Is it possible to get unique results of 2 different fields in 1 query? Ex. Table Criminal Criminal name Id No No of Crimes in Past father name state is it posible to get Criminal having distinct value (No of Crimes) in Past and distinct name in a single query? means crime No also should unique and name is also uniqe. ...
My web application requires as little lag as possible. I have tried hosting it on a dedicated server, but users on the other side of world have complained about latency issues. So I am considering using CDN or Amazon services.... would either help resolve this? The application uses a lot of AJAX, so latency can be an issue. ...
I have a server application written in C++ and deployed in Cent OS. I haven't wrote any part of its code but i need to optimize its performance. Its current performance is acceptable for few amount of users but when the number of users increase the server's performance decrease dramatically. Are there any tools, techniques or best pract...
I have an event which I would like to have processed in a parallel manner. My idea is to make each callback be added to the ThreadPool, effectivley having each method that registered the event handled by the ThreadPool. My try-out code looks something like the following: Delegate[] delegates = myEvent.GetInvocationList(); IAsyncResult[...
Hi folks, Problem: I've got an ASP.NET website and i don't believe that my code is getting OutputCached correctly. I'm using IIS7 performance counters to show me the hits or misses a second. i've got a simple ASP.NET MVC website. I'm using the built in ASP.NET Output Cache magic. Here's some sample code :- [AcceptVerbs(HttpVerbs.Ge...
Hi guys: I've done some web based projects. In those days, I met a lot of difficulties(questions, confusions) and most of them can be figured out with help. But till now a really important question is still there, even with asking some experienced developers. The question is: When one functionality can be implemented with both server si...
I was using SortedList() in a class which stores about 15-100K data. Recently my requirements changed, data should not be stored as sorted any more so I switched to List(). However in this case I noticed that List() consumes about 20%+ more memory. 9K items: SortedList: 105MB List: 125MB 15K items: SortedList: 115MB List: 140...
Assume that we have 3 classes: Place, Contact, PhoneNumber classes. Under the Place class, I want to have a Contact class but it is better to keep PhoneNumber class under the Contact class. So in the Place class, it is more logical to reach the PhoneNumber by first getting the Contact object, then the PhoneNumber under the Contact obj...
Hi, With Java 1.6 out can we say that performance of Java 1.6 is almost equivalent to C++ code or still there is lot to improve on performance front in Java compared to C++ ? Thanks. ...
I currently believe that: When you need a structure from which you will be retrieving items randomly - use a HashMap When you will be retrieving items in order (e.g. using a for loop) - use an ArrayList Am I generally correct? Are there situations where this is not correct? ...
READ FIRST before answering! I have a RESTful service which wraps around the Entity Framework. Basically, all I did was create a database, add relations between the tables, create an Entity model around this database and finally expose the whole thing as a RESTful *.svc service. This is done, cannot be changed either. Now I need to que...
I have a view that pulls about 200 columns from a table, no joins. The procs that use the view only use about 10 columns from it. Does having the extra 190 columns have a significant impact on performance using the view? EDIT: Just to clarify based on original questioner's comment, the query in his proc only uses 10 columns out of 200. ...
I have a .NET 2.0 WinForms app that connects to a backend WAS server. I am using GZipStream to decode data coming back from a HttpWebRequest call made to the server. The data returned is compressed CSV, which Apache is compressing. The entire server stack is Hibernate-->EJB-->Spring-->Apache. For small responses, the performance is f...
We are getting ready to do a an initial deployment of an ASP.net MVC app on IIS 6 running on Windows Server 2003. We've been reading about performance issues involving the use of extenionless urls in MVC applications specifically in the case of removing the '.aspx' extension from the controller portion of the url. Has anyone who has dep...
I am trying to optimize a piece of .NET 2.0 C# code that looks like this: Dictionary<myType, string> myDictionary = new Dictionary<myType, string>(); // some other stuff // inside a loop check if key is there and if not add element if(!myDictionary.ContainsKey(currentKey)) { myDictionary.Add(currentKey, ""); } Looks like the Dictio...
I'm working with graphing accelerometer data here, and I'm trying to correct for gravity. To do this, I get the acceleration vector in spherical coordinates, decrease the radius by 1g, and convert back to cartesian. This method is called on a timer every 0.03 seconds: //poll accleration ThreeAxisAcceleration current = self.accelerationD...
Hello all, I am currrently making queries to my SQL Server using SQLCMD and I run this from PHPs exec() function. I was hoping to clarify that this isn't as efficient as the driver for SQL Server for PHP: http://www.microsoft.com/sqlserver/2005/en/us/PHP-Driver.aspx. I am not sure if this is the same as http://us3.php.net/manual/en/book...
quandry is - which of the following two method performs best Goal - get an object of type Wrapper ( defined below ) criteria - speed over storage no. of records - about 1000- about 2000, max about 6K Choices - Create Object on the fly or do a lookup from a dictionary Execution speed - called x times per second NB - i need to deliver t...
Is it possible to get a history of queries made in postgres? and is it be possible to get the time it took for each query? I'm currently trying to identify slow queries in the application I'm working on. I'm using Postgres 8.3.5 ...
I am running queries against an Oracle 10g with JDBC (using the latest drivers and UCP as DataSource) in order to retrieve CLOBs (avg. 20k characters). However the performance seems to be pretty bad: the batch retrieval of 100 LOBs takes 4s in average. The operation is also neither I/O nor CPU nor network bound judging from my observatio...