Relational Databases

This tutorial covers what many people agree is one of the most difficult database conceptshow to create and work with . A relational database contains two or more tables that are related to each other in some way.For example, a database might contain a Customers table and an Invoices table that contains the customer's orders.
In this tutorial you will learn how to link tables in an existing database together in a one-to-many relationship to create a relational database. You will also learn how to enforce referential integrity between those tables to keep records in related fields valid and accurate.

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Relational Databases and Database Applications
The first databases implemented during the 1960s and 1970s were based upon either flat data files or the hierarchical or networked data models. These methods of storing data were relatively inflexible due to their rigid structure and heavy reliance on applications programs to perform even the most routine processing.
In the late 1970s, the relational database model which originated in the academic research community became available in commercial implementations such as IBM DB2 and Oracle. The relational data model specifies data stored in relations that have some relationships among them (hence the name relational).


Understanding Data Relationships
Access is not restricted, however, in how you can organize your data. It also lets you set up relational databases. In this tutorial, you will learn what a relational database is and how to create one in Access.
By the time you finish this tutorial, you will understand the following key concepts: what a relational database is, how information in tables can be related, why keys are important in a relational environment, how to create a relationship between two tables and what referential integrity means.


MS-Access 2007 Table creation
Relational databases are constituted by one or more tables than contain the information in an organized form. Databases usually contain more than one table and each one will have a fixed number of fields.


Tips and Tutorials
Microsoft Access is a database management system (DBMS). It lets you create relational databases, which means that Access databases can link to tables that have similar fields. Access databases are the workhorses of many offices, often used for mailing lists, phone lists, and as address books. But there's a lot more to Access than that, as the articles in this section prove.


Help, Tutorials and Tips
Microsoft Access is a database management system (DBMS). It lets you create relational databases, which means that Access databases can link to tables that have similar fields. Access databases are the workhorses of many offices, often used for mailing lists, phone lists, and as address books. But there's a lot more to Access than that, as the articles in this section prove.


RDBMS Basics (Relational Database Management System)
Basically RDBMS (Relational Database Management System) is nothing but a standard. For many years database industry was not having any standard for storing and retrieving information. As a result of this standard we came up the language called SQL or Structured Query Language. We use SQL to communicate with RDBMS databases including but not limited to MS Access, Oracle, MS SQL Server etc. MS Access databases used to have file extension as .mdb but in 2007 release the default extension is .accdb.


Designing Good Relational Databases
Databases have a reputation for being difficult to construct and hard to maintain. The power of modern database software makes it possible to create a database with a few mouse-clicks. The databases created this way, however, are typically the databases that are hard to maintain and difficult to work with because they are designed poorly. Modern software makes it easy to construct a database, but doesn't help much with the design aspect of database creation.
Database design has nothing to do with using computers. It has everything to do with research and planning. The design process should be completely independent of software choices.


Learn Database SQL Technology
Structured Query Language (SQL) is a language that was developed by IBM for processing data in mainframe databases. The relational nature of databases and the ease of SQL usage has made SQL the standard language for databases. SQL technology is also standardized which makes it ideal for usage across multiple fields. Learning SQL database technology will enable you to program and maintain any database with ease.


A very basic relationship question
I am creating a BASIC (in relation to what thing you guys do on this website) relational database using access.

It is for a cleaning business so that they can organise bookings.

I think I need 4 tables:

* Clients
* Bookings
* Staff
* ServiceTypes

linking each of these to the bookings table using primary keys in the first field of each of the other tables will link them and allow me to do relational work (queries etc.) right?

Somebody told me that I need this though:

* Clients
* Bookings
* Staff
* ServiceTypes
* ServiceBookings (this contains the "ServiceTypeID", "BookingID" and "TotalCost" (The ServiceTypes table has hourly cost of each service).

I don't know why he suggested the second lot of tables instead,

I have only ever made flat-file databases, this is the first relational I have ever made so please don't be too technical


Free Access XP Tutorials
Microsoft Access is a powerful tool that you can use to create relational databases for storing and retrieving information. A relational database is an application that allows you to organize, manipulate, query and view your data, while building links between related topics. In the same way that a word processor helps you create a document, Access helps you create a database. A database is a collection of information relating to the same topic just like how a rolodex keeps a collection of names and addresses.


Table Design Examples & Recommendations
Table Design examples for all aspects of Access databases can be found in this area of our website. The goal of this table design tutorial is to provide information for beginning Microsoft Access programmers and future customers so that they will gain a basic understanding of relational databases.


Introduction to Databases and RDBMS
A database is a collection of files, a Database Management System (DBMS) is a program (set of programs) that stores and organizes data. One such organization method is relational where data is organized by means of related tables called relations and hence the name Relational Database Management System (RDBMS). RDBMS stores information in related relations (tables, subjects) which can be related using common fields.


Ways to get started if you've used other database or spreadsheet applications
If you are familiar with other database or spreadsheet applications, then you probably know the basics of how these applications work and what databases are used for. Microsoft Access differs from many other database applications by allowing you to create relational databases. Access also provides many options for working with other database programs such as Microsoft SQL Server.


Writing a mapped relational schema for foreign and primary key?
Below is a list of the relational schema: PATIENT: national ID, Clinic number, Namr, surname


IT Database - Relationships
I've been trying for a while now to create a relational database for IT management. Here's my plan:

- PC Table
-- Hardware Table
--- RAM Table: Size, Speed, Brand
--- GFX Table: Size, Speed, Brand
--- Storage Table: Type, Size, Speed, Brand
--- Peripherals: (mice/keyboard/usb ports etc.)
-- Software Table: Name, Version, Price

Basically I want to be able to generate forms etc. of say PC1 and know what software it has running, it's specs, etc. I haven't used relational databases since college so I'm a bit rusty.Here's a screenshot of what I've got so far, for some reason it doesn't seem right to me:

Or even if there is a template that fits my needs. I found a few but they had too much or too little of what I need.

If you wish to download the database: [LINK]


How to Merge Records from Two Identical Access Databases
The process of merging relational data can get quite complicated, especially when you have numerous core-data tables as well as lookup tables. Danny Lesandrini explains the basic steps.


MS Access 2007 Step by Step
Basically RDBMS (Relational Database Management System) is nothing but a standard. For many years database industry was not having any standard for storing and retrieving information. As a result of this standard we came up the language called SQL or Structured Query Language. We use SQL to communicate with RDBMS databases including but not limited to MS Access, Oracle, MS SQL Server etc. MS Access databases used to have file extension as .mdb but in 2007 release the default extension is .accdb.


Advice for New Database
I'm looking to build a custom database for a small health and medical supply business. The database should be allow us to manage inventory, maintain customer records, and execute cash register transactions.

A primary goal of the software is to be able to use a scanner so that inventory can be more easily managed. It will be managed on a single computer (right now).

I am familiar with MS Access and have made relational databases using the application; however, I have never integrated the databases with a barcode scanning system or a cash register.

1. Do you know of any information as to how to setup MS Access to work with scanners or register? For those of you that have done this, is this a difficult setup process?

2. As the business grows, what are some other data management approaches would you recommend?


Query several databases to UPDATE one
I have 14 databases, each with tables that have identical fields. All the tables have a unique employed identification number acting as the primary key, there will be no duplicate keyfound between any of the databases.

It was necessary to have separate databases so that workers on the same LAN could update their own particular databases at one time.

I want to bring all this data together into one database so I can extract meaningful data about the project as a whole. I've been trying to figure out how to do this for several days, and I'


HELP, Query from two different databases
I have two databases. I need to create a query in one of the databases. But, there are some data I need in the second database. I really want to know how I can connect/join two differenttables in two different databases.

And say the two tables are large so that importing one table to an other database is not possible.