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Nulls Confusing but necessaey...

by Alejandro

Hello All

The article is quite clear and to the point.

Still i just want to remark the central point, which might not be clear from the article: NULLS are confusing, but necessary. We just need to learn to use them, because YES -> they have a use.

Some operations CANT be performed with out NULLS.

A simple average of numbers will not return the correct average if you simple put zeros in where you dont have the correct value. By using nulls the average will only run over the valid numbers and return a correct average, or as correct as possible given the number of samples.

With out nulls, operations like that cant be performed.

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