Mongodb,redis,hbase are NoSQL databases, what are their biggest differences and different positioning?

When SQL doesn't meet your needs or SQL is not a must or the best choice, it's time to consider this kind of nosql.

When your memory is larger than your data, the schema is not too sure, MongoDB here quietly waiting for my SQL job to see the busy, do not change the design mode, cool in front of pain in the back;

When you are the only pursuit of speed, but also to memcached too simple discord, just memory is more than the data, Redis Qiao sang and stood there;

Big, big, too big, I said the data, our 128GB memory dual CPU25TB storage only enough for a week, estimated there is no choice syndrome, HBase became the only or only two choice.
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So, not strictly speaking, redis positioning in the "fast", hbase positioning in the "big", mongodb positioning in the "flexible."

The advantage of NoSQL is just SQL's Achilles heel, and its weakness is just the killer of SQL.
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The biggest difference is that, in general use, MongoDB can be used as a simple scenario, but the performance of a high number of MySQL, Redis basically only used to do the cache, HBase for offline computing

Harry Zhu
Links: https://www.zhihu.com/question/30219620/answer/48322171
Source: Know
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Mongodb,redis,hbase are NoSQL databases, what are their biggest differences and different positioning?