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From:Lucio Chiappetti Date:October 5 2011 9:22am
Subject:Re: How MyISAM handle auto_increment
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On Mon, 3 Oct 2011, Reindl Harald wrote:

>> I have questions regarding how MyISAM handles auto_increment clolumn?

> it is a table-property and you hould NOT touch it without godd reasons
> because it is named AUTO

I guess there are quite often good reasons to change it, which can be
done e.g. as

alter table north33b  auto_increment=200001;

I often generate an empty table with the same structure as another table 
with a statement like :

create table xxxx select * from yyyy limit 0;

(at this point I have to recreate also all indices etc. doing a show 
create table xxxx and show create table yyyy and alter table yyyy for 
anything which is missing)

The new table yyyy will have auto increment starting where xxxx ended. 
This is good (assuming xxxx will not grow any more) to preserve an 
UNIQUE sequence for all tables different for each table.

In case one wants yyyy to start at a "round number" one can just issue an 
alter table and reset auto_increment.

The same if one tests some procedure to populate a new table yyyy, then 
deletes everything, and wants that production population restarts from 1.

Lucio Chiappetti - INAF/IASF - via Bassini 15 - I-20133 Milano (Italy)
Citizens entrusted of public functions have the duty to accomplish them
with discipline and honour
                           [Art. 54 Constitution of the Italian Republic]
For more info :
How MyISAM handle auto_incrementAngela liu3 Oct
  • Re: How MyISAM handle auto_incrementReindl Harald3 Oct
    • Re: How MyISAM handle auto_incrementLucio Chiappetti5 Oct
  • Re: How MyISAM handle auto_incrementmos4 Oct
  • Re: How MyISAM handle auto_incrementAngela liu4 Oct
    • Re: How MyISAM handle auto_incrementmos4 Oct
RE: How MyISAM handle auto_incrementLucio Chiappetti6 Oct
  • RE: How MyISAM handle auto_incrementJerry Schwartz7 Oct