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  • why can't I comment lines in visual mode

    - by Haiyuan Zhang
    I want to comment several lines in my .vimrc, the usual way I do it is :x,ys/^/"/ and x stands for the start line number and y stands for the line number of the last line. I read some post which said in visual mode this task can be done by the following step: 1 Select your lines with VISUAL BLOCK 2 press I to insert before all highlighted lines. 3 type your comment charact , in this case should be " 4 then ESC I fllowed the above steps and met met problems in step 2 . the thing is when I select the lines in Visual mode and press I , vim ( I use version7.2) go back to insert mode and the cursor back to the start of the first line. so if you continue to do the step 3 and step 4, you end up in just inserting " at the start the first line , far from what I want to achieve. so could you point out what's wrong with the recipe ? thanks in advance

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  • Microsoft Access and Java JDBC-ODBC Error

    - by user1638362
    Trying to insert some values in a Microsoft access database using java. I can an error however, java.sql.SQLException: [Microsoft][ODBC Driver Manager] The specified DSN contains an architecture mismatch between the Driver and Application Exception in thread "main" java.lang.NullPointerException To create the data source im using SysWoW64 odbcad32 and adding it the datasource to system DNS. I say this as i have seen else where there are problems which occur with 64bit systems. However it still doesn't work for me. Microsoft Office 32bit. import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.sql.Statement; public class RMIAuctionHouseJDBC { /** * @param args */ public static void main(String[] args) { String theItem = "Car"; String theClient="KHAN"; String theMessage="1001"; Connection conn =null; // Create connection object try{ Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); System.out.println("Driver Found"); } catch(Exception e) { System.out.println("Driver Not Found"); System.err.println(e); } // connecting to database try{ String database ="jdbc:odbc:Driver={Microsoft Access Driver (*.accdb)};DBQ=AuctionHouseDatabase.accdb;"; conn = DriverManager.getConnection(database,"",""); System.out.println("Conn Found"); } catch(SQLException se) { System.out.println("Conn Not Found"); System.err.println(se); } // Create select statement and execute it try{ /*String insertSQL = "INSERT INTO AuctionHouse VALUES ( " +"'" +theItem+"', " +"'" +theClient+"', " +"'" +theMessage+"')"; */ Statement stmt = conn.createStatement(); String insertSQL = "Insert into AuctionHouse VALUES ('Item','Name','Price')"; stmt.executeUpdate(insertSQL); // Retrieve the results conn.close(); } catch(SQLException se) { System.out.println("SqlStatment Not Found"); System.err.println(se); } } } java.sql.SQLException: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified at sun.jdbc.odbc.JdbcOdbc.createSQLException(Unknown Source) at sun.jdbc.odbc.JdbcOdbc.standardError(Unknown Source) at sun.jdbc.odbc.JdbcOdbc.SQLDriverConnect(Unknown Source) at sun.jdbc.odbc.JdbcOdbcConnection.initialize(Unknown Source)

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  • ZIP Numerous Blob Files

    - by Michael
    I have a database table that contains numerous PDF blob files. I am attempting to combine all of the files into a single ZIP file that I can download and then print. Please help! <?php include 'config.php'; include 'connect.php'; $session= $_GET[session]; $query = " SELECT $tbl_uploads.username, $tbl_uploads.description, $tbl_uploads.type, $tbl_uploads.size, $tbl_uploads.content, $tbl_members.session FROM $tbl_uploads LEFT JOIN $tbl_members ON $tbl_uploads.username = $tbl_members.username WHERE $tbl_members.session= '$session'"; $result = mysql_query($query) or die('Error, query failed'); while(list($username, $description, $type, $size, $content) = mysql_fetch_array($result)) { header("Content-length: $size"); header("Content-type: $type"); header("Content-Disposition: inline; filename=$username-$description.pdf"); echo $content; } $files = array('File 1 from database', 'File 2 from database'); $zip = new ZipArchive; $zip->open('file.zip', ZipArchive::CREATE); foreach ($files as $file) { $zip->addFile($file); } $zip->close(); header('Content-Type: application/zip'); header('Content-disposition: attachment; filename=filename.zip'); header('Content-Length: ' . filesize($zipfilename)); readfile($zipname); mysql_close($link); exit; ?>

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  • Creating an Excel file using .NET (C#) - Problems with columns headers!

    - by tsocks
    Hello, I want to create & fill a .xls file using ADO.NET or LINQ, but I do not want to have the columns names in the first row. I just want to insert rows starting in row no. 1. I know I have to insert colums first, but... is there a way to 'hide' those columns headers? The problem is that, in first row of my spreadsheet, I must have only two values (one in A1 and the other in B1), but in the remaining rows I'll be inserting more than just two values (maximum 15 columns). I'm open to suggestions/hacks/tricks even if that's not the best way of doing this. Thanks!

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  • stumped by WSGI module import errors

    - by rguha
    Hi, I'm writing a bare bones Python wsgi application and am getting stumped by module import errors. I have a .py file in the current directory which initially failed to import. By adding sys.path.insert(0, '/Users/guhar/Sites/acom') the import of the module worked. But I now try and import a module that I had installed via easy_install and it fails to import. I tried setting sys.path.insert(0, '/Library/Python/2.5/site-packages/') which contains the egg file, but to no avail. I would've thought that all packages under "/Library/Python/2.5/site-packages/" would be available to a WSGI application. Does anybody have any pointers?

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  • Linq-to-SQL: How to shape the data with group by?

    - by Cheeso
    I have an example database, it contains tables for Movies, People and Credits. The Movie table contains a Title and an Id. The People table contains a Name and an Id. The Credits table relates Movies to the People that worked on those Movies, in a particular role. The table looks like this: CREATE TABLE [dbo].[Credits] ( [Id] [int] IDENTITY (1, 1) NOT NULL PRIMARY KEY, [PersonId] [int] NOT NULL FOREIGN KEY REFERENCES People(Id), [MovieId] [int] NOT NULL FOREIGN KEY REFERENCES Movies(Id), [Role] [char] (1) NULL In this simple example, the [Role] column is a single character, by my convention either 'A' to indicate the person was an actor on that particular movie, or 'D' for director. I'd like to perform a query on a particular person that returns the person's name, plus a list of all the movies the person has worked on, and the roles in those movies. If I were to serialize it to json, it might look like this: { "name" : "Clint Eastwood", "movies" : [ { "title": "Unforgiven", "roles": ["actor", "director"] }, { "title": "Sands of Iwo Jima", "roles": ["director"] }, { "title": "Dirty Harry", "roles": ["actor"] }, ... ] } How can I write a LINQ-to-SQL query that shapes the output like that? I'm having trouble doing it efficiently. if I use this query: int personId = 10007; var persons = from p in db.People where p.Id == personId select new { name = p.Name, movies = (from m in db.Movies join c in db.Credits on m.Id equals c.MovieId where (c.PersonId == personId) select new { title = m.Title, role = (c.Role=="D"?"director":"actor") }) }; I get something like this: { "name" : "Clint Eastwood", "movies" : [ { "title": "Unforgiven", "role": "actor" }, { "title": "Unforgiven", "role": "director" }, { "title": "Sands of Iwo Jima", "role": "director" }, { "title": "Dirty Harry", "role": "actor" }, ... ] } ...but as you can see there's a duplicate of each movie for which Eastwood played multiple roles. How can I shape the output the way I want?

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  • Rails 3.1. Cocoon link_to_add_association example needed

    - by BazZy
    pls show any example of using Cocoon's 'link_to_add_association' with html_options. https://github.com/nathanvda/cocoon Documentation says: html_options: extra html-options (see link_to) There are two extra options that allow to conrol the placement of the new link-data: data-association-insertion-node : the jquery selector of the node data-association-insertion-position : insert the new data before or after the given node. But i can not understand what to do, if i want insert partial just before my "add element" link. Not just after parent's div begin. This not gonna work: <%= link_to_add_association "add element", f, :production_years, :position = "after_all" %

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  • FormView templates break when refactored to Master/Content

    - by ZaijiaN
    Let's say I have an abstract class IA, with subclasses A1, A2, A3. For each subclass, I had a page with a FormView to insert/edit/view, with code specific to that class. The templates for insert/edit/view are all very similar, so it was mostly cut & paste, and the compiler had no problem that there were controls with the same IDs in the different templates. Something like this: <asp:FormView> <InsertItemTemplate> <asp:Label id="Label1" /> </InsertItemTemplate> <EditItemTemplate> <asp:Label id="Label1" /> </EdittItemTemplate> </asp:FormView> Much of the code/markup ended up being redundant across the pages, so I refactored it to use a master/content format, with the master page having content placeholders for the insert/edit/view templates. Master page: <asp:FormView> <InsertItemTemplate> <asp:ContentPlaceHolder ID="InsertItemTemplate"></asp:ContentPlaceHolder> </InsertItemTemplate> <EditItemTemplate> <asp:ContentPlaceHolder ID="EditItemTemplate"></asp:ContentPlaceHolder> </EdittItemTemplate> </asp:FormView> And content page: <asp:Content ContentPlaceHolderID="InsertItemTemplate"> <asp:Label id="Label1" /> </asp:Content> <asp:Content ContentPlaceHolderID="EditItemTemplate"> <asp:Label id="Label1" /> </asp:Content> In the content page templates, I'm doing the exact same thing I was doing before I refactored, but now the compiler is blowing up with the error BC30260: 'Label1' is already declared as 'Protected WithEvents Label1 As System.Web.UI.WebControls.Label' in this class. For some reason, it's not separating the controls in the content blocks the same way it did when they were in the templates, even though the content placeholders are in the individual templates. Is there a way around this, other than to rename all my controls?

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  • Oracle - Getting Select Count(*) from ... as an output parameter in System.Data.OracleClient

    - by cbeuker
    Greetings all, I have a question. I am trying to build a parametrized query to get me the number of rows from a table in Oracle. Rather simple. However I am an Oracle newbie.. I know in SQL Server you can do something like: Select @outputVariable = count(*) from sometable where name = @SomeOtherVariable and then you can set up an Output parameter in the System.Data.SqlClient to get the @outputVariable. Thinking that one should be able to do this in Oracle as well, I have the following query Select count(*) into :theCount from sometable where name = :SomeValue I set up my oracle parameters (using System.Data.OracleClient - yes I know it will be deprecated in .Net 4 - but that's what I am working with for now) as follows IDbCommand command = new OracleCommand(); command.CommandText = "Select count(*) into :theCount from sometable where name = :SomeValue"); command.CommandType = CommandType.Text; OracleParameter parameterTheCount = new OracleParameter(":theCount ", OracleType.Number); parameterTheCount .Direction = ParameterDirection.Output; command.Parameters.Add(parameterTheCount ); OracleParameter parameterSomeValue = new OracleParameter(":SomeValue", OracleType.VarChar, 40); parameterSomeValue .Direction = ParameterDirection.Input; parameterSomeValue .Value = "TheValueToLookFor"; command.Parameters.Add(parameterSomeValue ); command.Connection = myconnectionObject; command.ExecuteNonQuery(); int theCount = (int)parameterTheCount.Value; At which point I was hoping the count would be in the parameter parameterTheCount that I could readily access. I keep getting the error ora-01036 which http://ora-01036.ora-code.com tells me to check my binding in the sql statement. Am I messing something up in the SQL statement? Am I missing something simple elsewhere? I could just use command.ExecuteScaler() as I am only getting one item, and am probably going to end up using that, but at this point, curiosity has got the better of me. What if I had two parameters I wanted back from my query (ie: select max(ColA), min(ColB) into :max, :min.....) Thanks..

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  • URL Navigation and SQL Insertion After RadioButtonList Selection

    - by SidC
    Good Morning, I have a radiobuttonlist in my ASP.NET webforms application that is used as a voting tool. The concept is as follows: Users will vote for the blurb in the contentplaceholder using the radiobuttonlist. My list item values are 1 through 3 and my list item text is something like low, medium and high. Questions: 1. I want to save and accumulate votes for a given blurb. The blurb ID is referenced in a meta tag on the content page. How do I reference the meta tag in my SQL insert statement? 2. When the radiobuttonlist is used, can it cause the next content page to be loaded after the SQL insert is done? That is, I don't necessarily want the user to make the radiobuttonlist selection, then have to click a separate button to cast vote and move to next page. I want all that done in the radiobuttonlist. Is this possible? Thanks, Sid

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  • Is there any way to limit the size of an STL Map?

    - by Nathan Fellman
    I want to implement some sort of lookup table in C++ that will act as a cache. It is meant to emulate a piece of hardware I'm simulating. The keys are non-integer, so I'm guessing a hash is in order. I have no intention of inventing the wheel so I intend to use stl::map for this (though suggestions for alternatives are welcome). The question is, is there any way to limit the size of the hash to emulate the fact that my hardware is of finite size? I'd expect the hash's insert method to return an error message or throw an exception if the limit is reached. If there is no such way, I'll simply check its size before trying to insert, but that seems like an inelegant way to do it.

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  • Data tweaking code runs fine when executed directly - but never stops when used in trigger

    - by MBaas
    I have written some code to ensure that items on an order are all numbered (the "position number" or "item number" has been introduced only recently and we did not want to go and change all related code - as it is "asthetics only" and has no functional impact.) So, the idea is to go and check for an records that jave an itemno of NULL or 0 - and then compute one and assign it. When executing this code in a query window, it works fine. When putting it into an AFTER INSERT-trigger, it loops forever. So what is wrong here? /****** Objekt: Trigger [SetzePosNr] Skriptdatum: 02/28/2010 20:06:29 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TRIGGER [SetzePosNr] ON [dbo].[bestellpos] AFTER INSERT AS BEGIN DECLARE @idb int DECLARE @idp int DECLARE @pnr int SELECT @idp=id,@idb=id_bestellungen FROM bestellpos WHERE posnr IS NULL OR posnr=0 WHILE @idp IS NOT NULL BEGIN SELECT @pnr = 1+max(posnr) FROM bestellpos WHERE id_bestellungen = @idb print( 'idp=' + str(@idp) + ', idb=' + str(@idb) + ', posnr=' + str(@pnr)) UPDATE bestellpos SET posnr=@pnr WHERE id=@idp SELECT @idp=id,@idb=id_bestellungen FROM bestellpos WHERE posnr IS NULL OR posnr=0 END END

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  • I find a problem with sending receiving parameter

    - by kawtousse
    how to get the xml translation to html dropdownlist with ajax. I send the parameter with GET method but the JSP FILE THAT GENERATES THE XML DONT RECEIVE IT. var url="responsexml.jsp"; url=url+"?projectCode="+prj.options[prj.selectedIndex].value; xmlhttp.onreadystatechange=stateChanged; xmlhttp.open("GET",url,true); xmlhttp.send(null); and then in responsexml.jsp I do like that: <% String projectcode= (String)request.getParameter("projectCode"); System.out.println("++++projectCode:=" +projectcode); Session s = null; Transaction tx; try { s = HibernateUtil.currentSession(); tx = s.beginTransaction(); Query query = s.createQuery("SELECT from Wa wa where wa.ProjectCode='"+projectcode+"'"); response.setContentType("text/xml"); PrintWriter output = response.getWriter(); output.write( "<?xml version=\"1.0\" encoding=\"utf-8\"?>"); //response.setHeader("Cache-Control", "no-cache"); //constriure le xml if(projectcode!=null) { for(Iterator it=query.iterate();it.hasNext();) { if(it.hasNext()) { Wa object=(Wa)it.next(); //out.print( "<item id=\"" +object.getIdWA() + "\" name=\"" + object.getWAName() + "\" />"); output.write("<wa>"); output.write( "<item id=\"" + object.getIdWA() + "\" name=\"" + object.getWAName() + "\" />"); output.write("</wa>"); } } } } catch (HibernateException e) { e.printStackTrace(); } %> </body> </html> With this code I dont have my xml file. I got this error: The server did not understand the request, or the request was invalid. Erreur de traitement de la ressource http://www.w3.o... PLEASE HELP.

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  • NHibernate stored procedure problem

    - by Calvin
    I'm having a hard time trying to get my stored procedure works with NHibernate. The data returned from the SP does not correspond to any database table. This is my mapping file: <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="DomainModel" namespace="DomainModel.Entities"> <sql-query name="DoSomething"> <return class="SomeClass"> <return-property name="ID" column="ID"/> </return> exec [dbo].[sp_doSomething] </sql-query> </hibernate-mapping> Here is my domain class: namespace DomainModel.Entities { public class SomeClass { public SomeClass() { } public virtual Guid ID { get; set; } } } When I run the code, it fails with Exception Details: NHibernate.HibernateException: Errors in named queries: {DoSomething} at line 80 Line 78: config.Configure(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "NHibernate.config")); Line 79: Line 80: g_sessionFactory = config.BuildSessionFactory(); When I debug into NHibernate code, it seems that SomeClass is not added to the persister dictionary because there isn't a class mapping (only sql-query) defined in hbm.xml. And later on in CheckNamedQueries function, it is not able to find the persistor for SomeClass. I've checked all the obvious things (e.g. make hbm as an embedded resource) and my code isn't too much different from other samples I found on the web, but somehow I just can't get it working. Any idea how I can resolve this issue?

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  • inserting std::strings in to a std::map

    - by PaulH
    I have a program that reads data from a file line-by-line. I would like to copy some substring of that line in to a map as below: std::map< DWORD, std::string > my_map; DWORD index; // populated with some data char buffer[ 1024 ]; // populated with some data char* element_begin; // points to some location in buffer char* element_end; // points to some location in buffer > element_begin my_map.insert( std::make_pair( index, std::string( element_begin, element_end ) ) ); This std::map<>::insert() operation takes a long time (It doubles the file parsing time). Is there a way to make this a less expensive operation? Thanks, PaulH

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  • Inserting non-pod struct into a GHashTable

    - by RikSaunderson
    Hi there, I'm trying to build a GHashTable of instances of a struct containing ints, a time_t and a few char*'s. My question is, how do you insert an instance of a struct into a GHashTable? there are plenty of examples of how to insert a string or an int (using g_str_hash and g_int_hash respectively), but I'm guessing thatI want to use the g_direct_hash, and I can't seem to find any examples of that. Ideally, my code would look like this: GHashtable table; table = g_hash_table_new(g_direct_hash, g_direct_equal); struct mystruct; mystruct.a = 1; mystruct.b = "hello"; mystruct.c = 5; mystruct.d = "test"; g_hash_table_insert(table,mystruct.a,mystruct); Clearly, this is incorrect as it does not compile. Can anyone provide an example that does do what I want? Thanks, Rik

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  • C++ boost.asio server and client connection undersanding

    - by Edgar Buchvalov
    i started learning boost.asio and i have some problems with undersanding tcp connections. There is example from official boost site: #include <ctime> #include <iostream> #include <string> #include <boost/asio.hpp> using boost::asio::ip::tcp; std::string make_daytime_string() { using namespace std; // For time_t, time and ctime; time_t now = time(0); return ctime(&now); } int main() { try { boost::asio::io_service io_service; tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), 13)); for (;;) { tcp::socket socket(io_service); acceptor.accept(socket); std::string message = make_daytime_string(); boost::system::error_code ignored_error; boost::asio::write(socket, boost::asio::buffer(message), boost::asio::transfer_all(), ignored_error); } } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } there is question, why if i want to connet to this server via client i have t write: boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query(host_ip, "daytime"); //why daytime? tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); tcp::resolver::iterator end; why daytime?, what it meant and where it is inicialized in server, or i just doesn't missed somefing? there is full client code : www.boost.org/doc/libs/1_39_0/doc/html/boost_asio/tutorial/tutdaytime1.html thanks for explanation in advance

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  • PHP Post Count in Forum

    - by Chris
    I'm currently desiging a forum application, I considered using a premade but decided against it as it's useful for me to learn some of the techniques. So I've written a fairly full featured forum... great. One of the problems I want to solve is to include user data for each post, at the minute the post table includes the poster ID (obviously) and I added the poster's username at a later date so I didn't have to query the User DB for X number of posts in a thread. However, it's become apparent I now want to do this, usernames don't need to update retrospectively, however avatars, sigs, and especially post counts need to update actively, so data in some form needs keeping up to date somewhere... What would be a good way of implementing this? I obviously don't want to include any more user data on the Posts DB table than necessary, but I'm struggling to find an easy way to do this short of querying the DB for each post in a thread, which is potentially going to create a lot of traffic. How have other people solved this, I've been examining the code on some other open source apps but I can't find what I'm looking for. Is it possible to select multiple records in one query? In which case I could build an array dynamically on each page request (eg 'SQL blah blah' then a for each loop to insert the ID's). Could I join the tables each time? Do I submit a query for each post? Hmm.

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  • Help Reading Binary Image Data from SQL Server into PHP

    - by Joe Majewski
    I cannot seem to figure out a way to read binary data from SQL server into PHP. I am working on a project where I need to be able to store the image directly in the SQL table, not on the file system. Currently, I have been using a query like this one: INSERT INTO myTable(Document) SELECT * FROM OPENROWSET(BULK N'C:\image.jpg', SINGLE_BLOB) as BLAH This works fine to actually insert the image into the table, but I haven't yet figured a way to retrieve it and get my image back. I am doing this with PHP, and ultimately will have to make a stored procedure out of it, but can anyone enlighten me on a way to get that binary data (varbinary(MAX)) and generate an image on the fly. I expected it to be simple to use a SELECT statement and add a content-type to the headers that indicated it was an image, but it's simply not working. Instead, the page will just display the name of the file, which I have encountered in the past and understand it to be an error with the image data.

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  • Checking inherited attributes in an 'ancestry' based SQL table

    - by Brendon Muir
    I'm using the ancestry gem to help organise my app's tree structure in the database. It basically writes a childs ancestor information to a special column called 'ancestry'. The ancestry column for a particular child might look like '1/34/87' where the parent of this child is 87, and then 87's parent is 34 and 34's is 1. It seems possible that we could select rows from this table each with a subquery that checks all the ancestors to see if a certain attribute it set. E.g. in my app you can hide an item and its children just by setting the parent element's visibility column to 0. I want to be able to find all the items where none of their ancestors are hidden. I tried converting the slashes to comma's with the REPLACE command but IN required a set of comma separated integers rather than one string with comma separated string numbers. It's funny, because I can do this query in two steps, e.g. retrieve the row, then take its ancestry column, split out the id's and make another query that checks that the id is IN that set of id's and that visibility isn't ever 0 and whala! But joining these into one query seems to be quite a task. Much searching has shown a few answers but none really do what I want. SELECT * FROM t1 WHERE id = 99; 99's ancestry column reads '1/34/87' SELECT * FROM t1 WHERE visibility = 0 AND id IN (1,34,87); kind of backwards, but if this returns no rows then the item is visible. Has anyone come across this before and come up with a solution. I don't really want to go the stored procedure route. It's for a rails app.

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  • Hibernate constraint ConstraintViolationException. Is there an easy way to ignore duplicate entries?

    - by vincent
    Basically I've got the below schema and I'm inserting records if they don't exists. However when it comes to inserting a duplicate it throws and error as I would expect. My question is whether there is an easy way to make Hibernate to just ignore inserts which would in effect insert duplicates? CREATE TABLE IF NOT EXISTS `method` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `name` varchar(10) DEFAULT NULL, PRIMARY KEY (`id`), UNIQUE KEY `name` (`name`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=2 ; SEVERE: Duplicate entry 'GET' for key 'name' Exception in thread "pool-11-thread-4" org.hibernate.exception.ConstraintViolationException: could not insert:

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  • Implementing Model-level caching

    - by Byron
    I was posting some comments in a related question about MVC caching and some questions about actual implementation came up. How does one implement a Model-level cache that works transparently without the developer needing to manually cache, yet still remains efficient? I would keep my caching responsibilities firmly within the model. It is none of the controller's or view's business where the model is getting data. All they care about is that when data is requested, data is provided - this is how the MVC paradigm is supposed to work. (Source: Post by Jarrod) The reason I am skeptical is because caching should usually not be done unless there is a real need, and shouldn't be done for things like search results. So somehow the Model itself has to know whether or not the SELECT statement being issued to it worthy of being cached. Wouldn't the Model have to be astronomically smart, and/or store statistics of what is being most often queried over a long period of time in order to accurately make a decision? And wouldn't the overhead of all this make the caching useless anyway? Also, how would you uniquely identify a query from another query (or more accurately, a resultset from another resultset)? What about if you're using prepared statements, with only the parameters changing according to user input? Another poster said this: I would suggest using the md5 hash of your query combined with a serialized version of your input arguments. This would require twice the number of serialization options. I was under the impression that serialization was quite expensive, and for large inputs this might be even worse than just re-querying. And is the minuscule chance of collision worth worrying about? Conceptually, caching in the Model seems like a good idea to me, but it seems in practicality the developer should have direct control over caching and write it into the controller. Thoughts/ideas? Edit: I'm using PHP and MySQL if that helps to narrow your focus.

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  • Porting join from Oracle to Postgres

    - by Grasper
    INSERT INTO MISSION_OBJECTIVE( MSN_INT_ID, MO_INT_ID, MO_MSN_CLASS_NM, MO_MSN_CLASS_CD, MO_MSN_TYPE, MO_PRIORITY, MO_COMMENT, MO_START_DT, MO_END_DT, ASP_AIRSPACE_NM, MO_OBJ_LOCATION, MO_ALO_LEG_ID, MO_ALO_ARRIVE_LOC) SELECT '1025', '1', 'AIRDROP', 'ADP', 'LAPES', NULL, COALESCE( NULL, ' '), TO_TIMESTAMP( '1002260900', 'YYMMDDHH24MI'), TO_TIMESTAMP( '1002260915', 'YYMMDDHH24MI'), 'TRANSIT ALPHA', 'TRANSIT ALPHA', '1', 'TRANSIT ALPHA' FROM AIRSPACE ASP, apsmain .MISSION_CLASS MC WHERE ASP.ASP_AIRSPACE_NM(+)= 'TRANSIT ALPHA' AND MC.MCS_MISSION_CLASS_NAME= 'AIRDROP' AND 'TRANSIT ALPHA' IS NOT NULL Is that exactly the same as: INSERT INTO MISSION_OBJECTIVE( MSN_INT_ID, MO_INT_ID, MO_MSN_CLASS_NM, MO_MSN_CLASS_CD, MO_MSN_TYPE, MO_PRIORITY, MO_COMMENT, MO_START_DT, MO_END_DT, ASP_AIRSPACE_NM, MO_OBJ_LOCATION, MO_ALO_LEG_ID, MO_ALO_ARRIVE_LOC) SELECT '1025', '1', 'AIRDROP', 'ADP', 'LAPES', NULL, COALESCE( NULL, ' '), TO_TIMESTAMP( '1002260900', 'YYMMDDHH24MI'), TO_TIMESTAMP( '1002260915', 'YYMMDDHH24MI'), 'TRANSIT ALPHA', 'TRANSIT ALPHA', '1', 'TRANSIT ALPHA' FROM AIRSPACE ASP, apsmain .MISSION_CLASS MC WHERE ASP.ASP_AIRSPACE_NM = 'TRANSIT ALPHA' AND MC.MCS_MISSION_CLASS_NAME= 'AIRDROP' AND 'TRANSIT ALPHA' IS NOT NULL I just deleted the (+). The part that is confusing me is that ASP.ASP_AIRSPACE_NM is being right joined to a constant.

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