Microsoft Access压缩表中的多行

Question

我在MS Access 2007中有一个问题,我希望有人有答案.我有一个很长但很简单的表,其中包含客户名称以及交付周的日期.我想通过将名称和所有日期列入一个新字段"ALLDays",同时仍然保留所有数据来总结此表.

源表看起来像这样:

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

我想有一个返回如下结果的查询:

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

谢谢.

Answer 1

通常,您必须编写一个允许您创建连锁列表的函数.这是我用过的:

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的版本具有附加功能,您可以传递值数组而不是SQL语句.

示例查询可能如下所示:

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