NYCPHP Meetup

[Daniel Convissor]

Hi David:

On Mon, Feb 16, 2009 at 10:53:58AM -0500, David Krings wrote:
> Daniel Convissor wrote:
>> Hi David:
>>
>> On Mon, Feb 16, 2009 at 09:56:27AM -0500, David Krings wrote:
>>> Daniel Convissor wrote:
>>>> Uh, "have" is the wrong word there. :)  You don't need to drop a  
>>>> database before upgrading.  You leave your old tables in place and  
>>>> MySQL provides upgrade scripts that implement changes between 
>>>> server versions.
>>>
>>> So you are saying I could drop in the old system tables as well and 
>>> run the update application?
>>
>> Huh?
>
> Uhm, MySQL stores thing like user accounts and privileges in schemas...

Looking back at the exchange again I think I misunderstood your reply and 
you may have misunderstood what I was going for.

When I said "leave your old tables in place" I meant you should leave 
them there.  You don't need to move them.  When you install/upgrade 
MySQL, I assume it doesn't overwrite your existing tables.  My assumption 
may be influenced by the fact that I put the data directory in a 
particular location that is not where MySQL puts it by default.

When you said "drop in the old system tables" I missed the "in" so read 
it as "drop the old system tables."  Sorry.


> From what I read these system tables changed from the old to the new 
> version. 

Yes, there have been many changes over the years.  In the directory you 
install MySQL to there's a sub-directory called "scripts."  In there is a 
script called "mysql_fix_privilege_tables."  That script runs various 
ALTER/CREATE TABLE statements that bring you up to date.


> Also, changes are necessary for any other tables (the ones 
> created by users).

The data tables (almost) never need changing.  The only case that's 
needed changing was when ISAM format was dropped in favor of MyISAM.  For 
that, there's the "mysql_convert_table_format" script.

--Dan

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