What's the best way to store versioning when writing a Wiki application?
I'm writing a wiki application which needs searchable version conrol. What's the best data model for this? I'm writing it in Django, not that that matters much. ...
data-modeling
What is the international format for telephone numbers
Is there a format for phone numbers which all numbers will fit into? (something that is more flexible than 3 numbers for the area code and 7 numbers for the rest) ...
Modeling atomic facts in a relational database
I want to record what various sources have to say about a historical figure. i.e. The website Wikipedia says that Susan B. Anthony was born February 15, 1820 and her favorite color was blue The book Century of Struggle says that Susan B. Anthony was born on February 12, 1820 and her favorite color was red The book History of Woman's S...
Modelling Users, Groups, Portfolios and Media using an MVC Approach
I am creating a simple design for a social-networking site using the MVC paradigm(in CakePHP) for a project, I have a table called Users which stores all the User Details, I have a Groups Table which stores all the Group details, the relation between these 2 models is has and belongs to many, then I have a group_portfolios table which st...
There is probably a name for this. Please re-title appropriately.
I'm evaluating the idea of building a set of generic database tables that will persist user input. There will then be a secondary process to kick off a workflow and process the input. The idea is that the notion of saving the initial user input is separate from processing and putting it into the structured schema for a particular app...
Denormalising in Data-Object model
I'm playing around with the .NET Entity Framework, and my first task is to populate a grid, from which single objects are chosen for editing. My prior code simply calls a DB view, which uses joins to give me a denormalised, human readable display record. Now, building an OR mapped model, I come to a choice. Do I add my view, or should...
Is there a tool to create MySQL database model from an existing MySQL database?
I am looking for a piece of software to allow me easily create the database mode for an existing MySQL database ...
Thinking in AppEngine
I'm looking for resources to help migrate my design skills from traditional RDBMS data store over to AppEngine DataStore (ie: 'Soft Schema' style). I've seen several presentations and all touch on the the overarching themes and some specific techniques. I'm wondering if there's a place we could pool knowledge from experience ("from the...
Entity relationship modeling: how to implement entity "roles"?
I've done a bit of reading on data modeling recently and have a question about roles that an entity may play. Consider a simple case where you've got a Company, and a Company can be a Supplier, Customer, Distributor, etc. or a combination of these roles. So company X might be both a Supplier and a Customer. Down at the data level you ...
How to model this multiple inheritance relationship with a RDBMS?
I'm looking at this data model I've come up with and not feeling comfortable. I've changed the entity names so it (hopefully) makes more sense. In any event, how would you model the following? I have 3 entities. GovernmentCustomer, PrivateCustomer, PublicCustomer. Private and Public Customer are both CorporateCustomers. Corporate and Go...
DB Design Question
I am designing an Org Chart, model is almost ready and simplified a bit for clarity here. OrgUnit (OrgUnitId, Name, ReportsToOrgUnitId, ...) OrgUnitJobs (OrgUnitJobId, OrgUnitId, JobName, ReportsToOrgUnitJobId, ... ,IsJobGroup) Employee (EmployeeId, ........) OrgUnitJobEmployee (OrgUnitJobId, EmployeeId, AssignedDate, .....,) so I wan...
Modeling entities for specific applications - Entity Framework
Hi, I have 2 applications: Manager UI - Which should be able to create a user with all its fields (username, email, age etc.) and display them. Core component - which only need the UserId and Username field, and need to be very performant. It also shouldn't be able to write to the database. It seems I need 2 different models, one for...
What are design patterns to support custom fields in an application?
We develop a commercial application. Our customers are asking for custom fields support. For instance, they want to add a field to the Customer form. What are the known design patterns to store the field values and the meta-data about the fields? I see these options for now: Option 1: Add Field1, Field2, Field3, Field4 columns of type...
e-shop implementation: Status for Orders?
Hello Again my fellow programmers out there, I'm designing and programming from scratch a online shop. It has a Module to manage "Orders" that are recieved via the frontend. I'm needing to have a status to know whats happening with an order in s certain moment, let's say the statuses are: Pending Payment Confirmed - Awaiting shipment...
Good resources on e-shop, e-commerce store Software Design?
Hello All, I'm designing an online store myself from scratch and I' really missing some valuable rources about the common problems and solutions found in designing and implementing a s-shop/e-commerce system Do you know any valuable resource about this I could read (online/book, blogs,etc). Any recommendation? greetz Guillermo ...
Which type do I use to represent an arbitrary blob in Java?
I have an application that may receive data via various methods and in various formats. I have pluggable receivers that somehow acquire the data (e. g. by polling a mailbox, listening for HTTP requests, watch the content of a directory etc.), associate it with a MIME type and then pass it on wrapped like this: public class Transmission ...
Database structure for master data selectively overridden per customer
For this question, consider an application using a multi-tennant database with modeling of manufacturers and models. If we're talking about cars then the manufacturers would be Ford, Chevrolet, BMW, etc. and the models would be F-150, Camaro, and M3. Relationship of model to manufacturer is many to one. Data for each tenant is separ...
Data Model tools for DB2
I have created a Database in DB2 and tables with relationships. I would like to create a ER diagram based on my database design in DB2. MS SQL has a facility to create ER diagrams from DB schema, but DB2 doesn't seem to have one, at least to my knowledge. Any one know of any open source tools/facility within DB2 itself for this? ...
Data Modeling - how to handle two, dependent "status" columns?
I've run across something that's bugging me just enough that I wanted to come here and seek out a sort of "best practice" type of advice from you guys (et gals) I have a table in my model, let's call it prospect. Two separate external systems can provide an update for rows in this table, but only as a "status" of that record in those r...
domain inheritance to relational db - looking for a working db model
Hello: The focus of this question is primarily to develop a relational db scheme given the object model here. This part of the system is concerned with time based allocations made by Resources (different flavors of Employees & Contractors) to Activities (either a Project or an Account). Data entry is weekly, and the domain model must v...