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Writing data does not yield feedback

If the INSERT statement worked, you should not see any response in the shell whatsoever; it should simply provide you with a new command prompt. This is not simply a quirk of the CQL shell, but a fundamental fact about writing data in Cassandra; writing data does not normally result in any information about the operation from the database, other than an error message if the write failed. Most client libraries will return a null value, or the equivalent in the language in question, when you perform a successful write query.

This may come as a surprise if you're used to working with an SQL database, which will typically give you a detailed feedback when you write data, such as returning the primary key of the new row or simply telling you how many rows were affected by the operation.

We'll see some exceptions to this rule when we explore lightweight transactions in Chapter 7, Expanding Your Data Model.

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