Code Inspection: Function signature

Reports signature issues for built-in functions.

The inspection will report a wrong number of arguments, invalid keywords, wrong data types, and other issues.

Example (MySQL):

CREATE TABLE foo (a INT, b INT, c INT)

SELECT IFNULL() FROM foo; -- error
SELECT IFNULL(a) FROM foo; -- error
SELECT IFNULL(a, b) FROM foo; -- OK
SELECT IFNULL(a, b, c) FROM foo; -- error

In MySQL, the IFNULL() function accepts strictly two arguments. So, only the SELECT IFNULL(a, b) FROM foo; query is correct.