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  • Single HTML Table from multiple MySQL tables

    - by David Chouinard
    Hi! I've been struggling for a while with this one; I'll try to explain it here as simply as possible. Consider this MySQL table: +----------+-----------+---------+--------+ |status_id |session_id |pilot_id |present | +----------+-----------+---------+--------+ |1 |61 |901 |1 | |2 |63 |901 |1 | |3 |62 |901 |0 | |4 |62 |902 |1 | |5 |63 |903 |1 | +----------+-----------+---------+--------+ Both session_id and pilot_id are foreign keys making reference to a primary key in another table. The same pilot_id can be associated with different session_id, but every pilot_id-session_id combination is unique. I need to make an HTML table (in PHP) that would display the data like this: +----------+---------+---------+---------+ | |61 |62 |63 | +----------+---------+---------+---------+ |901 |X | |X | |902 | |X | | |903 | | |X | +----------+---------+---------+---------+ Hence, rows are pilot_id and columns are session_id. When a pilot_id-session_id combination has a present value of 1, the corresponding cell should be checked. (ie. when the row-combination is zero or the combination does not exist in the MySQL table, nothing should appear in the HTML table) Phew. Any ideas? Thanks!

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  • ASP.NET 4.5 Bundling in Debug Mode - Stale Resources

    - by RPM1984
    Is there any way we can make the ASP.NET 4.5 Bundling functionality generate GUID's as part of the querystring when running in debug mode (e.g bundling turned OFF). The problem is when developing locally, the scripts/CSS files are generated like this: <script type="text/javascript" src="/Content/Scripts/myscript.js" /> So if i change that file, i need to do a hard-refresh (sometimes a few times) to get the file to be picked up by the browser - annoying. Is there any way we can make it render out like this: <script type="text/javascript" src="/Content/Scripts/myscript.js?v=x" /> Where x is a GUID (e.g always unique). Ideas? I'm on ASP.NET MVC 4.

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  • What's the coolest machine you've ever worked on?

    - by mxg
    What's the most exotic, coolest, unique, or interesting machine you've worked on? Most of us work on machines with x86 architectures using some Windows or Linux variant. I'm sure there are those of you out there who are working on or have worked on machines with experimental architecures, or operating systems. Maybe you worked on a machine that has some sigificance in the history of computing. I'd be interested to hear about it. I'm sure others reading SO will as well. EDIT: I appreciate all of you who took some time to talk about their experiences with interesting or unusual machines. I enjoyed reading your answers. Although it wasn't my intent to get nostalgic, I see that theme amongst the responses.

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  • Why isn't UTF-8 allowed as the "ANSI" code page?

    - by dan04
    The Windows _setmbcp function allows any valid code page... (except UTF-7 and UTF-8, which are not supported) OK, not supporting UTF-7 makes sense: Characters have non-unique representations and that introduces complexity and security risks. But why not UTF-8? As I understand it, the "ANSI" versions of the Windows API functions convert their arguments to UTF-16, call the equivalent "W" function, and convert any strings in the output to "ANSI". This is what I've been doing manually. So why can't Windows do it for me?

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  • Rails: Generated tokens missing occasionally

    - by Vincent Chan
    We generate an unique token for each user and store it on database. Everything is working fine in the local environment. However, after we upload the codes to the production server on Engine Yard, things become weird. We tried to register an account right after the deploy. It is working fine and we can see the token in the db. But after that, when we register new accounts, we cannot see any tokens. We only have NULL in the db. Not sure what caused this problem because we can't re-produce this in the local machine. Thanks for your help.

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  • mod,prime -> inverse possible

    - by Piet
    Hi all. I was wondering if one can do the following: We have: X is a product of N-primes, thus I assume unique. C is a constant. We can assure that C is a number that is part of the N-primes or not. Whichever will work best. Thus: X mod C = Z We have Z and C and we know that X was a product of N-primes, where N is restricted lets say first 100 primes. Is there anyway we can get back X?

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  • Complex Join - involving date ranges and sum...

    - by calumbrodie
    I have two tables that I need to join... I want to join table1 and table2 on 'id' - however in table two id is not unique. I only want one value returned for table two, and this value represents the sum of a column called 'total_sold' - within a specified date range (say one month).. SELECT ta.id, tb.total_sold as total_sold_this_week FROM table_a as ta LEFT JOIN table_b as tb ON ta.id=tb.id AND tb.date_sold BETWEEN ADDDATE(NOW(),INTERVAL -3 WEEK) AND NOW() this works but does not SUM the rows - only returning one row for each id... how do I get the sum from table b instead of only one row??? Please criticise if format of question could use more work - I can rewrite and provide sample data if required - this is a trivialised version of a much larger problem. -Thanks

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  • How to have a where clause on an insert or an update in Linq to Sql?

    - by Kelsey
    I am trying to convert the following stored proc to a LinqToSql call (this is a simplied version of the SQL): INSERT INTO [MyTable] ([Name], [Value]) SELECT @name, @value WHERE NOT EXISTS(SELECT [Value] FROM [MyTable] WHERE [Value] = @value) The DB does not have a constraint on the field that is getting checked for so in this specific case the check needs to be made manually. Also there are many items constantly being inserted as well so I need to make sure that when this specific insert happens there is no dupe of the value field. My first hunch is to do the following: using (TransactionScope scope = new TransactionScope()) { if (Context.MyTables.SingleOrDefault(t => t.Value == in.Value) != null) { MyLinqModels.MyTable t = new MyLinqModels.MyTable() { Name = in.Name, Value = in.Value }; // Do some stuff in the transaction scope.Complete(); } } This is the first time I have really run into this scenario so I want to make sure I am going about it the right way. Does this seem correct or can anyone suggest a better way of going about it without having two seperate calls? Edit: I am running into a similar issue with an update: UPDATE [AnotherTable] SET [Code] = @code WHERE [ID] = @id AND [Code] IS NULL How would I do the same check with Linqtosql? I assume I need to do a get and then set all the values and submit but what if someone updates [Code] to something other than null from the time I do the get to when the update executes? Same problem as the insert...

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  • Transactional isolation level needed for safely incrementing ids

    - by Knut Arne Vedaa
    I'm writing a small piece of software that is to insert records into a database used by a commercial application. The unique primary keys (ids) in the relevant table(s) are sequential, but does not seem to be set to "auto increment". Thus, I assume, I will have to find the largest id, increment it and use that value for the record I'm inserting. In pseudo-code for brevity: id = select max(id) from some_table id++ insert into some_table values(id, othervalues...) Now, if another thread started the same transaction before the first one finished its insert, you would get two identical ids and a failure when trying to insert the last one. You could check for that failure and retry, but a simpler solution might be setting an isolation level on the transaction. For this, would I need SERIALIZABLE or a lower level? Additionally, is this, generally, a sound way of solving the problem? Are the any other ways of doing it?

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  • Advice on e-commerce logging strategy

    - by yalestar
    I recently inherited an e-commerce app (Java/Struts) that I'm porting to Rails. The thing is, we frequently have to do forensics on orders by poring through the log files, and with the old app's logs (log4j wall of text) it's pretty hard to make sense of the individual orders when several people are placing orders simultaneously. So I'm soliciting advice on a good strategy for logging of these orders, like maybe logging each individual order to its own MongoDB collection based on unique cart ID? Or maybe group them by IP address? Something different entirely? Essentially, what is the best approach for logging of an online store so that it's easy to backtrace each user's interaction with the site?

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  • What algorithm can calculate the power set of a given set?

    - by ross
    I would like to efficiently generate a unique list of combinations of numbers based on a starting list of numbers. example start list = [1,2,3,4,5] but the algorithm should work for [1,2,3...n] result = [1],[2],[3],[4],[5] [1,2],[1,3],[1,4],[1,5] [1,2,3],[1,2,4],[1,2,5] [1,3,4],[1,3,5],[1,4,5] [2,3],[2,4],[2,5] [2,3,4],[2,3,5] [3,4],[3,5] [3,4,5] [4,5] Note. I don't want duplicate combinations, although I could live with them, eg in the above example I don't really need the combination [1,3,2] because it already present as [1,2,3]

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  • ASP.NET MVC pass information from controller to view WITHOUT ViewData, ViewModel, or Session

    - by josh
    I have a unique scenario where I want a base controller to grab some data and store it in a list. The list should be accessible from my views just as ViewData is. I will be using this list on every page and would like a cleaner solution than just shoving it in the ViewDataDictionary. After attempting to come up with a solution, I thought I would create a custom ViewPage with a property to hold my list. My custom ViewPage would inherit from System.Web.MVC.ViewPage. However, I do not know where MVC passes the viewdata from the controller off to the view. More importantly, how do I get it to pass my list down to the view? Thanks for the help.

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  • Finding the index of a queue that holds a member of a containing object for a given value

    - by Luke Mcneice
    I have a Queue that contains a collection of objects, one of these objects is a class called GlobalMarker that has a member called GlobalIndex. What I want to be able to do is find the index of the queue where the GlobalIndex contains a given value (this will always be unique). Simply using the Contains method shown below returns a bool. How can I obtain the queue index of this match? RealTimeBuffer .OfType<GlobalMarker>() .Select(o => o.GlobalIndex) .Contains(INT_VALUE);

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  • INSERT INTO ... SELECT FROM ... ON DUPLICATE KEY UPDATE

    - by dnagirl
    I'm doing an insert query where most of many columns would need to be updated to the new values if a unique key already existed. It goes something like this: INSERT INTO lee(exp_id, created_by, location, animal, starttime, endtime, entct, inact, inadur, inadist, smlct, smldur, smldist, larct, lardur, lardist, emptyct, emptydur) SELECT id, uid, t.location, t.animal, t.starttime, t.endtime, t.entct, t.inact, t.inadur, t.inadist, t.smlct, t.smldur, t.smldist, t.larct, t.lardur, t.lardist, t.emptyct, t.emptydur FROM tmp t WHERE uid=x ON DUPLICATE KEY UPDATE ...; //update all fields to values from SELECT, except for exp_id, created_by, location, animal, starttime, endtime I'm not sure what the syntax for the UPDATE clause should be. How do I refer to the current row from the SELECT clause?

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  • SQL multiple primary keys - localization

    - by Max Malmgren
    I am trying to implement some localization in my database. It looks something like this (prefixes only for clarification) tbl-Categories ID Language Name tbl-Articles ID CategoryID Now, in my tbl-Categories, I want to have primary keys spanning ID and language, so that every combination of ID and language is unique. In tbl-Articles I would like a foreign key to reference ID in categories, but not Language, since I do not want to bind an article to a certain language, only category. Of course, I cannot add a foreign key to part of the primary key. I also cannot have the primary key only on the ID of categories, since then there can only be one language. Having no primary keys disables foreign keys altogether, and that is also not a great solution. Do you have any ideas how I can solve this in an elegant fashion? Thanks.

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  • DataTable throwing exception on RejectChanges

    - by Vale
    I found this bug while working with a DataTable. I added a primary key column to a DataTable, than added one row to that table, removed that row, and added row with the same key to the table. This works. When I tried to call RejectChanges() on it, I got ConstraintException saying that value is already present. Here is the example: var dataTable = new DataTable(); var column = new DataColumn("ID", typeof(decimal)); dataTable.Columns.Add(column); dataTable.PrimaryKey = new [] {column }; decimal id = 1; var oldRow = dataTable.NewRow(); oldRow[column] = id; dataTable.Rows.Add(oldRow); dataTable.AcceptChanges(); oldRow.Delete(); var newRow = dataTable.NewRow(); newRow[column] = id; dataTable.Rows.Add(newRow); dataTable.RejectChanges(); // This is where it crashes I think since the row is deleted, exception should not be thrown (constraint is not violated because row is in deleted state). Is there something I can do about this? Any help is appreciated.

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  • How can I force a ListView with a custom panel to re-measure when the ListView width goes below the

    - by Scott Whitlock
    Sorry for the long winded question (I'm including background here). If you just want the question, go to the end. I have a ListView with a custom Panel implementation that I'm using to implement something similar to a WrapPanel, but not quite. I'm overriding the MeasureOverride and ArrangeOverride methods in the custom panel. If I do the naive implementation of a WrapPanel in the MeasureOverride method it doesn't work when the ListView is resized. Let's say the custom panel does a measure and the constraint is a width of 100 and let's say I have 3 items that are 40 wide each. The naive approach is to return a size of 80,80 but when I resize the window that the ListView is in, down to say 75, it just turns on the horizontal scrollbar and never calls measure or arrange again (it does keep measuring and arranging if the width is greater than 80). To get around this, I hard coded the measurement to only have a width of the widest item. Then in the arrange, it gives me more space than I asked for and I use as much horizontal space as I can before wrapping. If I resize the window smaller than the smallest item in the ListView, then it turns on the scrollbar, which is great. Unfortunately this is causing a big problem when I have one of these ListViews with a custom panel nested inside of another one. The outside one works ok, but I can't get the inside one to "take as much as it needs". It always sizes to the smallest item, and the only way around it is to set the MinWidth to be something greater than zero. Anyway, stepping back for a second, I think the real way to fix this is to go back to the Naive implementation of the WrapPanel but force it to re-measure when the ListView width goes below the Size I previously returned as a measurement. That should solve my problem with the nested one. So, that's my question: I have a ListView with a custom panel If I return a measurement width on the panel and the ListView is resized to less than that width, it stops calling MeasureOverride How can I get it to continue calling MeasureOverride?

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  • How to perform COUNT() or COUNT(*)

    - by ninumedia
    I have a list of tags in a database. Ex: villan hero spiderman superman superman I wanted to obtain a sorted list of the tag names in ascending order and the number of times the unique tag appeared in the database. I wrote this code: Ex: SELECT hashtag.tag_name, COUNT( * ) AS number FROM hashtag GROUP BY hashtag.tag_name ORDER BY hashtag.tag_name ASC This yields the correct result: hero - 1 spiderman - 1 superman - 2 villan - 1 How can I obtain the full COUNT of this entire list. The answer should be 4 in this case because there are naturally 4 rows. I can't seem to get a correct COUNT() without the statement failing. Thanks so much for the help! :)

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  • gethostbyname in C

    - by Matic
    I don't know how to write applications in C, but I need a tiny program that does: lh = gethostbyname("localhost"); output = lh->h_name; output variable is to be printed. The above code is used in PHP MongoDB database driver to get the hostname of the computer (hostname is part of an input to generate an unique ID). I'm skeptical that this will return the hostname, so I'd like some proof. Any code examples would be most helpful. Happy day, Matic

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  • Hibernate: deletes not cascading for self-referencing entities

    - by jwaddell
    I have the following (simplified) Hibernate entities: @Entity @Table(name = "package") public abstract class Package { protected Content content; @ManyToOne(cascade = {javax.persistence.CascadeType.ALL}) @JoinColumn(name = "content_id") @Fetch(value = FetchMode.JOIN) public Content getContent() { return content; } public void setContent(Content content) { this.content = content; } } @Entity @Table(name = "content") public class Content { private Set<Content> subContents = new HashSet<Content>(); @ManyToMany(fetch = FetchType.EAGER) @JoinTable(name = "subcontents", joinColumns = {@JoinColumn(name = "content_id")}, inverseJoinColumns = {@JoinColumn(name = "elt")}) @Cascade(value = {org.hibernate.annotations.CascadeType.DELETE, org.hibernate.annotations.CascadeType.REPLICATE}) @Fetch(value = FetchMode.SUBSELECT) public Set<Content> getSubContents() { return subContents; } public void setSubContents(Set<Content> subContents) { this.subContents = subContents; } } So a Package has a Content, and a Content is self-referencing in that it has many sub-Contents (which may contain sub-Contents of their own etc). The relationships are required to be ManyToOne (Package to Content) and ManyToMany (Content to sub-Contents) but for the case I am currently testing each sub-Content only relates to one Package or Content. The problem is that when I delete a Package and flush the session, I get a Hibernate error stating that I'm violating a foreign key constraint on table subcontents, with a particular content_id still referenced from table subcontents. I've tried specifically (recursively) deleting the Contents before deleting the Package but I get the same error. Is there a reason why this entity tree is not being deleted properly?

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  • Password reset by email without a database table

    - by jpatokal
    The normal flow for resetting a user's password by mail is this: Generate a random string and store it in a database table Email string to user User clicks on link containing string String is validated against database; if it matches, user's pw is reset However, maintaining a table and expiring old strings etc seems like a bit of an unnecessary hassle. Are there any obvious flaws in this alternative approach? Generate a MD5 hash of the user's existing password Email hash string to user User clicks on link containing string String is validated by hashing existing pw again; if it matches, user's pw is reset Note that the user's password is already stored in a hashed and salted form, and I'm just hashing it once more to get a unique but repeatable string. And yes, there is one obvious "flaw": the reset link thus generated will not expire until the user changes their password (clicks the link). I don't really see why this would be a problem though -- if the mailbox is compromised, the user is screwed anyway.

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  • Quickly retrieve the subset of properties used in a huge collection in C#

    - by ccornet
    I have a huge Collection (which I can cast as an enumerable using OfType<()) of objects. Each of these objects has a Category property, which is drawn from a list somewhere else in the application. This Collection can reach sizes of hundreds of items, but it is possible that only, say, 6/30 of the possible Categories are actually used. What is the fastest method to find these 6 Categories? The size of the huge Collection discourages me from just iterating across the entire thing and returning all unique values, so is there a faster method of accomplishing this? Ideally I'd collect the categories into a List.

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  • What is the best method to write user "log files" of an android application to a file in a remote server or a table in a remote database?

    - by Samitha Chathuranga
    I am creating a multi user android application and it is connected to a php web service in a remote server and to a remote database via that web service. I want to keep a track of all the important activities done by the users. For an example if a user logged in to the app and changed his profile details and then logged out, a brief description of what he has done should be recorded(with time) somewhere. So then the admin of the system can see what the users are doing. So I think it is better to use log cat files and then flush all those data to a unique file in the server or a table in the database, when the user logs out or exists from his account. If it is appropriate How to do it?

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  • Identifying CDs

    - by Chris
    I'd like to be able to determine what music album CD is in a CD drive. For example, if someone claims that the CD in their drive is Eminem - The Eminem Show, I would like to be able to verify that the CD is indeed The Eminem Show. Any ideas? I've applied for a Gracenote developer license, but they won't get back to me for five days. Also, how does this work? Is there some GUID or other unique identifier that music discs are encoded with? Lastly, might this be possible with data CDs, like, say, the Diablo II install Disc 1? If so, any directions you can point me in, for accomplishing this?

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  • adding DATE_SUB to query to return range of values in mysql

    - by ian
    Here is my original query: $query = mysql_query("SELECT s.*, UNIX_TIMESTAMP(`date`) AS `date`, f.userid as favoritehash FROM songs s LEFT JOIN favorites f ON f.favorite = s.id AND f.userid = '$userhash' ORDER BY s.date DESC"); This returns all the songs in my DB and then joins data from my favorites table so I can display wich items a return visitors has clicked as favorites or not. Visitors are recognized by a unique has storred in a cookie and in the favorites table. I need to alter this query so that I can get just the last months worth of songs. Below is my attempt at adding DATE_SUB to my query: $query = mysql_query("SELECT s.*, UNIX_TIMESTAMP(`date`) AS `date`, f.userid as favoritehash FROM songs s WHERE `date` >= DATE_SUB( NOW( ) , INTERVAL 1 MONTH ) LEFT JOIN favorites f ON f.favorite = s.id AND f.userid = '$userhash' ORDER BY s.date DESC"); Suggestions?

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