select * from biao where one like '%"+textbox1+"%' and two like '%"+textbox2+"%' and ……

这样不好
如果有一个不输入或者不选择
就无法查询出数据

可以查询出来的

也可以写成：
select * from biao where (textbox1.text='' or one like '%"+textbox1.text+"%') and (textbox2.text='' or two like '%"+textbox2+"%')...
这样子就能实现不输入就不检查该条件，数据就检查该条件

用where 1=1
and ...
and ...
这样的方法最好.

我觉得把这种组合查询条件的任务交给程序比较好，不要让数据库太累。

上网搜多条件查询，一大把啊！
public static string GetSearchString(string testTime,string taste,string oversight,string area,string city,string place)
    {
        string SELECT_STRING = "select Project.*,[Plan].Taste,tb_city.city as sCity,tb_venues.Venues as sPlace from Project,[Plan],tb_city,tb_venues,tb_area where " +
                                 "1=1 ";
        if (testTime != "")
            SELECT_STRING += " and BeginDate='" + testTime + "'";
        if (taste != "")
            SELECT_STRING+=" and Taste like '%"+taste+"%'";
        if (oversight != "")
            SELECT_STRING += " and OverSight='" + oversight + "'";
        if (area != "")
            SELECT_STRING += " and Project.Place in (select VID from tb_city,tb_area,tb_venues where tb_area.AID=tb_City.AID and tb_city.CID=tb_venues.CID and Area='"+area+"')";
      
        if (city != "")
            SELECT_STRING += " and tb_city.City='" + city + "'";
        if (place != "")
            SELECT_STRING += " and tb_venues.Venues like '%" + place + "%'";

        return SELECT_STRING;
    }