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Archive for October 28th, 2013

5 Claims About SQL, Explained

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1. Is SQL is a declarative language?

First of all, let's define the terms.

A declarative language describes the result, not the process to achieve it. In a declarative language you tell "what do I need".

A procedural language describes control flow: exact steps the machine needs to perform in order to achieve this result. In a procedural language you tell "what do you do".

SQL, as it was originally designed, is a declarative language.

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For instance you need to know how many customers above 40 live in each city. You issue a query like:

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Written by Quassnoi

October 28th, 2013 at 11:00 pm

Posted in Miscellaneous