slave lag should be easy to do with a simple bash script. i.e. -
desired_delay=3600 # one hour lag
while sleep 60
do
behind=`mysql -u root --password=foobar -e "show slave status\G" |
grep 'Seconds_Behind_Master:' | awk '{ printf "%s\n", $2 }'`
if [ $behind < $desired_delay ]; then
mysql -u root --password=foobar -e "slave stop"
holdtime=`expr $desired_delay - $behind`
if [ $holdtime -gt 0]; then
mysql -u root --password=foobar -e "slave stop"
fi
else
mysql -u root --password=foobar -e "slave start"
fi
done
Not pretty, but should do the job with more sanity checks, with the
caveat that sometimes Seconds_Behind_Master can return some interesting
values....
Howard Hart
Ooma, Inc.
ewen fortune wrote:
> Hi Shain,
>
> If you are using InnoDB its possible to patch to allow this functionality.
>
> Percona are in the early stages of developing a patch specifically to
> allow flashback type access to previous table states.
>
> https://bugs.launchpad.net/percona-patches/+bug/301925
>
> If you wanted to go down the slave lag road, Maatkit has a tool for doing that.
>
> http://www.maatkit.org/doc/mk-slave-delay.html
>
> Cheers,
>
> Ewen
>
> On Tue, Nov 25, 2008 at 6:57 PM, Shain Miley <smiley@stripped> wrote:
>
>> Hello,
>> We are planning on trying to do an Oracle to MySQL migration in the near
>> future. The issue of a Mysql equivalent to Oracle's flashback was being
>> discussed. After some digging it appears that there is no such feature in
>> Mysql. One thought that I had was to do some intentional replication lag
>> (say 12 to 24 hours)...that way if we needed to revert back we would have
>> the option of doing so.
>>
>> Does anyone:
>>
>> a: know how to setup a replication to intentionally lag?
>>
>> b: know of a better way of engineering a flashback equivalent for Mysql?
>>
>> Thanks in advance,
>>
>> Shain
>>
>> --
>> MySQL General Mailing List
>> For list archives: http://lists.mysql.com/mysql
>> To unsubscribe: http://lists.mysql.com/mysql?unsub=1
>>
>>
>>
>
>
