Mastering the COALESCE Function in SQL

Although COALESCE , GREATEST , and LEAST are syntactically similar to functions, they are not ordinary functions, and thus cannot be used with explicit VARIADIC

The COALESCE scalar function takes two or more arguments and returns the first nonnull argument, starting from the left in the expression list Syntax

coalesce COALESCE Function Function returns the first non-missing value found in an array of columns The order of the columns listed in the function determines the

coalesce The coalesce function returns the first of the parameters that has a valid non-NULL representation Any number of parameters can be used