Basics of Statistics - Mathematics: Mean (Average), Median, Mode and Range

I want to calculate Mean (Average), Median, Mode and Range in Firebird 2.5 and 3.0.

I know that Firebird internal function for Mean (Average) is AVG(), but what are the internal functions for Median, Mode and Range in Firebird 2.5 and 3.0?

If there are not such functions, how can I calculate them using Firebird?

Thanks for all and any help.


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