The logical model and/or physical design of a database.

learn more… | top users | synonyms (4)

0
votes
2answers
107 views

Inheritance of unknown type at creation time

Say I have a table called People into which people are inserted from the moment they are born. Now lets say I want some subclasses of people based on their job. So there are also tables for Plumber, ...
0
votes
1answer
74 views

What does a CONSTRAINT have to do with my unique index?

I have to indexes on my table. The first was created by Django and the second by me. I'm not completely certain what the extra CONSTRAINT means in the first index and am wondering how I would change ...
0
votes
1answer
224 views

How to reference categories table in products table?

I am using modified preorder traversal algorithm to store product categories in database (like image shown above). But i don't understand how to reference it in my products table. Here is my products ...
0
votes
3answers
816 views

Database structure for hierarchical quiz?

I'm doing a personal project where I have a quiz with a number of boolean questions. Each question will have a two answer choices "true" and "false". Based on the selected answer, a new question will ...
0
votes
2answers
32 views

Report individual changes to data

I need to produce a daily extract on the individual changes to a dataset. So, there are 14 tables containing product and customer information and the extract must only show records from each table ...
0
votes
3answers
437 views

Autoincrement Primary Key For Constants

We are having an issue that is probably due to some poor design choice or lack of understanding of how to use primary keys. We have a simple constants table CREATE TABLE IF NOT EXISTS `constants` ( ...
0
votes
1answer
63 views

How can I quantify the business value of normalization?

My company is developing an internal application with a SQL server database which was started earlier by another developer. Now I am Looking at the model,the developer has stopped at 1NF. I proposed ...
0
votes
3answers
147 views

Database Design for Paper Submission System

I am learner of Database design, I want to design a database for a journal paper submission system in which one paper can be submitted by one or more author. I have initially two tables Author and ...
0
votes
3answers
202 views

Confused about Primary Keys, and Foreign Keys

Im brand new to database design and, I'm slightly confused about Primary Keys, and Foreign Keys and my database design. Context: I'm working on a database of museums and Categories will be one way ...
0
votes
1answer
28 views

Ensuring that 1 row has 5 specific records referencing it

Context: a TEST has many CASEs. Typical. However, the catch is that a TEST instance must have exactly 5 instances of CASE (1 to 5). I could do something like this: create table TEST ( ID ...
0
votes
1answer
97 views

Should there be a temporary table to hold Order and OrderItems? [closed]

After trying out a few open-source restaurant POS, I still couldn't decide if there should be a temporary to hold Orders and OrderItems? I was initially thinking to have temporary tables and ...
0
votes
1answer
134 views

Database structure for bonus system in MySQL

I have a problem with creating the structure for my database in MySQL as I'm new in creating databases. The problem is in this: there are three tables sellers, clients and bonus. Table sellers stores ...
0
votes
1answer
35 views

Separation of users columns in another table

I've got a quite a lot of columns on the users table and I have been cleaning it up recently. Now since I'm searching over the users I figured it would improve performance if I separated verification ...
0
votes
2answers
67 views

What database should I use? [closed]

I am writing a log analysis program in bash. As part of it, I am compiling a list of known errors, so that I can search and reference those errors as part of the known list. I originally was going to ...
0
votes
2answers
676 views

What's the use of assigning foreign keys on MySQL [duplicate]

Aside from indexing the value of the foreign key, what is/are the advantage of assigning foreign keys to databases? I've seen a lot of databases that does not assign foreign keys, but is relational by ...
0
votes
1answer
1k views

Parent/Child table design?

Lets say I have a table to hold Tasks and then I have a table to hold Sub Tasks, is it better to break Tasks and Sub Tasks into separate tables or keep them both in the same table with a possible ...
0
votes
1answer
486 views

Database revision needed for sports events database

This is not a code review but more of a database schema review. I have a sports events website that I am doing in my spare time. I need assistance with the database design. I am about 80% completed. ...
0
votes
1answer
200 views

Optimization for 100 GB Real-time info table

I have a table of device information feed which is filled by data from remote device units. There will be like 1000 units each sending an update per minute which will be stored as a row in that table....
0
votes
1answer
658 views

Problem creating database using default mdf and ldf path

I'm trying to create a database using the default paths on several SQL Servers at once. To achieve this I'm trying to use a script that should create the database on each server, however I've run into ...
0
votes
1answer
132 views

Creating and designing Air Trafic Control System [closed]

I'm having a class about Database management system, and the prof. gave us a project regarding Air traffic controller system, exact question is "Design and create a system which can manage ...
0
votes
1answer
38 views

SQL - Query on table creation, referential integrity

Please let us know what does the below definition means on table creation. CREATE TABLE A(w INT PRIMARY KEY); CREATE TABLE B(x INT PRIMARY KEY REFERENCES A(w) ON SET NULL) As per my understanding, ...
0
votes
1answer
170 views

Need some expert eyes to look at my schema

I am trying to make an online site for local movies. Will be written in PHP and will be using MySQL as the database. What I want is to create a mini IMDB type site, with movies, people(casts/crew), ...
0
votes
1answer
815 views

Best way to store country and city information

I always wondered what is more efficient between two. There is one "main" table where I store all user related informations. Also, there are two more tables, country and city tables. city table ...
0
votes
1answer
250 views

Foreign key double inheritance SQLITE

I'm designing a domotic system database and I'm trying to figure out how to represent two foreign keys. This is the cardinality I want. Consider 1...N Areas (rooms, halls, kitchens, etc.): Area 1 - ...
0
votes
1answer
87 views

Is array serialization always bad idea?

I'm making form-generating app in php. I have Widget table with type_id (html input) field, and I would like to add options field, like width/height, step, range, etc. Different widgets do have ...
0
votes
1answer
67 views

Which one is correct and optimized in sql?

Imagine that I have three entities (EntityA, EntityB, EntityC) that can have some images. So there are two ways: Make an image table for each entity. It means that EntityA has a image table named ...
0
votes
1answer
264 views

How to structure renting and sale as type of purchase?

I'm currently planning a database which involves two different types of Products that can be bought outright, or rented for a weekly or monthly amount. I'm just trying to figure out how to structure ...
0
votes
1answer
46 views

Table join inheritance

I create db with Person, Client, Employee, Manager, Developer. I'm interested what is the best way to put the data in tables. In which cases should programmer unite Client in table hierarchy with ...
0
votes
3answers
23k views

MySQL vs. Microsoft Access [closed]

I'm trying to aggregate about 500-1000 MS Excel files that deal with various small business issues (inventory, purchase orders, etc) and I'm currently trying to decide what kind of RDMS I should use. ...
0
votes
1answer
77 views

Fetching User Recent Status

I am running mysql with MyISAM storage engine to store user status(user updates data). To load user recent updates data i am using this query: $limit = 20; $uid = 3; SELECT * FROM userstatus WHERE ...
0
votes
2answers
780 views

Is a temporary table a good solution for importing temporary data into a database

i am facing the following scenario. I have a student database in which exam results are stored. Every now and then i get a list with the names of certain students for which i need to find out how well ...
0
votes
2answers
87 views

General table name for Person Inf

I was in a meeting with my boss and technical support leader and they asked me for a database model to a very simple application. That application requires: employees information, some location data, ...
0
votes
2answers
270 views

mysql forbidden database names

I was wondering whether there were a list of forbidden (reserved) database names in mysql. For instance, mysql is obviously one. But is there a determinated list? I don't want to cover 99% in my ...
0
votes
1answer
44 views

Help with designing a multi relational schema / domain model

I am in the process of developing a web application with asp.net MVC. I am using Entity Framework to make a connection to my database. I am having trouble with a specific concept in my program. I ...
0
votes
1answer
1k views

Benefits of using Staging Database while designing Data Warehouse [closed]

I am in process of designing a Data Warehouse Architecture. While exploring various options to Extract data from Production and putting into Data Warehouse, I came across many articles which mainly ...
0
votes
1answer
101 views

Archery League Database design [closed]

I'm fairly new with database desings (only worked on a couple of projects) and i kinda need some info on how to contruct the following. I need to keep stats for an archery league and the players. ...
0
votes
1answer
79 views

creating a historical database, need help making a decision

I'm working with 5 processes that take about 8 hours to run, during each 8 hour process, it changes its location at random times but in a specific order. There could also be all 5 processes running at ...
0
votes
2answers
4k views

Database partitioning - Horizontal and Vertical sharding - Difference between Normalization and Row Splitting?

I am trying to grasp the different concepts of Database Partitioning and this is what I understood of it: Horizontal Partitioning/Sharding: Splitting a table into different tables that will contain a ...
0
votes
1answer
68 views

What is the “proper” way to design a database architecture when entry counts belogning to different users may vary wildly?

To give a context; we are going rewrite our application in Django framework. The database that is being used by the old system at the moment designed very poorly, without any respect to methodology of ...
0
votes
1answer
446 views

Does my ERD account for my business logic

As part of my new and upcoming project, part of the business logic involves sending each and every one of my customers (assume they number in their 1000s) multiple (possibly customized) emails. Each ...
0
votes
1answer
2k views

How can you have a combined primary key for one table?

I have exactly the same question as posted here. But in my case I do not use MySQL but Postgres. Can this be done with Postgres? All things indicate I can not use a combined index in Postgres, so ...
0
votes
2answers
229 views

Additional fields or intersection table

I have a domains table and each domain belongs to a contact. Additionally you can assign 3 extra contacts with different roles admin, tech and billing ,those are not mandatory. My first thought was ...
0
votes
2answers
145 views

Configuration Table

Can someone explain what is the difference between a Configuration table and a Data table in a database? And how to design or implement Configuration table? I'm using MySQL and the requirement is to ...
0
votes
1answer
71 views

What do you call numerical coding systems that are left-aligned?

I'm writing an importing mechanism for the NAICS database. I have a few questions about this code-format. I've seen it before and I like it the setup. I'm going to ask some other questions about best-...
0
votes
2answers
152 views

To normalize or not

I'm scraping data from a website and they have pages for Users and Groups. The pages are pretty similar; id, name, description, created date, number of elements and custom background. They also have a ...
0
votes
2answers
210 views

Best way to handle temporary data

Say I have a table prices. Users can see the prices of this table (I'm simplifying it). Users also can send prices to the server, so the server is going to collect these data in another table (...
0
votes
2answers
669 views

Database design with multiple tables

I have a data structure as follows: Two main components: Projects and Results So I have a table called Project which has multiple fields as Id, Name, Title, StarDate, EndDate and many more which ...
0
votes
1answer
153 views

Two types of data, so two type of databases?

For a social network site, I need to propose a DB. The application is written in Java & will be hosted on VPS(s) initially. Broadly classified there is two type of data to be stored at backend: ...
0
votes
1answer
59 views

Creating groups and members [closed]

Is this a good idea to manage members of a group like so: *Assuming members can belong to one group and no other *Simplified model Group: name someid User: name ForeignKey(Group) state #...
0
votes
1answer
140 views

Create primary keys based upon higher-level entity in access?

Is it possible to have access create primary keys for items by appending a string to the primary key one level above it? I am trying to create an inventory management database for my company's server ...