小编BKl*_*BKl的帖子

我有两张桌子.不同之处在于存档是一个表而另一个存放当前记录.这些是记录公司销售额的表格.在这两个领域我们都有:id,名称,销售价格.我需要从两个表中选择给定名称的最高价和最低价.我试着用这个查询:

select name, max (price_of_sale), min (price_of_sale)
from wapzby
union
select name, max (price_of_sale), min (price_of_sale)
from wpzby
order by name

但是这样的调查给了我两条记录 - 一张当前的表,一张表档案.我想立即从两个表中选择最小和最大价格的名称.我如何获得此查询？

我有一个ado.net代码列表:

OleDbConnection oconn = new OleDbConnection();
                //   oconn.ConnectionString ="Driver={Microsoft Visual FoxPro Driver};Provider=vfpoledb.1;SourceType=DBF;SourceDB=" + pelna_sciezka + ";Exclusive=No; Collate=Machine;NULL=NO;DELETED=NO;BACKGROUNDFETCH=NO;";
                oconn.ConnectionString = "Provider=vfpoledb.1;Data Source=" + pelna_sciezka + ";Collating Sequence=machine";
                oconn.Open();
                OleDbCommand ocmd = oconn.CreateCommand();
                string na = TBNazwaKonta.Text.Replace("\n","");
                na = na.Replace("\r","") ;
                string ks2 = ks.Replace("\n","");
                ks2 = ks2.Replace("\r", "");
                 OleDbCommand dbCmdNull = oconn.CreateCommand();
                dbCmdNull.CommandText = "SET NULL OFF";
                dbCmdNull.ExecuteNonQuery();                
                string zapytanie = @"insert into " + @pelna_sciezka + @" (rk, Na,Ks) values (0,'" + na + "','" + ks2 +"')";
                ocmd.CommandText = …