Question

ASP.NET,C#,SQL建有表1和表2，从表1中选取行写入表2，设定表2最多有3行数据，若写入时已有3行则删除最早行

Answer 1

DataRow row = DB.GetDataTable("SELECT TOP 1 * FROM Table1").Rows[0];// 表1获取到的内容
int Count = DB.GetCount("SELECT COUNT(*) FROM Table2"); //取得表2的行数
if(Count == 3)//如果行数等于3
{
DB.Execute("DELETE Table2 WHERE ID = (SELECT MIN(ID) FROM Table2"); //删除首行
}
DB.Execute("INSERT INTO Table2 (ID,Name) VALUES (@ID,@Name)",new SqlParameter[]{
new SqlParameter("@ID",int.Parse(row["ID"].ToString())),
new SqlParameter("@Name",row["Name"].ToString())
}); //插入表1渠道的数据