SQL语句更新库存表，运行错误，请帮忙更改

Private Sub Cmadd_Click()




    Dim strSql As String
    If IsNull(Me!chbm) Then
        MsgBox "请输入存货编码", , "提示"
        Me!chbm.SetFocus
        Exit Sub


    ElseIf IsNull(Me!mc) Then
        MsgBox "请输入名称", , "提示"
        Me!mc.SetFocus
        Exit Sub
    ElseIf IsNull(Me!gg) Then
        MsgBox "请输入规格", , "提示"
        Me!gg.SetFocus
        Exit Sub
    ElseIf IsNull(Me!dw) Then
        MsgBox "请输入单位", , "提示"
        Me!dw.SetFocus
        Exit Sub
    ElseIf IsNull(Me!rksl) Then
        MsgBox "请输入入库数量", , "提示"
        Me!rksl.SetFocus
        Exit Sub
    ElseIf IsNull(Me!rkrq) Then
        MsgBox "请输入入库日期", , "提示"
        Me!rkrq.SetFocus
        Exit Sub
    End If




    SQL = "select * from 库存表 where 存货编码=" & Me.chbm
    SQL = SQL & "and 存货编码=" & Me.chbm
    Set rst = New ADODB.Recordset
    rst.ActiveConnection = CurrentProject.Connection
    rst.CursorType = adOpenDynamic
    rst.LockType = adLockOptimistic
    rst.Open SQL


    With rst
        .AddNew
        !存货编码 = Me.chbm
        !名称 = Me.mc
        !规格 = Me.gg
        !单位 = Me.dw
        !库存数量 = Me.rksl


    End With
    rst.Update
    MsgBox "入库成功!请查看详细信息"
    Exit Sub
    Me.Visible = False




    rst.Close
    Set rst = Nothing
    MsgBox "系统中没有该信息,请先添加"
    Exit Sub
    Me.Visible = False




End Sub