Question: SqlNullValueException: Data is Null. This method or property cannot be called on Null values. Answer: The `SqlNullValueException` is a type of exception that is thrown when an application attempts to perform an operation on a `NULL` value in a SQL database. In other words, this exception is thrown when a method or property is called on a `NULL` value in a SQL database and the method or property cannot be applied to a `NULL` value. If you are working in Entity Framework, make sure that the Column or Property has default values before calling the Database. To resolve this issue, you will need to check if the value you are trying to use is `NULL` before calling any methods or properties on it. You can use the `IS NULL` operator to check if a value is `NULL`. For example: SELECT TOP 1 1 FROM myTable WHERE myColumn IS NULL; If you are working with a `NULL` value in code, you can use a conditional statement to check for `NULL` values before calling methods or properties on the value. For example: if (myValue != null) { // Call method or property on myValue } else { // Handle NULL value } By checking for `NULL` values before calling methods or properties on them, you can avoid the `SqlNullValueException` and ensure that your application behaves as expected.