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问题描述

我有一个表格,其中包含运行编号.然后将其链接到第二个表,该表包含每次运行的面板的序列号.我想知道是否可以设计一个查询,该查询将为每个运行号提供序列号.

I have a table that contains run numbers. This is then linked to a second table that contains the serial numbers of the panels that go through each run. I was wondering is it possible to design a query that will give for each run number the serial numbers.

我希望在类似以下的表格中

I would like it in a table like:

运行编号1,第一个序列号为1,第二个序列号为1,等等.

Run Number1, First Serial Number for 1, Second Serial Number for 1, etc..

运行编号2,第2个序列号,第2个序列号,依此类推.

Run Number2, First Serial Number for 2, Second Serial Number for 2, etc..

我可以填写以下表格:

运行编号1,第一个序列号

Run Number1, First Serial Number for 1

运行编号1,第二个序列号1

Run Number1, Second Serial Number for 1

运行编号2,第2个序列号

Run Number2, First Serial Number for 2

运行编号2,第二个序列号2

Run Number2, Second Serial Number for 2

是否可以进行设置?

推荐答案

您可以使用我的 DJoin 函数,因为它将接受SQL作为源,因此您不需要其他已保存的查询:

You can use my DJoin function as this will accept SQL as the source, thus you won't need additional saved queries:

' Returns the joined (concatenated) values from a field of records having the same key.
' The joined values are stored in a collection which speeds up browsing a query or form
' as all joined values will be retrieved once only from the table or query.
' Null values and zero-length strings are ignored.
'
' If no values are found, Null is returned.
'
' The default separator of the joined values is a space.
' Optionally, any other separator can be specified.
'
' Syntax is held close to that of the native domain functions, DLookup, DCount, etc.
'
' Typical usage in a select query using a table (or query) as source:
'
'   Select
'       KeyField,
'       DJoin("[ValueField]", "[Table]", "[KeyField] = " & [KeyField] & "") As Values
'   From
'       Table
'   Group By
'       KeyField
'
' The source can also be an SQL Select string:
'
'   Select
'       KeyField,
'       DJoin("[ValueField]", "Select ValueField From SomeTable Order By SomeField", "[KeyField] = " & [KeyField] & "") As Values
'   From
'       Table
'   Group By
'       KeyField
'
' To clear the collection (cache), call DJoin with no arguments:
'
'   DJoin
'
' Requires:
'   CollectValues
'
' 2019-06-24, Cactus Data ApS, Gustav Brock
'
Public Function DJoin( _
    Optional ByVal Expression As String, _
    Optional ByVal Domain As String, _
    Optional ByVal Criteria As String, _
    Optional ByVal Delimiter As String = " ") _
    As Variant

    ' Expected error codes to accept.
    Const CannotAddKey      As Long = 457
    Const CannotReadKey     As Long = 5
    ' SQL.
    Const SqlMask           As String = "Select {0} From {1} {2}"
    Const SqlLead           As String = "Select "
    Const SubMask           As String = "({0}) As T"
    Const FilterMask        As String = "Where {0}"

    Static Values   As New Collection

    Dim Records     As DAO.Recordset
    Dim Sql         As String
    Dim SqlSub      As String
    Dim Filter      As String
    Dim Result      As Variant

    On Error GoTo Err_DJoin

    If Expression = "" Then
        ' Erase the collection of keys.
        Set Values = Nothing
        Result = Null
    Else
        ' Get the values.
        ' This will fail if the current criteria hasn't been added
        ' leaving Result empty.
        Result = Values.Item(Criteria)
        '
        If IsEmpty(Result) Then
            ' The current criteria hasn't been added to the collection.
            ' Build SQL to lookup values.
            If InStr(1, LTrim(Domain), SqlLead, vbTextCompare) = 1 Then
                ' Domain is an SQL expression.
                SqlSub = Replace(SubMask, "{0}", Domain)
            Else
                ' Domain is a table or query name.
                SqlSub = Domain
            End If
            If Trim(Criteria) <> "" Then
                ' Build Where clause.
                Filter = Replace(FilterMask, "{0}", Criteria)
            End If
            ' Build final SQL.
            Sql = Replace(Replace(Replace(SqlMask, "{0}", Expression), "{1}", SqlSub), "{2}", Filter)

            ' Look up the values to join.
            Set Records = CurrentDb.OpenRecordset(Sql, dbOpenSnapshot)
            CollectValues Records, Delimiter, Result
            ' Add the key and its joined values to the collection.
            Values.Add Result, Criteria
        End If
    End If

    ' Return the joined values (or Null if none was found).
    DJoin = Result

Exit_DJoin:
    Exit Function

Err_DJoin:
    Select Case Err
        Case CannotAddKey
            ' Key is present, thus cannot be added again.
            Resume Next
        Case CannotReadKey
            ' Key is not present, thus cannot be read.
            Resume Next
        Case Else
            ' Some other error. Ignore.
            Resume Exit_DJoin
    End Select

End Function

' To be called from DJoin.
'
' Joins the content of the first field of a recordset to one string
' with a space as delimiter or an optional delimiter, returned by
' reference in parameter Result.
'
' 2019-06-11, Cactus Data ApS, Gustav Brock
'
Private Sub CollectValues( _
    ByRef Records As DAO.Recordset, _
    ByVal Delimiter As String, _
    ByRef Result As Variant)

    Dim SubRecords  As DAO.Recordset

    Dim Value       As Variant

    If Records.RecordCount > 0 Then
        While Not Records.EOF
            Value = Records.Fields(0).Value
            If Records.Fields(0).IsComplex Then
                ' Multi-value field (or attachment field).
                Set SubRecords = Records.Fields(0).Value
                CollectValues SubRecords, Delimiter, Result
            ElseIf Nz(Value) = "" Then
                ' Ignore Null values and zero-length strings.
            ElseIf IsEmpty(Result) Then
                ' First value found.
                Result = Value
            Else
                ' Join subsequent values.
                Result = Result & Delimiter & Value
            End If
            Records.MoveNext
        Wend
    Else
        ' No records found with the current criteria.
        Result = Null
    End If
    Records.Close

End Sub

完整的文档可以在我的文章中找到:

Full documentation can be found in my article:

从表或查询的一个字段中加入(合并)值

如果您没有帐户,请浏览链接:阅读全文.

If you don't have an account, browse to the link: Read the full article.

代码也在 GitHub 上: VBA.DJoin

这篇关于如何设计查询以给出链接到每组数据的每个相关字段的名称的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!

10-29 09:30