Microsoft Access condense multiple lines in a table

Question

I have a question in MS Access 2007 and I hope someone has the answer. I have a long but simple table containing customer names and the days of the week that deliveries are made. I would like to summarize this table by listing the name and all the days into one new field "ALLDays" while still preserving all the data.

The source table looks something like this:

Name         Day  
CustomerA    Monday  
CustomerA    Thursday  
CustomerB    Tuesday  
CustomerB    Friday  
CustomerC    Wednesday  
CustomerC    Saturday  

I would like to have a query which returns results like this:

Name         ALLDays  
CustomerA    Monday, Thursday  
CustomerB    Tuesday, Friday  
CustomerC    Wednesday, Saturday  

Thanks.

Answer 1

Typically you have to write a function that will allow you to create a concatenated list. Here's what I've used:.

Public Function GetList(SQL As String _
                            , Optional ColumnDelimeter As String = ", " _
                            , Optional RowDelimeter As String = vbCrLf) As String
'PURPOSE: to return a combined string from the passed query
'ARGS:
'   1. SQL is a valid Select statement
'   2. ColumnDelimiter is the character(s) that separate each column
'   3. RowDelimiter is the character(s) that separate each row
'RETURN VAL: Concatenated list
'DESIGN NOTES:
'EXAMPLE CALL: =GetList("Select Col1,Col2 From Table1 Where Table1.Key = " & OuterTable.Key)

Const PROCNAME = "GetList"
Const adClipString = 2
Dim oConn As ADODB.Connection
Dim oRS As ADODB.Recordset
Dim sResult As String

On Error GoTo ProcErr

Set oConn = CurrentProject.Connection
Set oRS = oConn.Execute(SQL)

sResult = oRS.GetString(adClipString, -1, ColumnDelimeter, RowDelimeter)

If Right(sResult, Len(RowDelimeter)) = RowDelimeter Then
    sResult = Mid$(sResult, 1, Len(sResult) - Len(RowDelimeter))
End If

GetList = sResult
oRS.Close
oConn.Close

CleanUp:
    Set oRS = Nothing
    Set oConn = Nothing

Exit Function
ProcErr:
    ' insert error handler
    Resume CleanUp

End Function

Remou's version has the added feature that you can pass an array of values instead of a SQL statement.

---

Sample query might look like:

SELECT SourceTable.Name
    , GetList("Select Day From SourceTable As T1 Where T1.Name = """ & [SourceTable].[Name] & """","",", ") AS Expr1
FROM SourceTable
GROUP BY SourceTable.Name;