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From:Mats Kindahl Date:May 11 2010 8:55am
Subject:Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replication
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On 05/11/2010 10:30 AM, Sergei Golubchik wrote:
> Hi, Mats!
>
> On May 11, Mats Kindahl wrote:
>   
>> Hi Zardosht,
>>
>> The flag HA_EXTRA_WRITE_CAN_REPLACE only is set on the slave for Write
>> rows when --slave-exec-mode is IDEMPOTENT *or when the NDB Cluster
>> engine is used*. In other words, the NDB engine is hardcoded to always
>> use IDEMPOTENT.
>>     
> Which is, arguably, a bug. The flag is not HA_EXTRA_IS_NDB_CLUSTER,
> other engines may take use of it too.
>   

Agree on that, but we have no support for allowing the engine to give
this information right now.

Note that the HA_EXTRA flags are means for the server to communicate
with the engine, not the other way around. This flag says "I'm executing
a replace right now, so you can optimize for that if you like."

Best wishes,
Mats Kindahl

>  
> Regards,
> Sergei
>   


-- 
Mats Kindahl
Senior Software Engineer
Database Technology Group
Sun Microsystems

Thread
HA_EXTRA_WRITE_CAN_REPLACE and row based replicationZardosht Kasheff10 May
  • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationMats Kindahl11 May
    • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationSergei Golubchik11 May
      • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationMats Kindahl11 May
        • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationZardosht Kasheff11 May
          • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationZardosht Kasheff11 May
          • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationMats Kindahl11 May
            • Re: HA_EXTRA_WRITE_CAN_REPLACE and row based replicationZardosht Kasheff11 May