Question

我需要将这两个单独的查询合并为一个，因为它效率不高并且从Classic ASP转换为C＃ASP.NET

SQL = "SELECT MemID FROM network WHERE userid='"&strTemp&"'"
Set rsNet = Conn.Execute(SQL)
if NOT rsNet.eof then
strList = rsNet("memID")
end if
rsNet.close
set rsNet = Nothing

SQL = "SELECT Distinct userid, username, img1, birthday, gendid, city, state, country, title FROM UserInfo WHERE (userinfo.userid IN (" & strList & ")) "
Set rsView = Server.CreateObject("ADODB.Recordset")
rsView.Open SQL, Conn, adOpenKeyset, adLockReadOnly
if NOT rsView.EOF then
arrN = rsView.getrows()
end if
rsView.close
set rsview = nothing

Answer 1

我不知道C＃，但SQL转到了经典的连接......

SELECT userid, username, img1, birthday, gendid, city, state, country, title
FROM UserInfo
JOIN network
ON network.MemID = userinfo.userid
AND network.userid = :inputUserId

如果由于某种原因您有非唯一行，则只需要DISTINCT。

Answer 2

DataTable dtTable = null;
using (SqlConnection oConn = new SqlConnection("Your connection string"))
{
   string strQuery = @"SELECT Distinct userid, username, img1, birthday, gendid, city, state, country, title 
   FROM UserInfo 
   WHERE userinfo.userid IN 
   (
      SELECT MemID 
      FROM network
      WHERE userid= @userid 
    )";
   SqlDataAdapter oDataAdapter = new SqlDataAdapter(strQuery, oConn);
   oDataAdapter.Fill(dtTable, "TableName");

}

Answer 3

@ X-Zero的选择很好 - 有一件事就是参数是@uinputUserID，而不是：inputUserId，如果你使用的是microsoft（sql-server）。

否则，将其转换为asp.net（使用c＃）取决于您要使用的控件 - 数据集，数据表，数据源，datareader等... @ Mr.先生的数据表是一个好方法，但是然后你需要将它数据绑定到任何使用它的控件。

Answer 4

试试这个（如果您不熟悉ADO.NET使用的权限，我会包含using语句）：

using System.Data;
using System.Data.SqlClient

public DataTable GetUserDetails(int userID)
{
    DataTable dTable = new DataTable();

    using (SqlConnection con = new SqlConnection(<your connection string>))
    {

        con.Open();

        SqlCommand cmd = new SqlCommand();

        cmd.Parameters.Add(new SqlParameter("@userid", userID);
        cmd.Text = "SELECT DISTINCT u.userid, u.username, u.img1, u.birthday, u.genid, u.city, u.state, u.country, u.title FROM UserInfo u JOIN Network n ON u.userid = n.userid WHERE n.userid = ?";
        cmd.CommandType = CommandType.Text;
        cmd.Connection = con;

        SqlDataAdapter da = new SqlDataAdapter(cmd);        

        da.Fill(dTable);
    }

    return dTable;
}

Answer 5

这并不像其他答案所认为的那样微不足道，因为看起来MemId是逗号分隔的字符串字段（糟糕的数据库设计）。因此，您必须在...内部使用动态SQL。

using (SqlConnection conn = new SqlConnection(@"ConnectionStringHere"))
{
    conn.Open();

    IDbCommand cmd = conn.CreateCommand();

    cmd.CommandText = @"
        DECLARE @sql nvarchar(MAX)

        SET @sql = '
            SELECT DISTINCT
                userid, username, img1, birthday,
                            gendid, city, state, country, title 
                FROM UserInfo 
                WHERE UserId IN 
                (' + (SELECT MemID FROM network WHERE UserId = @userId) + ')'

        EXEC(@sql)";

    IDbDataParameter param = cmd.CreateParameter();
    param.DbType = DbType.String;
    param.Value = "12345"; // TODO
    param.ParameterName = "@userId";

    cmd.Parameters.Add(param);

    IDataReader dr = null;

    try
    {
        dr = cmd.ExecuteReader();

        // TODO: Process result set
    }
    finally
    {
        if (dr != null)
            dr.Close();
    }
}

将2个SQL查询合并为一个查询并转换为C＃

5 个答案: