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  • Counting characters in an Access database column using SQL

    - by jzr
    I have the following table col1 col2 col3 col4 ==== ==== ==== ===== 1233 4566 ABCD CDEF 1233 4566 ACD1 CDEF 1233 4566 D1AF CDEF I need to count the characters in col3, so from the data in the previous table it would be: char count ==== ===== A 3 B 1 C 2 D 3 F 1 1 2 Is this possible to achieve by using SQL only? At the moment I am thinking of passing a parameter in to SQL query and count the characters one by one and then sum, however I did not start the VBA part yet, and frankly wouldn't want to do that. This is my query at the moment: PARAMETERS X Long; SELECT First(Mid(TABLE.col3,X,1)) AS [col3 Field], Count(Mid(TABLE.col3,X,1)) AS Dcount FROM TEST GROUP BY Mid(TABLE.col3,X,1) HAVING (((Count(Mid([TABLE].[col3],[X],1)))>=1)); Ideas and help are much appreciated, as I don't usually work with Access and SQL.

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  • Database connection via Hibernate in servlets

    - by blackliteon
    What is the best place in servlet for Hibernate code that returns HibernateSessionFactory ? I saw many examples: ones put db connection in service methods. Others - use smth like HibernateUtil (Singleton) that returns HibernateSessionFactory. I don't know is it safe to use HibernateUtil in multithreaded Servlets ?

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  • php syntax confusion accessing database result

    - by Babak
    I am trying to do the following: <?php foreach($sqlResult as $row): ?> <tr> <?php foreach($formdata['columns'] as $column): ?> <td><?php echo $row->$column['name']; ?></td> <?php endforeach; ?> </tr> <?php endforeach; ?> This does not work. $row is returned by my mysql query, it has the following : row-id, row-author, row-name and these work as they echo fine. $columns is the following array: 'columns' => array ( 1 => array ( 'name' => 'id' ), 2 => array ( 'name' => 'author' ), 3 => array ( 'name' => 'date' ), 4 => array ( 'name' => 'title' ) it also works fine as $column['name'] echoes id, author, date, title my question is how would it be possible for me to access the $row-method (is it a method?) by passing it a name from the array??

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  • How to optimize an database suggestion engine

    - by Dimitar Vouldjeff
    Hi, I`m making an online engine for item-to-item recommending movies. I have made some researches and I think that the best way to implement that is using pearson correlation and make a table with item1, item2 and correlation fields, but the problem is that after each rate of item I have to regenerate the correlation for in the worst case N records (where N is the number of items). Another think that I read is the following article, but I haven`t thought a way to implement it. So what is your suggestion to optimize this process? Or any other suggestions? Thanks.

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  • Saving multiple items per single database cell...

    - by eugeneK
    Hi, i have a countries list. Each user can check multiple countries. Once saved, this "user country list" will be used to get whether other users fit into countries certain user chose. Question is what would be the most efficient approach to this problem... I have one, one to save user selection as delimited list like Canada,USA,France ... in single varchar(max) field but problem with it would be that once user from Germany enters page i perform this check on. To search for Germany i would be needed to get all items and un-delimit each field to check against value or to use sql 'like' which again is pretty damn slow.. If you have better solution or some tips i would be glad to hear. Just to make sure, many users will have their own selections of countries from which and only they want to have users to land on their page. While millions of users will reach those pages. So the faster approach will be the better. technology, MSSQL and ASP.NET thanks

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  • Working with Database using LINQ to XML

    - by M.H
    Hi,I am Working on a project (C#) in the university and they said that we can't use a DBMS like SQL Server so we decide to use Linq and XML...we learned some basics in Linq to Xml But really we don't know how we can create tables and fields and work with them in Xml.any suggestions ?

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  • Check if Database raises a particular exception

    - by mcabral
    using Nhibernate; I'm trying to insert several values a on table which has an unique index on some columns. I'd like to know if a particular insert raises an exception for having violated the unique constraint. So, which particular exception type should i catch? I only want to catch this particular one and let all others go up. Thanks a lot!

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  • Java DAO caching

    - by santiagobasulto
    I'm developing a medium Java app, and i'm facing a small problem due to my lack of experience. I've a custom DAO, which gets "Article" objects from the Database. I've the Article class, and the DAO has a method called getArticle(int id), this method returns an Article. The Article has a Category object, and I'm using lazy loading. So, when I request for an article's category (Article a = new Article(); a.getCategory();) the Article class gets the Category from the DAO and then returns it. I'm now thinking to cache it, so when I request multiple times to an article's category, the database is only queried one time. My question is: where should I put that cache? I can put it on the Article class (in the DTO), or I can put it on the DAO class. What do you say?

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  • Java Archtecture Decision !!

    - by santiagobasulto
    Hi everybody! I'm developing a medium Java app, and i'm facing a small problem due to my lack of expirience. I've a custom DAO, which gets "Article" objects from the DataBase. I've the Article class, and the DAO has a method called getArticle(int id), this method returns an Article. The Article has a Category object, and i'm using lazy loading. So, when i request for an Article Category (Article a = new Article(); a.getCategory();) the Article class gets the Category from the DAO and then returns it. I'm now thinking to cache it, so when i request multiple times to an Article's category, the database is only queried one time. My question is: where should i put that cache? I can put it on the Article class (in the DTO), or i can put it on the DAO class. What do you say? Thanks!

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  • Position of object in database

    - by fl00r
    Hi! I have got model Team and I've got (i.e.) team = Team.first :offset => 20. Now I need to get number of position of my team in db table. I can do it in ruby: Team.all.index team #=> 20 But I am sure that I can write it on SQL and it will be less expensive for me with big tables.

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  • Performance of Multiple Joins

    - by geeko
    Greetings Overflowers, I need to query against objects with many/complex spacial conditions. In relational databases that is translated to many joins (possibly 10+). I'm new to this business and wondering whether to go with MS SQL Server 2008 R2 or Oracle 11g or document-based solutions such as RavenDB or simply go with some spacial database (GIS)... Any thoughts ? Regards UPDATE: Thank you all for your answers. Would anybody opt for document/spatial databases ? My database would consist of tens of millions to few billion records. Mostly read-only. Almost no updates unless in case of mistakes in input. Overnight inserts and not that frequent. The join tables are predicted beforehand but the number of self joins (tables joining themselves multiple times) is not. Small pages of results from such queries are going to be viewed on an highly interactive website so response time is critical. Any predictions on how this can perform on MS SQL Server 2008 R2 or Oracle 11g ? I'm also concerned about boosting performance by adding more servers, which one scales better ? How about PostgresQL ?

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  • Can't insert a record in a oracle database using C#

    - by Gya
    try { int val4 = Convert.ToInt32(tbGrupa.Text); string MyConString = "Data Source=**;User ID=******;Password=*****"; OracleConnection conexiune = new OracleConnection(MyConString); OracleCommand comanda = new OracleCommand(); comanda.Connection = conexiune; conexiune.Open(); comanda.Transaction = conexiune.BeginTransaction(); int id_stud = Convert.ToInt16(tbCodStud.Text); string nume = tbNume.Text; string prenume = tbPrenume.Text; string initiala_tatalui = tbInitiala.Text; string email = tbEmail.Text; string facultate = tbFac.Text; int grupa = Convert.ToInt16(tbGrupa.Text); string serie = tbSeria.Text; string forma_de_inv = tbFormaInvatamant.Text; DateTime data_acceptare_coordonare = dateTimePicker1.Value; DateTime data_sustinere_licenta = dateTimePicker2.Value; string sustinere = tbSustinereLicenta.Text; string parola_acces = tbParola.Text; try { comanda.Parameters.AddWithValue("id_stud", id_stud); comanda.Parameters.AddWithValue("nume", nume); comanda.Parameters.AddWithValue("prenume", prenume); comanda.Parameters.AddWithValue("initiala_tatalui", initiala_tatalui); comanda.Parameters.AddWithValue("facultate", facultate); comanda.Parameters.AddWithValue("email", email); comanda.Parameters.AddWithValue("seria", serie); comanda.Parameters.AddWithValue("grupa", grupa); comanda.Parameters.AddWithValue("forma_de_inv", forma_de_inv); comanda.Parameters.AddWithValue("data_acceptare_coordonare", data_acceptare_coordonare); comanda.Parameters.AddWithValue("data_sustinere_licenta", data_sustinere_licenta); comanda.Parameters.AddWithValue("sustinere_licenta", sustinere); comanda.Parameters.AddWithValue("parola_acces", parola_acces); comanda.Transaction.Commit(); MessageBox.Show("Studentul " + tbNume.Text + " " + tbPrenume.Text + " a fost adaugat în baza de date!"); } catch (Exception er) { comanda.Transaction.Rollback(); MessageBox.Show("ER1.1:" + er.Message); MessageBox.Show("ER1.2:" + er.StackTrace); } finally { conexiune.Close(); } } catch (Exception ex) { MessageBox.Show("ER2.1:"+ex.Message); MessageBox.Show("ER2.2:"+ex.StackTrace); }

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  • Rails database relationships

    - by Danny McClelland
    Hi Everyone, I have three models that I want to interact with each other. Kase, Person and and Company. I have (I think) setup the relationships correctly: class Kase < ActiveRecord::Base #HAS ONE COMPANY has_one :company #HAS MANY PERSONS has_many :persons class Person < ActiveRecord::Base belongs_to :company class Company < ActiveRecord::Base has_many :persons def to_s; companyname; end I have put the select field on the create new Kase view, and the create new Person view as follows: <li>Company<span><%= f.select :company_id, Company.all %> </span></li> All of the above successfully shows a drop down menu dynamically populated with the company names within Companies. What I am trying to do is display the contact of the Company record within the kase and person show.html.erb. For example, If I have a company called "Acme, Inc." and create a new Kase called "Random Case" and choose within the create new case page "Acme, Inc." from the companies drop down menu. I would then want to display "Acme, Inc" along with "Acme, Inc. Mobile" etc. on the "Random Case" show.html.erb. I hope this makes sense to somebody! Thanks, Danny

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  • Best way to create a SPARQL endpoint for a RDBMS (MySQL database)

    - by Ankur
    I am doing (want to do) some experiments with Linked Open Datasets particularly those put out by governments. I have a RDBMS (more specifically MySQL). I designed it with semantic web ideas in mind i.e. I have a information stored as objects, predicates and classes which define objects. In turn all objects are related to each other though statements of the form subject -- predicate -- object (where the subjects are from the objects table). I want to be able to query other RDF triple stores from my application and let other triple stores query my data. Is it possible to "set something up" so that this is possible? I have looked at Jena. Using Jena seems to mean I have to it as a storage application rather than MySQL - the only problem with this is that I include a new concept called a category (which I don't think is part of the semantic web languages). I will use categories to help with displaying information (they don't have any other meaning) but using Jena seems to mean that I can't organise predicates under categories for more convenient viewing. I am using Java so a JAVA API is preferred. It's also possible I misunderstood the purpose of Jena, and maybe that can be of use, but I am not sure how. I am sure four days from now this question will seem rather silly, but at the moment I am somewhat confused about how to proceed.

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  • ORA-12560: TNS:protocol adaptor error after delete one database

    - by malihe
    i have oracle11g desktop. For my project I create 3 databases via configuration assistant tools. Then I delete one of them and after this I have the error: ora-12560. By mistake both of my databases have the same pasword, for example: when i want to connect one of these data bases with system user, i have one pasword and perhaps the databases dont know connect which one. I start all services set oracle_sid=orcl. I run lsnrctl tnsping check tansname.ora & my listener.ora and I logon with sysdba@oracle_sid but i have this error again pleas help me tnx

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  • Database Schema for Machine Tags?

    - by Gabriel
    Machine tags are more precise tags: http://www.flickr.com/groups/api/discuss/72157594497877875. They allow a user to basically tag anything as an object in the format object:property=value Any tips on a rdbms schema that implements this? Just wondering if anyone has already dabbled with this. I imagine the schema is quite similar to implementing rdf triples in a rdbms

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  • Postgres vs Firebird

    - by Tedi
    I'm looking to use either Firebird or Postgres in my next development project ... largely because both are available under a BSD-like license. I found a great comparison of the two database at http://www.amsoftwaredesign.com/pg_vs_fb But this comparison is a good 2+ years old and both databases have come a long ways since. Does anyone mind updating the comparison table to be relevant for the current versions of both Firebird and Postgres ... or have a link to a site that does a good recent comparison between the two database?

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  • Error on Access database: Permission denied: 'CreateObject'

    - by elixireu
    Hi, I am migrating a website over to a new server, its in ASP and uses several Access databases, the site and CMS can read, display the data, and even edit and update existing data entries, but when I want to add a new entry, I get an error... Microsoft VBScript runtime error '800a0046' Permission denied: 'CreateObject' /padp2010d/ads_tradetracker.asp, line 11 There seems to be no passwords on the databases, I have set up and tested the ODBC Data Sources and they are working fine. The code or line that is causing the problem is... <% Dim Mail, strPath, strHost, Upload Set Upload = CreateObject("Persits.Upload") Upload.IgnoreNoPost = True ' Generate unique names Upload.OverwriteFiles = False ' Limit file size to 500000 bytes Upload.SetMaxSize 500000, True ' capture an upload and save uploaded files (if any) in temp directory Upload.SaveVirtual "\pa\images\advertenties" Upload.Save ' Use session ID as the new file name NewName = Session.SessionID The line 11 is Set Upload = CreateObject("Persits.Upload") If anyone could help that would be great. Could it be a Permission setting? Im a complete novice with ASP and Access! Thanks

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  • Doctrine-CLI database creation issue.

    - by gokujou
    I have Doctrine setup in my Zend Framework application and I built my schema YAML file. But when I tell Doctrine to build the tables it says it does but it doesn't actually make them. It creates the models, and will create the DB but it will not populate the DB with the tables and throws no errors. Does anyone have a guess or know why this is not working? Thank you.

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  • POS Desktop Application using DB or Localfiles ? using WPF

    - by Panindra
    I am planning to build a POS Application for my shop. I have enough knowledge to build the application using DB and also using local files( system.IO - binary files ) to store and access the data for my application. But , i have no deployment experience and confused in choosing data storing option. Database using MDF may be good option ( may ease plenty of coding ) but i don't want to have SQL server on my desktop. as i am using WPF for building , my concern is that my application may get slow due to server response and design rendering of WPF. Then i tried to use only local data (binary files) to store the data and retrive using class and objects. but this coding is taking lot of time , so in the middle of the process i struck in the dilemma of going back to Database . Please help , for performance wise whic one is better . and in Practical World ,in professional applications which one is widely using .. please give suggestions ..

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  • Using SMO to call Database.ExecuteNonQuery() concurrently?

    - by JimDaniel
    I have been banging my head against the wall trying to figure out how I can run update scripts concurrently against multiple databases in a single SQL Server instance using SMO. Our environments have an ever-increasing number of databases which need updating, and iterating through one at a time is becoming a problem (too slow). From what I understand SMO does not support concurrent operations, and my tests have bore that out. There seems to be shared memory at the Server object level, for things like DataReader context, keeps throwing exceptions such as "reader is already open." I apologize for not having the exact exceptions I am getting. I will try to get them and update this post. I am no expert on SMO and just feeling my way through to be honest. Not really sure I am approaching it the right way, but it's something that has to be done, or our productivity will slow to a crawl. So how would you guys do something like this? Am I using the wrong technology with SMO? All I am wanting to do is execute sql scripts against databases in a single sql server instance in parallel. Thanks for any help you can give, Daniel

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  • How to design this simple database?

    - by Vafello
    I have 2 tables - one storing user information (id, username, password) and the second one storing information about events (id, name, description, date, username(represents the user who created the event)). I would like to implement 'favourite events' functionality. This would allow the user to store his favourite events and later display them in a list. I am not sure how to implement this in terms of design. I need a simple solution. Something like storing the IDs of favourite events in a field in the user table. I am using mysql and php. Can anyone point me to the right direction?

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  • authorise user from mysql database

    - by Jacksta
    I suck at php, and cant find the error here. The script gets 2 variables "username" and "password" from a html from then check them against a MySQL databse. When I run this I get the follow error "Query was empty" <? if ((!$_POST[username]) || (!$_POST[password])) { header("Location: show_login.html"); exit; } $db_name = "testDB"; $table_name = "auth_users"; $connection = @mysql_connect("localhost", "admin", "pass") or die(mysql_error()); $db = @mysql_select_db($db_name, $connection) or die(mysql_error()); $slq = "SELECT * FROM $table_name WHERE username ='$_POST[username]' AND password = password('$_POST[password]')"; $result = @mysql_query($sql, $connection) or die(mysql_error()); $num = mysql_num_rows($result); if ($num != 0) { $msg = "<p>Congratulations, you're authorised!</p>"; } else { header("Location: show_login.html"); exit; } ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Secret Area</title> </head> <body> <? echo "$msg"; ?> </body> </html>

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