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我正在制作一个相当简单的库存跟踪数据库。我想通过 ID 检索记录，并在金额中添加或删除指定的数字。如果它不存在，我想添加它。甚至可以在不绑定到表的情况下执行此操作吗？

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2 回答 2

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听起来你有一个候选ID值。也许它包含在一个名为MyID. 并且您还有另一个数值MyAmtChange，它将添加到表中为字段值匹配amount的行命名的字段中的值中。 IDMyID

一个复杂的问题是您的表中可能没有ID值匹配的行MyID。在这种情况下，您需要为其添加一行。

如果那是正确的，当一个不存在时，INSERT一行。MyID然后你可以简单地UPDATE在amount匹配的行中MyID。

Dim strInsert As String
Dim strUpdate As String
Dim db As DAO.Database

Set db = CurrentDb
If DCount("*", "YourTableNameHere", "ID = " & MyID) = 0 Then
    strInsert = "INSERT INTO YourTableNameHere (ID)" & vbCrLf & _
        "VALUES (" & MyID & ");"
    Debug.Print strInsert
    db.Execute strInsert, dbFailOnError
End If

strUpdate = "UPDATE YourTableNameHere" & vbCrLf & _
    "SET amount = Nz(amount, 0) + " & MyAmtChange & vbCrLf & _
    "WHERE ID = " & MyID & ";"
Debug.Print strUpdate
db.Execute strUpdate, dbFailOnError
Set db = Nothing

如果这个猜测相当接近，则向该代码添加一个错误处理程序块，以处理dbFailOnError... 或任何其他错误出现的任何问题。

于 2012-10-07T19:38:38.760 回答
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我不知道你到底想要什么，但这段代码展示了如何使用 VB-Access 操作数据。 

Sub fnStudent()
    On Error GoTo insertError
    Dim studentQuery As String
    'INSERTING INTO TABLE
        studentQuery = "INSERT INTO Students values ('10','YAHYA','02/10/2012')"
        CurrentDb.Execute studentQuery, dbFailOnError
    'UPDATING
        studentQuery = "UPDATE Students Set name='YAHYA OULD ABBA' WHERE stdID='10'"
        CurrentDb.Execute studentQuery, dbFailOnError
    'LISTING VALUES
    Dim studentsRS As Recordset
    Set studentsRS = CurrentDb.OpenRecordset("SELECT * FROM Students WHERE upper(name) like '%YAHYA%';")
    Do While Not studentsRS.EOF
        MsgBox "ID : " & studentsRS.Fields(0) & "Name : " & studentsRS.Fields(1) & "Birth Date : " & studentsRS.Fields(2)
        studentsRS.MoveNext
    Loop
    'DELETING
    studentQuery = "DELETE FROM Students WHERE stdID='10'"
    CurrentDb.Execute studentQuery, dbFailOnError
    Exit Sub 'exit if there was no error
    'UPDATE:
errorHandler:
    If Err.Number = 3022 Then
            MsgBox "Can't have duplicate key; index changes were unsuccessful",     vbMsgBoxRtlReading + vbCritical, "Error " & Err.Number
    Else : MsgBox "Error" & vbCrLf & Err.Description, vbMsgBoxRtlReading + vbCritical, "Error " & Err.Number
    End If
End Sub

在这里您可以找到vba错误列表http://www.halfile.com/vb.html

于 2012-10-02T12:28:57.680 回答