A schema of a database system is its structure described in a formal language supported by the database management system (DBMS) and refers to the organization of data to create a blueprint of how a database will be constructed (divided into database tables).

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Handling Strong and Weak entity types in a one-to-one relationship

I am modelling a database for a term project and I have come across something I do not have a definite answer to. Diagram I was supplied with the following Entity-Relationship diagram: ...
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474 views

Should we create a schema per “project”?

This is a database where users create a 'project' and work on it. We have a table for project and various other tables that contain different attributes for project (multiple rows for each project ...
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33 views

Array or Object?

I am using MongoDB and designing a database. There is a list of itemCode. It won't change, but some new one will be added at some point. The total number of itemCode will never be over 100. Each ...
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489 views

Schema design for products with multiple variants/attributes?

I'm using MySQL. The idea is similar to shopify with a different concept, so users are going to add their own products with multiple types of variants and attributes. From all the research I've done ...
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61 views

Does exist some software for transforming data from one DB schema to another?

I need to transform between two different database schemas the same data. For example i have one table in old schema like this: and i need to transform it to new schema like this: So i have few ...
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56 views

What is the name of the default schema in Oracle?

When you create an object in Oracle, and do not specify a schema (object prefix), is there a name for that default schema? I see in Oracle SQL Developer, that a newly created object shows up in the ...
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Copy complete structure of a table

Using some methods, when you create a copy of a table you lose indexes, PK, FK, etc. For example in SQL Server I can say: select * into dbo.table2 from dbo.table1; This is just a simple copy of the ...
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25 views

Database schema for timesheet app?

I am very new to database managements as I am enrolled in my first class involving databases at university. For my project, I have to create an app that clocks employees in an out and keeps track of ...
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17 views

Category of the same object in SQL and Inheritance.

I am trying to make the relational schema for a shop which sells ice creams and drinks. As the ice creams and drink both fall in the same category of Items, i tried making the items entity but i am ...
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22 views

Table design one or more

I am struggeling with the following issue. I have a table executives and supervisor, quite similar in the structure. Both of the executives can have a Car one or more. Should I make a table ...
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88 views

Best design to reference multiple tables from single column?

Proposed schema First and foremost, here is an example of my proposed schema to reference throughout my post: Clothes ---------- ClothesID (PK) INT NOT NULL Name VARCHAR(50) NOT NULL Color VARCHAR(...
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220 views

Efficient Database schema for multi-lingual content?

Assume I have a table for blog posts, posts, and schema as id author title content and each post can belonged to some categories id name descrtiption So a blog post can belong to multiple ...
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13 views

Database ERD for orders info

I have two tables: 1-orders order_id 2-shipping_and_billing order_id FK address_type(billing and shipping ) city I need to get full info of shipping and billing in single select of ...
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66 views

Database design in MySQL workbench

After doing some change As Mr Vérace told me here in this question, by changing the id names of each table into table_name_id and using the singular notation, I still need your opinion about this ...
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39 views

Manual postgres migration for Django (python) app

I have a Django (python) data model called Message: class Message(models.Model): text = models.CharField(max_length=50) sending_time = models.DateTimeField(auto_now_add=True) I added sender ...
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1answer
150 views

Database design for dentists

I have a homework, where I should create a database for a dental clinic using MySQL Workbench. This database will be used later for a web app for dentists. Here is a picture of the database design: ...
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1answer
999 views

Installing OE (Order Entry) schema in Oracle Express

I'd like to know if it's possible to install OE (Order Entry) schema in Oracle Express. If so, how can I do that?
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1answer
171 views

Design for scientific data. Data table with hundreds of columns or data table with a generic value column and hundreds of rows (EAV)?

I am trying to improve the data storage in biomedical science lab where I recently started working. The existing workflow is atrocious, involving many differently formatted Excel sheets that all get ...
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3answers
78 views

Help with database schema design

I'm working on an Android application which utilizes a number of MySQL databases. The design is as such: Users have many recipes. Recipes have many ingredients Recipes have many directions I ...
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11 views

Restrict postgresql roles based on rows in upper level table

We have a postgresql database, and it is expanding to be used by more groups. The data from these groups will all live together in the same tables, but we need to restrict access to the data based on ...
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1answer
33 views

Login Schema Role User Setup

Environment: Windows Server 2012 SQL Server 2014 Standard Public website (Site-A) on Server Private website (Site-B) on Server Windows App running on workstations SQL Server 2014 Standard: 2 ...
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1answer
230 views

ERD for a web development company

I am working on an ERD which represents the relationships between entities in a Web development company behavioral model. There I have entities like: Customer Service ----------- (like: web ...
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1answer
44 views

Explaining the problem with a column of values from a non-mutually exclusive domain

I'm trying to convince the powers-that-be that their current database design is risky and inefficient. I'd like to verify whether my assumptions are correct, and I'd like help in finding technical ...
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2answers
1k views

Database design of Room Booking system in a Hotel

Intro and System Description I am currently designing a Database for a Room Booking system in a Hotel. Client fills a Form / Request with following information about Room: amount of people in ...
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Why default db privilleges are not applied on a new schema?

I have a user with all privileges granted by default in database properties. I create a new schema as postgres and table there. I expect that the user should have an access to this table but it looks ...
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81 views

create table in a different schema

I am trying to create a table on a different schema without using "create any table" privilege. I have an application user/schema. TABLESPACE_NAME USEDMB MAXMB ----------------...
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1answer
29 views

Every “INSERT” query check a combination of column's records

Unfortunately, my mind has stacked right now and i would like to design a really simple DB schema. What i want? In a simple table, for instance Table1, there are two different columns, Series and ...
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Schema Design for multiple many-to-one relationships. of which exactly one should exist

Say I have table A, B, and C. B and C can both be related to multiple A's, but each A should have exactly one of either B or C related to it. Which database design is better: A: a_id, b_id NULL, ...
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1answer
66 views

How can I create a MongoDB based on MySQL schema?

How can I create a MongoDB based on MySQL schema? This is my schema: productCode VARCHAR(15) productName VARCHAR(70) productLine VARCHAR(50) productScale VARCHAR(10) productVendor VARCHAR(50) ...
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1answer
40 views

Normalizing a folder schema

I've created a schema to allow creation of folders for customers. Customers Id Firstname Lastname StreetLine1 StreetLine2 City CustomerFolders Id CustomerId ParentId (NULL) Name Now as you can ...
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1answer
55 views

Database design for actions on some entity

I am making a todo list kind of a service. One todo list will have several items , that can be done/deleted/snoozed etc. Users can also add a new item to the list , delete an item etc. I want to ...
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1answer
62 views

What are some databases that are schema-full but not relational

What are some databases/datastores that are schema-full, but not relational? In other word I'm after some NoSql databases that are not schema-less. By schema-full I mean that, like in a traditional ...
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4answers
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Open source tools for Oracle schema compares [closed]

I'm looking for an open source tool to generate DDL scripts. Many tools call these synchronization scripts. We essentially want to compare schema of different environments (ie: DEV to QA, QA to PROD)...
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4answers
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How do I list all schemas in PostgreSQL?

When using PostgreSQL v9.1, how do I list all of the schemas using SQL? I was expecting something along the lines of: SELECT something FROM pg_blah;
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1answer
76 views

How unique are MongoDB _id fields?

I am trying to create a schema for documents and collections for a MongoDB database I am creating. I have read a few documents describing the _id field that is generated by each document upon creation....
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How can I integrate a new system to a design scheme I previously created?

This is a follow-up to a question I wrote a while ago, for reference, you can look it up here. I've developed a curriculum based database scheme that looks like this(Thanks Joel Brown) Now that a ...
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2answers
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Import Oracle schema data without losing modifications of stored procedures

I have this scenario: One huge (thousands of tables), complex, Oracle 8 production database, One huge (thousands of tables), complex, Oracle 9 development database, (same structure as production) ...
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4answers
13k views

Query to compare the structure of two tables in MySQL

To automate the backup process of one of my MySQL databases, I would like to compare the structure of two tables (current version vs old version). Can you think of a query that can compare two tables?...
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2answers
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Decision criteria on when to use a non-dbo schema vs a new Database

I'm mostly an application developer but find myself having to do all the up-front database work for my current project (btw... its MS SQL Server 2008). As a first decision, I'm trying to figure out ...
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2answers
694 views

Searching 500 million records of binary data

I will inserting into a database the signatures of 500,000,000 pictures. The signatures will be generated using libpuzzle. Each signature is 338 bytes. (so 160 GB) plus a table for searching (read ...
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1answer
206 views

Trigger on a Schema

Is it possible to create a Trigger on a Schema? I have to audit the changes on my tables. But I have a lot of tables and I don't one to create a trigger on them one by one. --Database level trigger. ...
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14k views

Allow user to do anything within his own schema but not create or drop the schema itself

I have created a schema in SQL Azure and granted the following permissions to a database role: CREATE ROLE myrole AUTHORIZATION dbo; EXEC sp_addrolemember 'myrole', 'myuser'; CREATE SCHEMA myschema ...
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1answer
10k views

Best practices for schema changes and data migrations to a live database without downtime?

How do you make schema changes to a live database without downtime? For instance, lets say I have a PostgreSQL database with a table including various user data like email addresses etc, all ...
4
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1answer
285 views

Relation between multiple hierarchical taxonomies linked to a single entity

I am working on an online test application which supports multiple choice questions. I have created schema for taxonomy (classification) system to be used with questions. taxonomy(id, name, slug, ...
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2answers
1k views

Is it possible to get schema ID in another database without using dynamic sql?

I start with an object ID and a database ID. Inside a user defined function, I want to get the full name and ID of the database, schema, and object. How can I get the schema ID without using dynamic ...
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2answers
340 views

Database Schema for Blank Database is large. 20MB

Is it normal for blank databases with just schema to be large? Or is there a way that I can reduce the size of the initial database?
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1answer
13k views

SQL Server: grant select access to a user in a view and not in its tables

I have a SQL Server 2012 instance with a few databases. In one of them I created a view, that selects tables in more than a database. I want a user to be able to select that view, but it must not ...
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1answer
77 views

Permission in schema for user

I created a default database and created some schemas within this database. Created users for each schema, now I want to give full permission for each user in your schema only, how should I do?
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1answer
665 views

ER vs database schema diagrams

when i search the web for er diagram and database schema these 3 diagram types found but all are named under er diagram.i want to know what is database schema diagram and what is er diagram why all ...
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1answer
130 views

Read-only user query in Oracle

I have been asked to create a read only user in a Oracle database 12c. The read only user must have read only grants only to the objects of select schemas, which I created and handed over. But now ...