Question: can we use nvl in update query?
Answer: UPDATE test SET test1 = NVL(test1, 'hello'), test2 = NVL(test2, 'world') WHERE test2 IS NULL OR test1 IS NULL; Though it may fire your update triggers even for the rows that are effectively unchanged. COALESCE() works similarly to NVL() in this circumstance -- returning the first non-null value.