SQL顺序和查询结果的限制

Question

我有一个查询，按列a 排序行，并且限制为100.然后我想对该结果运行一个查询，该查询按 b列排序行并限制在50岁之内。

我该怎么做？

Answer 1

在派生表中执行第一个order by / limit。然后在派生表的结果上执行第二个order by / limit：

select * from
(
select * from tablename
order by a
limit 100
) dt
order by b
limit 50

Answer 2

您应该使用Protected Sub EPACheck_Clicked(ByVal sender As Object, ByVal e As EventArgs) Dim ckbx As CheckBox = CType(sender, CheckBox) Dim dgItem As DataGridItem = CType(ckbx.NamingContainer, DataGridItem) Dim rcDelete As String = dgItem.ItemIndex CType(Session("mytable"), DataTable).Rows.RemoveAt(Convert.ToInt32(rcDelete)) BindgrdEPA() End Sub 声明：

select from select