Is NoSQL 100% ACID 100% of the time? -



Is NoSQL 100% ACID 100% of the time? -

quoting: http://gigaom.com/cloud/facebook-trapped-in-mysql-fate-worse-than-death/

there have been various attempts overcome sql’s performance , scalability problems, including buzzworthy nosql motion burst onto scene couple of years ago. however, discovered while nosql might faster , scale better, did @ expense of acid consistency.

wait - reading wrongly?

does mean if utilize nosql, can expect transactions corrupted (albeit daresay @ low percentage)?

it's true , yet bit false. it's not corruption it's seeing different during (limited) period.

the real thing here cap theorem states can take 2 of next three:

consistency (all nodes see same info @ same time) availability (a guarantee every request receives response whether successful or failed) partition tolerance (the scheme continues operate despite arbitrary message loss)

the traditional sql systems take drop "partition tolerance" many (not all) of nosql systems take drop "consistency".

more precise: drop "strong consistency" , select more relaxed consistency model "eventual consistency".

so info consistent when viewed various perspectives, not right away.

nosql

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