参考代码
Dim cn As new ADODB.Connection()
Dim ca As new ADOX.Catalog
cn.Open(Connections("test").ConnectionString , Nothing, Nothing, -1)
Ca.ActiveConnection = cn
Dim tbl = ca.Tables("外部表")
tbl.Columns.Append("_Locked", ADOX.DataTypeEnum.adBoolean)
tbl.Columns.Append("_Sortkey", ADOX.DataTypeEnum.adDouble)
cn.Close()
ca = Nothing
http://blog.csdn.net/kfhzy/article/details/6020283