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• Populating PDF Fields using FDFACX

  - by NWilliams

  I was recently asked to preform some updates to an existing PDF document. The changes required were completed using Adobe Designer (the only tool I have available to me). These changes included alignment, and new text. Note that there were fillable form fields on the forms, and they were left untouched. The saved version of the form was then put into our ASP.NET application, which pre-populates the form fields were applicable (things like name, address etc... things we have in our database). For some reason, the new form does not populate. I've confirmed that the form fields have the correct names, that the actual file (the pdf) that is being pre-populated has the same permissions as others that are working. There are no errors thrown, and no difference in a step through with a working form and a non-working form. This is a legacy project and I have no real experience with the PDF populator they are using ... FDFACX .NET? And can't find a lot of info on it online. Any ideas?

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• Connection Pool Strategy: Good, Bad or Ugly?

  - by Drew

  I'm in charge of developing and maintaining a group of Web Applications that are centered around similar data. The architecture I decided on at the time was that each application would have their own database and web-root application. Each application maintains a connection pool to its own database and a central database for shared data (logins, etc.) A co-worker has been positing that this strategy will not scale because having so many different connection pools will not be scalable and that we should refactor the database so that all of the different applications use a single central database and that any modifications that may be unique to a system will need to be reflected from that one database and then use a single pool powered by Tomcat. He has posited that there is a lot of "meta data" that goes back and forth across the network to maintain a connection pool. My understanding is that with proper tuning to use only as many connections as necessary across the different pools (low volume apps getting less connections, high volume apps getting more, etc.) that the number of pools doesn't matter compared to the number of connections or more formally that the difference in overhead required to maintain 3 pools of 10 connections is negligible compared to 1 pool of 30 connections. The reasoning behind initially breaking the systems into a one-app-one-database design was that there are likely going to be differences between the apps and that each system could make modifications on the schema as needed. Similarly, it eliminated the possibility of system data bleeding through to other apps. Unfortunately there is not strong leadership in the company to make a hard decision. Although my co-worker is backing up his worries only with vagueness, I want to make sure I understand the ramifications of multiple small databases/connections versus one large database/connection pool.

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• Faster Insertion of Records into a Table with SQLAlchemy

  - by Kyle Brandt

  I am parsing a log and inserting it into either MySQL or SQLite using SQLAlchemy and Python. Right now I open a connection to the DB, and as I loop over each line, I insert it after it is parsed (This is just one big table right now, not very experienced with SQL). I then close the connection when the loop is done. The summarized code is: log_table = schema.Table('log_table', metadata, schema.Column('id', types.Integer, primary_key=True), schema.Column('time', types.DateTime), schema.Column('ip', types.String(length=15)) .... engine = create_engine(...) metadata.bind = engine connection = engine.connect() .... for line in file_to_parse: m = line_regex.match(line) if m: fields = m.groupdict() pythonified = pythoninfy_log(fields) #Turn them into ints, datatimes, etc if use_sql: ins = log_table.insert(values=pythonified) connection.execute(ins) parsed += 1 My two questions are: Is there a way to speed up the inserts within this basic framework? Maybe have a Queue of inserts and some insertion threads, some sort of bulk inserts, etc? When I used MySQL, for about ~1.2 million records the insert time was 15 minutes. With SQLite, the insert time was a little over an hour. Does that time difference between the db engines seem about right, or does it mean I am doing something very wrong?

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• SQL Compact performance on device

  - by Ben M

  My SQL Compact database is very simple, with just three tables and a single index on one of the tables (the table with 200k rows; the other two have less than a hundred each). The first time the .sdf file is used by my Compact Framework application on the target Windows Mobile device, the system hangs for well over a minute while "something" is done to the database: when deployed, the DB is 17 megabytes, and after this first usage, it balloons to 24 megs. All subsequent usage is pretty fast, so I'm assuming there's some sort of initialization / index building going on during this first usage. I'd rather not subject the user to this delay, so I'm wondering what this initialization process is and whether it can be performed before deployment. For now, I've copied the "initialized" database back to my desktop for use in the setup project, but I'd really like to have a better answer / solution. I've tried "full compact / repair" in the VS Database Properties dialog, but this made no difference. Any ideas? For the record, I should add that the database is only read from by the device application -- no modifications are made by that code.

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• What are the Limitations for Connecting to an Access Query in Excel

  - by thornomad

  I have an Access 2007 database that has a number of tables, some are fairly large (100,000+ records); I have created a union query to pull some of the same types of data from multiple tables into one large query for pivot table manipulation and reporting. For example: SELECT Language FROM Table1 UNION ALL SELECT Language FROM Table2 UNION ALL SELECT Language FROM Table3; This works. I found, quickly, however, that a union query will not show up when connecting to the datasource from Excel 2007. So, I created a second query to reference the union query. Like so: SELECT * FROM [The Above Union Query]; This query works and it, initially, was accessible from Excel. Time passed, I've added more data. Suddenly, when I connect to my Access database from Excel my query referencing the union has disappeared. MS Access shows no signs of an issue (data displays in Access) and my other non-union queries are showing up in Excel 2007 ... but not the one that references the union. What could be going on? Why did it disappear? I noticed if I switch some of the referenced tables in the union query to a smaller table (with less rows) all of sudden the query appears in Excel again. At least, I think that's what the difference is. I really can't put my finger on why some of the union queries won't show up and some will. Am stumped and need some guidance. Thanks.

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• What /else/ causes this?

  - by Mordachai

  MFC Toolbox Library.lib(SimpleFileIO.obj) : error LNK2005: _wcsnlen already defined in libcmtd.lib(wcslen_s.obj) fatal error LNK1169: one or more multiply defined symbols found This is driving me nuts. Normally, one would get this if the various projects that are a part of their solution do not agree on which CRT to use (single threaded, multi-threaded, release or debug). However, I have been over this thing about 500 times now, and they all agree. Background: this is a VS 2010 project just converted from VS 2008. MFC Toolbox Library.lib is set to compile as a static library, using /MTd, as is the target .exe I am trying to compile in this solution. Further, the solution that this is being converted from (VS 2008) already compiles & links properly!!! So it's not like that there is a disagreement between the two .vcproj's - or at least there wasn't before the conversion. Furthermore, the MFC Toolbox Library is used by about 25 other projects in another solution - and in that solution (Master Build English) it compiles & links against those other projects without complaint in both debug and release targets. I have just spent the last hour going over every single project property for this target project (Cimex Header Viewer) vs. several different target exe projects in Master Build English solution - and I cannot find a difference. They appear to be identical, excepting that they're different names. I've tried doing a clean & build all. I'm simply out of ideas. Does anyone have a thought on what else I might investigate??? I think I'm ready to start chewing glass. :(

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• Where are possible locations of queueing/buffering delays in Linux multicast?

  - by Matt

  We make heavy use of multicasting messaging across many Linux servers on a LAN. We are seeing a lot of delays. We basically send an enormous number of small packages. We are more concerned with latency than throughput. The machines are all modern, multi-core (at least four, generally eight, 16 if you count hyperthreading) machines, always with a load of 2.0 or less, usually with a load less than 1.0. The networking hardware is also under 50% capacity. The delays we see look like queueing delays: the packets will quickly start increasing in latency, until it looks like they jam up, then return back to normal. The messaging structure is basically this: in the "sending thread", pull messages from a queue, add a timestamp (using gettimeofday()), then call send(). The receiving program receives the message, timestamps the receive time, and pushes it in a queue. In a separate thread, the queue is processed, analyzing the difference between sending and receiving timestamps. (Note that our internal queues are not part of the problem, since the timestamps are added outside of our internal queuing.) We don't really know where to start looking for an answer to this problem. We're not familiar with Linux internals. Our suspicion is that the kernel is queuing or buffering the packets, either on the send side or the receive side (or both). But we don't know how to track this down and trace it. For what it's worth, we're using CentOS 4.x (RHEL kernel 2.6.9).

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• Rationale of C# iterators design (comparing to C++)

  - by macias

  I found similar topic: http://stackoverflow.com/questions/56347/iterators-in-c-stl-vs-java-is-there-a-conceptual-difference Which basically deals with Java iterator (which is similar to C#) being unable to going backward. So here I would like to focus on limits -- in C++ iterator does not know its limit, you have by yourself compare the given iterator with the limit. In C# iterator knows more -- you can tell without comparing to any external reference, if the iterator is valid or not. I prefer C++ way, because once having iterator you can set any iterator as a limit. In other words if you would like to get only few elements instead of entire collection, you don't have to alter the iterator (in C++). For me it is more "pure" (clear). But of course MS knew this and C++ while designing C#. So what are the advantages of C# way? Which approach is more powerful (which leads to more elegant functions based on iterators). What do I miss? If you have thoughts on C# vs. C++ iterators design other than their limits (boundaries), please also answer. Note: (just in case) please, keep the discussion strictly technical. No C++/C# flamewar.

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• Margically appearing margin in footer. Could use some fresh eye's on this.

  - by Banderdash

  Hi chaps! Got a nearly finished coded comp here: http://clients.pixelbleed.net/biodesign/ I realize it's not completely valid, what with my nesting of li's and ul's within A tags. Unfortunately that's the way it has to be. My issue is with the very bottom of the footer. It has a space showing the body's background color beneath it. Tried a number of things and this space after the black link bar on the very bottom is a resistant little bugger. Ideally the black box on the bottom should rest against the very base of the view-port, at least when the content is sufficiently long--which it is in this case. If someone would like to take a quick peak at my source and give me some ideas I'd be very grateful. The CSS can be found here: http://clients.pixelbleed.net/biodesign/css/core.css And, yes, I've tried removing the height:100%. Makes no difference it seems. I do believe the issue to be with the footer, as when I remove these Div's the content rests as it should. Just don't see anything in my CSS to cause the margin/spacing issue though. Thanks so much.

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• is it better to query database or grab from file? php & mysql

  - by pfunc

  I am keeping a large amount of words in a database that I want to match up articles to. I was thinking that it would just be better to keep these words in an array and grab that array whenever needed instead of querying the database every time (since the words won't be changing that much). Is there much performance difference in doing this? And if I were to do this, how to I write a script that writes the array to a a new php file. I tried writing the array like so: while( $row = mysql_fetch_assoc($query)) { $newArray[] = $row; } $fp = fopen('noWordsArr.php', 'w'); fwrite($fp, $newArray); fclose($fp); But all I get in the other file is "Array". So i figured I could write this and then write have a chron hit up the file every few days or so in case things have changed. But I guess if there is no performance advantage then it prob won't be necessary and I can just query the database every time I need to access the words.

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• what use does the javascript for each method have (that map can't do)?

  - by JohnMerlino

  Hey all, The only difference I see in map and foreach is that map is returning an array and foreach is not. However, I don't even understand the last line of the foreach method "func.call(scope, this[i], i, this);". For example, isn't "this" and "scope" referring to same object and isn't this[i] and i referring to the current value in the loop? I noticed on another post someone said "Use forEach when you want to do something on the basis of each element of the list. You might be adding things to the page, for example. Essentially, it's great for when you want "side effects". I don't know what is meant by side effects. Array.prototype.map = function(fnc) { var a = new Array(this.length); for (var i = 0; i < this.length; i++) { a[i] = fnc(this[i]); } return a; } Array.prototype.forEach = function(func, scope) { scope = scope || this; for (var i = 0, l = this.length; i < l; i++) func.call(scope, this[i], i, this); } Finally, are there any real uses for these methods in javascript (since we aren't updating a database) other than to manipulate numbers like this: alert([1,2,3,4].map(function(x){ return x + 1})); //this is the only example I ever see of map in javascript. Thanks for any reply.

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• C++ Array vs vector

  - by blue_river

  when using C++ vector, time spent is 718 milliseconds, while when I use Array, time is almost 0 milliseconds. Why so much performance difference? int _tmain(int argc, _TCHAR* argv[]) { const int size = 10000; clock_t start, end; start = clock(); vector<int> v(size*size); for(int i = 0; i < size; i++) { for(int j = 0; j < size; j++) { v[i*size+j] = 1; } } end = clock(); cout<< (end - start) <<" milliseconds."<<endl; // 718 milliseconds int f = 0; start = clock(); int arr[size*size]; for(int i = 0; i < size; i++) { for(int j = 0; j < size; j++) { arr[i*size+j] = 1; } } end = clock(); cout<< ( end - start) <<" milliseconds."<<endl; // 0 milliseconds return 0; }

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• Make password case unsensitive in shared ASP.Net membership tables web ap

  - by bill

  Hi all, i have two webapps.. that share ASP.Net membership tables. Everything works fine except i cannot remove case-sensitivity in one of the apps the way i am doing it in the other. in the non-working app void Login1_LoggingIn(object sender, LoginCancelEventArgs e) { string username = Login1.UserName.Trim(); if (!string.IsNullOrEmpty(username)) { MembershipUser user = Membership.GetUser(username); if (user != null) { // Only adjust the UserName if the password is correct. This is more secure // so a hacker can't find valid usernames if we adjust the case of mis-cased // usernames with incorrect passwords. string password = Login1.Password.ToUpper(); if (Membership.ValidateUser(user.UserName, password)) { Login1.UserName = user.UserName; } } } } is not working. the password is stored as all upper case. Converted at the time the membership user is created! So if the password is PASSWORD, typing PASSWORD allows me to authenticate. but typing password does not! Even though i can see the string being sent is PASSWORD (converted with toUpper()). I am at a complete loss on this.. in the other app i can type in lower or upper or mixed and i am able to authenticate. In the other app i am not using the textboxes from the login control though.. not sure if this is making the difference??

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• Legacy application creates dialogs in non-ui thread.

  - by Frater

  I've been working support for a while on a legacy application and I've noticed a bit of a problem. The system is an incredibly complex client/server with standard and custom frameworks. One of the custom frameworks built into the application involves validating workflow actions. It finds potential errors, separates them into warnings and errors, and passes the results back to the client. The main difference between warnings and errors is that warnings ask the user if they wish to ignore the error. The issue I have is that the dialog for this prompt is created on a non-ui thread, and thus we get cross-threading issues when the dialog is shown. I have attempted to invoke the showing of the dialog, however this fails because the window handle has not been created. (InvokeRequired returns false, which I assume in this case means it cannot find a decent handle in its parent tree, rather than that it doesn't require it.) Does anyone have any suggestions for how I can create this dialog and get the UI thread to set it up and call it?

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• Noise with multi-threaded raytracer

  - by herber88

  This is my first multi-threaded implementation, so it's probably a beginners mistake. The threads handle the rendering of every second row of pixels (so all rendering is handled within each thread). The problem persists if the threads render the upper and lower parts of the screen respectively. Both threads read from the same variables, can this cause any problems? From what I've understood only writing can cause concurrency problems... Can calling the same functions cause any concurrency problems? And again, from what I've understood this shouldn't be a problem... The only time both threads write to the same variable is when saving the calculated pixel color. This is stored in an array, but they never write to the same indices in that array. Can this cause a problem? Multi-threaded rendered image (Spam prevention stops me from posting images directly..) Ps. I use the exactly same implementation in both cases, the ONLY difference is a single vs. two threads created for the rendering.

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• What is a mantainable way of saving "star rating" in a database?

  - by Montecristo

  I'll use the jQuery plugin for presenting the user with a nice interface The request is to display 5 stars, up to a total score of 10 (2 points per star). By now I thought about using 7/10 as a format for that value, but what if at some point in the future I'll receive a request like We would like to give users more choice, let's increase the total score to 20 (so that each star contributes with a maximum of 4 points) I'll end up with a table with mixed values for the "star rating" column: some will be like 7/10 while others will be like 14/20. Is it ok for you to have this difference in the database and deal with it in the logic layer to have it consistent? Or is preferred another way so that querying the table will not result in inconsistent results outside the application? Maybe floating point values could help me, is it better to store that value as a number less than or equal to one? So in each of the two examples the resulting value stored in the database would be 0,7, as a number, not a varchar, which can be queried also outside the application. What do you think?

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• Does breaking chained Select()s in LINQ to objects hurt performance?

  - by Justin

  Take the following pseudo C# code: using System; using System.Data; using System.Linq; using System.Collections.Generic; public IEnumerable<IDataRecord> GetRecords(string sql) { // DB logic goes here } public IEnumerable<IEmployer> Employers() { string sql = "select EmployerID from employer"; var ids = GetRecords(sql).Select(record => (record["EmployerID"] as int?) ?? 0); return ids.Select(employerID => new Employer(employerID) as IEmployer); } Would it be faster if the two Select() calls were combined? Is there an extra iteration in the code above? Is the following code faster? public IEnumerable<IEmployer> Employers() { string sql = "select EmployerID from employer"; return Query.Records(sql).Select(record => new Employer((record["EmployerID"] as int?) ?? 0) as IEmployer); } I think the first example is more readable if there is no difference in performance.

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• Error: expected specifier-qualifier-list before 'QTVisualContextRef'

  - by Moonlight293

  Hi everyone, I am currently getting this error message in my header code, and I'm not sure as to why: "Error: expected specifier-qualifier-list before 'QTVisualContextRef'" #import <Cocoa/Cocoa.h> #import <QTKit/QTKit.h> #import <OpenGL/OpenGL.h> #import <QuartzCore/QuartzCore.h> #import <CoreVideo/CoreVideo.h> @interface MyRecorderController : NSObject { IBOutlet QTCaptureView *mCaptureView; IBOutlet NSPopUpButton *videoDevicePopUp; NSMutableDictionary *namesToDevicesDictionary; NSString *defaultDeviceMenuTitle; CVImageBufferRef mCurrentImageBuffer; QTCaptureDecompressedVideoOutput *mCaptureDecompressedVideoOutput; QTVisualContextRef qtVisualContext; // the context the movie is playing in // filters for CI rendering CIFilter *colorCorrectionFilter; // hue saturation brightness control through one CI filter CIFilter *effectFilter; // zoom blur filter CIFilter *compositeFilter; // composites the timecode over the video CIContext *ciContext; QTCaptureSession *mCaptureSession; QTCaptureMovieFileOutput *mCaptureMovieFileOutput; QTCaptureDeviceInput *mCaptureDeviceInput; } @end In the examples I have seen through other code (e.g. Cocoa Video Tutorial) I have not seen any difference in their code to mine. If anyone would be able to point out as to how this error could have occurred that would be great. Thanks heaps! :)

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• Problem when compressing SWF in Linux with java.util.zip

  - by CaioToOn

  Hi! I've created a servlet that changes the binaries of a SWF file and output it to the user. The SWF is compressed by ZLIB by default. Then I inflate, change the binaries, deflate and output the result. Everything was running right on a Windows Server 2008 (also in 2003). Currently, we need change the server to Linux, and then, this servlet is somehow outputing a corrupted SWF File... what could be the problem? What intrigues me more is that there is no difference between the Windows and Linux servlet versions. Is there any undocumented linux specific behaviour for the java.util.zip package? My Windows Server is (where the servlet is working): Windows Server 2008 (6.0 - x86) Apache 2.2.11 Tomcat 6.0.16.0 Java JDK 1.6.0_12-b04 My CentOS Server is (where te servlet doesn't work) CentOS 5.4 (2.6.18-164.15.1.el5 - i386) Apache 2.2.3 Tomcat 6.0.16.0 Java JDK 1.6.0_12-b04 Any lead would be appreciated! Cheers, CaioToOn!

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• How to find every possible combination of an arbitrary number of arrays in PHP

  - by Travis

  I have an arbitrary number of nested arrays in php. For example: Array ( [0] => Array ( [0] => 36 [0] => 2 [0] => 9 ) [1] => Array ( [0] => 95 [1] => 21 [2] => 102 [3] => 38 ) [2] => Array ( [0] => 3 [1] => 5 ) ) I want to find the most efficient way to combine all possible combinations of each of these nested arrays. I'd like to end up with something that looks like this... Array ( [0] => "36,95,3" [1] => "36,95,5" [2] => "36,21,3" [3] => "36,21,5" etc... ) The order the results are combined in is not important. That is to say, there is no difference between "3,95,36", "36,95,3", and "95,36,3". I would like to omit these redundant combinations. Any suggestions on how to go about this would be much appreciated. Thanks in advance,

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• Does Function pointer make the program slow?

  - by drigoSkalWalker

  Hi guys. I read about function pointers in C And everyone said that will make my program run slow. Is it true? I made a program to check it. And I got the same results on both cases. (mesure the time.) So, is it bad to use fuction pointer? Thanks in advance. To response for some guys. I said 'run slow' for the time that I have compared on a loop. like this. int end = 1000; int i = 0; while (i < end) { fp = func; fp (); } When you execute this, i got the same time if I execute this. while (i < end) { func (); } So I think that function pointer have no difference of time and it don't make a program run slow as many people said.

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• rbind.zoo doesn't seem create consistent zoo object

  - by a-or-b

  I want to rbind.zoo two zoo object together. When I was testing I came across the following issue(?)... Note: The below is an example, there is clearly no point to it apart from being illustrative. I have an zoo object, call it, 'X'. I want to break it into two parts and then rbind.zoo them together. When I compare it to the original object then all.equal gives differences. It appears that the '$class' attribute differs, but I can't see how or why. Is I make these xts objects then the all.equal works as expected. i.e. ..... X.date <- as.POSIXct(paste("2003-", rep(1:4, 4:1), "-", sample(1:28, 10, replace = TRUE), sep = "")) X <- zoo(matrix(rnorm(24), ncol = 2), X.date) a <- X[c(1:3), ] # first 3 elements b <- X[c(4:6), ] # second 3 elements c <- rbind.zoo(a, b) # rbind into an object of 6 elements d <- X[c(1:6), ] # all 6 elements all.equal(c, d) # are they equal? ~~~~ all.equal gives me the following difference: "Attributes: < Component 3: Attributes: < Length mismatch: comparison on first 1 components "

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• Audio Streaming Latency

  - by killianmcc

  I'm writing a UDP local area network video chat system and have got the video and audio streams working. However I'm experiencing a little latency (about half a second) in the audio and was wondering what codecs would provide the least latency. I'm using NAudio (http://naudio.codeplex.com/) which provides me access to the following codecs for streaming; Speex Narrow Band (VBR) Speex Wide Band (16kHz)(VBR) Speex Ultra Wide Band (32kHz)(VBR) DSP Group TrueSpeech (8.5kbps) GSM 6.10 (13kbps) Microsoft ADPCM (32.8kbps) G.711 a-law (64kbps) G.722 16kHz (64kbps) G.711 mu-law (64kbps) PCM 8kHz 16 bit uncompressed (128kbps) I've tried them out and I'm not noticing much difference. Is there any others that I should download and try to reduce latency? I'm only going to be sending voice over the connection but I'm not really worried about quality or background noises too much. UPDATE I'm sending the audio in blocks like so; waveIn = new WaveIn(); waveIn.BufferMilliseconds = 50; waveIn.DeviceNumber = inputDeviceNumber; waveIn.WaveFormat = codec.RecordFormat; waveIn.DataAvailable += waveIn_DataAvailable; void waveIn_DataAvailable(object sender, WaveInEventArgs e) { if (connected) { byte[] encoded = codec.Encode(e.Buffer, 0, e.BytesRecorded); udpSender.Send(encoded, encoded.Length); } }

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• Cost of logic in a query

  - by FrustratedWithFormsDesigner

  I have a query that looks something like this: select xmlelement("rootNode", (case when XH.ID is not null then xmlelement("xhID", XH.ID) else xmlelement("xhID", xmlattributes('true' AS "xsi:nil"), XH.ID) end), (case when XH.SER_NUM is not null then xmlelement("serialNumber", XH.SER_NUM) else xmlelement("serialNumber", xmlattributes('true' AS "xsi:nil"), XH.SER_NUM) end), /*repeat this pattern for many more columns from the same table...*/ FROM XH WHERE XH.ID = 'SOMETHINGOROTHER' It's ugly and I don't like it, and it is also the slowest executing query (there are others of similar form, but much smaller and they aren't causing any major problems - yet). Maintenance is relatively easy as this is mostly a generated query, but my concern now is for performance. I am wondering how much of an overhead there is for all of these case expressions. To see if there was any difference, I wrote another version of this query as: select xmlelement("rootNode", xmlforest(XH.ID, XH.SER_NUM,... (I know that this query does not produce exactly the same, thing, my plan was to move the logic to PL/SQL or XSL) I tried to get execution plans for both versions, but they are the same. I'm guessing that the logic does not get factored into the execution plan. My gut tells me the second version should execute faster, but I'd like some way to prove that (other than writing a PL/SQL test function with timing statements before and after the query and running that code over and over again to get a test sample). Is it possible to get a good idea of how much the case-when will cost? Also, I could write the case-when using the decode function instead. Would that perform better (than case-statements)?

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• How can I spot subtle Lisp syntax mistakes?

  - by Marius Andersen

  I'm a newbie playing around with Lisp (actually, Emacs Lisp). It's a lot of fun, except when I seem to run into the same syntax mistakes again and again. For instance, here's something I've encountered several times. I have some cond form, like (cond ((foo bar) (qux quux)) ((or corge (grault warg)) (fred) (t xyzzy))) and the default clause, which returns xyzzy, is never carried out, because it's actually nested inside the previous clause: (cond ((foo bar) (qux quux)) ((or corge (grault warg)) (fred)) (t xyzzy)) It's difficult for me to see such errors when the difference in indentation is only one space. Does this get easier with time? I also have problems when there's a large distance between the (mal-)indented line and the line it should be indented against. let forms with a lot of complex bindings, for example, or an unless form with a long conditional: (defun test () (unless (foo bar (qux quux) (or corge (grault warg) (fred)))) xyzzy) It turns out xyzzy was never inside the unless form at all: (defun test () (unless (foo bar (qux quux) (or corge (grault warg) (fred))) xyzzy)) I auto-indent habitually and use parenthesis highlighting to avoid counting parentheses. For the most part it works like a breeze, but occasionally, I discover my syntax mistakes only by debugging. What can I do?

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