yates <richard@yatesguitar.com> - 2015-03-31 18:07 -0700
        Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-03-31 21:23 -0400
      Re: Problem creating a series of tables Erwin Moller <erwinmollerusenet@xs4all.nl> - 2015-04-01 12:19 +0200
        Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-02 15:23 +0200
          Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-04-02 10:17 -0400
    Re: Problem creating a series of tables richard <noreply@example.com> - 2015-03-31 20:14 -0400
      Re: Problem creating a series of tables Doug Miller <doug_at_milmac_dot_com@example.com> - 2015-04-01 02:44 +0000
        Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-03-31 23:06 -0400
          Re: Problem creating a series of tables richard <noreply@example.com> - 2015-04-01 00:09 -0400
            Re: Problem creating a series of tables Doug Miller <doug_at_milmac_dot_com@example.com> - 2015-04-01 20:37 +0000
              Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-04-01 17:08 -0400
    Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-02 14:50 +0200
      Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-04-02 10:20 -0400
        Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-02 22:32 +0200
          Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-03 00:44 +0200
            Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-04-02 19:22 -0400
            Re: Problem creating a series of tables Jerry Stuckle <jstucklex@attglobal.net> - 2015-04-02 19:24 -0400
            Re: Problem creating a series of tables "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-04-03 01:46 +0200
              Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-03 20:45 +0200
          Re: Problem creating a series of tables Richard Yates <richard@yatesguitar.com> - 2015-04-02 15:59 -0700
            Re: Problem creating a series of tables Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-04-03 01:10 +0200
              Re: Problem creating a series of tables Richard Yates <richard@yatesguitar.com> - 2015-04-02 18:44 -0700

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