Ms-access – Rename cell based on duplicate compound key in MS Access

ms access

I'm using MS Access (I know, I know…), and I'm trying to rename a cell when there are duplicates of mutliple columns.

Here's an example:

Col_1   Col_2   Col_3   Note
A1      B1      C1      
A1      B2      C1      Not a Dup
A1      B1      C2      Not a Dup
A2      B2      C2      
A2      B2      C2      Duplicate
A3      B3      C3      
A3      B3      C3      Duplicate
A3      B3      C3      Duplicate

I would like the query or code to update Col_3 (or add another column if that's easier) as below. Note that the order of the duplication is important.

Col_1   Col_2   Col_3   Note
A1      B1      C1      
A1      B2      C1      Not a Dup
A1      B1      C2      Not a Dup
A2      B2      C2      
A2      B2      C2Dup1  Duplicate
A3      B3      C3      
A3      B3      C3Dup1  Duplicate
A3      B3      C3Dup2  Duplicate

I've seen solutions that use row_number() and over() clauses, but those just work in SQL Server.

Any thoughts for how to tackle this in Access?

Best Answer

You will need two things

First, make sure mytable as a autoincrement column called ID

Next, place this SQL in the SQL View of a Query and run it:

SELECT Col_1,Col_2,IIF(DupKey=0,Col_3,Col3+TRIM$(STR$(ID))) as Column_3 FROM 
(SELECT AA.*,
AA.ID - BB.ID as DupKey
FROM
(
   SELECT A.*,B.ID,
   IIF(DupCOunt=1,B.Col_3,B.Col_3+"Dup") AS Col3
   FROM
   (
      SELECT Col_1, Col_2, Col_3, Count(1) AS DupCount
      FROM mytable GROUP BY Col_1, Col_2, Col_3
   ) AS A, mytable AS B
   WHERE A.Col_1=B.Col_1 AND A.Col_2=B.Col_2 AND A.Col_3=B.Col_3
) as AA,
(
   SELECT A.Col_1,A.Col_2,A.Col_3,A.DupCount,MIN(B.ID) as ID
   FROM
   (
      SELECT Col_1, Col_2, Col_3, Count(1) AS DupCount
      FROM mytable GROUP BY Col_1, Col_2, Col_3
   ) AS A, mytable AS B
   WHERE A.Col_1=B.Col_1 AND A.Col_2=B.Col_2 AND A.Col_3=B.Col_3
   GROUP BY A.Col_1,A.Col_2,A.Col_3,A.DupCount
) as BB
WHERE AA.Col_1=BB.Col_1 AND AA.Col_2=BB.Col_2 AND AA.Col_3=BB.Col_3
) as AAA;

Give it a Try !!!

It will not make consecutive Dup numbers but it will assign unique Dup Numbers. This is too hard to get consecutive numbers without VB Code or another table

Firstly, a schema...

tblLocation(locationID[PK++], locationReference)
tblRoom(roomID[PK++], keyLocation[tblLocation.locationID], roomNumber)
tblRack(rackID[PK++], keyRoom[tblRoom.roomID], rackReference)
tblDevice(deviceID[pk++], keyRack[tblRack.rackID], positionU, deviceLabel)

...tables for custom devices can extend tblDevice

Foreign keys in square brackets, PK++ means an auto increment primary key.

As you can see, a Location has many Rooms, a Room has many Racks, a Rack has many Devices.

I have made primary keys as auto IDs as I prefer them to be integers and there's less to think about should you change a location/room/rack reference.

Populate this with Locations, Rooms and Racks as appropriate.

Solution 1 :: Not a lot of racks

Have three drop downs on the form.
User chooses a location, you then select all the rooms of that location in the next combobox.
User then selects the room, you then fill the next combobox with the racks in the room.
User then fills in device details and U position (which you probably want to validate to make sure that you don't have anything allocated there.)

Solution 2 :: Lots of racks

Have a query similar to:

SELECT
    rackID,
    locationReference + '-' + roomReference + '-' + rackReference AS [Full Location]
FROM tblLocation
    INNER JOIN tblRoom
        ON tblLocation.locationID = tblRoom.keyLocation
    INNER JOIN tblRack
        ON tblRoom.roomID = tblRack.keyRoom
ORDER BY
    locationReference ASC,
    roomNumber ASC,
    rackReference ASC

To generate a list of Location-Room-Rack references.

ABC-101-A/1
ABC-101-A/1
ABC-101-A/2
ABC-101-A/2
ABC-105-B8
ABC-105-B8
FAY-208-X8
FAY-210-A9T
FAY-210-A9T
FAY-210-F4
NAT-410-78
NAT-410-78

User selects one, then fills in the information. List will be equal to the number of racks (which could get a bit excessive).

Advantages

If you move a rack (or racks) of equipment from one room to another, it's just a simple update query to update the database
If a location/room/rack reference changes, you only have one piece of data to update.

Further schema additions

I've used racks in the past, I simplified the schema but these are some additions that spring to mind.

Add rackSize to tblRack: the size in U's
Add sizeU to tblDevice: the size of the device in U's

You can then do further validation: if you have a 39U rack and somebody tries to put a 5U device in at location 38, you can throw an error (as U's 40-42 don't exist!). Also if somebody puts a 3U device in at location 10, and something is in location 11, you know it won't fit or they have not updated the details of the device that is no longer there!

You could also make some clever queries that would tell you how much space there is in your racks (and where). But that's beyond the scope of this question!

Hope this helps.

MS Access – Auto-Fill ID Field Based on Another Field

Assuming that you know how to edit and run a SQL query in Access, I think you need to execute a SQL Query similar to the following:

    UPDATE FoodPurchases
    INNER JOIN Vendors ON FoodPurchases.VendorName = Vendors.VendorName
    SET FoodPurchases.VendorId  = Vendors.VendorId

I have not verified the above, so let me know if it does not work.