Vb.net 如何检查Access数据库中是否存在主键

我想使用VB.Net和OleDb检查Access数据库中是否存在主键：

• 按主键名称

• 按字段数作为主键

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发件人：

Public Shared Function getKeyNames(tableName As [String], conn As DbConnection) As List(Of String)
    Dim returnList = New List(Of String)()


    Dim mySchema As DataTable = TryCast(conn, OleDbConnection).GetOleDbSchemaTable(OleDbSchemaGuid.Primary_Keys, New [Object]() {Nothing, Nothing, tableName})


    ' following is a lengthy form of the number '3' :-)
    Dim columnOrdinalForName As Integer = mySchema.Columns("COLUMN_NAME").Ordinal

    For Each r As DataRow In mySchema.Rows
        returnList.Add(r.ItemArray(columnOrdinalForName).ToString())
    Next

    Return returnList
End Function