Polymorphism in SQL part one – anyelement and anyarray
The term “polymorphism”, and its inflections, has various meanings in the context of programming languages in general. Roughly, it means “chameleon-like”. Of course, Wikipedia has something to say about it, here. PostgreSQL uses it with this meaning: “Parametric polymorphism: when one or more types are not specified by name but by… symbols that can represent any type”.
The term “variadic” has a universal meaning,
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