sql语句批量更新数据库所有表，执行不正常

Question

1、我使用以下语句给每一个表添加列是成功的。

  Public Function FIXTable(ByVal TBLname As String) As String
        Using connection As New SqlClient.SqlConnection(cs)
            connection.Open()
            'Dim sqlstr As String = "Alter table " + TBLname + " add 定额编号 VARCHAR(25)"
            Dim cmd As New SqlClient.SqlCommand(sqlstr, connection)
            Try
               cmd.ExecuteNonQuery()
            Catch ex As Exception
            End Try
        End Using
        Return 0
    End Function

2、但我将SQL语句更改为插入、删除语句，然后查看数据库却发现没有被更改，程序没有报任何错误。

  Public Function FIXTable(ByVal TBLname As String) As String
        Using connection As New SqlClient.SqlConnection(cs)
            connection.Open()
                        ' Dim sqlstr As String = "update " + TBLname + " set '定额编号' =" + TBLname + "where '电算号'<>0"
            Dim sqlstr As String = "del from  " + TBLname + "  where  '电算号'  <> " & 0
                       Dim cmd As New SqlClient.SqlCommand(sqlstr, connection)
            Try
                ' cmd.ExecuteNonQuery()
                cmd.ExecuteScalar()
            Catch ex As Exception
            End Try
        End Using
        Return 0
    End Function

---

http://hi.baidu.com/useek/blog