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

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5
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2answers
83 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. ...
0
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0answers
22 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 ...
-4
votes
0answers
28 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
0
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0answers
14 views

Does use of remote servers increase overhead?

In considering the use of remote databases/servers, to what extent does their use increase overhead in terms of time as well as CPU usage and communication costs? Is there documentation on this issue? ...
1
vote
1answer
660 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
101 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 ...
0
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0answers
18 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 ...
2
votes
0answers
30 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 ...
0
votes
1answer
19 views

How to use pivot when there are three fields and u want to put them in one category

I have data in this format Skill Min Ideal Max ========================== C++ 0 1 1 I want to display it like this Criteria C++ ================= Min ...
3
votes
2answers
53 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
231 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 ...
0
votes
0answers
9 views

Modeling a database with UML scheme and evey 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 ...
1
vote
1answer
26 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) ...
0
votes
0answers
11 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
494 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
38 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
vote
0answers
25 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 ...
1
vote
2answers
442 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
votes
0answers
27 views

Want To Learn About MongoDB [on hold]

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
votes
0answers
40 views

Design a ER for hospital database system [on hold]

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 ...
0
votes
0answers
11 views

use Case Diagram [on hold]

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 ...
0
votes
0answers
14 views

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

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 ...
0
votes
1answer
44 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
votes
0answers
19 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 ...
0
votes
0answers
14 views

Physical Model Design to Conceptual Model Design

Is there software that allows you to create a physical model design and convert it to a conceptual model design?
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0answers
16 views

Database design with conditional tables

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 ...
0
votes
0answers
10 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 ...
1
vote
0answers
38 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
vote
1answer
38 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
vote
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
votes
1answer
30 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
votes
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
votes
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 ...
0
votes
1answer
30 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. ...
3
votes
1answer
24 views

How to represent the optionality of a many-to-one mandatory relationship from the Parent to its two Child entity types in an ERD?

I have a Parent entity type with two Child entities, with a relationship cardinality of many-to-one (or M:1) from Parent to Child. The business rules say that: It is mandatory that the Parent ...
1
vote
0answers
12 views

Time series data and utc conversion

I'm storing data in minute, hour, day, month and year buckets. All data is stored in UTC. Let's assume a client is in PDT time (-07:00 UTC) If the client wants to query for the hour sum of 4/23/2016 ...
1
vote
1answer
49 views

Database design for ordering complex products

I'm working on a platform in which you can order food from different sellers. Currently the platform is working and restaurants can create food products while clients can order them. Easy enough. A ...
1
vote
0answers
21 views

Varchar PrimaryKey. Clustered or nonclustered? [duplicate]

I am working on a legacy database. The primary key is clustered varchar(128) and the table contains a high volume of data. Does it necessarily help performance if I change the clustered PK to ...
2
votes
0answers
42 views

Clustered index on a fact table

I'm trying to work out what field(s) to use for the clustered index of my fact tables (which all have a similar structure). I'll use FactSales as an example: CREATE TABLE dbo.FactSales ( ...
0
votes
1answer
59 views

FK Issue with Fact Table

I have a Datawarehouse star schema. One Dim table is 'DimTweet'. This contains tweet details. For a selected date I want to be able to display the number of tweets. However, I have a problem in my ...
0
votes
1answer
108 views

Zerofill Auto Increment - mySql

Ok, So I'm working on an app and I can't remember, for the life of me, why I set a zerofill on an Auto_Increment column when I created the database. And I couldn't exactly find any compelling info ...
2
votes
1answer
1k views

Party Data Model / Universal Data Model Example

I am trying to implement Party Data Model / Universal Data Model in our application which needs to store different relationships between entities (People, Companies). Example of relationships: ...
0
votes
1answer
26 views

Storing mail in database, data type

I've found pretty poor informations about mail databases. My need is to archive mail messages downloaded from a normal pop3 or imap account: I am an ordinary user and I do not own the server, but ...
1
vote
3answers
266 views

Working NoSQL scheme for a betting app

I'm building an app where a user can bet on the result of a sports game. Basically, we feed the database with competitions and games, and the users can place their bet in the form of a score ...
0
votes
1answer
102 views

What Is the Next Best Ingredient to Add?

I am building a program that allows users to optimize their grocery shopping so they can make the most recipes using the fewest ingredients. One of the features of this program is a function I’m ...
0
votes
1answer
232 views

How does Snapchat store its data?

I am a highschool student who is interested in developing apps and learning more about databases and servers, so please bear with me if this is the wrong place to ask or if it's a obvious answer. I ...
0
votes
0answers
21 views

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 ...
2
votes
1answer
21 views

Count of range on datetime in MySql

I want to group table entries for each userId only if they are consecutive entries in the table. I have a table like this. id userId transactionTime 1 1 2016-04-13 22:15:44 2 1 ...
2
votes
1answer
20 views

Multiple columns from one table rely on one single table

I'm working with PostgreSQL 9.2 and have the following relation between 2 tables: The table town stores a list of town codes. The table perimeter stores perimeters denomination. Towns are almost ...
0
votes
1answer
24 views

Design question

I want to implement an extension to my following table Object table == building in generall +--------+-----------+------+--------------+-----------+-------+------+ | obj_id | obj_ident | name | ...