mongodb - Oracle (RAC) vs NoSQL -

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i curious if did benchmarks accessing of data in nosql databases vs oracle (particularly talking oracle rac)? project requires work @ least 10mil+ of records, search among them (but not necessary have real time), read important speed, , it's important guarantee ha , reliability (can't lose records!!!) can see myself how cassandra/mongodb might better fit (because key value storage provide faster reads sql when go on 10mil records), find difficult articulate of them nicely. links? suggestions? bullet points? thanks!

10 million records. assume 250 bytes per record. 2.5 gb of data, within capacity of basic desktop / laptop pc. data volumes insignificant (unless each record sized in mb, such picture or audio).

what need talk transaction volumes (separated read , write) , consider ha. read-only ha easy relative "read-write ha". can trivial replicate read-only data set off multiple servers @ different geographic locations , distribute query workload on them.

it's harder scale out update heavy workload, why hear systems going meltdown when tickets big concert released. quite there's fixed number of seats , can't have ten duplicated systems each selling think available. there has single source of truth, means bottleneck (and potentially single point of failure).

on ha aspect, rac shared storage technology means rac nodes in close proximity. can make them vulnerable localized events such building fire or telecoms breakdown. data guard oracle technology relates off-site replication , failover.


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