Database design is the process of specifying the logical and/or physical parts of a database. The goal of database design is to make a representation of some "universe of discourse" - the types of facts, business rules and other requirements that the database is intended to model.

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Same field but different contents

I'm building a database for a divination system. Just to make it easy, I'll explain it in terms of the i ching. Every element of a hexagram is a different table. There's one for yin and yang, one for ...
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3k views

is it possible to create a form in the intranet that can be stored in a database?

I am trying to create a form for my companies intraNet site. The idea is as follows: An employee wants to make a purchase, so they will go to the appropriate page in the intraNet They will fill out ...
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593 views

Good reason to denormalize?

I have a database with about 40-50 tables. All but 5 are part of a giant hierarchy of 1:M relationships that all point back to one solitary parent (call it "Project"). Each table is joined to its ...
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1answer
561 views

Model for Distributed Database [closed]

I want to design a model for a distributed database solution. Are there appropriate tools and approaches? How to include stereotypes for (horizontal) fragments?
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1answer
202 views

Use multiple columns for location or supertype/subtype?

Given an Equipment entity, it has a location, generically called Whereabouts. This could be a reference to: a User entity (the employee who will use and be responsible for the eqipment for the next ...
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3k views

Are there DBMS that allow a Foreign Key that References a View (and not only base tables)?

Inspired by a Django modeling question: Database Modeling with multiple many-to-many relations in Django. The db-design is something like: CREATE TABLE Book ( BookID INT NOT NULL , BookTitle ...
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2answers
236 views

Both Primary and Foreign Key Needed on Table?

Someone recently asked this question: There are two tables: Deal and DealCategories. One deal can have many deal categories. So the proper way should be to make a table called ...
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3answers
2k views

Is using multiple foreign keys separated by commas wrong, and if so, why?

There are two tables: Deal and DealCategories. One deal can have many deal categories. So the proper way should be to make a table called DealCategories with the following structure: DealCategoryId ...
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4answers
1k views

Table with contacts: how to differ between people and organizations?

In several projects, I've seen the same problem pop up. But so far, I have not found a satisfying solution. Here's the issue. I need a table with contacts. These 'contacts' could be individual people, ...
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748 views

How to translate high level entity relationship into schema

According to the following articles written by Dr. Chan, we can describe high level entity relationship. (see page-10,11 of doc-A and page9 of doc-B) •doc-A) English Sentence Structure and ...
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2answers
736 views

Recommendations for building a big search engine

I am creating a image search engine that would probably have millions of images tagged with keywords. Basically it would be something like Google Image search. So I want to ask for any tips on ...
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1k views

How to store many smallish time-series in a relational DB?

Input Data Multiple Tests Beds generate measurement data of various complexity. In it's most basic form, not considering any meta-data, one measurement on a Test Bed will be a small (1 - a few ...
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6answers
798 views

What is the best database design for this situation?

I'm working on building a business application for my company and struggling to pick the most appropriate database design for a particular situation. Let's say I have the following entities: ...
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613 views

Database Design Advice for Expert Systems - Rule Based Systems

Expert Systems are a branch of Artificial Intelligence. These systems try to capture knowledge of Experts via set of rules. Most of the rules are stated in natural language. But they need to be ...
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2answers
177 views

A Huge Database: Picking the right schema and data model

We want to store some genomic variant data but there are some problems, more important ones like problem of the data's immense size and variability. 1) Variant data can be huge. For example, a single ...
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1k views

how to set/change the font style in database?

This question may be duplicate with another but my question is this. I want to set or change the font style in header of table (like hindi font or any other) of database. I am using sql server 2008 ...
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70 views

Database design problem: where to put UNIQUE constraint

I have the following three tables: Form ----------- formId INTEGER PK name NVARCHAR(50) NOT NULL Block ----------- blockId INTEGER PK name NVARCHAR(30) NOT NULL ...
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2answers
1k views

Which is better for long term database scalability: adding columns or having key/value store

For application, which has few (5-10) settings at the moment but will have a lot more (up to 100) in the future which would be better approach: to add new columns to settings table every time new ...
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1answer
799 views

How to design database for tree view with an infinite depth

I am trying to combine C# and SQL2005 for an application which need to have tree view control. One of user requests is to that tree view can user friendly grow into infinite dept of child nodes. That ...
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2k views

Looking for example design of using an SQL database as a queue for throttling web service requests of multiple users

I'm designing a system for multiple users to queue their requests to a web service which takes requests such as creating new entries, changing entries, requesting data. Many of the web service calls ...
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1answer
259 views

Write Access Client App for SQL Server 2005 Backend [closed]

I'm writing an inventory/payroll system, and I'm storing all the records on a remote server running SQL Server 2005 on Windows Server 2008 R2. I was wondering how I could start writing forms(very ...
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2answers
960 views

schema analyzer tool [closed]

I am currently using TOAD to connect to the database. I have around 20 tables that I have been asked to analyze ( I am new to project ). I think the first place to start is to understand the relation ...
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2answers
4k views

What are the limitations of Toad for SQL Server freeware? [closed]

I just downloaded the freeware version of Toad for SQL Server. Toad's download site says: "the Freeware edition has certain limitations, and is not intended to be used as a TRIAL for the Commercial ...
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4answers
1k views

Database design: how to handle the “archive” problem?

I'm pretty sure a lot of applications, critical applications, banks and so on do this on a daily basis. The idea behind all that is: all the rows must have a history all links must stay coherent it ...
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1answer
859 views

How do you query supertypes to get subtype data?

I'm a bit of a DBA newbie here (coming from a programming background having to fill the role of a DBA), so please excuse by blantant and somewhat basic ignorance. Using a simple relationship between ...
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2k views

Weak entity and one-one or many-many relationship

In Entity Relationship Model, can the supporting (or identifying) relationships of the weak entities be many-many or one-one rather than many-one? Suppose I have a customer entity (C), a video entity ...
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What is a common way to save 'debit' and 'credit' information?

I'm working on an accounting system, and for each transaction I need to save if this is either debit or credit. I can think of two ways (MySQL database): METHOD 1 Amount (decimal) Type (enum, ...
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745 views

barcode inventory design - transaction or master?

I am building a inventory software for mobile phone retailers. There are several things confuse me. Ok, we have: Product Product Attributes Barcode Stock In Batch (Purchases/Return, etc) Stock Out ...
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463 views

mysql picasa like photo tags store and query [closed]

I want to make a photo website, allow users to upload photos and write 1-10 customs photo tags, like picasa. I use mysql. Tags could be words or short sentence, but total length can not over 80 ...
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4k views

How costly is opening and closing of a DB connection?

How CPU intensive is opening and closing of a DB connection (for a web app) in MySQL ... when the DB software is on localhost? ... when the DB software is on another machine?
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1answer
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Database Design: Linking 'vague' entries to associations?

Experienced developer, inexperienced DBA here. I'm currently working on a project that lets users input the names of freight vehicles for particular packages. Eg: Company: White Star Line Vehicle: ...
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1answer
156 views

Is a year-to-date dimension the same as a time dimension?

If I have a table such as...: YYMM | Sales ------------ 1201 | 10 1202 | 20 1203 | 30 1204 | 40 ... then I might describe this as having a time dimension. If I wanted to calculate a year-to-date ...
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2answers
7k views

How can you have two auto-incremental columns in one table?

I have a MySQL table that contains information on invoices of a company. However, this company has two branches, and each of them has a unique invoicing sequence; a "Serie A" and "Serie B", so to ...
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Data type for currency 'type' column, e.g. usd, cat, etc.

I am setting up a MySQL database for accounting software. One of the fields is to save the currency used for each transaction. What field type would you recommend? Details: No more than 10 different ...
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218 views

Is there a name for this “restricted one to many” relationship? Can it be enforced in the DB?

In an application I'm working on, we have a kind of "restricted one-to-many" relationship. I'm wondering if this has a name, and whether it's possible to enforce at the database level. A standard ...
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1answer
366 views

Design question about student assessment data

I am designing a relational database in Filemaker Pro that will be tracking assessment data for students in after school tutoring programs. Depending on the student's grade level and skill set, each ...
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3answers
137 views

Optimisation Newbie: How much of a 'sin' is redundancy?

I've been developing for a while, but never really had to deal with DB/scaling issues before. That's suddenly changed and I've found myself in the deep end. I have 2 SQL tables, as such: VOTES ...
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135 views

ERwin Data Modeler Support

For the sake of not asking 5,000 questions here; are there any reliable sources of information about ERwin? I have to use it for a course and I have been unable to find any website or documentation ...
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1answer
411 views

Normalization: Should common columns of two tables be pulled out into a third table?

Should I further normalize my current design to eliminate redundancies? I have the following tables: empl: standard user table empl_cat: employee "category" empl_admin_cat: administrative ...
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4k views

Handling growing number of Tenants in Multi-tenant Database Architecture

Handling a modest number of customers (tenants) in a common server with separate databases for each tenant's instance of the application is relatively straightforward and is normally the correct way ...
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4answers
219 views

MySql Database solution for specific web app problem

Well, I need to create a comment system for posts that people add to my web app. This web app is just like facebook or myspace posts. Users add posts and people can comment on them. But the problem is ...
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161 views

Human relations between users

I'm involve in a development of a tiny Social Network where users must be able to establish relations between them and also have permissions over contents. For a example: I add one user as my friend ...
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2answers
482 views

Managing features for a real estate agency [duplicate]

I have a database table real_estate where the basic information is held (id, status, sku, address, building_type, sales_status) and now I want to attach features to that real_estate table. The data ...
2
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1answer
140 views

One table or several tables?

I have several types of writings: articles, projects, reviews, etc. I have a table containing paragraphs (fields id (INT) and partext (TEXT)). Each writing consists of several (ordered) paragraphs. ...
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452 views

City Distance Map Database Design

Well I am just a db beginner, I want to design something like this I want to keep simple as possible, well I will enter all values[Cities, Distance etc.,] manually, because my cities are limited. ...
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4answers
8k views

Supertype/Subtype deciding between category: complete disjoint or incomplete overlapping

I'm building an inventory database that stores IT hardware, such as desktop computers, laptops, switches, routers, mobile phones, etc. I'm using supertype/subtype pattern, where all devices are stored ...
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2answers
394 views

What is the name of this schema pattern

Its been a few years... but I've run into a problem-set that reminds me of a schema design pattern and I'm trying to recall the details. Essentially, the pattern consists of one database which is 3 ...
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0answers
302 views

How to seperate sensitive data in database(MySql) [closed]

I need to design a database that will contains information about personal disease of users. What can be the approach in order to implement the columns of the DB's tables: encrypt the information, ...
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1k views

Model a family tree database in Access 2007

I designed my database with the intention of implementing it with MySQL, but have now decided to implement it in Access 2007 using form and subforms. While creating my UML diagram, I realised I have ...
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719 views

mysql products db design

I am building a products site with php and mysql(no shopping cart). I have 400k products, the main site with 2 methods for query. query for products types, all the query by menu, cloud tags (no ...