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

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1answer
29 views

Data transferring

Is there any practices to transfer data from two databases that have different structure of table ? For example : old system : table [folder] with col: FolderId, name, age, sexe, date, orders New ...
6
votes
2answers
123 views

Creating relationships between tables that where not specified in the given UML diagram

Good evening! I'm working on designing my very first actual database from the following UML class diagram (in French unfortunately): I'm at the point of creating the relational sketch of it which ...
1
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2answers
21 views

Postgres Update Limit

I'm curious if Postgres has anything in place where I could limit the amount of rows kept for a ID. For example, say I have a users table and login_coordinates table. Every time the user logs in, ...
0
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0answers
26 views

Which NoSQL Database is best suited?

I have been reading a lot of blogs trying to determine which NoSQL database would be best. I am looking at moving from file based (xml) storage to using a database. The application will be storing ...
0
votes
0answers
13 views

Mongodb database design

I'm planning to implement this schema in Mongodb, I have been doing some readings about schema design, and the notion was whenever you structure your data like a relational database you must be doing ...
0
votes
0answers
37 views

Normalized college database desgin

I am trying to create a college course database. The College offers UG and PG courses in various departments. Departments include program streams like MCA, MBA, and Engineering. MCA courses may be ...
0
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1answer
26 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 ...
6
votes
2answers
244 views

Table Relationship - One to Few (Many)

I know the title may seem confusing but I have yet to find a solid answer to this design pattern. Let's say I want to create an Employee table and have multiple addresses for each employee. So this ...
0
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2answers
7k views

MySQL count multiple columns and sum the total occurrence

I have the following table, say, MyDRAW ... DRAWNO PRIZENO FIRSTD SECONDD THIRDD FOURTHD M123/14 8458 8 4 5 8 M123/14 7214 7 2 1 4 M123/14 1640 1 6 4 0 ...
2
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0answers
36 views

When do you know that you've made a design flaw in a SQL/relational database?

I've been working with a a relational model for a work project over the last few months, and I've gotten to the point where I'm wondering if I've made a mistake in my model's design or implemented ...
-6
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0answers
17 views

Components of Time Variant Data [on hold]

Specify components that would be required to hold time variant data for policy enforcement and training management
2
votes
0answers
38 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 ...
0
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1answer
576 views

How to organize the tables of a MySQL database with several statistics data of several years?

I am developing an app that must provide statistics information about the distribution of the money that a person spends each year in taxes in the city where he lives. The user should select the ...
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1answer
42 views
+50

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 ...
0
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0answers
10 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 ...
1
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1answer
57 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: ...
0
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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 ...
0
votes
1answer
39 views

Altering column data SQL [on hold]

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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votes
0answers
13 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
votes
1answer
67 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
votes
1answer
64 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 ...
0
votes
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 ...
1
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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
votes
1answer
44 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 ...
-1
votes
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?
1
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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 ...
0
votes
2answers
782 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
votes
1answer
184 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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votes
1answer
28 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 ...
0
votes
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 ...
0
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0answers
13 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 ...
0
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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 ...
0
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0answers
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 ...
0
votes
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. ...
1
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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 ...
1
vote
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 ...
0
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0answers
16 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 ...
7
votes
2answers
114 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. ...
-4
votes
0answers
30 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
1
vote
1answer
664 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 ...
0
votes
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
votes
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
votes
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 ...
1
vote
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
16 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
votes
1answer
502 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
votes
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 ...
1
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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 ...
0
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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 ...
0
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0answers
44 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 ...