数据库: ID Stud_no Stud_course1
自动编号 123 (空值)===============================================================================================
public static bool insert(string que) //在类adm下的函数
{ //根据传进来的SQL语句执行插入/删除/更新等操作
OleDbConnection con = adm.con();
con.Open();
OleDbCommand cmd = new OleDbCommand(que, con);
int count = Convert.ToInt32(cmd.ExecuteNonQuery());
if (count > 0)
{
con.Close();
return true;
}
else
{
con.Close();
return false;
}
============================================================================================ string aaa = "123"; bool back = adm.insert("update student set Stud_course1 = '" + idd + "' where Stud_course1='' and Stud_no='" + aaa + "'"); if (back)
Response.Write("<script>alert('添加成功!');</script>");按理说我运行之后back=ture也就是count要>0,可是为什么count=0
?????
帮忙一下,在线等待!!!!
自动编号 123 (空值)===============================================================================================
public static bool insert(string que) //在类adm下的函数
{ //根据传进来的SQL语句执行插入/删除/更新等操作
OleDbConnection con = adm.con();
con.Open();
OleDbCommand cmd = new OleDbCommand(que, con);
int count = Convert.ToInt32(cmd.ExecuteNonQuery());
if (count > 0)
{
con.Close();
return true;
}
else
{
con.Close();
return false;
}
============================================================================================ string aaa = "123"; bool back = adm.insert("update student set Stud_course1 = '" + idd + "' where Stud_course1='' and Stud_no='" + aaa + "'"); if (back)
Response.Write("<script>alert('添加成功!');</script>");按理说我运行之后back=ture也就是count要>0,可是为什么count=0
?????
帮忙一下,在线等待!!!!
你从哪里看到的count值呢?
OledbCommand cmd=new OledbCommand("update update student set Stud_course1=@id where
Stud_course1 is null and stud_no=@no");OledbParameter[] params=new OledbParameter[]{new OledbParameter("@id",SqlDbType.varchar),
new OledbParameter("@no",SqlDbType.varchar), }params[0].value="";
params[1].value="";cmd.Parameter.add(params);
cmd.ExecuteNoQuery();
大概这个意思。代码可能不对,懒得开studio了
一处是空格的问题
一个是isnull的问题吧
建议用
Stud_course1 is null and studion=''
这样还不行的话 那就去到数据库
set nocount off ---(ms Sql)
我帮你写吧:
string sql="update student set Stud_course1 = '" + idd + "' where ISNULL(Stud_course1,'')='' and Stud_no='" + aaa + "'";