vba function/procedure to build a concatenated string to update a field value

Update null values in a table, [login to view URL], with a variable length concatenated string. The concatenated string is built by isolating each new value to concatenate from tlkpPrLy using 3 fixed (red) and 1 variable join (blue). The variable join connects each successive field in ttblHd beginning with “col” to [login to view URL], i.e. col01, then col02, etc. The number of columns starting with “Col” will vary over time. The number in the field name, “col02”, should match the value in [login to view URL] (green) *graphic with color coding in attached file For your convenience sample SQL to isolate and build a concatenated string for the first 3 columns is below: 1 UPDATE ((ttblHd INNER JOIN tlkpPrHd ON [login to view URL] = [login to view URL]) INNER JOIN tlkpHdPr ON ([login to view URL] = [login to view URL]) AND ([login to view URL] = [login to view URL])) INNER JOIN tlkpPrLy ON [login to view URL] = [login to view URL] SET [login to view URL] = [ttblHd].[strLy] & [tlkpPrLy].[strAaK] WHERE ((([login to view URL])=1) AND (([login to view URL])=False) AND (([login to view URL])=True)); 2 UPDATE ((ttblHd INNER JOIN tlkpPrHd ON [login to view URL] = [login to view URL]) INNER JOIN tlkpHdPr ON ([login to view URL] = [login to view URL]) AND ([login to view URL] = [login to view URL])) INNER JOIN tlkpPrLy ON [login to view URL] = [login to view URL] SET [login to view URL] = [ttblHd].[strLy] & [tlkpPrLy].[strAaK] WHERE ((([login to view URL])=2) AND (([login to view URL])=False) AND (([login to view URL])=True)); 3 UPDATE (tlkpHdPr INNER JOIN (ttblHd INNER JOIN tlkpPrHd ON [login to view URL] = [login to view URL]) ON ([login to view URL] = [login to view URL]) AND ([login to view URL] = [login to view URL])) INNER JOIN tlkpPrLy ON [login to view URL] = [login to view URL] SET [login to view URL] = [ttblHd].[strLy] & [tlkpPrLy].[strAaK] WHERE ((([login to view URL])=3) AND (([login to view URL])=False) AND (([login to view URL])=True)); Expected output: See table ttblHd field strLy for the expected output of the procedure/function. Database objects: The attached database contains: • ttblHd • tlkpHdPr • tlkpPrHd • tlkpPrLy • frmTest Requirements: 1) The procedure/function output replicates the current values in ttblHd.strLy. 2) The procedure/function executes from cmdTest on frmTest