nosql - What are some real world implications of non-ACID database compliance? -

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specifically there risk data can lost? i'm looking @ running intensive transaction processing system critical nothing lost. there examples of nosql being used in mission critical applications such banking transaction processing?

without being flippant, absence of acid means no guarantees of atomicity, consistency, isolation, or durability.

without atomicity, no guarantee multiple actions must either succeed or fail so. instance, if transactions require debit 1 account , credit in 1 go, in absence of atomic transactions, either have roll own solution, or accept it's possible debit 1 account, without making corresponding credit.

without consistency, there's no guarantee "side effects" of transactions work - in relational databases, that's things firing of trigger, or cascading of foreign key relationship. so, if need kind of auto-incrementing unique identifier transaction, there's no guarantee one.

without isolation, there's no way guarantee 2 processes don't affect data @ same time. instance, 1 process might incrementing value of field, , second 1 might decrementing - wins?

without durability, hardware failure leave database in different state expect - instance, may believe change written data store, queued in internal memory buffer, , disappear thin air if there's power failure.

it's possible build solution on nosql works around absence of acid compliance, level of effort huge, , won't job guys write relational databases....


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