POSITION (string_expression_1 IN string_expression_2)
Teradata Manuals says the following.
POSITION is expected to return a value according to the following rules.
* If string_expression_1 has length zero, then the result is one.
* If string_expression_1 is a substring within string_expression_2, the result is one greater than the number of characters (or bits, depending on the string) in string_expression_2 that precede the first occurrence.
* For all other events, the result is zero. Regardless of the character data type, the value for POSITION represents the position of the logical character, not its byte position.