I have a sheet (let's go with wines as an example) that lists every bottle of wine in my cellar, when I bought it, how much I paid etc. There's a column that describes the wine in comma-separated tags such as "Fruity, White". I've created a pivot table from that data, with the description as a filter column. However I can't filter it b...
We create a output document (based on a template) to send to a customer for each product they buy. Templates differ per product (many products to one template), but currently all customers share the same templates 1) PRODUCTS ---------------- PRODUCT_ID (PK), TEMPLATE_ID (FK) 2) TEMPLATES ------------ TEMPLATE_ID 3) CUSTOMERS --------...
Don't be scared of the extensive code. The problem is general. I just provided the code to understand the problem better. I am trying to find out a standard approach of manipulating tables with many-to-many relationships. And I am almost done. Here Teacher and Course have M:M relationship. I have designed my classes as follows: Teacher...
Hi People. I'm trying to solve the relational model in order to make a Django app. I't will be something like a McDonald's crew scheduler. I mean the grid with colored pins marking who will be working at a given hour a given weekday. I did try to Google out some example, but I didn't find anything. I need some theory/bibliography in o...
Do you guys know, how we can convert XML Schema to relational model? What are the steps involved? More precisely, How can we figure out what the table names, columns names and the relationships on those tables, going to be like on relational model by looking only at the XML Schema? If you have any tutorial links, examples then please sh...
I know, relational database is a database where fields in one table are linking to rows in the others, something like this. But I can't understand what does it mean for me as a web developer! As I know, a query with joins and nested select can reduce perfomance (especially drupal-style queries with dozens of joins). Even more, any quer...
Hi! I have some relational MySQL database with dozens of tables... My query is 1000 ft long and selects data from almost all the tables... I also have my 'main' table, and all other tables are referring to that one. When I enter one row in my main table and when I create all relations for that row in other tables my query works fine. How...
I have a requirement to store all versions of an entity in a easily indexed way and was wondering if anyone has input on what system to use. Without versioning the system is simply a relational database with a row per, for example, person. If the person's state changes that row is changed to reflect this. With versioning the entry shou...
Can anyone suggest resources that take a mathematical approach to relational databases? Essentially relational algebra I'd guess. I have a mathematics background and now work a great deal with databases and would like to close the gap. ...
Background: today, an issue arose while using SQL Server Reporting Services. It seems that SSRS drop-down parameters in the report viewer don't allow you to indicate a (null) option so that you can see a report where that parameter is null. Basically, table A is a table nullably referencing table B; since the report uses table B to popul...
I'm trying to find a nice way to store word compositions of the following form: exhaustcleaningsystem exhaust cleaning system exhaustcleaning system exhaust cleaningsystem The combinations are given by a default per case. Every word in a composition is stored as a unique row in table 'labels'. labels id value --------------------...
What are the pros/cons of de-normalizing an enterprise application database because it will make writing reports easier? Pro - designing reports in SSRS will probably be "easier" since no joins will be necessary. Con - developing/maintaining the app to handle de-normalized data will become more difficult due to duplication of data and ...
Hello, I'm currently working on an ASP.Net MVC project for a software engineering class. My goal is to create a small online game rental system. I currently have a 3 tables, Movies, Games and Registrants; and I'm using LINQ-to-SQL to define each of these tables as classes for my model. So far I've created models for Movies and Games, ...
How can I get data from a relational database into RDF? ...
I am creating a C++ application the uses a MySQL database. I would like the application to create an account for itself, if possible. I have not found a method to do so. Everytime I port my application, I forget the set up sequence. The current set up sequence requires creating an account in MySQL for the application to use. Once ...
I'm coming from a MySQL background, and I'm interested in document-oriented databases, specifically CouchDB. One of the things I'm interested in is data integrity. How do document-oriented databases handle this? For instance, in RDBMSes, there are ways to prevent duplication of records, or guaranteeing that if you have one bit of informa...
Hello! This is my first time I am trying to make something seriously with relational db in MySQL and some kind of CMS created in PHP with CodeIgniter. I came to the part where I have to insert some data in few many-to-many related tables. In my code everything works fine (well, with just few minutes of testing), but I need some help with...
I am trying to use Microsoft Sync Framework for syncing 2 SQL Server 2005 database (server and client). There are multiple tables in the database with lots of foreign key relation between them. I am using SyncOrchestrator to synchronize the two databases. string clientConnectionString = "<connection string>"; string serverConnectionStri...
Hi there, I am looking into the best ways for storing surveys to a database with Rails. I have checked out this great Smerf Survey Plugin for Rails which stores surveys into a Relational Database with the following tables: smerf_forms: name, code smerf_forms_users: user_id, smerf_form_id, responses (as text) smerf_responses: smerf_f...
Hi..Im trying to figure out this HABTM relationship issue to store in the interests of users within my database. The interests table has a list of different interests with id and name (i.e: id=1 , name = 'Music') I have a users model => user.rb has_and_belongs_to_many :interests and an interests model => interest.rb has_and_belongs...