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NoSQL and Oracle, Sex and Marriage

At last week’s Dallas Oracle Users Group meeting, an Oracle DBA asked me, “With all the new database alternatives out there today, like all these open source NoSQL databases, would you recommend for us to learn some of those?”

I told him I had a theory about how these got so popular and that I wanted to share that before I answered his question.

My theory is this. Developers perceive Oracle as being too costly, time-consuming, and complex:

Teradata CAP定理

参考:Teradata RDBMS SQL Reference - Volume 2 Statement and Transaction Processing

Atomicity A transaction either occurs or it does not. No matter how many component SQL operations are specified within the boundaries of a transaction, they must all complete successfully and commit or they must all fail and rollback. There are no partial transactions.
Consistency A transaction transforms one consistent database state into another. Intermediate inconsistencies in the database are not permitted.
Isolation The operations of any transaction are concealed from all other transactions until that transaction commits.
Durability Once a commit has been made, the new consistent state of the database survives even if the underlying system crashes.