1SELECT IFNULL(Price, 0) FROM Products;
2SELECT COALESCE(Price, 0) FROM Products;
3-- Oracle (extra):
4SELECT NVL(Price, 0) FROM Products;
1--See records where specific column is NULL
2SELECT * from table1 WHERE column1 ISNULL
3
4--Update all the NULL values in the selected column
5UPDATE table1 SET column1 = replace_value WHERE column1 ISNULL