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

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Designing table for document annotation with future columns

I am working on a web application that allows students/researchers to annotate PDF documents shallowly by (manually) counting interesting phenomena. Right now, there is a total of about 45 of these ...
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0answers
8 views

Time Series on Postgresql

I am developing a software that have a dataset time series like this: id_equip, Timestamp, Double v1, ..., Double v30 The size estimate is 5.000.000 rows by year and the time of response is very ...
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1answer
54 views

Storing Friendships: Should I use a multivalued column to retain Friend Identifiers?

Say I have a table UserFriendlist that has the columns: Id (set as Primary Key) UserId FriendListIds And let us suppose that it holds the following values: ...
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6 views

Maximum number of TEXT/BLOB columns per table/performance of table with many of them?

I've created a system that generically imports CSVs into a database table with metadata columns for keeping track of when a CSV record has been changed, and it allows filtering on CSV columns instead ...
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0answers
33 views

Chemical Availability Database Schema

Looking to create a database to track available inventory by lot number on a database. Raw Materials are received in batches with id #'s in units of pounds and pulled in different amount from those ...
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1answer
31 views

Altering column data SQL

I have a set of car data, one of the columns represents the registration year. I want to change this column to age. As the data is from 2010 I assume that the following statement should calculate the ...
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0answers
12 views

3NF For a Weak Entity with no non-Key attributes

Can a weak entity made with no non-key attributes be in 3NF? I'm making a db for an assignment, and I currently am struggling to figure this out, especially since I've introduced auto-increment ...
2
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1answer
66 views

Many to many between lots of tables?

TL;DR: How could I set up many-to-many relationship between that many tables and is it viable/recommended? Each body type has its own table Each car in each body type table can has several ...
2
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1answer
62 views

Unique key based on many-to-many pivot table

I have to manage artists and albums tables: | artists | | albums | | album_artist | +--------------+ +--------------+ +--------------+ | id | | id | | id ...
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2answers
43 views

How can I create a join on three tables, each from a different database?

Here is a simplified example of what I'd like to do: SELECT a.create_time, b.create_time FROM DOB.dob_state AS a JOIN numID.numID_history AS b ON a.create_time = b.create_time; I'd like to join ...
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0answers
22 views

Database design for different, but related, objects

I'm new to relational databases having enjoyed the flexibility of nosql to date. I want to store data about 'estimates'. An estimate takes a set of parameters that depend on which product it is an ...
2
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1answer
43 views

How do I guarantee inventory numbers are unique across all tables?

I have an assortment of physical objects which need to be inventoried and each type of object has it's own table. For two example objects, let's use 'swords' for the table containing different swords ...
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1answer
101 views

compare file-based systems and a relational database [on hold]

I don't know the exact difference of both can you please compare file-based systems and a relational database?
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1answer
22 views

Why does 3NF Normal form allow transitive dependency of prime attributes?

I'm just a beginner in Relational Design, When i came across the definitions of 3NF and BCNF. According to 3NF, Any non-trivial functional dependency X-> A shouldnt exist unless X is a super key or A ...
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2answers
777 views

How to build a table for a private messaging system that supports replies?

I'm writing a private messaging web application in PHP, the application allows replies such that when you view a message, you also get to see to what was that a reply to, and to what was that a reply ...
0
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1answer
183 views

How to setup sync between MongoDB and C# .NET Application

What is the best practice to synchronize a MongoDB remote database with a C# .NET App that would allow queries to be responded to within the local file system and update itself when there is a change ...
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1answer
27 views

Multiple references to another table, but I don't know how many

I have two tables in a database, folowwing this model: scientists : id (int) | name (varchar) | surname (varchar) | publications (int) publications : id (int) | fulltext (varchar) I would like to ...
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1answer
1k views

Allow access to enter data through forms, but not full database access

Using Access 2013 or Sharepoint 2013 is it possible to give someone access to data entry forms that work with a back end database whether Access database or Sharepoint SQL. But from everything I've ...
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0answers
12 views

How to create a table in access and automatically fills it with information from a query?

Is it possible if I create a table that will lookup for a value filtered from a query (consult), in this case is duplicated "Name"s from a Employees registring table and automaticly fills up that ...
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0answers
6 views

In a Registry Formulary (Table origin), how to show an image (Object ole) that is linked with the “Name” Collum in the table? [on hold]

I got in a table a Collum named "Register Time" and another "Name" that is the name of my Employees. Then I got a Formulary that is where I register my Employees "Monthly income" inputed in same ...
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9 views

Product Features table for No Sql Databse

I want to design database to save products features. Actually i want to store all features of mobile given on this link http://www.gsmarena.com/samsung_galaxy_j7-7185.php After search on google i ...
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1answer
34 views

DB Design - 1 column for each dataset OR dataset_name AND dataset_value?

I am creating a database table for storing numeric time-series data sets regarding cities that will be accessed via a web app. Primarily annual, quarterly and monthly data will be stored in it. ...
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1answer
112 views

ER Diagram - View Intergration/Centralised approach

Could anyone enlighten me on the difference between a view integration and centralised approach when designing a database, and how the ER diagram can be used to illustrate upon this; can't seem to ...
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1answer
141 views

Is my shopping list database schema good enough?

I'm wondering if my schema is correct? It's intended to hold shopping list items for each user, a user belongs to a household. Items will be added to the household. The stocklist will to hold the ...
2
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0answers
33 views

Looking for suggestions to model a database of Electrical Components

We have a database of electrical components and I am trying to make sure I have a good design. I am not a database designer (my comfort zone is designing with these hardware components), so I am ...
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15 views

Modeling a database with UML scheme and every type of relations

Good evening! This is my second database designing, the first one can be found here. I want to find the relational scheme of bridal registry database given in the following French UML graph: I ...
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2answers
108 views

Normalizing a table with a field that generally uniquely identifies a row, but is sometimes null

forgive me if this has been asked and answered before. I'm roughing out a schema for an inventory management system, to be implemented in PostgreSQL. All of our products and services have a sku. ...
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28 views

Normalized college database desgin

I try to create a college database College offer UG and PG courses in various departments. Department like MCA,MBA,Engineering Courses offered by MCA is lateral and regular , Courses offered by MBA ...
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0answers
29 views

what prerequisite are required to become a DBA?not overview but to the depth of course [duplicate]

what prerequisite are required to become a DBA?not overview but to the depth of course if any online link is there to learn or course to become DBA then let me know
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1answer
661 views

Multiple product attribute inventory database design

I have a database to build based on inventory for my shop. This is the current data that I have put into tables. This is the package: This is the product attribute: This is the table ...
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1answer
103 views

How to/Where to find MySQL templates for Toad Data Modeler

I have recently install Toad Data Modeler 5.3.4 and it only has Oracle data model templates. Where can I find and import the MySQL data templates so that I can create MySQL database models. I have ...
3
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2answers
54 views

Is it a good approach to duplicate data in a database?

I have a program that needs to store traceroutes (among other data). Here is a diagram that depicts the business scenario: My use case right now is to store the traceroutes using the following ...
3
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3answers
232 views

Normalising Customers and Employers with a people table

At what normalisation stage is it recommend to split say Customers and Employees into a People table and then link to the unique attributes of Customers and Employees? I can't seem to find the ...
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1answer
32 views

ON DELETE CASCADE doesn't work even storage table is InnoDb

I tear my hair with the ON DELETE CASCADE Clause. In fact I have two tables I'm on linux and I have installed lamp with phpmyadmin. That's the tables : CREATE TABLE a( Idatable bigint(20) ...
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0answers
14 views

SQLite text columns

When having a table in SQLite that has a TEXT data type, is there any implication if the length of the contained string differ significantly?
7
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1answer
497 views

CouchDB and document versioning

I'm currently working on a wiki-esque application using CouchDB and am trying to implement a document versioning scheme. The way I see it there are two ways of doing this: Store each version as a ...
0
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1answer
40 views

Do I have to use Foreign key as part of composite primary key or not?

I'm designing a relational database. This is what I'm trying to design: I will have production orders and products. A production order will have one product, but a product could be on zero or more ...
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2answers
445 views

Optimize large table design

First, I am a complete novice when it comes to databases, but have been given the task to speed up queries on a large set of data. (Hundreds of millions of records) The current implementation is a ...
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0answers
30 views

Want To Learn About MongoDB [closed]

I am doing a little bit of research on MongoDB related to the following key points: (i) Experiment And Results (In which applications, MongoDB is used and what are the results) (ii) Threat To ...
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0answers
42 views

Design a ER for hospital database system [closed]

I trying to design an ER Diagram for a hospital database, and the developer of the database determent what they want in the system of the hospital .. but some of what they want I cannot understand it ...
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0answers
11 views

use Case Diagram [closed]

There is an organization that provides residential facility to their staff and allot a colony for this purpose. There is also a school for girls and boys separate in it where the children of the ...
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0answers
14 views

For about ~50,000 - 100,000 records, how much RAM is required for analysing? [closed]

I'm working on A Python Data Analysis Project. The Database would contain about ~50,000 to ~100,000 records. How much Ram would I need perform the processing in how much time? i'm working on 64 bit ...
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0answers
23 views

problem with column oriented dbms features

I am currently looking for a free(or at least low cost) column oriented DBMS with really good compression abilities (at least 10:1 ratio) and fast response time. Having evaluated multiple open source ...
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0answers
11 views

Data Modelling of product and product variations

I want to model product and product variations using mongodb (mongoose) I am really confused with how shall I model both I need to add stock and price to variations. Variation can be of anything (not ...
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0answers
39 views

Ternary relationship with history tracking

I have the following entities Procedure -> id_procedure , desc_procedure . Status -> id_status , desc_status . Subprocess -> id_subprocess , desc_process . The rules are: 1 ...
1
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1answer
40 views

How to design a database for query builder project?

I have this project in which user can create queries using web based UI in which there will be list of columns and applicable operators. Later users can edit these queries, too. So I need to store ...
1
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1answer
43 views

Limit the number of records depends on the part of primary key

I created database for football matches. I have 2 tables with a many-to-many relationship, so I also created a junction table: Referee CREATE TABLE referee ( id_referee INT IDENTITY PRIMARY KEY, ...
3
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1answer
31 views

Store the content book in database, so that it would be updated afterwards or store them as document?

I have some books in (urdu) made with Urdu Inpage(tool for making pages in urdu) like this: problem that these document files are difficult to read in php because they gives unread-able characters, ...
0
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1answer
3k views

Storing multidimensional array in MongoDB

I am attempting to convert a large MySQL database of product information (dimensions, specifications, etc) to MongoDB for flexibility and to move away from the restriction of a column based table. I ...
10
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2answers
3k views

Ready-to-Use Database models example

Where can I find ready-to-use database models ? I don't need a database with data in it, but only schemas (UML diagrams). Perhaps something like the data models at this link, but much more complex ...