Question

What MySQL returns if the list of strings, provided as argument in FIELD() function, are NULL?

Answer 1

Answer:

If the search string is not found, it returns a 0(zero). If the search string is NULL, the return value is 0 because NULL fails equality comparison with any value. FIELD() is the complement of ELT().MySQL FIELD() returns the index position of the searching string from a list of strings.

Answer 2

MySQL FIELD() returns the index position of the searching string from a list of strings. ... If the search string is NULL, the return value is 0 because NULL fails equality comparison with any value. FIELD() is the complement of ELT(). When all arguments of the FIELD() are strings, they are compared as strings.