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Re: "Rewind" type of mechanisms?


 Thank you again!

Sam wrote:

Q: > > resync automatically --> Does it remove a possible (obsolete) rogue row?

Gordan Bobic wrote:

A: >  In asynchronous replication, yes it does.
Only to double check the same. To make sure we are discussing the same context. 

So, we are talking in the following context: in the "rewind" type of situation? (Rogue row.)
Rogue row is on old Master. Old Master has been switched to Standby mode. --> Rogue row gets rewinded automatically?

In other words,
With rogue row and rewind, I mean following situation:

Master -- Slave

1. Row is inserted to Master:
Master (new row) -- Slave

2. The row does not end up on Slave DB node. E.g. because of a sudden failover.

3. So:
Master (has rogue row)  --  Slave (rogue row does not end up on the Slave node)

4. The sudden failover happens in the middle.

5. The previous Master becomes New Slave:

New Slave (old Master, with the rogue row)  -- New Master (old Slave)

6. Now: "New Slave" has the rogue row. Such rogue row would need to be rewinded.

So, only to double check (repeating the same question). 
Q: MariaDB is able to rewind such automatically?

Is my understanding correct?

Async replication would be in use, with MaxScale in use.

Best Regards 

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