What does the term “Tuple” Mean in Relational Databases?

Question

Please explain what is meant by tuples in sql?Thanks..

Answer 1

As I understand it a table has a set K of keys and a typing function T with domain K. A row, or "tuple", of the table is a function r with domain K such that r(k) is an element of T(k) for each key k. So the terminology is misleading in that a "tuple" is really more like an associative array.