Hi,
Is it okay to write to a table that is part of a merge table?
The documentation is not explicit on this as far as I understand
it.
Anyway, when I try this in a typical logging scenario that merge
tables are supposed to be useful for, I sometimes get incorrect
results.
My tables have these fields (and more):
id: integer
auth_time: integer
There are some indexes. One on the id field, one on the auth_time
field and some more indexes.
One process is INSERTing rows as fast as it can in one of the
underlying tables. The id field is incremented for each next row
(I set it explicitly even though it's an auto_increment field).
The auth_time field is a UNIX timestamp which is a non-decreasing
value.
In the mysql command-line client I do this:
select count(*), max(id), from_unixtime(max(auth_time)) from
authentication;
Most of the time the results are plausible, but sometimes one
or more of the result fields are 0 [for count(*)] or NULL.
When I do this:
explain select count(*), max(id), from_unixtime(max(auth_time))
from authentication;
Most of the time I get a comment 'Select tables optimized away'
but sometimes I get 'No matching min/max row' which seems to
indicate an empty table (or some error condition).
This makes me wonder if it's 'allowed' to update the tables
that make up a merge table.
MySQL is running on Solaris 7 for SPARC.
Any help on this will be greatly appreciated.
Fred.
--
Fred van Engen XO Communications B.V.
email: [EMAIL PROTECTED] Televisieweg 2
tel: +31 36 5462400 1322 AC Almere
fax: +31 36 5462424 The Netherlands
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