Question

I have an Update query that says it’s updating 1029 rows, when there are only 994 rows in the database that it’s updating.

The query references an external Excel file and updates the “Master Calendar” with “Posted Date” when the batch numbers are equivalent:

UPDATE [Mapped Link] RIGHT JOIN Master_Calendar ON [Mapped Link].Reference = Master_Calendar.[Batch Number] SET Master_Calendar.[Actual Posted Date] = [Mapped Link]. [Entry Date];

Whenever rows get added to the external ‘Mapped Link’ document, the rows increase on the update query. There are about 2000 rows in ‘Mapped Link’, so it’s not adding the rows from Master Calendar to Mapped Link together.

The data doesn’t seem to be updating incorrectly — all the data is correct. But how can it be updating more rows than it exists? Is it just counting wrong? Thoughts?

Thanks, guys.

Answer 1

You have either duplicates in either Master_Calendar.[Actual Posted Date] or [Mapped Link].[Entry Date]

To check for duplicate dates, you can run a query. For example:

SELECT [Actual Posted Date], Count(ID) AS CountOfID
FROM Master_Calendar
GROUP BY [Actual Posted Date]
HAVING Count(ID)>1

You will need to change ID to the name of the index on your table.