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

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0
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2answers
47 views

Should every table in my database include store id?

I am designing single database for multiple stores. Every store may have different products and stock. should i have to include store_id in every table in database. my database looks like this
1
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2answers
31 views

Best practice for multiple 0,1 to many relationships

I'm an application developer without a ton of database design experience and I'm wondering if someone can suggest a design/implementation for relating one table to one or more other tables. For ...
16
votes
8answers
3k views

Why would a primary key value change?

I have been researching the concept of ROWGUID's recently and came across this question. This answer gave insight, but has led me down a different rabbit hole with the mention of changing the primary ...
1
vote
0answers
33 views

Storing Business Logic in Tables rather than Stored Procedure or Application

The requirement is that once the product has been delivered, user can update the logic as he wants. An example of logic I have is follows- An institute teaches English has following requirements - ...
15
votes
3answers
551 views

Implementing subtype of a subtype in type/subtype design pattern with mutually exclusive subclasses

Introduction In order for this question to be useful for future readers I will use the generic data model to illustrate the problem I face. Our data model consists of 3 entities, which shall be ...
1
vote
1answer
20 views

Changing Key (PK, FK) properties in DROP/Add column statements

I want to change a table by adding a column. So far nothing to see here, BUT I would like to make this column part of a composite key, i.e., I now have a layout table_name( Field_1 datatype PK, ...
11
votes
1answer
188 views

Modeling a database for Video Game related information with multiple many-to-many relationships

Scenario I am relatively new to database design, and I decided to make my own hypothetical database for practice. However I am having trouble modeling and normalizing it, as I esteem that there are ...
1
vote
0answers
60 views

database creation [closed]

I'm just starting using data bases and I want to create a table which will store some values and 2 other tables in it. If I were using java for instance I would create an array list of table document ...
8
votes
1answer
371 views

Best way to store a value which could be multiple types

I'd like to re-ask a question in a more direct and general way: How do you create a table to store values which could be multiple different types? In my case, the values provide diagnostics about an ...
1
vote
0answers
23 views

What frontend program is best for my specified needs? [closed]

I am currently an Electrical engineer and I have been tasked to set up a database(outside my realm of expertise) that will be used by multiple users over a networked drive. There will only be a ...
3
votes
1answer
71 views

Best practices, MySQL table with 150+ columns, many null

I have a table storing property data for thousands of properties, all coming from a feed. (updating at least once a day). I'm certainly not an expert with databases and would appreciate some guidance ...
1
vote
1answer
49 views

Distinguish between unknown and non-present foreign keys

I'm in the situation of importing data from multiple other applications. The data is stored in multiple tables that contain foreign keys. Some of these applications don't provide all the needed data ...
1
vote
0answers
35 views

What is the difference between (Superclass/Subclass) Total and Partial Specialization?

What is the difference between total and partial specialization of superclass/subclass (or supertype-subtype) structures in enhanced entity-relationship modeling?
0
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0answers
55 views

Get rank of users based on dynamic points

I have this db structure for my ranking system. users table id username 1 alex 2 john points table id name description value 1 foo bar 100 2 bar foo ...
0
votes
1answer
33 views

Data Relationship between Provinces and Cities

Does anybody have experience or know how to correctly design database relationships for where Provinces ->hasmany cities City ->hasOne Province the problem is different cities (based on geography /...
0
votes
0answers
35 views

Design schema for booking appointment/time slots

I'm trying to figure out the best way to design the database. I already have a Client table which consists of id, name and email. A client can book many dates for appointment and each date has only 3 ...
1
vote
1answer
23 views

Insert column name as value

Consider the following, in PostgreSQL: drop table test ; create table test (result1 text, red smallint, green smallint, blue smallint, results2 text) ; insert into test values ('red',1,2,3) ; I ...
0
votes
1answer
40 views

can i have password for my mysql table

is there a way i can set password on a table i am creating in mysql. i am working with rather sensitive data , and i have to use mysql on a server on which i am obviously not the admin. so people ...
2
votes
1answer
65 views

Placing a uniqueness constraint on a date range

I have a table reservation with columns roomno(INTEGER), startdate(DATE), enddate(DATE) with a primary key on (roomno, startdate). How do I place a constraint on the table such that bookings are not ...
5
votes
2answers
80 views

Using schema + Filegroups or entirely separate database(same instance) to partition some big tables?

I have the following challange: I have a staging database which holds a few big tables (on SSD) but I start to run out of space on the SSDs. I use SQL server 2014 BI-Edition (= Standard Edition for ...
1
vote
0answers
18 views

Database Designs Alternative to Polymorphism in Establishing Relationships

I'm working on a database which handles replacement of parts in a machine. Rules A machine has many components A machine has a set of assembly instructions Many components have many part (screws, ...
0
votes
0answers
26 views

Tag system for multiple Item types and groups Schema

I have a groups table and users table, and a many to many relationship between them. In my app, there are different modules, like question, product,suggestion , etc. Users can create products/...
1
vote
0answers
26 views

pub/sub database schema

I am having a hard time creating a pub/sub database schema with stateful metrics. Saying it aloud it sounds easy enough: "There are many organizations that will subscribe to checklists that are ...
0
votes
0answers
45 views

MySQL - Database Design : Encrypting user id and creating a mask for further internal references

For a food order delivery system that I am working on, I want to make sure my user's private information is well protected; from system admins too. So I thought of coming up with this concept of ...
0
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0answers
35 views

Mongo Schema for large time series data sets

I'm not a DBA but a C# developer, my experience so far is with MS SQL, so please keep that in mind. I am trying to design a scheme to store sensor data and have it organized. Each TestRecord would ...
2
votes
1answer
29 views

Optional Parent-Child relationship

I have a problem modeling a relationship whereby the child may or may not be related to a parent. For example. You have a Band database with a Tour(parent) table, and a Gig/Concert(child) table. Now, ...
2
votes
2answers
63 views

How can I represent a list of words and related words in a relational structure?

I have a list of header words and words as below and I am trying to understand how best to represent these in a relational table: Header Other Words Words abandon abandoned, ...
2
votes
0answers
28 views

Could I use both UUID and Sequential ID or is it bad design

Sequential IDs have pros and cons. UUIDs have pros and cons too. Why not use both for each table? (Let's say I have -and will have- no problem about storage space) I could use: UUID for exposition, ...
0
votes
1answer
75 views

Products with different prices in an order

I have a "classic" database schema for order and products: Orders ------ id etc. Products -------- id name etc. Order Products --> Pivot table -------------- id --> some people don't like ...
2
votes
1answer
38 views

Conditional relationships? One-to-many relationship using a pivot table for only a type of entity

I have the following tables: users: - id - name - user_type_id (references id on user_types) neighborhoods: - id - name homes: - id - house_number - neighborhood_id (references id ...
0
votes
1answer
24 views

Checking for BCNF in a relational database through FDs?

Okay so I know that for BCNF, when listing all non-trivial FD's that everything to the left has to be a candidate key. So I have this relation: Person(Id, TFN, Name, Phone) Where Id and TFN(Like ...
1
vote
3answers
127 views

Avoid repeated traversing of hierarchical data when parsing a big tree frequently

I have a hierarchical/tree data structure in Oracle/RDBMS where I need to traverse the tree frequently. The tree is huge and therefore parsing it every time will not be efficient. A better way could ...
1
vote
2answers
41 views

Dynamic script to Drop Indices of a specific column

I´m currently writing an SQL script to update our database and for that I need a script to drop indices that rely on a specific column (because I also want to drop the column). In my script I have ...
0
votes
1answer
51 views

Raise Multiple Exceptions Postgres

I am using Postgres 9.5, and I am trying to create exception handling in a stored procedure/function. I can't quite figure out how to raise the error should any of the 'INSERT' statements fail. If ...
3
votes
1answer
74 views

Basic question: Simplest way to share company databases

My company is looking to access large quantities of data from another company we have good relations with. Currently we are using a web interface to interrogate their information, however it is quite ...
9
votes
1answer
241 views

Overcoming the SQL Server Express Edition limitation

Microsoft SQL Server 2014 Express edition has a database size limit to 10GB. Now, is that just for a single instance or the overall size that the edition will allow? Or does that means that I can have ...
0
votes
0answers
33 views

DB design: Store data VS more complex DB changes

This is my current DB structure. -- -- Table structure for table `prods` -- CREATE TABLE `prods` ( `prod_id` int(11) NOT NULL, `prod_name` varchar(255) NOT NULL, `prod_aaa_id` varchar(255) ...
3
votes
0answers
61 views

Personal Finance database review

G'Day, I found that someone had started on this topic on personal finance, I like to go further using a good personal finance plan I found on the internet which I would model. In advance please ...
6
votes
1answer
86 views

Is my implementation of type/subtype design pattern (for mutually exclusive subclasses) correct?

Introduction In order for this question to be useful for future readers I will use the generic data model to illustrate the problems I face. Our data model consists of two entities, which shall be ...
0
votes
0answers
61 views

Using the same tables for multiple many to many relationships

I currently have a project where I need multiple Many to Many relationships some of them are roughly and I started to wonder if using an extra column on the table to specify the table it's related to (...
4
votes
3answers
221 views

Maintaining integrity between 3 tables when reference could be through or direct

Say we have the following 3 tables: tUsers (ID, name, countryID, regionID) ------ 1 | Joe | 1 | 1 2 | Sue | NULL | 2 3 | Bob | 2 | NULL 4 | Amy | NULL | NULL tCountries (ID, ...
0
votes
1answer
31 views

PostgreSQL values to unique dictionary

I have table with one billion rows and more than 50 columns. I need to reduce size and speed up queries, backup, exports, etc. Some columns contain f.e. only hundreds of distinct values which are long ...
1
vote
2answers
36 views

Scalable way to track who's viewed a post? [closed]

I'm building an app that needs to check who, out of millions of users, has not received a post. If a post hasn't been seen by many people, this task will be easy. But if a post has been seen by nearly ...
0
votes
3answers
108 views

Best name for link table [closed]

I was wondering what the best name for a linked table in this situation (or any) would be. I've searched for this, but could not find any concrete examples. For example, I have the following tables (...
1
vote
1answer
64 views

Composite Primary keys and auto increment?

i'm developing SaaS app with multi-tenancy, and i've decide to use single DB (MySQL Innodb for now) for client's data. I chose to use composite primary keys like PK(client_id, id). I have 2 ways here,...
-3
votes
1answer
30 views

Database engine disk access [closed]

Do you know what is the difference between the database engine get rows in a table without and with use of an index in a disk prespective. They way the engine access the table in disk is the same when ...
0
votes
0answers
37 views

Should I break up this MySQL table?

Existing table (more or less). It has about 1 million rows: id article title stage 1 zipfile name stage 1 delivery date stage 1 checked date stage 2 zipfile name stage 2 delivery date stage 2 checked ...
1
vote
2answers
104 views

Need advice on database normalization

I am working on a basic blood bank database on Oracle. I would like to create a completely basic normalized table and then I will add more details to it. I have done it to the 2NF and I will further ...
1
vote
1answer
36 views

Database design for surveys and experiments

I have only a bit of experience in working with databases, but rather theoretically during my studies and not so much practically. I was wondering if someone could help me figuring out how to design a ...
10
votes
5answers
1k views

How to hide/disable tables without dropping them to check redundancy?

I have to maintain and extend an old legacy system which contains webservice methods and database tables that are no longer used. Since I’m not entirely sure that the tables are really redundant, I’m ...