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  • How can I integrate advanced computations into a database field?

    - by ciclistadan
    My biological research involves the measurement of a cellular structure as it changes length throughout the course of observation (capturing images every minute for several hours). As my data sets have become larger I am trying to store them in an Access database, from which I would like to perform various queries about their changes in size. I know that the SELECT statement can incorporate some mathematical permutations, but I have been unable to incorporate many of my necessary calculations (probably due to my lack of knowledge). For example, one calculation involves determining the rate of change during specifically defined periods of growth. This calculation is entirely dependent on the raw data saved in the table, therefore I didn't this it would be appropriate to just calculate it in excel prior to entry into the field. So my question is, what would be the most appropriate method of performing this calculation. Should I attempt to string together a huge SELECT calculation in my QUERY, or is there a way to use another language (I know perl?) which can be called to populate the new query field? I'm not looking for someone to write the code, just where is it appropriate to incorporate each step. Also, I am currently using Office Access but would be interested in any mySQL answers as I may be moving to this platform at a later date. Thanks all!

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  • Using Zend_Db and multiple tables

    - by Yacoby
    I have a normalized database that stores locations of files on the internet. A file may have multiple locations spread across different sites. I am storing the urls in two parts (Site.UrlStart, FileLocation.UrlEnd). The UrlEnd is the part unique to that file (for the site). Simplified Db structure: I am using Zend_Db as my ORM (If it is that), with classes for the tables inheriting from Zend_Db_Table_Abstract. The issue is that retrieving the location data (e.g. the url) requires the use of multiple tables and as far as I can make out and I would either have to use both table classes (thereby exposing my table structure) or scatter sql all over my application, neither of which sound appealing. The only solution I can see is to create a façade that acts like Zend_Db_Table_Abstract (Maybe inherits from it?) and hides the fact that the data is actually on two tables. My questions are as follows: Am I going in the right direction in creating a façade class (Are there other alternatives)? Should the facade class inherit from Zend_Db_Table_Abstract?

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  • Add a banner at the top on unknown HTML page on the fly; Send a note to network user

    - by Vi
    I want to be able to send messages to users of network that my computer routes to. Modifying requested pages, by adding messages like Warning: this access point is going down soon" or Network quota exhausted or You are overusing the network connection and may be banned or Security notice: this is unencrypted network, so everybody around can see this page too It seems the only good solution (as there is no general "Send notice to users of my access point" thing). All traffic is already routed through -j REDIRECT, socat and remote SOCSK5 server, so intercepting unencrypted content should be easy. How it's better to add a message? Just inserting <div style="color:white; background-color:red">Sorry, connect_me access point is going down soon...</div> as the first element of <body> breaks design of some pages (f.e. Wikipedia). Should I also add some "Cache-control" directive to prevent persisting such messages? /* smdclient messages are poor solution, as them are Windows-only and can disturb users not using the network */

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  • UPDATE Table SET Field

    - by davlyo
    This is my Very first Post! Bear with me. I have an Update Statement that I am trying to understand how SQL Server handles it. UPDATE a SET a.vField3 = b.vField3 FROM tableName a INNER JOIN tableName b ON a.vField1 = b.vField1 AND b.nField2 = a.nField2 – 1 This is my query in its simplest form. vField1 is a Varchar nField2 is an int (autonumber) vField3 is a Varchar I have left the WHERE clause out so understand there is logic that otherwise makes this a nessessity. Say vField1 is a Customer Number and that Customer has 3 records The value in nField2 is 1, 2, and 3 consecutively. vField3 is a Status When the Update comes to a.nField2 = 1 there is no a.nField2 -1 so it continues When the Update comes to a.nField2 = 2, b.nField2 = 1 When the Update comes to a.nField2 = 3, b.nField2 = 2 So when the Update is on a.nField2 = 2, alias b reflects what is on the line prior (b.nField2 = 1) And it SETs the Varchar Value of a.vField3 = b.vField3 When the Update is on a.nField2 = 3, alias b reflects what is on the line prior (b.nField2 = 2) And it (should) SET the Varchar Value of a.vField3 = b.vField3 When the process is complete –the Second of three records looks as expected –hence the value in vField3 of the second record reflects the value in vField3 from the First record However, vField3 of the Third record does not reflect the value in vField3 from the Second record. I think this demonstrates that SQL Server may be producing a transaction of some sort and then an update. Question: How can I get the DB to Update after each transaction so I can reference the values generated by each transaction?

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  • Determining difference in timestamps for two values in the same MySQL table

    - by JayRizzo03
    I am relatively new to programming in PHP, so I apologize if this is a rather simple question. I have a MySQL database table called MachineReports that contains the following values: ReportNum(primary key, auto increment), MachineID and Timestamp Here is some example data: |ReportNum | MachineID | Timestamp | |1 | AD3203 | 2012-11-18 06:32:28| |2 | AD3203 | 2012-11-19 04:00:15| |3 | BC4300 | 2012-11-19 04:00:15| What I am attempting to do is find the difference in timestamps in seconds for each machine ID by iterating over each row set. I am getting stuck on the best way to do this, however. Here is the code I've written so far: <?php include '../dbconnect/dbconnect.php'; $machineID=[]; //Get a list of all MachineIDs in the database foreach($dbh->query('SELECT DISTINCT(MachineID) FROM MachineReports') as $row) { array_push($machineID, $row[0]); } for($i=0;$i<count($machineID);$i++){ foreach($dbh->query("SELECT MachineID FROM MachineReports WHERE MachineID='$machineID[$i]' ORDER BY MachineID") as $row) { //code to associate each machineID with two time stamps goes here } } ? This code just lists out the contents of the table row by row. My ultimate goal is to find the difference in timestamps for a certain MachineID. One of the things I've considered is using a multidimensional array in php - using the $machineID as the key and then storing the timestamp inside the array the key points to. However, I'm uncertain how to do that since my query parses row by row. I have quite a few questions. 1) Is this the most efficient way to be doing this? I suspect my database table design may not be the best. 2)What would be the best way to determine the difference in timestamps for a certain machineID? Even just a pointer to a topic that would prompt me to think about this in a different way would be helpful - I'm not afraid to do research. Thanks!

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  • dotNet Templated, Repeating, Databound ServerControl: Counting the templates OnDataBind?

    - by Campbeln
    I have a server control that wraps an underlying class which manages a number of indexes to track where it is in a dataset (ie: RenderedRecordCount, ErroredRecordCount, NewRecordCount, etc.). I've got the server control rendering great, but OnDataBinding I'm having an issue as to seems to happen after CreateChildControls and before Render (both of which properly manage the iteration of the underlying indexes). While I'm somewhat familiar with the ASP.NET page lifecycle, this one seems to be beyond me at the moment. So... how do I hook into the iterative process OnDataBinding uses so I can manage the underlying indexes? Will I have to iterate over the ITemplates myself, managing the indexes as I go or is there an easier solution? Also... I implemented the iteration of the underlying indexes during CreateChildControls originally in the belief that was the proper place to hook in for events like OnDataBinding (thining it was done as the controls were being .Add'd). Now it seems that this may actually be unnecessary. So I guess the secondary question is: What happens during CreateChildControls? Are the unadulterated (read: with <%-tags in place) controls added to the .Controls collection without any other processing?

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  • Vector Usage in MPI(C++)

    - by lsk1985
    I am new to MPI programming,stiil learning , i was successful till creating the Derived data-types by defining the structures . Now i want to include Vector in my structure and want to send the data across the Process. for ex: struct Structure{ //Constructor Structure(): X(nodes),mass(nodes),ac(nodes) { //code to calculate the mass and accelerations } //Destructor Structure() {} //Variables double radius; double volume; vector<double> mass; vector<double> area; //and some other variables //Methods to calculate some physical properties Now using MPI i want to sent the data in the structure across the processes. Is it possible for me to create the MPI_type_struct vectors included and send the data? I tried reading through forums, but i am not able to get the clear picture from the responses given there. Hope i would be able to get a clear idea or approach to send the data PS: i can send the data individually , but its an overhead of sending the data using may MPI_Send/Recieve if we consider the domain very large(say 10000*10000)

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  • [^.] causing headache in RewriteRule

    - by Ollie2893
    I am struggling with a very basic regex problem in my .htaccess file that I hope someone may be able to shed some light on. The basic premise is that I would like to teach Apache to switch any .html extension into a .var extension. I had thought that the rule would be positively trivial: RewriteRule ^([^.]+)\.html$ $1.var But the [^.] part simply doesn't work. Bizarrely, it works like so RewriteRule ^([^A-Z]+)\.html$ $1.var I do not understand why this latter rule works. Assume I am looking for a file called "index.html" then $1 should match to "index." and the ".html" bit should actually fail to match. To widen the scope of the question slightly, I am actually racking my brain on how to implement a multi-lingual site. I don't like Apache's MultiView option because it forces upon me a flat directory structure with file extensions that aren't recognizable to many development tools. I could go the .var type-map route but am finding that the default config for Apache doesn't support this all that well either (hence my excursions into regex land). So while I am using mod_rewrite, I am thinking that I might go the whole hog: whenever a request for a name.html file is received and this file does not exist, check whether there exists a XX/name.html file instead, where "XX" is the language code according to the user's preferences. This would give me a neater directory structure, though it does perhaps not perform as well as the .var approach in a situation where the language preference of the user's browser is not supported in by my site (in which situation .var would substitute EN or similar). Any thoughts? Thanks.

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  • (Java) Is there a type of object that can handle anything from primitives to arrays?

    - by Michael
    I'm pretty new to Java, so I'm hoping one of you guys knows how to do this. I'm having the user specify both the type and value of arguments, in any XML-like way, to be passed to methods that are external to my application. Example: javac myAppsName externalJavaClass methodofExternalClass [parameters] Of course, to find the proper method, we have to have the proper parameter types as the method may be overloaded and that's the only way to tell the difference between the different versions. Parameters are currently formatted in this manner: (type)value(/type), e.g. (int)71(/int) (string)This is my string that I'm passing as a parameter!(/string) I parse them, getting the constructor for whatever type is indicated, then execute that constructor by running its method, newInstance(<String value>), loading the new instance into an Object. This works fine and dandy, but as we all know, some methods take arrays, or even multi-dimensional arrays. I could handle the argument formatting like so: (array)(array)(int)0(/int)(int)1(/int)(/array)(array)(int)2(/int)(int)3(/int)(/array)(/array)... or perhaps even better... {{(int)0(/int)(int)1(/int)}{(int)2(/int)(int)3(/int)}}. The question is, how can this be implemented? Do I have to start wrapping everything in an Object[] array so I can handle primitives, etc. as argObj[0], but load an array as I normally would? (Unfortunately, I would have to make it an Object[][] array if I wanted to support two-dimensional arrays. This implementation wouldn't be very pretty.)

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  • implementing user tracking (logging) in Rails 3

    - by seth.vargo
    Hi, I'm creating a Rails application in which logging individual user actions is vital. Every time a user clicks a url, I want to log the action along with all parameters. Here is my current implementation: class CreateActivityLogs < ActiveRecord::Migration create_table :activity_logs do |t| t.references :user t.string :ip_address t.string :referring_url t.string :current_url t.text :params t.text :action t.timestamps end end   class ActivityLog < ActiveRecord::Base belongs_to :user end In a controller, I'd like to be able to do something like the following: ... ActivityLog::log @user.id, params, 'did foo with bar' ... I'd like to have the ActivityLog::log method automatically get the IP address, referring url, and current url (I know how to do this already) and create a new record in the table. So, my questions are: How do I do this? How do I use ActivityLog without having to create an instance everytime I want to log? Is this the best way? Some people have argued for a flat-file log for this kind of logging - however, I want admins to be able to see a user's activity in the backend as well, so I thought a database solution may be better?

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  • Initializing an object to all zeroes

    - by dash-tom-bang
    Oftentimes data structures' valid initialization is to set all members to zero. Even when programming in C++, one may need to interface with an external API for which this is the case. Is there any practical difference between: some_struct s; memset(s, 0, sizeof(s)); and simply some_struct s = { 0 }; Do folks find themselves using both, with a method for choosing which is more appropriate for a given application? For myself, as mostly a C++ programmer who doesn't use memset much, I'm never certain of the function signature so I find the second example is just easier to use in addition to being less typing, more compact, and maybe even more obvious since it says "this object is initialized to zero" right in the declaration rather than waiting for the next line of code and seeing, "oh, this object is zero initialized." When creating classes and structs in C++ I tend to use initialization lists; I'm curious about folks thoughts on the two "C style" initializations above rather than a comparison against what is available in C++ since I suspect many of us interface with C libraries even if we code mostly in C++ ourselves.

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  • HTML5 Local Storage of audio element source - is it possible?

    - by andrewdotcom
    Hi stackoverflow experts I've been experimenting with the audio and local storage features of html5 of late and have run into something that has me stumped. I'd like to be able to cache or store the source of the audio element locally to enable speedier and offline playback. The problem is I can't see how this is possible with the current implementation. I have tried the following using webkit: Creating a manifest file to set up local caching but the audio file appears not to be a cacheable item maybe due to the way it is stream or something I have also attempted to use javascript to put an audio object into local storage but the size of the mp3 makes this impossible due to memory issues (i think). I have tried to use the data uri and base64 to use the html as a audio transport that can be cached but again the filesize makes this prohibitive. Also the audio element does not seem to like this in webkit (works fine in mozilla) I have tried several methods of putting the data into the local database store. Again suffering the same issues as the other cases. I'd love to hear any other ideas anyone may have as to how I could achieve my goal of offline playback using caching/local storage in webkit.

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  • Why do you program? Why do you do what you do? [closed]

    - by Pirate for Profit
    To me, writing a new program is like a puzzle. Before you write any code for a large system, you have to carefully craft each piece in your mind and imagine how all the pieces will fit together. If you don't, your solution may end up being undefined. What I mean is, I often don't know what I'm doing so I'll come to this site and beg for a code snippet, and then somehow try to hack it into my projects. I started writing GW-Basic when I was around 8 years old. Then it progressed from there, went to california university and did some Python and C++, but really didn't learn anything(college = highsk00l++). I've mostly been self-taught, took awhile to break bad habits and I'd say only in recent years would I consider myself understanding of design patterns and all that stuff (no but honestly procedural dudes, I would not want to design and maintain a large system procedurally, yous crazy). And despite my username, money has NOT been a big motivator. I've gone from job to job, I can usually get the work done perfect very quickly, any delays on my part are understandable (well about as understandable as it gets in the industry). But I ain't gonna work for peanuts because I got mouths to feed. Why do you program? Why do you do what you do?

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  • In C# should I reuse a function / property parameter to compute cleaner temporary value or create a

    - by Hamish Grubijan
    The example below may not be problematic as is, but it should be enough to illustrate a point. Imagine that there is a lot more work than trimming going on. public string Thingy { set { // I guess we can throw a null reference exception here on null. value = value.Trim(); // Well, imagine that there is so much processing to do this.thingy = value; // That this.thingy = value.Trim() would not fit on one line ... So, if the assignment has to take two lines, then I either have to abusereuse the parameter, or create a temporary variable. I am not a big fan of temporary variables. On the other hand, I am not a fan of convoluted code. I did not include an example where a function is involved, but I am sure you can imagine it. One concern I have is if a function accepted a string and the parameter was "abused", and then someone changed the signature to ref in both places - this ought to mess things up, but ... who would knowingly make such a change if it already worked without a ref? Seems like it is their responsibility in this case. If I mess with the value of value, am I doing something non-trivial under the hood? If you think that both approaches are acceptable, then which do you prefer and why? Thanks.

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  • Complicated API issue with calling assemblies dynamically?

    - by Stefanos Tses
    I have an interesting challenge that I'm wondering if anyone here can give me some direction. I'm writing a .Net windows forms application that runs on a network and uses an SQL Server to save and pull data. I want to offer a mini "plugin" API, where developers can build their own assemblies and implement a specific interface (IDataManipulate). These assemblies then can be used by my application to call the interface functions and do something. I can create assemblies using my API, copy the file to a folder in my local hard drive and configure my application to use Reflection to call a specific function from the implemented interface (IDataManipulate.Execute). The problem: Since the application will be installed in multiple workstations in the network, is impossible to copy the plugin dlls the users will create to each machine. Solutions I tried: Solution 1 Copy the API dll to a network share. Problem: Requires AllowPartiallyTrustedCallersAttribute, which requires .Net singing, which I can't force from my users. Solution 2 (preferred) Serialize the dll object, save it to the database, deserialize it and call IDataManipulate.Execute. Problem: After deserialization, I try cast it to a IDataManipulate object but returns an error looking for the actual dll file. Solution 3 Save the dll bytes as byte[] to the database and recreate the dll at the local PC every time the user starts my application. Problem: Dll may have dependencies, which I don't know if I can detect. Any suggestions will be greatly appreciated. Thanks

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  • Syncing objects between two devices with different system times

    - by Mike Weller
    Hi there. I'm syncing objects between two devices. Objects have a lastModified property. If both devices have modified an object, then during the next sync the version of the object with the most recent lastModified is chosen on both devices. So we don't do fine-grained merging, only 'most recent version' merging. The problem is this. When one device receives a list of changed objects it can't reliably compare the lastModified of received objects to its own because the system times on the two devices may be different. I considered having each device send its current date/time during the sync. Then each calculates the difference between the remote time and the local time to compare the dates properly. But if there is lag between sending a date and the remote device receiving it, this causes incorrect comparisons with objects that were modified at the same time (or very close together in time). i.e. both devices think the remote object is newer and they end up with different objects. I hope I have explained this clearly enough. There must be a common solution to this kind of problem but my brain isn't coming up with anything. Any suggestions? Thanks in advance...

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  • Modifying html of dom element that was created after page loaded

    - by Ben321
    I have two separate AJAX calls. One that gets a list of items from a txt file and creates an HTML table out of them and one that talks to a database to find how much each item costs and then lists this in the corresponding table cell for each item (I know this may sound like a strange approach, but it's a good option in our case...). The issue is that the price is not getting written to the table since the table is created (or to be precise, the rows of the table are created) after the page loads. I'm not sure how to fix this. $(document).ready(function() { makeItemTable(); listPrices(); ... }); function makeItemTable() { $.ajax({ url: 'products.php', type: 'GET' }) .done(function(response) { $('.price-table > tbody').html(response); }) } function listPrices() { .ajax({ url: 'prices.php', type: 'GET' }) .done(function(response) { priceData = $.parseJSON(response); $('.price-table tr').each(function() { var item = $(this).find('td:nth-child(1)').text(); if (priceData[item]) { var price = priceData[item]; $(this).find('td:nth-child(2)').text(price); } }) }

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  • C++ - Where to throw exception?

    - by HardCoder1986
    Hello! I have some kind of an ideological question, so: Suppose I have some templated function template <typename Stream> void Foo(Stream& stream, Object& object) { ... } which does something with this object and the stream (for example, serializes that object to the stream or something like that). Let's say I also add some plain wrappers like (and let's say the number of these wrappers equals 2 or 3): void FooToFile(const std::string& filename, Object& object) { std::ifstream stream(filename.c_str()); Foo(stream, object); } So, my question is: Where in this case (ideologically) should I throw the exception if my stream is bad? Should I do this in each wrapper or just move that check to my Foo, so that it's body would look like if (!foo.good()) throw (something); // Perform ordinary actions I understand that this may be not the most important part of coding and these solutions are actually equal, but I just wan't to know "the proper" way to implement this. Thank you.

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  • How to store and synchronize a big list of strings

    - by Joel
    I have a large database table in SQLExpress on Windows, with a particular field of interest 'code'. I have an Apache web server with MySQL on Linux. The web application on the Linux box needs access to the list of all codes. The only thing it will use the list for is checking for the existence of a given code. Having the Linux server call out to the Windows server is impractical as the Windows server is behind a NAT'ed office internet connection, and it may not always be accessible. I have set it so the Windows server will push the list of codes to the web server by means of a simple HTTP POST request. However, at this point I have not implemented the storage of the codes on the Linux box. Should I store them in a MySQL table with a single field 'code'? Then I get fast indexed lookups O(1), however I think synchronization will be an issue - given an updated list of codes, pushed from the Windows box, how would I optimally synchronize the list with the database? TRUNCATE, followed by INSERT? Should I instead store them in a flat file? Then I have O(n) look up time rather than O(1). Additionally an extra constant-time overhead too, as I will be processing the file in Ruby. However, synchronization is easy - simply replace the file.

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  • [RAILS] Why is ssl_requirement clearing the Flash? (Chrome Mac)

    - by aaronrussell
    I am using ssl_requirement and since setting it up, my application's Flash messages are disappearing. I've modified the plugin slightly as accounts can optionally have a domain mapped to their account. In that case the non-ssl areas of the site should use the mapped domain, whereas the ssl areas should use the subdomain: def ensure_proper_protocol return true if ssl_allowed? if ssl_required? && !request.ssl? redirect_to "https://#{@account.subdomain}." + APP_CONF[:domain] + request.request_uri flash.keep return false elsif request.ssl? && !ssl_required? redirect_to "http://#{@account.sub_or_mapped_domain}" + request.request_uri flash.keep return false end end The application is broadly split into a website (front end) and an admin (back end). ALL of the admin area uses SSL so in the AdminController I have overwritten ssl_required? with: protected def ssl_required? return false if RAILS_ENV == "test" || RAILS_ENV == "development" true end Interestingly, Flash messages work fine in the development environment, where I am bypassing requiring SSL, but in my production environment where SSL is required, all Flash are gone. Any ideas? EDIT I've done some further testing and can add that this problem is ONLY occurring in Chrome on the Mac. Other Mac browsers and Chrome on windows are displaying the Flash messages as expected. This may be a bug with Chrome on the Mac then...?

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  • Best way to implement some type of ITaggable interface

    - by Jack
    I've got a program I'm creating that reports on another certain programs backup xml files. I've gotten to the point where I need to implement some type of ITaggable interface - but am unsure how to go about it code wise. My idea is that each item (BackupClient, BackupVersion, and BackupFile) should implement an ITaggable interface for highlighting old, out of date, or non-existent files in their HTML or Excel report. The user will be able to specify tags in the settings. My question is this, how can a user dynamically specify a "tag" such as File Date 3 days old? - Background Color = Red. Actually I guess my question is more, how can I, the programmer, implement this dynamically? I was thinking Expression trees, but am unsure this is the way to go as I havn't studied them much. I know my ITaggable interface would have methods such as AddTag(T tag), RemoveTag(T tag), but what exactly specifies the criteria for the tag to be added? I realize this may be subjective, and can be marked as wiki if need be, but I truly am stuck. Any input would be greatly helpful!

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  • Setting the mysql root user password on mac

    - by madaura
    I just Install MySQL on Mac OS X. The next step was setting the root user password, do I did the next: 1-Launch the terminal app to access the unix command line. 2-Under the unix prompt I executed the next commands: madaura$ cd /usr/local/mysql/bin madaura$ ./mysqladmin -u root password 'password' But, when I execute the command madaura$ ./mysql -u root, this is the answer: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 224 Server version: 5.5.13 MySQL Community Server (GPL) Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> I can get in to the mysql command line without password! Any ideas? Thanks a lot!

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  • How can I use SCM on linked files in VS2008 projects?

    - by Tom Bushell
    Background: I'm using Visual-SVN V. 1.7.5 with VS2008. I'm fairly new to SVN. I have a Solution that uses source files that will be shared with other Solutions. I've put these files in a folder called "Shared", and added them to my Solution using "Add - Existing Item... - Add As Link" which works fine as far as VS2008 is concerned. But when I try to add the linked files to SVN using the "Add to Suversion" menu item on the file's context menu, I get a warning: "...not added to Subversion because it is out of working copy. Please setup working copy root using Visual SVN - Set Working Copy Root menu". I tried this, but this seems to change the root directory of the whole solution - not what I want to do. Googling and searching SO indicates that I may want to set up some SVN Externals. I tried to follow the examples, using the command line for the first time with Visual-SVN. But I just got a bunch of error messages I didn't understand. Questions: Are Externals the way to go here? If so, can someone provide some detailed, step-by-step help on how to do this with Visual-SVN?

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  • Need help managing MySql connections

    - by David Jenings
    I'm having trouble finding a clear explanation of connection pooling. I'm building an app using the .NET connector I downloaded from mysql.com. The app only needs one db connection but will be running simultaneously on about 6 machines on my network. Normally, I'd create the connection at startup and just leave it. But I'm seeing lots of posts from people who say that's bad practice. Also I'm concerned about timeouts. My app will run 24/7 and there may be extended periods without database activity. I'm leaning toward the following: using (MySqlConnection conn = new MySqlConnection(connStr)) { conn.Open(); // use connection } But I'm not sure I understand what's going on in the background. Is this actually closing the connection and allowing gc to kill the object, or is there a built in pooling behavior that preserves the object and redelivers it the next time I try to create one? I certainly don't want the app reauthenticating across the network every time I hit the database. Can anyone offer me some advise?

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  • Defining implicit and explicit casts for C# interfaces

    - by ehdv
    Is there a way to write interface-based code (i.e. using interfaces rather than classes as the types accepted and passed around) in C# without giving up the use of things like implicit casts? Here's some sample code - there's been a lot removed, but these are the relevant portions. public class Game { public class VariantInfo { public string Language { get; set; } public string Variant { get; set; } } } And in ScrDictionary.cs, we have... public class ScrDictionary: IScrDictionary { public string Language { get; set; } public string Variant { get; set; } public static implicit operator Game.VariantInfo(ScrDictionary s) { return new Game.VariantInfo{Language=sd.Language, Variant=sd.Variant}; } } And the interface... public interface IScrDictionary { string Language { get; set; } string Variant { get; set; } } I want to be able to use IScrDictionary instead of ScrDictionary, but still be able to implicitly convert a ScrDictionary to a Game.VariantInfo. Also, while there may be an easy way to make this work by giving IScrDictionary a property of type Game.VariantInfo my question is more generally: Is there a way to define casts or operator overloading on interfaces? (If not, what is the proper C# way to maintain this functionality without giving up interface-oriented design?)

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