Note also; that reading at ONE there will be no read repair, since the 
coordinator does not know that another replica has stale data (remember at ONE, 
basically only one node is asked for the answer).

In practice for our use cases, we always write at LOCAL_QUORUM (failing the 
whole update if that doesn’t work - stale data is OK if >1 node is down), and 
we read at LOCAL_QUORUM, but (because stale data is better than no data), we 
will fall back per read request to LOCAL_ONE if we detect that there were 
insufficient nodes - this lets us cope with 2 down nodes in a 3 replica 
environment (or more if the nodes are not consecutive in the ring).

On Feb 20, 2014, at 11:21 PM, Drew Kutcharian <d...@venarc.com> wrote:

> Hi Guys,
> 
> I wanted to get some clarification on what happens when you write and read at 
> consistency level 1. Say I have a keyspace with replication factor of 3 and a 
> table which will contain write-once/read-only wide rows. If I write at 
> consistency level 1 and the write happens on node A and I read back at 
> consistency level 1 from another node other than A, say B, will C* return 
> “not found” or will it trigger a read-repair before responding? In addition, 
> what’s the best consistency level for reading/writing write-once/read-only 
> wide rows?
> 
> Thanks,
> 
> Drew
> 

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