Fix Oracle ISNULL Error: Use COALESCE

There is no direct ISNULL function in Oracle to check if a value is NULL. However, the COALESCE function can be used to achieve a similar effect. The COALESCE function takes multiple parameters and returns the first non-NULL value. If all parameters are NULL, it returns NULL.

For instance, if you want to check if a field is NULL, you can use the COALESCE function by passing the field as a parameter, and then compare the return value of the COALESCE function with NULL.

SELECT * FROM table_name WHERE COALESCE(column_name, NULL) IS NULL;

In the above statement, if the column_name field is NULL, the COALESCE function will return NULL. Comparing it with NULL will result in true, indicating that the field is NULL.

Hope this helps you!