For questions about database design.
1
vote
0answers
28 views
Bayes filtering and data storage with expansive data sets
I am looking to write a Bayes filter that will act as an indicator of topic for a number of topics with a variable number of sources. Given a really big number of RSS feeds and here really big might ...
0
votes
3answers
124 views
Should lookup tables enumerating strings have an integer primary key?
When I learned relational databases, the prof said that one would "almost always" want an artificial int as the primary key in a table, but did not specify what the exceptions are. At some time I ...
-4
votes
0answers
37 views
DB design for fees management [closed]
I am doing a project in Cakephp where we need to manage fees of students.
Different kind of students may have different fees. Some students get discount too.
I don't know how to create db. Can ...
0
votes
1answer
73 views
What is a good design for a container, assignment and items
------------- 1 * -------------- * 1 --------
| Container |--------| Assignment |-----------| User |
------------- -------------- --------
^ ...
2
votes
3answers
140 views
Using a database for each module in a system [duplicate]
I was reading this question:
I was trying to standardize and modularize some functions (Email
Management Module, CMS Module & etc) by implementing a 3-tier
architecture concept where each ...
2
votes
2answers
349 views
Why OTServs have an item cloning problem if the server crashes? [closed]
OTServs are open source MMORPGs with a huge community. Mostly all of them have a serious problem: if the server crashes, people can clone items. This is a dirty trick that can be executed because the ...
1
vote
1answer
38 views
NoSQL (Azure Table Storage) RowKey design for ordered data
I store large quantities of GPS data in storage tables. Each partition can reach up to 1 million entities. Each GPS entity that is inserted into the table is actually sequential to the previous data ...
4
votes
5answers
407 views
Why is the usage of string keys generally considered to be a bad idea?
This has been bugging me for a while. Most of the time, when it comes to storing data in structures such as hashtables, programmers, books and articles insist that indexing elements in said structures ...
1
vote
1answer
41 views
Azure Storage Table design with multiple query points
I have the following Azure Storage Table.
PositionData table:
PartitionKey: ClientID + VehicleID
RowKey: GUID
Properties: ClientID, VehicleID, DriverID, Date, GPSPosition
Each vehicle will log ...
6
votes
1answer
64 views
Ledger or log design for a point-based system?
Right now creating a new service that will integrate into our company's existing platform. The service will be responsible for tracking "points" that a user can generate over time through certain ...
1
vote
1answer
112 views
A multi tenant data architecture
We are at a planning & redesign stage of our loyalty card application. As it is understood it will be a multi-tenant application. And I need to take your thoughts. Here are the some key points we ...
1
vote
1answer
119 views
Table scaling with partitions or with separate databases?
Let's say I have a table (let's call it BigTable) which could experience 5,000,000 INSERTS per day (with possibly just as many SELECTs). Each row inserted is about 50kb.
These daily INSERTs are ...
3
votes
2answers
95 views
Does this situation call for well specified associations, single table inheritance, or polymorphic association?
I'm building a web-app where users can keep track of who owes whom money.
I have users and debts.
Given a user I want to be able to find out all the debts to other users, and all the loans to other ...
3
votes
4answers
446 views
Better way of storing key-value pairs in the database?
I have a C#/SQL Server program that sometimes needs to store data. The data could be a response from a web service, a result of a database query, or any number of other things. There's no way of ...
0
votes
2answers
111 views
How to improve database schema with different n:m and 1:n associations between users/tasks/comments/attachments
I'm trying to build a database for an upcoming Ruby on Rails webproject.
There will be 4 tables minium: tasks, users, attachments and comments.
And 1 table to join the n:m relations (tasks <-> ...
3
votes
3answers
141 views
How should I represent an enumerated type in a relational database?
I am working on developing a relational database that tracks transactions that occur on a device I'm working on for my company. There are different types of transactions that could occur on the ...
2
votes
2answers
76 views
Should database-models (conceptual or physical) be reviewed by DBAs?
Where I work, new applications that are being developed that will use their own relational database, must have their database-models (conceptual, then physical ) reviewed and aproved by DBAs.
Things ...
3
votes
6answers
251 views
Should a database table(s) structure match its intended data structure(s) in the logic?
This question branches out of this question, What are the differences between algorithms using data structures and algorithms using databases?.
The General Question
Should a database table(s) ...
2
votes
4answers
194 views
(Dis)advantages of datetime vs. long in globally used applications [closed]
I am currently designing a web/mobile application the bulk of whose users will be distributed across the different U.S. time zones with a potential of scaling up to other countries and time zones as ...
8
votes
7answers
652 views
Design Parts DB
I'm developing a tool that handles (electrical) parts. The parts can be created, viewed, modified, deleted, grouped and so on...
In order to make this question useful for future visitors I like to ...
1
vote
2answers
282 views
Alternatives to sql like databases [closed]
These days computers usually have 2GB or 4GB memory.
I like to use some secure client server model, and well an sql database is likely candidate.
On the other hand I only have about 8000 records, ...
0
votes
1answer
116 views
Storing revisions of a document
This is a follow up question to my original question. I'm thinking of going with generating diffs and storing those diffs in the database 'History' table.
I'm using diff-match-patch library to ...
2
votes
2answers
602 views
When should we use weak entities when modelling a database?
This is basically a question about what are weak entities? When should we use them? How should they be modeled?
What is the main difference between normal entities and weak entities? Does weak ...
1
vote
1answer
152 views
NoSQL as file meta database
I am trying to implement a virtual file system structure in front of an object storage (Openstack). For availability reasons we initially chose Cassandra, however while designing file system data ...
3
votes
1answer
157 views
Database Schema Usage
I have a question regarding the appropriate use of SQL Server database schemas and was hoping that some database gurus might be able to offer some guidance around best practice.
Just to give a bit of ...
6
votes
1answer
477 views
self referencing tables, good or bad?
Representing geographical locations within an application, the design of the underlying data model suggests two clear options (or maybe more?).
One table with a self referencing parent_id column
uk - ...
-2
votes
3answers
188 views
What makes Java so suitable for writing NoSQL Databases
Looking at this page that aggregates the current NoSQL landscape, one can see that the majority of these projects are written in Java.
Databases are complex systems software dealing with the file ...
10
votes
7answers
546 views
Are there examples of non CRUD approaches?
I'm a programmer but also have worked as an archivist. As archivist it's a lot about keeping data.
I often get into arguments with colleagues when it comes to operations on data. I don't like the U ...
4
votes
2answers
220 views
Which design better when use foreign key instead of a string to store a list of id
I'm building online examination system. I have designed to table, Question and GeneralExam. The table GeneralExam contains info about the exam like name, description, duration,...
Now I would like to ...
2
votes
1answer
95 views
Designing persistence schema for BigTable on AppEngine
I have tried to design the datastore schema for a very small application. That schema would have been very simple, if not trivial, using a relational database with foreign keys, many-to-many ...
4
votes
3answers
250 views
Set modified date = created date or null on record creation?
I've been following the convention of adding created and modified columns to most of my database tables. I also have been leaving the modified column as null on record creation and only setting a ...
2
votes
2answers
113 views
how to model this relationship ? in ERD
I have three entities :
Technician
Vehicle
Repair
The question is how to model this in ERD? Knowing that a technician can repair multiple cars, and the same car can be repaired by one and only one ...
1
vote
4answers
249 views
Is data integrity possible without normalization?
I am working on an application that requires the storage of location information such as city, state, zip code, latitude, and longitude. I would like to ensure:
Location data is accurate
Detroit, ...
6
votes
4answers
203 views
Where ORMs blur the lines between code and data, how do you decide what logic should be a stored procedure, and what should be coded?
Take the following pseudocode:
CreateInvoiceAndCalculate(ItemsAndQuantities, DispatchAddress, User);
And say CreateInvoice does the following:
Create a new entry in an Invoices table belonging to ...
2
votes
3answers
546 views
Storing Attendance Data in database
So i have to store daily attendance of employees of my organisation from my application . The part where I need some help is, the efficient way to store attendance data. After some research and brain ...
3
votes
2answers
98 views
Best approach for saving highlighted areas on geographical map
I am designing an application that allow users to highlight areas of a geographical map using a tool that is like brush or a pen. The tool basically draw a circle with a single click and continue ...
9
votes
1answer
473 views
Classless tables possible with Datamapper?
I have an Item class with the following attributes:
itemId,name,weight,volume,price,required_skills,required_items.
Since the last two attributes are going to be multivalued, I removed them and ...
7
votes
5answers
404 views
Predicting advantages of database denormalization
I was always taught to strive for the highest Normal Form of database normalization, and we were taught Bernstein's Synthesis algorithm to achieve 3NF. This is all very well and it feels nice to ...
2
votes
1answer
292 views
Architecture for Social Graph data that has a Time Frame Associated?
I am adding some "social" type features to an existing application. There are a limited # of node & edge types. Overall the data itself is relatively small (50,000 - 70,000 for each type of ...
3
votes
2answers
445 views
Document-oriented vs Column-oriented database fit
I have a data-intensive application that desperately needs a database make-over.
The general data model:
There are records with RIDs, grouped together by group IDs (GID). The records have arbitrary ...
5
votes
4answers
162 views
Should I comment Tables or Columns in my database?
I like to comment my code with various information, and I think most people nowadays do so while writing some code.
But when it comes to database tables or columns, I have never seen anyone setting ...
-1
votes
2answers
446 views
Fitting it together, database, reporting, applications in C#
Introduction
Preamble
I was hesitant to post this, since it's an application whose intricate details are defined elsewhere, and answers may not be helpful to others. Within the past few weeks (I was ...
0
votes
1answer
147 views
Breaking 1NF to model subset constraints. Does this sound sane?
My first question here. Appologize if it is in the wrong forum but this seems pretty conceptual. I am looking at doing something that goes against conventional wisdom and want to get some feedback ...
5
votes
5answers
740 views
Configuration data: single-row table vs. name-value-pair table
Let's say you write an application that can be configured by the user. For storing this "configuration data" into a database, two patterns are commonly used.
The single-row table
CompanyName | ...
5
votes
11answers
2k views
Using XML as data storage
I was thinking about the XML format and the following quote:
“XML is not a database. It was never meant to be a database. It is never going to be a database. Relational databases are proven ...
4
votes
2answers
242 views
Proper Data Structure for Commentable Comments
Been struggling with this on an architectural level.
I have an object which can be commented on, let's call it a Post. Every post has a unique ID.
Now I want to comment on that Post, and I can use ...
0
votes
2answers
235 views
The limit of Int32 for Identity Column
This is just a consideration for a site am creating and for other big sites out there.
I am using Identity Column to store the ID of some of my tables and I have classes whose Id are decorated with ...
0
votes
2answers
269 views
Does there exist a design-pattern for this problem?
I have a big database of data which we can consider today's system. The data has a web front-end which allows my users to update the data. Let's call this "original solution"
When new users come in ...
0
votes
1answer
123 views
Would this data requirement suit a Document -Oriented database?
I have a requirement to allow users to fill in journal/diary entries per day.
I want to provide a handful of known journal templates with x columns to fill in. An example might be a thought diary; a ...
3
votes
3answers
326 views
Which aspect of normal forms do entity-attribute-value tables violate, if any?
I'm not asking if EAV tables are good or bad. I'm wondering if they are considered "normalized", and if not, why? If they aren't normalized, which normal form are they violating and why?
