Bug #2369 REPLICATED DATA IN TIMESTAMP FIELD
Submitted: 13 Jan 2004 7:21 Modified: 13 Jan 2004 10:09
Reporter: Fabio Kaminski Email Updates:
Status: Not a Bug Impact on me:
None 
Category:MySQL Server: ISAM storage engine Severity:S2 (Serious)
Version:3.23.54a OS:Linux (Linux (i386))
Assigned to: Dean Ellis CPU Architecture:Any

[13 Jan 2004 7:21] Fabio Kaminski 
Description:
Synopses:
when a table has two timestamp fields, the second (in mysql internal order)timestamp type field, changes when the first timestamp field is updated.

example:
suppose that i have start_date(timestamp) and end_date(timestamp) in the same table.
if i send the following command:

"update table set end_date=CURRENT_TIMESTAMP"

the end_date and start_date now has the same value.

i try to drop the fields and add later in inverse order(end_date first,start_date last) and if i change end_date with update, it just chages itself , ok, that´s the expected behavior.
but if i change the start_date(that now is the second in order), the end_date also change.

How to repeat:
create two timestamp fields and try to send an update command ( i has just used the CURRENT_TIMESTAMP  and now(), to set this field´s) to the second filed in order, and it will change the first field in order of creation.
[13 Jan 2004 10:09] Dean Ellis 
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.mysql.com/documentation/ and the instructions on
how to report a bug at http://bugs.mysql.com/how-to-report.php

Additional info:

The behavior of multiple TIMESTAMP columns is documented in the manual:

http://www.mysql.com/doc/en/DATETIME.html