Possible null reference assignment.

Possible null reference return.

Unboxing a possibly null value.

Non-nullable property 'Column' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Non-nullable property 'ColumnName' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.