I'm trying to figure out the best way to achieve single row modification
isolation for readers.
As an example, I have 2 rows (1,2) with 2 columns (a,b). If I modify both
rows,
I don't care if the user sees the write operations completed on 1 and not on 2
for a short time period (seconds). I also don't care if when reading row 1 the
user gets the new value, and then on a re-read gets the old value (within a few
seconds). Because of this, I have been planning on using a consistency level
of
one.
However, if I modify both columns A,B on a single row, I need both changes on
the row to be visible/invisible atomically. It doesn't matter if they both
become visible and then both invisible as the data propagates across nodes, but
a half-completed state on an initial read will basically be returning corrupt
data given my apps consistency requirements. My understanding from the FAQ
that
this single row multicolumn change provides no read isolation, so I will have
this problem. Is this correct? If so:
Question 1: Is there a way to get this type of isolation without using a
distributed locking mechanism like cages?
Question 2: Are there any plans to implement this type of isolation within
Cassandra?
Question 3: If I went with a distributed locking mechanism, what consistency
level would I need to use with Cassandra? Could I still get away with a
consistency level of one? It seems that if the initial write is done in a
non-isolated way, but if cross-node row synchronizations are done all or
nothing, I could still use one.
Question 4: Does anyone know of a good c# alternative to cages/zookeeper?
Thanks for any help with this!
