Xmpp Vs Websocket(Xmpp Vs Websocket)

 当速度至关重要时，SQL case语句甚至可能是最快的（我将运行测试）但是为了可维护性，将普通值返回到表示层（或某些业务层）是最佳选择。 
 
 [update]运行了一些快速而肮脏的测试（下面的代码），发现C＃代码变体比SQL case变体略快。 结论：返回“原始”数据并在表示层中对其进行操作既更快又更易于维护。 
 
 -Edoode 
 
 我在下面查询了196288行。 
 
StringBuilder result = new StringBuilder();
using (SqlConnection conn = new SqlConnection(Settings.Default.Conn))
{                
    conn.Open();
    string cmd = "select [state], case [state] when 'ca' then 'california' else [state] end from member";
    SqlCommand command = new SqlCommand(cmd, conn);
    using (SqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection))
    {
        while (reader.Read())
        {                        
            result.AppendLine(reader.GetString(1));
        }
    }
}
 
 C＃变种： 
 
StringBuilder result = new StringBuilder();
using (SqlConnection conn = new SqlConnection(Settings.Default.Conn))
{

    conn.Open();
    string cmd = "select [state] from member";
    SqlCommand command = new SqlCommand(cmd, conn);
    using (SqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection))
    {
        while (reader.Read())
        {
            result.AppendLine(reader.GetString(0) == "ca" ? "california" : reader.GetString(0));
        }
    }
 
 } 

When speed is of the essence, the SQL case statements might even be the fastest (I'll run a test) but for maintainability, returning the plain values to the presentation layer (or some business layer thingy) is the best option. 
 
[update] ran some quick and dirty tests (code below) and found the C# code variant slightly faster than the SQL case variant. Conclusion: returning the 'raw' data and manipulating it in the presentation layer is both quicker and more maintainable.
 
-Edoode
 
I retrieved 196288 rows with queries below.
 
StringBuilder result = new StringBuilder();
using (SqlConnection conn = new SqlConnection(Settings.Default.Conn))
{                
    conn.Open();
    string cmd = "select [state], case [state] when 'ca' then 'california' else [state] end from member";
    SqlCommand command = new SqlCommand(cmd, conn);
    using (SqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection))
    {
        while (reader.Read())
        {                        
            result.AppendLine(reader.GetString(1));
        }
    }
}
 
C# variant:
 
StringBuilder result = new StringBuilder();
using (SqlConnection conn = new SqlConnection(Settings.Default.Conn))
{

    conn.Open();
    string cmd = "select [state] from member";
    SqlCommand command = new SqlCommand(cmd, conn);
    using (SqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection))
    {
        while (reader.Read())
        {
            result.AppendLine(reader.GetString(0) == "ca" ? "california" : reader.GetString(0));
        }
    }
 
}