問題文
A developer writes NULLIF and passes the literal null as the first argument and a column as the second. The intent is to return a null whenever the column holds a null. What is the outcome of that statement?
選択肢
- The statement is rejected and the first argument has to be written as something other than a literal null value.
- The statement runs and the result is a null for every row that the query returns from the table.
- The statement runs and the second argument is returned for the rows where the first one is a null.
- The statement runs and the first argument is compared with the second one in the usual way for this function.