SQL set values of one column equal to values of another column in the same table

Question

I have a table with two DATETIME columns.

One of them is never NULL, but one of them is sometimes NULL.

I need to write a query which will set all the NULL rows

Answer 1

Here is sample code that might help you coping Column A to Column B:

UPDATE YourTable
SET ColumnB = ColumnA
WHERE
ColumnB IS NULL
AND ColumnA IS NOT NULL;