Inserting Weekends into Table with only Weekdays MS Access

Question

I\'m needing to insert the weekends into a table that only has weekdays and then assign the last known value to the weekend values. I know I\'m going to need an Insert Query, al

Answer 1

This is a SQL based solution.

This gets all records where for customer x exists records for Friday + the following Monday but not for Saturday.

SELECT a1.*
FROM Archive a1
INNER JOIN Archive a2 ON (
       (a1.Nbr = a2.Nbr) 
   AND (a1.ExtendedNbr = a2.ExtendedNbr) 
   AND (a1.ValDate + 3 = a2.ValDate) 
   AND (DatePart("w", a1.ValDate) = 6)
  )
WHERE NOT EXISTS
(SELECT * FROM Archive a3 
 WHERE a3.Nbr = a1.Nbr
 AND a3.ValDate = a1.ValDate + 1)

and you can use that to insert the Saturdays:

INSERT INTO Archive ([Customer Name], Nbr, City, [Value of Day], ExtendedNbr, ValDate)
SELECT a1.[Customer Name], a1.Nbr, a1.City, a1.[Value of Day], a1.ExtendedNbr, a1.ValDate + 1
FROM Archive a1
INNER JOIN Archive a2 ON (
       (a1.Nbr = a2.Nbr) 
   AND (a1.ExtendedNbr = a2.ExtendedNbr) 
   AND (a1.ValDate + 3 = a2.ValDate) 
   AND (DatePart("w", a1.ValDate) = 6)
  )
WHERE NOT EXISTS
(SELECT * FROM Archive a3 
 WHERE a3.Nbr = a1.Nbr
 AND a3.ValDate = a1.ValDate + 1)

To insert the Sundays, use the same, but replace + 1 by + 2 in both places.

To insert random single missing days (bank holidays), change a1.ValDate + 3 to a1.ValDate + 2, and remove AND (DatePart("w", a1.ValDate) = 6)

Edit

An alternate version if DatePart() inside JOIN gives trouble:

INSERT INTO Archive ([Customer Name], Nbr, City, [Value of Day], ExtendedNbr, ValDate)
SELECT a1.[Customer Name], a1.Nbr, a1.City, a1.[Value of Day], a1.ExtendedNbr, a1.ValDate + 1
FROM Archive a1
INNER JOIN Archive a2 ON (
       (a1.Nbr = a2.Nbr) 
   AND (a1.ExtendedNbr = a2.ExtendedNbr) 
   AND (a1.ValDate + 3 = a2.ValDate) 
  )
WHERE NOT EXISTS
(SELECT * FROM Archive a3 
 WHERE a3.Nbr = a1.Nbr
 AND a3.ValDate = a1.ValDate + 1)
AND (DatePart("w", a1.ValDate) = 6)