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  • HttpWebRequest is extremely slow!

    - by Earlz
    Hello, I am using an open source library to connect to my webserver. I was concerned that the webserver was going extremely slow and then I tried doing a simple test in Ruby and I got these results Ruby program: 2.11seconds for 100 HTTP GETs C# library: 20.81seconds for 100 HTTP GETs I have profiled and found the problem to be this function: private HttpWebResponse GetRawResponse(HttpWebRequest request) { HttpWebResponse raw = null; try { raw = (HttpWebResponse)request.GetResponse(); //This line! } catch (WebException ex) { if (ex.Response is HttpWebResponse) { raw = ex.Response as HttpWebResponse; } } return raw; } The marked line is takes over 1 second to complete by itself while the ruby program making 1 request takes .3 seconds. I am also doing all of these tests on 127.0.0.1, so network bandwidth is not an issue. What could be causing this huge slow down?

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  • Semantic Grid System, Media Query issue

    - by Andy
    I'm using the Semantic Grid System to build a responsive site. However, something isn't quite right with the media queries that should obviously kick in once it hits a particular screen size. I'll reference what i mean with their example on the website : if I view this on my iPhone for example, given that it is supposed to adjust to a single column structure on a mobile device, it still throws out the web version of the page. That is true for both Safari and Chrome on my iPhone. However, if I use the RWD bookmarklet to check it's appearance at different resolutions it appears as expected for the mobile resolution. Also, ironically, if I resize the page in Safari on my desktop it also adjusts accordingly once I get down to the approriate screen size, but not in Firefox. The media query that it uses once it hits 720px is @media screen and (max-width: 720px) { #maincolumn, #sidebar { .column(12); margin-bottom: 1em; } } and I might be wide of the mark here but I think that must be the issue. But given that this is directly from the semantic.gs website I'm not inclined to question their own code. Any idea what the problem might be?

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  • stopwatch accuracy

    - by oo
    How accurate is System.Diagnostics.Stopwatch? I am trying to do some metrics for different code paths and I need it to be exact. Should I be using stopwatch or is there another solution that is more accurate. I have been told that sometimes stopwatch gives incorrect information.

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  • NHibernate Projection Components

    - by reggieboyYEAH
    Hello guys im trying to hydrate a DTO using projections in NHibernate this is my code IList<PatientListViewModel> list = y.CreateCriteria<Patient>() .SetProjection(Projections.ProjectionList() .Add(Projections.Property("Birthdate"), "Birthdate") .Add(Projections.Property("Doctor.Id"), "DoctorId") .Add(Projections.Property("Gender"), "Gender") .Add(Projections.Property("Id"), "PatientId") .Add(Projections.Property("Patient.Name.Fullname"), "Fullname") ) .SetResultTransformer(Transformers.AliasToBean<PatientListViewModel>()) .List<PatientListViewModel>(); this code is throwing an exception? anyone know what is the problem? here is the error message Message: could not resolve property: Patient.Name.Fullname of: OneCare.Domain.Entities.Patient

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  • Using NHibernate's HQL to make a query with multiple inner joins

    - by Abu Dhabi
    The problem here consists of translating a statement written in LINQ to SQL syntax into the equivalent for NHibernate. The LINQ to SQL code looks like so: var whatevervar = from threads in context.THREADs join threadposts in context.THREADPOSTs on threads.thread_id equals threadposts.thread_id join posts1 in context.POSTs on threadposts.post_id equals posts1.post_id join users in context.USERs on posts1.user_id equals users.user_id orderby posts1.post_time where threads.thread_id == int.Parse(id) select new { threads.thread_topic, posts1.post_time, users.user_display_name, users.user_signature, users.user_avatar, posts1.post_body, posts1.post_topic }; It's essentially trying to grab a list of posts within a given forum thread. The best I've been able to come up with (with the help of the helpful users of this site) for NHibernate is: var whatevervar = session.CreateQuery("select t.Thread_topic, p.Post_time, " + "u.User_display_name, u.User_signature, " + "u.User_avatar, p.Post_body, p.Post_topic " + "from THREADPOST tp " + "inner join tp.Thread_ as t " + "inner join tp.Post_ as p " + "inner join p.User_ as u " + "where tp.Thread_ = :what") .SetParameter<THREAD>("what", threadid) .SetResultTransformer(Transformers.AliasToBean(typeof(MyDTO))) .List<MyDTO>(); But that doesn't parse well, complaining that the aliases for the joined tables are null references. MyDTO is a custom type for the output: public class MyDTO { public string thread_topic { get; set; } public DateTime post_time { get; set; } public string user_display_name { get; set; } public string user_signature { get; set; } public string user_avatar { get; set; } public string post_topic { get; set; } public string post_body { get; set; } } I'm out of ideas, and while doing this by direct SQL query is possible, I'd like to do it properly, without defeating the purpose of using an ORM. Thanks in advance!

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  • Database INSERT does not take place

    - by reggie
    My code is as follows: <?php include("config.php"); $ip=$_SERVER['REMOTE_ADDR']; if($_POST['id']) { $id=$_POST['id']; $id = mysql_escape_String($id); $ip_sql=mysql_query("select ip_add from Voting_IP where mes_id_fk='$id' and ip_add='$ip'"); $count=mysql_num_rows($ip_sql); if($count==0) { $sql = "update Messages set up=up+1 where mes_id='$id'"; mysql_query($sql); $sql_in = "insert into Voting_IP (mes_id_fk,ip_add) values ('$id','$ip')"; mysql_query($sql_in) or die(mysql_error()); echo "<script>alert('Thanks for the vote');</script>"; } else { echo "<script>alert('You have already voted');</script>"; } $result=mysql_query("select up from Messages where mes_id='$id'"); $row=mysql_fetch_array($result); $up_value=$row['up']; echo "<img src='button.png' width='110' height='90'>"; echo $up_value; } ?> My problem is that the insert process does not take place at all. The script tags echos an alert box. Even the img tag is echoed to the web page. But the insert process does not take place. The config file is fine. Note: This code works on my local machine which has PHP 5.3 but it does not work on the server which has PHP 5.2. Any advice?

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  • Why does appending "" to a String save memory?

    - by hsmit
    I used a variable with a lot of data in it, say String data. I wanted to use a small part of this string in the following way: this.smallpart = data.substring(12,18); After some hours of debugging (with a memory visualizer) I found out that the objects field smallpart remembered all the data from data, although it only contained the substring. When I changed the code into: this.smallpart = data.substring(12,18)+""; ..the problem was solved! Now my application uses very little memory now! How is that possible? Can anyone explain this? I think this.smallpart kept referencing towards data, but why? UPDATE: How can I clear the big String then? Will data = new String(data.substring(0,100)) do the thing?

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  • LINQ - How to query a range of effective dates that only has start dates

    - by itchi
    I'm using C# 3.5 and EntityFramework. I have a list of items in the database that contain interest rates. Unfortunately this list only contains the Effective Start Date. I need to query this list for all items within a range. However, I can't see a way to do this without querying the database twice. (Although I'm wondering if delayed execution with EntityFramework is making only one call.) Regardless, I'm wondering if I can do this without using my context twice. internal IQueryable<Interest> GetInterests(DateTime startDate, DateTime endDate) { var FirstDate = Context.All().Where(x => x.START_DATE < startDate).Max(x => x.START_DATE); IQueryable<Interest> listOfItems = Context.All().Where(x => x.START_DATE >= FirstDate && x.START_DATE <= endDate); return listOfItems; }

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  • Can MySQL Nested Select return list of results

    - by John
    Hi I want to write a mysql statement which will return a list of results from one table along with a comma separated list of field from another table. I think an example might better explain it Table 1 ======================== id First_Name Surname ---------------------- 1 Joe Bloggs 2 Mike Smith 3 Jane Doe Table 2 ======================== id Person_Id Job_id --------------------- 1 1 1 2 1 2 3 2 2 4 3 3 5 3 4 I want to return a list of people with a comma separated list of job_ids. So my result set would be id First_Name Surname job_id ------------------------------ 1 Joe Bloggs 1,2 2 Mike Smith 2 3 Jane Doe 3,4 I guess the sql would be something like select id, First_Name, Surname, (SELECT job_id FROM Table 2) as job_id from Table 1 but obviously this does not work so need to change the '(SELECT job_id FROM Table 2) as job_id' part. Hope this makes sense Thanks John

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  • How do I make "simple" throughput servlet-filter?

    - by Tommy
    I'm looking to create a filter that can give me two things: number of request pr minute, and average responsetime pr minute. I already got the individual readings, I'm just not sure how to add them up. My filter captures every request, and it records the time each request takes: public void doFilter(ServletRequest request, ...() { long start = System.currentTimeMillis(); chain.doFilter(request, response); long stop = System.currentTimeMillis(); String time = Util.getTimeDifferenceInSec(start, stop); } This information will be used to create some pretty Google Chart charts. I don't want to store the data in any database. Just a way to get current numbers out when requested As this is a high volume application; low overhead is essential. I'm assuming my applicationserver doesn't provide this information.

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  • How to speed up marching cubes?

    - by Dan Vinton
    I'm using this marching cube algorithm to draw 3D isosurfaces (ported into C#, outputting MeshGeomtry3Ds, but otherwise the same). The resulting surfaces look great, but are taking a long time to calculate. Are there any ways to speed up marching cubes? The most obvious one is to simply reduce the spatial sampling rate, but this reduces the quality of the resulting mesh. I'd like to avoid this. I'm considering a two-pass system, where the first pass samples space much more coarsely, eliminating volumes where the field strength is well below my isolevel. Is this wise? What are the pitfalls? Edit: the code has been profiled, and the bulk of CPU time is split between the marching cubes routine itself and the field strength calculation for each grid cell corner. The field calculations are beyond my control, so speeding up the cubes routine is my only option... I'm still drawn to the idea of trying to eliminate dead space, since this would reduce the number of calls to both systems considerably.

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  • database design to speed up hibernate querying of large dataset

    - by paddydub
    I currently have the below tables representing a bus network mapped in hibernate, accessed from a Spring MVC based bus route planner I'm trying to make my route planner application perform faster, I load all the above tables into Lists to perform the route planner logic. I would appreciate if anyone has any ideas of how to speed my performace Or any suggestions of another method to approach this problem of handling a large set of data Coordinate Connections Table (INT,INT,INT)( Containing 50,000 Coordinate Connections) ID, FROMCOORDID, TOCOORDID 1 1 2 2 1 17 3 1 63 4 1 64 5 1 65 6 1 95 Coordinate Table (INT,DECIMAL, DECIMAL) (Containing 4700 Coordinates) ID , LAT, LNG 0 59.352669 -7.264341 1 59.352669 -7.264341 2 59.350012 -7.260653 3 59.337585 -7.189798 4 59.339221 -7.193582 5 59.341408 -7.205888 Bus Stop Table (INT, INT, INT)(Containing 15000 Stops) StopID RouteID COORDINATEID 1000100001 100 17 1000100002 100 18 1000100003 100 19 1000100004 100 20 1000100005 100 21 1000100006 100 22 1000100007 100 23 This is how long it takes to load all the data from each table: stop.findAll = 148ms, stops.size: 15670 Hibernate: select coordinate0_.COORDINATEID as COORDINA1_2_, coordinate0_.LAT as LAT2_, coordinate0_.LNG as LNG2_ from COORDINATES coordinate0_ coord.findAll = 51ms , coordinates.size: 4704 Hibernate: select coordconne0_.COORDCONNECTIONID as COORDCON1_3_, coordconne0_.DISTANCE as DISTANCE3_, coordconne0_.FROMCOORDID as FROMCOOR3_3_, coordconne0_.TOCOORDID as TOCOORDID3_ from COORDCONNECTIONS coordconne0_ coordinateConnectionDao.findAll = 238ms ; coordConnectioninates.size:48132 Hibernate Annotations @Entity @Table(name = "STOPS") public class Stop implements Serializable { @Id @GeneratedValue @Column(name = "COORDINATEID") private Integer CoordinateID; @Column(name = "LAT") private double latitude; @Column(name = "LNG") private double longitude; } @Table(name = "COORDINATES") public class Coordinate { @Id @GeneratedValue @Column(name = "COORDINATEID") private Integer CoordinateID; @Column(name = "LAT") private double latitude; @Column(name = "LNG") private double longitude; } @Entity @Table(name = "COORDCONNECTIONS") public class CoordConnection { @Id @GeneratedValue @Column(name = "COORDCONNECTIONID") private Integer CoordinateID; /** * From Coordinate_id value */ @Column(name = "FROMCOORDID", nullable = false) private int fromCoordID; /** * To Coordinate_id value */ @Column(name = "TOCOORDID", nullable = false) private int toCoordID; //private Coordinate toCoordID; }

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  • Linux 2.6.31 Scheduler and Multithreaded Jobs

    - by dsimcha
    I run massively parallel scientific computing jobs on a shared Linux computer with 24 cores. Most of the time my jobs are capable of scaling to 24 cores when nothing else is running on this computer. However, it seems like when even one single-threaded job that isn't mine is running, my 24-thread jobs (which I set for high nice values) only manage to get ~1800% CPU (using Linux notation). Meanwhile, about 500% of the CPU cycles (again, using Linux notation) are idle. Can anyone explain this behavior and what I can do about it to get all of the 23 cores that aren't being used by someone else? Notes: In case it's relevant, I have observed this on slightly different kernel versions, though I can't remember which off the top of my head. The CPU architecture is x64. Is it at all possible that the fact that my 24-core jobs are 32-bit and the other jobs I'm competing w/ are 64-bit is relevant? Edit: One thing I just noticed is that going up to 30 threads seems to alleviate the problem to some degree. It gets me up to ~2100% CPU.

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  • showing null rows using join

    - by Pradyut Bhattacharya
    Hi, In mysql i m selecting from a table shouts having a foreign key to another table named "roleuser" with the matching column as user_id Now the user_id column in the shouts table for some rows is null (not actually null but with no inserts in mysql) How to show all the rows of the shouts table either with user_id null or not I m executing the sql statement SELECT s.*, r.firstname, r.lastname FROM shouts s left join roleuser r where r.user_id = s.user_id limit 50; which does not executes and shows You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'where r.user_id = s.user_id limit 50' at line 2 but using inner join the sql executes which shows rows which only have user_id values in the shouts table. the nulls are not shown. SELECT s.*, r.firstname, r.lastname FROM shouts s inner join roleuser r where r.user_id = s.user_id limit 50; How can i show all the rows from the shouts table and null values in the firstname and lastname columns where the user_id is null in the shouts table. If not at all possible with sql may be using stored procedures... Thanks Pradyut

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  • how to select the min value using having key word

    - by LOVE_KING
    I have created the table stu_dep_det CREATE TABLE `stu_dept_cs` ( `s_d_id` int(10) unsigned NOT NULL auto_increment, `stu_name` varchar(15) , `gender` varchar(15) , `address` varchar(15),`reg_no` int(10) , `ex_no` varchar(10) , `mark1` varchar(10) , `mark2` varchar(15) , `mark3` varchar(15) , `total` varchar(15) , `avg` double(2,0), PRIMARY KEY (`s_d_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC AUTO_INCREMENT=8 ; then Inserted the values INSERT INTO `stu_dept_cs` (`s_d_id`, `stu_name`, `gender`, `address`, `reg_no`, `ex_no`, `mark1`, `mark2`, `mark3`, `total`, `avg`) VALUES (1, 'alex', 'm', 'chennai', 5001, 's1', '70', '90', '95', '255', 85), (2, 'peter', 'm', 'chennai', 5002, 's1', '80', '70', '90', '240', 80), (6, 'parv', 'f', 'mumbai', 5003, 's1', '88', '60', '80', '228', 76), (7, 'basu', 'm', 'kolkatta', 5004, 's1', '85', '95', '56', '236', 79); I want to select the min(avg) using having keyword and I have used the following sql statement SELECT * FROM stu_dept_cs s having min(avg) Is it correct or not plz write the correct ans....

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  • Is it possible to disable user sessions for guest in Joomla 1.5

    - by WebolizeR
    Hi; Is it possible to disable session handling in Joomla 1.5 for guests. I donot use user system in the frontend, i assumed that it's not needed to run queries like below: Site will use APC or Memcache as caching system under heavy load, so it's important for me tHanks for your comments # DELETE FROM jos_session WHERE ( time < '1274709357' ) # SELECT * FROM jos_session WHERE session_id = '70c247cde8dcc4dad1ce111991772475' # UPDATE jos_session SET time='1274710257',userid='0',usertype='',username='',gid='0',guest='1',client_id='0',data='__default|a:8:{s:15:\"session.counter\";i:5;s:19:\"session.timer.start\";i:1274709740;s:18:\"session.timer.last\";i:1274709749;s:17:\"session.timer.now\";i:1274709754;s:22:\"session.client.browser\";s:88:\"Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3\";s:8:\"registry\";O:9:\"JRegistry\":3:{s:17:\"_defaultNameSpace\";s:7:\"session\";s:9:\"_registry\";a:1:{s:7:\"session\";a:1:{s:4:\"data\";O:8:\"stdClass\":0:{}}}s:7:\"_errors\";a:0:{}}s:4:\"user\";O:5:\"JUser\":19:{s:2:\"id\";i:0;s:4:\"name\";N;s:8:\"username\";N;s:5:\"email\";N;s:8:\"password\";N;s:14:\"password_clear\";s:0:\"\";s:8:\"usertype\";N;s:5:\"block\";N;s:9:\"sendEmail\";i:0;s:3:\"gid\";i:0;s:12:\"registerDate\";N;s:13:\"lastvisitDate\";N;s:10:\"activation\";N;s:6:\"params\";N;s:3:\"aid\";i:0;s:5:\"guest\";i:1;s:7:\"_params\";O:10:\"JParameter\":7:{s:4:\"_raw\";s:0:\"\";s:4:\"_xml\";N;s:9:\"_elements\";a:0:{}s:12:\"_elementPath\";a:1:{i:0;s:74:\"C:\xampp\htdocs\sites\iv.mynet.com\libraries\joomla\html\parameter\element\";}s:17:\"_defaultNameSpace\";s:8:\"_default\";s:9:\"_registry\";a:1:{s:8:\"_default\";a:1:{s:4:\"data\";O:8:\"stdClass\":0:{}}}s:7:\"_errors\";a:0:{}}s:9:\"_errorMsg\";N;s:7:\"_errors\";a:0:{}}s:13:\"session.token\";s:32:\"a2b19c7baf223ad5fd2d5503e18ed323\";}' WHERE session_id='70c247cde8dcc4dad1ce111991772475'

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  • Retrieving many huge sized EPS files and converting them to JPEG in ASP.NET application

    - by Ashish Gupta
    I have many (600) EPS files(300 KB - 1 MB) in database. In my ASP.NET application (using ASP.NET 4.0) I need to retrieve them one by one and call a web service which would convert the content to the JPEG file and update the database (JPEGContent column with the JPEG content). However, retrieving the content for 600 of them itself takes too long from the SQL management studio itself (takes 5 minutes for 10 EPS contents). So I have two issues:- 1) How to get the EPS content ( unfortunately, selecting certain number of content is not an option :-( ):- Approach 1:- foreach(var DataRow in DataTable.Rows) { // get the Id and byte[] of EPS // Call the web method to convert EPS content to JPEG which would also update the database. } or foreach(var DataRow in DataTable.Rows) { // get only the Id of EPS // Hit database to get the content of EPS // Call the web method to convert EPS content to JPEG which would also update the database. } or Any other approach? 2) Converting EPS to JPEG using a web method for 600 contents. Ofcourse, each call would be a long running operation. Would task parellel library (TPL) be a better way to achieve this? Also, is doing the entire thing in a SQL CLR function a good idea?

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  • When should I open and close a website's cached WCF proxy?

    - by Brandon Linton
    I've browsed around the other articles on StackOverflow that relate to caching WCF proxies for reuse, and I've read this article explaining why I should explicitly open the proxy before calling anything on it. I'm still a little hazy on the best implementation details. My question is: when should I open and close proxies for service calls on a website, and what should their lifetime be (per call, per request, or per web app)? We aren't planning on leveraging cached security contexts at the moment (but it's not unforeseeable). Thanks!

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  • How can I update multiple columns with a Replace in SQL server?

    - by Kettenbach
    How do I update different columns and rows across a table? I want to do something similiar to replace a string in SQL server I want to do this but the value exists in multiple columns of the same type. The values are foreign keys varchars to an employee table. Each column represents a task, so the same employee may be assigned to several tasks in a record and those tasks will vary between records. How can I do this effectively? Basically something of a replace all accross varying columns throughout a table. Thanks for any help or advice. Cheers, ~ck in San Diego

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  • How to efficiently save changes made in UI/main thread with Core Data?

    - by Jaanus
    So, there have been several posts here about importing and saving data from an external data source into Core Data. Apple documents a reasonable pattern for this: "import and save on background thread, merge saved objects to main thread." All fine and good. I have a related but different problem: the user is modifying data in the UI and main thread, and thus modifies state of some objects in the managed object context (MOC). I would like to save these changes from time to time. What is a good way to do that? Now, you could say that I could do the same: create a background thread with its own MOC and pass the changed objectID-s there. The catch-22 for me with this is that an object's ID changes when it is saved, and I cannot guarantee the order of things happening. I may end up passing a different objectID into the background thread for the same object, based on whether the object has been previously saved or not, and I don't know if Core Data can resolve this and see that different objectID-s are pointing to the same object and not create duplicates for me. (I could test this, but I'm lazywebbing with this question first.) One thought I had: I could always do MOC saves on a background thread, and queue them up with operationqueue, so that there is always only one save in progress. I would not create a new MOC, I would just use the same MOC as in main thread. Now, this is not thread safe and when someone modifies the MOC in main thread while it is being saved in background thread, the results will probably be catastrophic. But, minus the thread safety, you can see what kind of solution I'd wish for. To be clear, the problem I need to fix is that if I just do the save in main thread, it blocks the UI for an unacceptably long period of time, I want to move the save to background thread. So, questions: what about the reasoning of an object ID changing during saving, and Core Data being able to resolve them to the same object? Would this be the right way of addressing this problem? any other good ways of doing this?

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  • Python: Why is IDLE so slow?

    - by Adam Matan
    Hi, IDLE is my favorite Python editor. It offers very nice and intuitive Python shell which is extremely useful for unit-testing and debugging, and a neat debugger. However, code executed under IDLE is insanely slow. By insanely I mean 3 orders of magnitude slow: bash time echo "for i in range(10000): print 'x'," | python Takes 0.052s, IDLE import datetime start=datetime.datetime.now() for i in range(10000): print 'x', end=datetime.datetime.now() print end-start Takes: >>> 0:01:44.853951 Which is roughly 2,000 times slower. Any thoughts, or ideas how to improve this? I guess it has something to do with the debugger in the background, but I'm not really sure. Adam

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  • High CPU Usage with WebGL?

    - by shoosh
    I'm checking out the nightly builds of Firefox and Chromium with support of WebGL with a few demos and tutorials and I can't help but wonder about the extremely high CPU load they cause. A simple demo like this one runs at a sustained 60% of my dual core. The large version of this one maxes out the CPU to 100% and has some visible frame loss. Chromium seems to be slightly better than firefox but not by much. I'm pretty sure that if these were desktop application the CPU load would be negligible. So what's going on here? what is it doing? Running the simple scripts of these can't be that demanding. Is it the extra layer of security or something?

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  • The "first past the post election" query problem

    - by MPelletier
    This problem may seem like school work, but it isn't. At best it is self-imposed school work. I encourage any teachers to take is as an example if they wish. "First past the post" elections are single-round, meaning that whoever gets the most votes win, no second rounds. Suppose a table for an election. CREATE TABLE ElectionResults ( DistrictHnd INTEGER NOT NULL, PartyHnd INTEGER NOT NULL, CandidateName VARCHAR2(100) NOT NULL, TotalVotes INTEGER NOT NULL, PRIMARY KEY DistrictHnd, PartyHnd); The table has two foreign keys: DistrictHnd points to a District table (lists all the different electoral districts) and PartyHnd points to a Party table (lists all the different political parties). I won't bother with other tables here, joining them is trivial. This is just a wee bit of context. The question: What SQL query will return a table listing the DistrictHnd, PartyHnd, CandidateName and TotalVotes of the winners (max votes) in each District? This does not suppose any particular database system. If you wish to stick to a particular implementation of SQL, go the way of SQLite and MySQL. If you can devise a better schema (or an easier one), that is acceptable too. Criteria: simplicity, portability to other databases.

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  • Indexing only one MySQL column value

    - by BrainCore
    I have a MySQL InnoDB table with a status column. The status can be 'done' or 'processing'. As the table grows, at most .1% of the status values will be 'processing,' whereas the other 99.9% of the values will be 'done.' This seems like a great candidate for an index due to the high selectivity for 'processing' (though not for 'done'). Is it possible to create an index for the status column that only indexes the value 'processing'? I do not want the index to waste an enormous amount of space indexing 'done.'

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