A question asked about data contained in two or more tables in a relational database. The relational query must specify the tables required and what the condition is that links them; for example, matching account numbers. Relational queries are tricky to specify because even the simplest of questions may require data from two or more tables. Both the knowledge of the query language and the database structure is necessary. Even with graphical interfaces that let you drag a line from one field to another, you still need to know how the tables were designed to be related.
An Early Relational Query
In the mid-1980s, Paradox was the first DBMS on a PC that made linking tables easier. Although not as sophisticated as today's methods, the ability to associate relationships by typing sample words was a breakthrough. The Customer No. and Part No. fields are related by "ABC" and "XYZ." Any words would suffice as long as they are the same.
An Early Relational Query
In the mid-1980s, Paradox was the first DBMS on a PC that made linking tables easier. Although not as sophisticated as today's methods, the ability to associate relationships by typing sample words was a breakthrough. The Customer No. and Part No. fields are related by "ABC" and "XYZ." Any words would suffice as long as they are the same.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
Additional Resources
- RazorSQL 5.0.2 (Mac)
- Query, edit, browse, and manage all major databases from one database tool. RazorSQL OSX is a universal database query tool, programming and sql editor, database navigator, and administration tool with built-in connection capabilities for DB2, Derby, Firebird, FrontBase, HSQLDB, Informix, Microsoft SQL Server, MySQL, OpenBase, Oracle, PostgreSQL, SQL Anywhere, SQLite,...
- Software downloads 2009-11-18
- Altova XMLSpy Professional Edition 2010 (Windows)
- Altova XMLSpy 2010 Professional Edition is the industry-leading XML editor and XML development environment, with intuitive editing views and powerful XML utilities to model, edit, transform, and debug XML-related technologies quickly and easily. In addition to the world's most popular XML editor, XMLSpy Professional includes a graphical XML Schema editor...
- Software downloads 2009-11-16
- Altova XMLSpy Enterprise Edition 2010 (Windows)
- Altova XMLSpy 2010 Enterprise Edition is the industry's best-selling XML editor and XML development environment for modeling, editing, transforming, and debugging XML technologies. In addition to the world's leading XML editor, XMLSpy includes a powerful graphical XML Schema editor that allows you to design complex schemas with ease. Advanced error...
- Software downloads 2009-11-16
- JumpBox for the PostgreSQL Relational Database Management System 1.1.5 (Mac)
- PostgreSQL is a powerful, open source object-relational database system that's been under active development for over 15 years. An enterprise class database, PostgreSQL boasts sophisticated features such as Multi-Version Concurrency Control MVCC, point in time recovery, tablespaces, asynchronous replication, nested transactions savepoints, online/hot backups, a sophisticated query planner/optimizer, and write...
- Software downloads 2009-10-29
- JumpBox for the PostgreSQL Relational Database Management System 1.1.5 (Windows)
- PostgreSQL is a powerful, open source object-relational database system that's been under active development for over 15 years. An enterprise class database, PostgreSQL boasts sophisticated features such as Multi-Version Concurrency Control MVCC, point in time recovery, tablespaces, asynchronous replication, nested transactions savepoints, online/hot backups, a sophisticated query planner/optimizer, and write...
- Software downloads 2009-10-29
- Amazon launches relational database service: Think MySQL in the cloud
- Amazon on Tuesday launched a public beta of a service dubbed the Amazon Relational Database Service RDS. The main appeal: Allow customers to operate and scale database clusters while leaving pesky tasks like patching and administration to Amazon Web Services. Adam Selipsky, vice president of Amazon Web...
- Blog posts 2009-10-27
- Aqua Data Studio 8.0.2 (Mac)
- Aqua Data Studio is a database developer's complete Integrated Development Environment IDE. The IDE provides three major areas of functionality: A) Database query and administration tool, B) a Suite of compare tools for databases, source control and filesystems and C) a complete and integrated source control client for Subversion SVN...
- Software downloads 2009-10-23
- QueryCell 1.3 (Windows)
- QueryCell is a plug-in for Microsoft Excel that allows you to query excel data using SQL within the Excel application itself. Save time by using SQL to Join regions of data. Use Group By, Min, Max and Avg on Excel Data. Generate test data easily. SQL Insert Statements for Excel...
- Software downloads 2009-09-01
- Aqua Data Studio 7.5.31 (Mac)
- Aqua Data Studio is a database developer's complete Integrated Development Environment IDE. The IDE provides three major areas of functionality: A) Database query and administration tool, B) a Suite of compare tools for databases, source control and filesystems and C) a complete and integrated source control client for Subversion SVN...
- Software downloads 2009-08-10
- RazorSQL 4.5.14 (Mac)
- Query, edit, browse, and manage all major databases from one database tool. RazorSQL OSX is a universal database query tool, programming and sql editor, database navigator, and administration tool with built-in connection capabilities for DB2, Derby, Firebird, FrontBase, HSQLDB, Informix, Microsoft SQL Server, MySQL, OpenBase, Oracle, PostgreSQL, SQL Anywhere, SQLite,...
- Software downloads 2009-07-29
- NConstruct Lite 2.2.0 (Windows)
- NConstruct Lite is a powerful wizard-like tool for creating application's data layer source code for NHibernate object/relational persistence and query framework. NConstruct Lite examines database's metadata and creates NHibernate HBM files, entities' source code, Microsoft Visual Studio project file, and some optional helper files. NConstruct Lite is a derivative of...
- Software downloads 2009-07-17
- Quickly and Easily Identify Server Bottlenecks to Improve Database Performance and Application Response Times
- For DBAs and developers, Ignite goes further than any tool to find the source of SQL Server bottlenecks - enabling them to quickly find and fix performance problems. SQL Server Database Administrators DBAs and developers need to optimize existing IT infrastructure to meet service level agreements. They also need to...
- Case studies 2009-06-17
- Oracle Office, MySQL, and other dreams
- Oracle Office, MySQL, and other dreamsIt also allows Oracle to take baby steps towards the world where databases become a commodity. They will be already are moving up the chain to applications.In the transition, Oracle will have the number one commodity database with the best monetization strategy, and be able...
- Discussion threads 2009-05-02
- Advanced Database Query 1.5 (Windows)
- Advanced Database Query is a relational database client utility that allows execution of SQL Structured Query Language statements on Microsoft SQL Server and MySQL databases. Resultsets returned by select statements are automatically persisted as CSV Comma Separated Values spreadsheets to a directory of your choice. The application automatically persists most...
- Software downloads 2009-03-15
- SQL Sets Standard Edition 1.1 (Windows)
- SQL Sets allows you to quickly capture and organize snapshots of your SQL Server data into a single, self-contained file called a Portable Data Document. In conjunction with the free SQL Sets Reader, these files allow for easy sharing of and collaboration on relational data with team members and business...
- Software downloads 2009-03-06
- Advanced SQL To RTF Table Converter 1.5 (Windows)
- Advanced SQL To RTF Table Converter is a relational database client utility that allows execution of SQL Structured Query Language statements on Microsoft SQL Server and MySQL databases. Resultsets returned by select queries are automatically persisted as RTF Rich Text Format files to a directory of your choice. RTF files...
- Software downloads 2009-02-04
- Advanced SQL To PDF Table Converter 1.5 (Windows)
- Advanced SQL To PDF Table Converter is a relational database client utility that allows execution of SQL Structured Query Language statements on Microsoft SQL Server and MySQL databases. Result sets returned by select queries are automatically persisted as PDF files to a directory of your choice. Advanced SQL To PDF...
- Software downloads 2009-02-04
- Advanced SQL To HTML Table Converter 1.5 (Windows)
- Advanced SQL To HTML Table Converter is a relational database client utility that allows execution of SQL Structured Query Language statements on Microsoft SQL Server and MySQL databases. Resultsets returned by select queries are automatically persisted as HTML and CSS table files to a directory of your choice. Advanced SQL...
- Software downloads 2009-02-04
- Our new business/technology curriculum
- Our business department is undergoing some shifts next fall due to changing budgets, retiring staff, and a technology director (that's me) who would like to see the way we teach computing. Up until now, aside from a web design class (introductory HTML, WYSIWYG tools, design principles, etc.), we've largely...
- Blog posts 2009-02-03
- Advanced SQL To XML Query 1.5 (Windows)
- Advanced SQL To XML Query is a relational database client utility that allows execution of SQL Structured Query Language statements on Microsoft SQL Server databases. Result sets returned by select statements are automatically converted to XML files and persisted to a directory of your choice. The application automatically persists most...
- Software downloads 2009-01-30
Neighboring Terms
Premier Vendor Content Whitepapers, webcasts & resources from our Power Center Sponsors
- Microsoft Dynamics CRM Online - Free Six-Month Trial for Eligible Organizations
-
Microsoft Dynamics CRM Online provides fast online access, simple contact management and better sales performance for a low monthly cost - the best value on the market today.
- Learn more about the free, six-month trial offer>>
- Save time with automated shipping solutions
-
The Business Essentials Guide provides you useful tools and templates to help grow your business and save you time with automated shipping solutions.
- Visit the UPS Business Essentials Guide
- Keep Up With The Latest In Document Management with The DocuMentor.
-
Doc delivers the scoop on today's enterprise content management, printer maintenance, and all other issues related to document management. It's the DocuMentor Blog.
- Learn more >>
SmartPlanet
- Thought-provoking progressive ideas on diverse topics that intersect with technology, business, and life, and matter to the world at large. Visit SmartPlanet
- More from IBM
-
- How to Drive Better Business Outcomes with Exceptional Web Experiences Download the eBook
- Driving Business Agility through SOA Connectivity & Integration Read the White Paper from IBM
- Linking Decisions and Information for Organizational Performance Read the Tom Davenport study
