Search Results

Search found 10966 results on 439 pages for 'kevin db'.

Page 381/439 | < Previous Page | 377 378 379 380 381 382 383 384 385 386 387 388  | Next Page >

  • KD-Trees and missing values (vector comparison)

    - by labratmatt
    I have a system that stores vectors and allows a user to find the n most similar vectors to the user's query vector. That is, a user submits a vector (I call it a query vector) and my system spits out "here are the n most similar vectors." I generate the similar vectors using a KD-Tree and everything works well, but I want to do more. I want to present a list of the n most similar vectors even if the user doesn't submit a complete vector (a vector with missing values). That is, if a user submits a vector with three dimensions, I still want to find the n nearest vectors (stored vectors are of 11 dimensions) I have stored. I have a couple of obvious solutions, but I'm not sure either one seem very good: Create multiple KD-Trees each built using the most popular subset of dimensions a user will search for. That is, if a user submits a query vector of thee dimensions, x, y, z, I match that query to my already built KD-Tree which only contains vectors of three dimensions, x, y, z. Ignore KD-Trees when a user submits a query vector with missing values and compare the query vector to the vectors (stored in a table in a DB) one by one using something like a dot product. This has to be a common problem, any suggestions? Thanks for the help.

    Read the article

  • eclipse django using wrong settings.py in pythonpath

    - by user1290264
    I have pydev/django installed in eclipse, and it runs fine. However, after adding a second django project to eclipse and running the server ('http://127.0.0.1:8000') the pythonpath seems to be stuck on project2 even when I run project1. As a summary, I have two django projects: project1, project2. When I run the django server for project1 I get: Validating models... 0 errors found Django version 1.5, using settings 'project1.settings' Development server is running at 'http://127.0.0.1:8000/' Quit the server with CTRL-BREAK. The above seems to suggest that django is using the correct settings file; however, when I go to 'http://127.0.0.1:8000/' it displays the urls from project2. Also, if I go to 'http://127.0.0.1:8000/admin' the models are getting pulled from the sqlite.db file in project2 as well. I've even tried removing project2 from eclipse entirely and now at 'http://127.0.0.1:8000/admin' I get this error: Python Path: ['C:\Users\Brad\workspaces\In Progress\project2', 'C:\Users\Brad\workspaces\In Progress\project2', 'C:\Python27\DLLs', 'C:\Python27\lib', 'C:\Python27\lib\plat-win', 'C:\Python27\lib\lib-tk', 'C:\Python27', 'C:\Python27\lib\site-packages', 'C:\Windows\system32\python27.zip'] If I run the server on a different port with project1 the path seems to be fine: runserver 7000 --noreload Then 'http://127.0.0.1:7000/' uses project1's paths, but it doesn't seem like I should have to do this. Note: I have setup the run configurations as correctly as I know how. In the main tab, the project and main module both point to the correct project (project1), and the "PYTHONPATH that will be used in the run:" includes project1. Also, I have cleared my browser history, cookies, and everything that chrome would let me delete.

    Read the article

  • t-sql most efficient row to column? crosstab for xml path, pivot

    - by ajberry
    I am looking for the most performant way to turn rows into columns. I have a requirement to output the contents of the db (not actual schema below, but concept is similar) in both fixed width and delimited formats. The below FOR XML PATH query gives me the result I want, but when dealing with anything other than small amounts of data, can take awhile. select orderid ,REPLACE(( SELECT ' ' + CAST(ProductId as varchar) FROM _details d WHERE d.OrderId = o.OrderId ORDER BY d.OrderId,d.DetailId FOR XML PATH('') ),'&#x20;','') as Products from _orders o I've looked at pivot but most of the examples I have found are aggregating information. I just want to combine the child rows and tack them onto the parent. I should also point out I don't need to deal with the column names either since the output of the child rows will either be a fixed width string or a delimited string. For example, given the following tables: OrderId CustomerId ----------- ----------- 1 1 2 2 3 3 DetailId OrderId ProductId ----------- ----------- ----------- 1 1 100 2 1 158 3 1 234 4 2 125 5 3 101 6 3 105 7 3 212 8 3 250 for an order I need to output: orderid Products ----------- ----------------------- 1 100 158 234 2 125 3 101 105 212 250 or orderid Products ----------- ----------------------- 1 100|158|234 2 125 3 101|105|212|250 Thoughts or suggestions? I am using SQL Server 2k5. Example Setup: create table _orders ( OrderId int identity(1,1) primary key nonclustered ,CustomerId int ) create table _details ( DetailId int identity(1,1) primary key nonclustered ,OrderId int ,ProductId int ) insert into _orders (CustomerId) select 1 union select 2 union select 3 insert into _details (OrderId,ProductId) select 1,100 union select 1,158 union select 1,234 union select 2,125 union select 3,105 union select 3,101 union select 3,212 union select 3,250 using FOR XML PATH: select orderid ,REPLACE(( SELECT ' ' + CAST(ProductId as varchar) FROM _details d WHERE d.OrderId = o.OrderId ORDER BY d.OrderId,d.DetailId FOR XML PATH('') ),'&#x20;','') as Products from _orders o which outputs what I want, however is very slow for large amounts of data. One of the child tables is over 2 million rows, pushing the processing time out to ~ 4 hours. orderid Products ----------- ----------------------- 1 100 158 234 2 125 3 101 105 212 250

    Read the article

  • Maintaining a pool of DAO Class instances vs doing new operator

    - by Fazal
    we have been trying to benchmark our application performance in multiple way for sometime now. I always believed that object creation in java using Class.newInstance() was not slow (at least after 1.4 version of java). But we anyways did a test to use newInstance method vs mainitain an object pool of 1000 objects. We did about 200K iterations of loading data from DB using JDBC and populating these objects. I was amazed (even shocked) to see that newInstance code compared to object pool code was almost 10 times slower. These objects represent tables with about 50 fields and all string type. Can someone share there thoughts on this issue as now I am more confused if object pooling of atleast some DAO instances is a better option. The pool size as I see right now should be large enough to meet size of average requests. There is a flip side as my memory footprint will go up but I am beginning to wonder if this kind of idea makes sense atleast for some of the DAO entities representing tables of about 50 or more columns Please share your ideas and let me know if this has been tried by someone or am I missing some point here

    Read the article

  • C# reference collection for storing reference types

    - by ivo s
    I like to implement a collection (something like List<T>) which would hold all my objects that I have created in the entire life span of my application as if its an array of pointers in C++. The idea is that when my process starts I can use a central factory to create all objects and then periodically validate/invalidate their state. Basically I want to make sure that my process only deals with valid instances and I don't re-fetch information I already fetched from the database. So all my objects will basically be in one place - my collection. A cool thing I can do with this is avoid database calls to get data from the database if I already got it (even if I updated it after retrieval its still up-to-date if of course some other process didn't update it but that a different concern). I don't want to be calling new Customer("James Thomas"); again if I initted James Thomas already sometime in the past. Currently I will end up with multiple copies of the same object across the appdomain - some out of sync other in sync and even though I deal with this using timestamp field on the MSSQL server I'd like to keep only one copy per customer in my appdomain (if possible process would be better). I can't use regular collections like List or ArrayList for example because I cannot pass parameters by their real local reference to the their existing Add() methods where I'm creating them using ref so that's not to good I think. So how can this be implemented/can it be implemented at all ? A 'linked list' type of class with all methods working with ref & out params is what I'm thinking now but it may get ugly pretty quickly. Is there another way to implement such collection like RefList<T>.Add(ref T obj)? So bottom line is: I don't want re-create an object if I've already created it before during the entire application life unless I decide to re-create it explicitly (maybe its out-of-date or something so I have to fetch it again from the db). Is there alternatives maybe ?

    Read the article

  • dynamically created controls and responding to control events

    - by Dirk
    I'm working on an ASP.NET project in which the vast majority of the forms are generated dynamically at run time (form definitions are stored in a DB for customizability). Therefore, I have to dynamically create and add my controls to the Page every time OnLoad fires, regardless of IsPostBack. This has been working just fine and .NET takes care of managing ViewState for these controls. protected override void OnLoad(EventArgs e) { base.OnLoad(e); RenderDynamicControls() } private void RenderDynamicControls(){ //1. call service layer to retrieve form definition //2. create and add controls to page container } I have a new requirement in which if a user clicks on a given button (this button is created at design time) the page should be re-rendered in a slightly different way. So in addition to the code that executes in OnLoad (i.e. RenderDynamicControls()), I have this code: protected void MyButton_Click(object sender, EventArgs e) { RenderDynamicControlsALittleDifferently() } private void RenderDynamicControlsALittleDifferently() (){ //1. clear all controls from the page container added in RenderDynamicControls() //2. call service layer to retrieve form definition //3. create and add controls to page container } My question is, is this really the only way to accomplish what I'm after? It seems beyond hacky to effectively render the form twice simply to respond to a button click. I gather from my research that this is simply how the page-lifecycle works in ASP.NET: Namely, that OnLoad must fire on every Postback before child events are invoked. Still, it's worthwhile to check with the SO community before having to drink the kool-aid. On a related note, once I get this feature completed, I'm planning on throwing an UpdatePanel on the page to perform the page updates via Ajax. Any code/advice that make that transition easier would be much appreciated. Thanks

    Read the article

  • Auditing in Entity Framework.

    - by Gabriel Susai
    After going through Entity Framework I have a couple of questions on implementing auditing in Entity Framework. I want to store each column values that is created or updated to a different audit table. Rightnow I am calling SaveChanges(false) to save the records in the DB(still the changes in context is not reset). Then get the added | modified records and loop through the GetObjectStateEntries. But don't know how to get the values of the columns where their values are filled by stored proc. ie, createdate, modifieddate etc. Below is the sample code I am working on it. //Get the changed entires( ie, records) IEnumerable<ObjectStateEntry> changes = context.ObjectStateManager.GetObjectStateEntries(EntityState.Modified); //Iterate each ObjectStateEntry( for each record in the update/modified collection) foreach (ObjectStateEntry entry in changes) { //Iterate the columns in each record and get thier old and new value respectively foreach (var columnName in entry.GetModifiedProperties()) { string oldValue = entry.OriginalValues[columnName].ToString(); string newValue = entry.CurrentValues[columnName].ToString(); //Do Some Auditing by sending entityname, columnname, oldvalue, newvalue } } changes = context.ObjectStateManager.GetObjectStateEntries(EntityState.Added); foreach (ObjectStateEntry entry in changes) { if (entry.IsRelationship) continue; var columnNames = (from p in entry.EntitySet.ElementType.Members select p.Name).ToList(); foreach (var columnName in columnNames) { string newValue = entry.CurrentValues[columnName].ToString(); //Do Some Auditing by sending entityname, columnname, value } }

    Read the article

  • GET and XMLHttpRequest

    - by Neethusha
    i have an XMLHttpRequest.The request passes a parameter to my php server code in /var/www. But i cannot seem to be able to extract the parameter back at the server side. below i have pasted both the codes: javascript: function getUsers(u) { alert(u);//here u is 'http://start.ubuntu.com/9.10' xmlhttp=new XMLHttpRequest(); var url="http://localhost/servercode.php"+"?q="+u; xmlhttp.onreadystatechange= useHttpResponse; xmlhttp.open("GET",url,true); xmlhttp.send(null); } function useHttpResponse() { if (xmlhttp.readyState==4 ) { var response = eval('('+xmlhttp.responseText+')'); for(i=0;i<response.Users.length;i++) alert(response.Users[i].UserId); } } servercode.php: <?php $q=$_GET["q"]; //$q="http://start.ubuntu.com/9.10"; $con=mysql_connect("localhost","root","blaze"); if(!$con) {die('could not connect to database'.mysql.error()); } mysql_select_db("BLAZE",$con) or die("No such Db"); $result=mysql_query("SELECT * FROM USERURL WHERE URL='$q'"); if($result == null) echo 'nobody online'; else { header('Content-type: text/html'); echo "{\"Users\":["; while($row=mysql_fetch_array($result)) { echo '{"UserId":"'.$row[UsrID].'"},'; } echo "]}"; } mysql_close($con); ?> this is not giving the required result...although the commented statement , where the variable is assigned explicitly the value of the argument works...it alerts me the required output...but somehow the GET method's parameter is not reaching my php or thats how i think it is....pls help....

    Read the article

  • Translating Where() to sql

    - by MBoros
    Hi. I saw DamienG's article (http://damieng.com/blog/2009/06/24/client-side-properties-and-any-remote-linq-provider) in how to map client properties to sql. i ran throgh this article, and i saw great potential in it. Definitely mapping client properties to SQL is an awesome idea. But i wanted to use this for something a bit more complicated then just concatenating strings. Atm we are trying to introduce multilinguality to our Business objects, and i hoped we could leave all the existing linq2sql queries intact, and just change the code of the multilingual properties, so they would actually return the given property in the CurrentUICulture. The first idea was to change these fields to XMLs, and then try the Object.Property.Elements().Where(...), but it got stuck on the Elements(), as it couldnt translate it to sql. I read somewhere that XML fields are actually regarded as strings, and only on the app server they become XElements, so this way the filtering would be on the app server anyways, not the DB. Fair point, it wont work like this. Lets try something else... SO the second idea was to create a PolyGlots table (name taken from http://weblogic.sys-con.com/node/102698?page=0,1), a PolyGlotTranslations table and a Culture table, where the PolyGlots would be referenced from each internationalized property. This way i wanted to say for example: private static readonly CompiledExpression<Announcement, string> nameExpression = DefaultTranslationOf<Announcement> .Property(e => e.Name) .Is(e=> e.NamePolyGlot.PolyGlotTranslations .Where(t=> t.Culture.Code == Thread.CurrentThread.CurrentUICulture.Name) .Single().Value ); now unfortunately here i get an error that the Where() function cannot be translated to sql, what is a bit disappointing, as i was sure it will go through. I guess it is failing, cause the IEntitySet is basically an IEnumerable, not IQueryable, am i right? Is there another way to use the compiledExpressions class to achieve this goal? Any help appreciated.

    Read the article

  • Saving and retrieving image in SQL database from C# problem

    - by Mobin
    I used this code for inserting records in a person table in my DB System.IO.MemoryStream ms = new System.IO.MemoryStream(); Image img = Image_Box.Image; img.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); this.personTableAdapter1.Insert(NIC_Box.Text.Trim(), Application_Box.Text.Trim(), Name_Box.Text.Trim(), Father_Name_Box.Text.Trim(), DOB_TimePicker.Value.Date, Address_Box.Text.Trim(), City_Box.Text.Trim(), Country_Box.Text.Trim(), ms.GetBuffer()); but when i retrieve this with this code byte[] image = (byte[])Person_On_Application.Rows[0][8]; MemoryStream Stream = new MemoryStream(); Stream.Write(image, 0, image.Length); Bitmap Display_Picture = new Bitmap(Stream); Image_Box.Image = Display_Picture; it works perfectly fine but if i update this with my own generated Query like System.IO.MemoryStream ms = new System.IO.MemoryStream(); Image img = Image_Box.Image; img.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); Query = "UPDATE Person SET Person_Image ='"+ms.GetBuffer()+"' WHERE (Person_NIC = '"+NIC_Box.Text.Trim()+"')"; the next time i use the same code for retrieving the image and displaying it as used above . Program throws an exception

    Read the article

  • MYSQL not running on Ubuntu OS - Error 2002.

    - by mgj
    Hi, I am a novice to mysql DB. I am trying to run the MYSQL Server on Ubuntu 10.04. Through Synaptic Package Manager I am have installed the mysql version: mysql-client-5.1 I wonder that how was the database password set for the mysql-client software that I installed through the above way.It would be nice if you could enlighten me on this. When I tried running this database, I encountered the error given below: mohnish@mohnish-laptop:/var/lib$ mysql ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) mohnish@mohnish-laptop:/var/lib$ I referred to a similar question posted by another user. I didn't find a solution through the proposed answers. For instance when I tried the solutions posted for the similar question I got the following: mohnish@mohnish-laptop:/var/lib$ service start mysqld start: unrecognized service mohnish@mohnish-laptop:/var/lib$ ps -u mysql ERROR: User name does not exist. ********* simple selection ********* ********* selection by list ********* -A all processes -C by command name -N negate selection -G by real group ID (supports names) -a all w/ tty except session leaders -U by real user ID (supports names) -d all except session leaders -g by session OR by effective group name -e all processes -p by process ID T all processes on this terminal -s processes in the sessions given a all w/ tty, including other users -t by tty g OBSOLETE -- DO NOT USE -u by effective user ID (supports names) r only running processes U processes for specified users x processes w/o controlling ttys t by tty *********** output format ********** *********** long options *********** -o,o user-defined -f full --Group --User --pid --cols --ppid -j,j job control s signal --group --user --sid --rows --info -O,O preloaded -o v virtual memory --cumulative --format --deselect -l,l long u user-oriented --sort --tty --forest --version -F extra full X registers --heading --no-heading --context ********* misc options ********* -V,V show version L list format codes f ASCII art forest -m,m,-L,-T,H threads S children in sum -y change -l format -M,Z security data c true command name -c scheduling class -w,w wide output n numeric WCHAN,UID -H process hierarchy mohnish@mohnish-laptop:/var/lib$ which mysql /usr/bin/mysql mohnish@mohnish-laptop:/var/lib$ mysql ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) I even tried referring to http://forums.mysql.com/read.php?11,27769,84713#msg-84713 but couldn't find anything useful. Please let me know how I could tackle this error. Thank you very much..

    Read the article

  • C++ : Avoid lot of boolean variable for multiple verification conditions in trading app

    - by Naveen
    Hi i am a junior dev in trading app... we have a order refresh verification unit. It has to verify order confirmation from exchange. We send a bunch of different request in bulk ( NEW, MODIFY, CANCEL ) to exchange... Verification has to happen for max N times with each T intervals for all orders. if verification successful for all the order before N retry then fine.. otherwise we need to indicate as verification unsuccessfull. i hv done a basic coding done in very urgent like below for( N times ) { for_each ( sent_request_order ) // SENT { 1) get all the refreshed order from DB or shared mem i.e REFRESHED 2) find current sent order in REFRESHED if( not_found ) not refreshed from exchange, continue to next order if( found ) case NEW : //check for new status, mark verification done case MODIFY : //check for modified status.. //if not mark pending, go to next order, //revisit the same after T time case CANCEL : //check for cancelled status.. //if not mark pending, go to next order, //revisit the same after T time } if( all_verified ) exit from verification. wait ( T sec ) } order_verification_pending, order_verification_done, order_visited, order_not_visited, all_verified, all_not_verified ... lot of boolean flags used for indication.. is there any better approach for doing this.... splitting responsibilities across the classes......???? i know this is not a general question.... but still flags are making me tidious to handle...

    Read the article

  • Is this the right way to organize my database tables?

    - by Moss
    So I'm making a website that allows users to build contact lists. So their are users, the users have lists, and the lists have contacts. It seems to me that I need 3 tables for this but I just want to make sure. There would be a User table of course, and then a "List of Lists" table that has the username, and listname, as primary key along with whatever other info we want to attach to the lists as a whole. Finally, for lack of a better word, the List table which would again have the username/listname p.k., then the contact ID and notes and such that the user attaches to that contact on that specific list. I hope that is a clear explanation. For some reason I feel unsure about this arrangement. For one thing if the website becomes popular the List table could swell to billions of rows. And it also feels a little weird that everybody's list info is all jumbled up in the same table. I suppose I could create separate tables for each user and even for each list but that seems like a bad idea for other reasons. My db explanation assumes I can use foreign keys on my tables which at the moment isn't actually an option. If I can't get InnoDB tables enabled I will probably use ID's for the lists instead of depending on a compound key. Maybe I should do this anyway?

    Read the article

  • EF Forced Concurrency Checks

    - by Imran
    Hi, I have an issue with EF 4.0 that I hope someone can help with. I currently have an entity that I want to update in a last in wins fashion (i.e. ignore concurrency checks and just overwrite whats in the db with what is submitted). It seems Entity Framework not only includes the primary key of the entity in the where clause of the generated sql, but also any foreign key fields. This is annoying as it means that I don't get true last in wins semantics and need to know what value the fk field had before the update or I get a concurrency exception. I am aware that this can be short circuited by including a foreign key field as well as the navigation property on the entity. I would like to avoid this if possible as it's not a very clean solution. I was just wondering if there was any other way to override this behaviour? It seems like more of a bug than a feature. I have no problem with ef doing concurrency checks if I instruct it to do so but not being able to bypass concurrency completely is a bit of a hindrance as there are many valid scenarios where this is not needed

    Read the article

  • How to use SQLErrorCodeSQLExceptionTranslator and DAO class with @Repository in Spring?

    - by GuidoMB
    I'm using Spring 3.0.2 and I have a class called MovieDAO that uses JDBC to handle the db. I have set the @Repository annotations and I want to convert the SQLException to the Spring's DataAccessException I have the following example: @Repository public class JDBCCommentDAO implements CommentDAO { static JDBCCommentDAO instance; ConnectionManager connectionManager; private JDBCCommentDAO() { connectionManager = new ConnectionManager("org.postgresql.Driver", "postgres", "postgres"); } static public synchronized JDBCCommentDAO getInstance() { if (instance == null) instance = new JDBCCommentDAO(); return instance; } @Override public Collection<Comment> getComments(User user) throws DAOException { Collection<Comment> comments = new ArrayList<Comment>(); try { String query = "SELECT * FROM Comments WHERE Comments.userId = ?"; Connection conn = connectionManager.getConnection(); PreparedStatement stmt = conn.prepareStatement(query); stmt = conn.prepareStatement(query); stmt.setInt(1, user.getId()); ResultSet result = stmt.executeQuery(); while (result.next()) { Movie movie = JDBCMovieDAO.getInstance().getLightMovie(result.getInt("movie")); comments.add(new Comment(result.getString("text"), result.getInt("score"), user, result.getDate("date"), movie)); } connectionManager.closeConnection(conn); } catch (SQLException e) { e.printStackTrace(); //CONVERT TO DATAACCESSEXCEPTION } return comments; } } I Don't know how to get the Translator and I don't want to extends any Spring class, because that is why I'm using the @Repository annotation

    Read the article

  • SQL Server 2008 - Shrinking the Transaction Log - Any way to automate?

    - by Albert
    I went in and checked my Transaction log the other day and it was something crazy like 15GB. I ran the following code: USE mydb GO BACKUP LOG mydb WITH TRUNCATE_ONLY GO DBCC SHRINKFILE(mydb_log,8) GO Which worked fine, shrank it down to 8MB...but the DB in question is a Log Shipping Publisher, and the log is already back up to some 500MB and growing quick. Is there any way to automate this log shrinking, outside of creating a custom "Execute T-SQL Statement Task" Maintenance Plan Task, and hooking it on to my log backup task? If that's the best way then fine...but I was just thinking that SQL Server would have a better way of dealing with this. I thought it was supposed to shrink automatically whenever you took a log backup, but that's not happening (perhaps because of my log shipping, I don't know). Here's my current backup plan: Full backups every night Transaction log backups once a day, late morning (maybe hook the Log shrinking onto this...doesn't need to be shrank every day though) Or maybe I just run it once a week, after I run a full backup task? What do you all think?

    Read the article

  • security deleting a mysql row with jQuery $.post

    - by FFish
    I want to delete a row in my database and found an example on how to do this with jQuery's $.post() Now I am wondering about security though.. Can someone send a POST request to my delete-row.php script from another website? JS function deleterow(id) { // alert(typeof(id)); // number if (confirm('Are you sure want to delete?')) { $.post('delete-row.php', {album_id:+id, ajax:'true'}, function() { $("#row_"+id).fadeOut("slow"); }); } } PHP: delete-row.php <?php require_once("../db.php"); mysql_connect(DB_SERVER, DB_USER, DB_PASSWORD) or die("could not connect to database " . mysql_error()); mysql_select_db(DB_NAME) or die("could not select database " . mysql_error()); if (isset($_POST['album_id'])) { $query = "DELETE FROM albums WHERE album_id = " . $_POST['album_id']; $result = mysql_query($query); if (!$result) die('Invalid query: ' . mysql_error()); echo "album deleted!"; } ?>

    Read the article

  • How should I design my MYSQL table/s?

    - by yaya3
    I built a really basic php/mysql site for an architect that uses one 'projects' table. The website showcases various projects that he has worked on. Each project contained one piece of text and one series of images. Original projects table (create syntax): CREATE TABLE `projects` ( `project_id` int(11) NOT NULL auto_increment, `project_name` text, `project_text` text, `image_filenames` text, `image_folder` text, `project_pdf` text, PRIMARY KEY (`project_id`) ) ENGINE=MyISAM AUTO_INCREMENT=8 DEFAULT CHARSET=latin1; The client now requires the following, and I'm not sure how to handle the expansions in my DB. My suspicion is that I will need an additional table. Each project now have 'pages'. Pages either contain... One image One "piece" of text One image and one piece of text. Each page could use one of three layouts. As each project does not currently have more than 4 pieces of text (a very risky assumption) I have expanded the original table to accommodate everything. New projects table attempt (create syntax): CREATE TABLE `projects` ( `project_id` int(11) NOT NULL AUTO_INCREMENT, `project_name` text, `project_pdf` text, `project_image_folder` text, `project_img_filenames` text, `pages_with_text` text, `pages_without_img` text, `pages_layout_type` text, `pages_title` text, `page_text_a` text, `page_text_b` text, `page_text_c` text, `page_text_d` text, PRIMARY KEY (`project_id`) ) ENGINE=MyISAM AUTO_INCREMENT=8 DEFAULT CHARSET=latin1; In trying to learn more about MYSQL table structuring I have just read an intro to normalization and A Simple Guide to Five Normal Forms in Relational Database Theory. I'm going to keep reading! Thanks in advance

    Read the article

  • Beginner's guide for rails

    - by piemesons
    Hello friends i need a book/ tutorials for rails without using scoffold. All the books mentioned in the other questions are creating some depot application or etc using scaffold and then explaining things. I believe in the thing that creating big depot is worthless when you are not getting anything. All of my frnds are suggesting me to go for this pragmatic book. look i understand the book is good but i m not getting the proper things. I got the logic cause i m good in php doctrine. asp.net c c++ so i m getting the things but i m not feeling confident. I want to have a another book. Can anybody suggest me some other books. I m saying this cause it really feels good when u create a simple form and insert the values in db and u can retreive those values and MOST IMP you can explain the whole logic of the that small form application instaed of that colorfull Depot application in which things are done with scaffold and u r not getting the thing and u are confused abt the real picture.

    Read the article

  • How can I solve this NHibernate Querying in an n-tier architecture?

    - by Tyler Wright
    I've hit a wall with trying to decouple NHibernate from my services layer. My architecture looks like this: web - services - repositories - nhibernate - db I want to be able to spawn nhibernate queries from my services layer and possibly my web layer without those layers knowing what orm they are dealing with. Currently, I have a find method on all of my repositories that takes in IList<object[]> criteria. This allows me to pass in a list of criteria such as new object() {"Username", usernameVariable}; from anywhere in my architecture. NHibernate takes this in and creates a new Criteria object and adds in the passed in criteria. This works fine for basic searches from my service layer, but I would like to have the ability to pass in a query object that my repository translates into an NHibernate Criteria. Really, I would love to implement something like what is described in this question: Is there value in abstracting nhibernate criterion. I'm just not finding any good resources on how to implement something like this. Is the method described in that question a good approach? If so, could anyone provide some pointers on how to implement such a solution?

    Read the article

  • Updating a specific key/value inside of an array field with MongoDB

    - by Jesta
    As a preface, I've been working with MongoDB for about a week now, so this may turn out to be a pretty simple answer. I have data already stored in my collection, we will call this collection content, as it contains articles, news, etc. Each of these articles contains another array called author which has all of the author's information (Address, Phone, Title, etc). The Goal - I am trying to create a query that will update the author's address on every article that the specific author exists in, and only the specified author block (not others that exist within the array). Sort of a "Global Update" to a specific article that affects his/her information on every piece of content that exists. Here is an example of what the content with the author looks like. { "_id" : ObjectId("4c1a5a948ead0e4d09010000"), "authors" : [ { "user_id" : null, "slug" : "joe-somebody", "display_name" : "Joe Somebody", "display_title" : "Contributing Writer", "display_company_name" : null, "email" : null, "phone" : null, "fax" : null, "address" : null, "address2" : null, "city" : null, "state" : null, "zip" : null, "country" : null, "image" : null, "url" : null, "blurb" : null }, { "user_id" : null, "slug" : "jane-somebody", "display_name" : "Jane Somebody", "display_title" : "Editor", "display_company_name" : null, "email" : null, "phone" : null, "fax" : null, "address" : null, "address2" : null, "city" : null, "state" : null, "zip" : null, "country" : null, "image" : null, "url" : null, "blurb" : null }, ], "tags" : [ "tag1", "tag2", "tag3" ], "title" : "Title of the Article" } I can find every article that this author has created by running the following command: db.content.find({authors: {$elemMatch: {slug: 'joe-somebody'}}}); So theoretically I should be able to update the authors record for the slug joe-somebody but not jane-somebody (the 2nd author), I am just unsure exactly how you reach in and update every record for that author. I thought I was on the right track, and here's what I've tried. b.content.update( {authors: {$elemMatch: {slug: 'joe-somebody'} } }, {$set: {address: '1234 Avenue Rd.'} }, false, true ); I just believe there's something I am missing in the $set statement to specify the correct author and point inside of the correct array. Any ideas? **Update** I've also tried this now: b.content.update( {authors: {$elemMatch: {slug: 'joe-somebody'} } }, {$set: {'authors.$.address': '1234 Avenue Rd.'} }, false, true );

    Read the article

  • How to handle large dataset with JPA (or at least with Hibernate)?

    - by Roman
    I need to make my web-app work with really huge datasets. At the moment I get either OutOfMemoryException or output which is being generated 1-2 minutes. Let's put it simple and suppose that we have 2 tables in DB: Worker and WorkLog with about 1000 rows in the first one and 10 000 000 rows in the second one. Latter table has several fields including 'workerId' and 'hoursWorked' fields among others. What we need is: count total hours worked by each user; list of work periods for each user. The most straightforward approach (IMO) for each task in plain SQL is: 1) select Worker.name, sum(hoursWorked) from Worker, WorkLog where Worker.id = WorkLog.workerId group by Worker.name; //results of this query should be transformed to Multimap<Worker, Long> 2) select Worker.name, WorkLog.start, WorkLog.hoursWorked from Worker, WorkLog where Worker.id = WorkLog.workerId; //results of this query should be transformed to Multimap<Worker, Period> //if it was JDBC then it would be vitally //to set resultSet.setFetchSize (someSmallNumber), ~100 So, I have two questions: how to implement each of my approaches with JPA (or at least with Hibernate); how would you handle this problem (with JPA or Hibernate of course)?

    Read the article

  • Facebook App : Problem with storing user info

    - by Jack
    I want to store basic user info like name and proxied email into my MySQL database. Here's my code $user = $facebook->require_login($required_permissions = 'publish_stream','status_update','email'); $con = mysql_connect("xxxx","xxxxx","xxxxx"); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("xxx_userdb", $con); //Uptil Here it is working fine...No problem with db connection $fql_firstname = "select first_name from user where uid = '$user'"; $fql_lastname = "select last_name from user where uid = '$user'"; $fql_email = "select proxied_email from user where uid = '$user'"; $fql_fname_result = $facebook->api_client->fql_query($fql_firstname); $fql_lname_result = $facebook->api_client->fql_query($fql_lastname); $fql_email_result = $facebook->api_client->fql_query($fql_email); echo "<pre>FQL Result:" . print_r($fql_fname_result,true) . "</pre>"; echo "<pre>FQL Result:" . print_r($fql_lname_result,true) . "</pre>"; echo "<pre>FQL Result:" . print_r($fql_email_result,true) . "</pre>"; Here's the output I get FQL Result: FQL Result: FQL Result: What am I doing wrong?

    Read the article

  • Creating self-referential tables with polymorphism in SQLALchemy

    - by Jace
    I'm trying to create a db structure in which I have many types of content entities, of which one, a Comment, can be attached to any other. Consider the following: from datetime import datetime from sqlalchemy import create_engine from sqlalchemy import Column, ForeignKey from sqlalchemy import Unicode, Integer, DateTime from sqlalchemy.orm import relation, backref from sqlalchemy.ext.declarative import declarative_base Base = declarative_base() class Entity(Base): __tablename__ = 'entities' id = Column(Integer, primary_key=True) created_at = Column(DateTime, default=datetime.utcnow, nullable=False) edited_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False) type = Column(Unicode(20), nullable=False) __mapper_args__ = {'polymorphic_on': type} # <...insert some models based on Entity...> class Comment(Entity): __tablename__ = 'comments' __mapper_args__ = {'polymorphic_identity': u'comment'} id = Column(None, ForeignKey('entities.id'), primary_key=True) _idref = relation(Entity, foreign_keys=id, primaryjoin=id == Entity.id) attached_to_id = Column(Integer, ForeignKey('entities.id'), nullable=False) #attached_to = relation(Entity, remote_side=[Entity.id]) attached_to = relation(Entity, foreign_keys=attached_to_id, primaryjoin=attached_to_id == Entity.id, backref=backref('comments', cascade="all, delete-orphan")) text = Column(Unicode(255), nullable=False) engine = create_engine('sqlite://', echo=True) Base.metadata.bind = engine Base.metadata.create_all(engine) This seems about right, except SQLAlchemy doesn't like having two foreign keys pointing to the same parent. It says ArgumentError: Can't determine join between 'entities' and 'comments'; tables have more than one foreign key constraint relationship between them. Please specify the 'onclause' of this join explicitly. How do I specify onclause?

    Read the article

  • TransactionScope Prematurely Completed

    - by Chris
    I have a block of code that runs within a TransactionScope and within this block of code I make several calls to the DB. Selects, Updates, Creates, and Deletes, the whole gamut. When I execute my delete I execute it using an extension method of the SqlCommand that will automatically resubmit the query if it deadlocks as this query could potentially hit a deadlock. I believe the problem occurs when a deadlock is hit and the function tries to resubmit the query. This is the error I receive: The transaction associated with the current connection has completed but has not been disposed. The transaction must be disposed before the connection can be used to execute SQL statements. This is the simple code that executes the query (all of the code below executes within the using of the TransactionScope): using (sqlCommand.Connection = new SqlConnection(ConnectionStrings.App)) { sqlCommand.Connection.Open(); sqlCommand.ExecuteNonQueryWithDeadlockHandling(); } Here is the extension method that resubmits the deadlocked query: public static class SqlCommandExtender { private const int DEADLOCK_ERROR = 1205; private const int MAXIMUM_DEADLOCK_RETRIES = 5; private const int SLEEP_INCREMENT = 100; public static void ExecuteNonQueryWithDeadlockHandling(this SqlCommand sqlCommand) { int count = 0; SqlException deadlockException = null; do { if (count > 0) Thread.Sleep(count * SLEEP_INCREMENT); deadlockException = ExecuteNonQuery(sqlCommand); count++; } while (deadlockException != null && count < MAXIMUM_DEADLOCK_RETRIES); if (deadlockException != null) throw deadlockException; } private static SqlException ExecuteNonQuery(SqlCommand sqlCommand) { try { sqlCommand.ExecuteNonQuery(); } catch (SqlException exception) { if (exception.Number == DEADLOCK_ERROR) return exception; throw; } return null; } } The error occurs on the line that executes the nonquery: sqlCommand.ExecuteNonQuery();

    Read the article

< Previous Page | 377 378 379 380 381 382 383 384 385 386 387 388  | Next Page >