I recently wrote about NVL2. A function much like NVL2 is coalesce.
Coalesce is of the format COALESCE(expr1, expr2, exprN...)
Coalesce returns the first non-null expression in the expression list.
Coalesce is different from most SQL functions in that it allows a varying number of expressions.
Coalesce is basically a big IF statement:
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