MYSQL中可以为字段和表名等取别名如: 1)SELECT a.username,a.order FROM orders AS a INNER JOIN user AS b ON a.username=b.username; --为表取别名 2)SELECT COUNT(goods_id) AS totalGoods FROM tdb_goods; --为字段取别名 1)中为表取别名,避免了二义性,如果ON后面的条件改为username=username,显然 会报错的,当然也可以改为ord
当需要在WPF程序启动时,启动另一外部程序(.exe程序)时,可以按照下面的例子来: C#后台代码如下: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows; using System.Windows.Controls; using System.Windows.Data; u