SQL Links
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Links last updated: 2007-03-31
SQL
SQL Performance Tuning: Simple Searches
Chapter 2 of SQL Performance Tuning (ISBN 0201791692) by Peter Gulutzan and Trudy Pelzer
An excellent, in-depth analysis of search SQLDate Handling: Hacks 19-23 (PDF)
Chapter 4 of O'Reilly's SQL Hacks by Andrew Cumming and Gordon Russell.
Hack 23, "Second Tuesday of the Month," by Rudy Limeback.A Gentle Introduction to SQL
This is a fabulous site which allows you to test your SQL in various dialects. (Site was formerly http://www.dcs.napier.ac.uk/~andrew/sql/)DBMS Magazine Articles [ by Joe Celko ]
Articles from the SQL for Smarties column 1996-1998Mimer SQL Developers - Mimer SQL Validator
Mimer SQL - embedded, scalable, database solutions conforming to ISO standards and suited for open environments.
Free service to let you validate your SQL against different SQL standards -- excellent online resourceSQL Tutorial
SQL Tutorial and SQL Reference. This SQL tutorial aims to teach beginners the building blocks of SQL. This is also a reference site for general SQL commands.
Fairly comprehensive tutorial, but there are just way too many ads!!SQL Topics
SQL Topics
Examples of various SQL statements and constructsViews
Chapter 12 of Sybex's Database Design for Mere Mortals, by Michael J. Hernandez, ISBN: 0201694719sqlblindman - SQL
Code samples and articles on SQL Database methods and practices.Ask The Expert: SQL
Links to my Ask The Expert answers (10 per page)SQL Reserved Words Checker
Enter a word or keyword and the checker will check to see if it is in the SQL Server, MySQL, PostgreSQL, Oracle, DB2, ANSI SQL, or ODBC reserved words listThe art of SQL: Recognizing classic SQL patterns
Excerpt from Chapter 6 of The Art of SQL by Stephane Faroult with Peter Robson, published by O'Reilly Media Inc. in 2006.Structured Query Language (SQL)
Miscellaneous SQL linksNo Need to Get ANSI about SQL 99 Join Syntax
from the oracle perspectiveSELECT Statement: The GROUP BY Clause in SQL
Chapter 10 of "Introduction to SQL: Mastering the Relational Database Language, 4th Edition" by Rick F. van der Lans (ISBN 0321305965)
Very comprehensive GROUP BY tutorial.Mythbuster: Normalizing with Integers is Always Best: ASP Alliance
SQLRef.Com
Another very basic intro.Dave's guide to the EAV
A comprehensive analysis of the difficulties involved in setting up an EAV design.O'Reilly Network: aboutSQL
Dedicated to getting you into SQL and saving you development time and effort, John Paul Ashenfelter's aboutSQL provides information on SQL keywords, functions, tricks, and hacks.
discontinued in 2001SQL - Wikipedia, the free encyclopedia
Includes history and standards informationSQL Injection Attacks by Example
There have been other papers on SQL injection, including some that are much more detailed, but this one shows the rationale of discovery as much as the process of exploitation.Open Directory - Computers: Programming: Languages: SQL: FAQs, Help, and Tutorials
MySQL Manual | 3.6.4 The Rows Holding the Group-wise Maximum of a Certain Field
The Select Star Problem
From the perspective of Java classes.Path Enumeration using Prime Number Products
another model for storing a hierarchy in a relational databaseStored procedures are bad, m'kay?
Another "religious war" article, with a few hundred comments.Additional Criteria in the JOIN Clause - SQLTeam.com
Have you ever seen a SELECT statement joining two tables that had something like "and Field = Value" in the JOIN clause? Why did they put that in the JOIN instead of in the WHERE clause? What difference does it make?Data Security: Stop SQL Injection Attacks Before They Stop You -- MSDN Magazine, September 2004
Relational Algebra
Chapter 5 from "Designing Relational Database Systems" by Rebecca M. Riordan
Topics include: Nulls and Three-Valued Logic (One More Time), Relational Operators, Set Operators, Special Relational OperatorsGenerate Test Data Quickly With Cross Joins
Need to rough up some bulk test data in a hurry? A carefully thought-out Cross Join could be the answer.Sql lernen - ein Tutorial zum Selbststudium mit einer Beispiel-Datenbank
SQL tutorial in German, with example databaseSql lernen - ein Tutorial zum Selbststudium mit einer Beispiel-Datenbank
Sql = Structured Query Language, die Sprache zum Abfragen und Bearbeiten von Datenbanken: Lernen Sie diese im Selbststudium.SQL:ᅠᅠᅠFeatured Topics:ᅠᅠᅠExpertAnswerCenter.com
This is my "SQL blog" which ran for two weeks on the Expert Answer Center at TechTarget.com.Trees and Hierachies in SQL: Adjacency List Model
by Joe Celko
excerpt from Chapter 2SQL Tutorial
SQL is a standard computer language for accessing and manipulating databases.
Very basic intro. Includes a test.it-torino-java-jug : Message: Why "select star" is bad?
In Italian.SQL Queries and the Single Quotation Symbol Problem
When two single quotes appear together, they are interpreted by SQL as one literal single quote.SQL Tutorial
If you are looking for a SQL tutorial, this is the site. Our SQL tutorial provides the help you need to get started using SQL. It covers the create, import, retrieve, order, update, delete, insert, and join commands.SQL at Xaprb
Excellent technical blog, fabulous SQL category.SQL:1999, formerly known as SQL3
Google cache HTML version of the file http://www.cs.sfu.ca/ CC/354/oschulte/ standards.doc by Andrew Eisenberg and Jim Melton.SQL Reference and Example Site
SQL Reference and Example Site * featuring * Cinema SQLDatabase Portability: Date and Timestamp Columns
This page provides a quick index of which data types are used for storing date/timestamp/datetime information and how to get each DBMS to accept ISO formatted input and produce ISO formatted output.Tips on Writing Portable SQL for Multiple Databases for PHP
Includes the example of 5 different ways to retrieve 10 rows for paging purposes in 7 different databases.SQL Forum
low volumeHierarchical SQL
Excerpt from chapter 3 of Celko's new book, "Trees & Hierarchies in SQL for Smarties"SQLCourse2 - Advanced Online SQL Training
Advanced Online SQL Training
This is the "sequel" to the SQLCourse.com tutorial.Getting ANSI About Joins
This article discusses the new ANSI join formats including NATIVE, CROSS, and OUTER and includes examples for review and comparison to the "traditional" join mechanisms.The Formula Used to Calculate Ratings
true Bayesian estimate formulaSQL Articles (informIT)
Links to all SQL articles on the InformIT site. Lots of good reading.SQL Injection Attacks
8MB mp3Getting Your Quotes Right In SQL For ASP - The Web Developer's Journal
Getting Your Quotes Right In SQL For ASP - The Web Developer's JournalSQLCourse - Interactive Online SQL Training for Beginners
SQLCourse.com: an interactive online training course for SQL beginners.GalaXQL - Interactive SQL tutorial
Download executable hands-on tutorial (with built-in sql engine)SQL In Simple English - Part I
This article explains the basics of SQL as a Q&A session. Most of the questions are the ones that most novices would like to ask. This approach is excellent and readers who are not familiar with the technology. Since this article is totally language nKihlman's SQL (Graphic SQL tutorial)
The program is designed to help you master SQL statements. It can be used as an interface against a database. You can also do the test taking you through different levels of difficulty.
The program is shareware and free for private use at home.Database eLearning
topics include SQL, Database Analysis and ER Modelling, Normalisation, Relational Algebra, and moreHow to handle a Many-to-Many relationship with PHP and MySQL
Temporal Support in Standard SQL
cattle in pens and star cataloguesSQL Reserved Words Overview
Reserved words in SQL-92, SQL-99, and SQL-2003.DBAzine.com: Molecular, Atomic and Sub-atomic Data Elements: Part I
By Joe Celko. Includes code for Parsing a List in a String, using a numbers table.Using opaque primary keys in data model
"opaque" == surrogateIntroduction to Structured Query Language Version 4.67
by James HoffmanSet Operations
By Joe Celko
Explores the UNION operator.Standard SQL
Do IBM, Microsoft, and Oracle support the SQL:1999 standard? And will they support the SQL:2003 standard as well?SQL Naming Conventions
Covers IBM, Microsoft, Oracle. Includes links to other articles about naming conventions.Filling in the Gaps
Detecting gaps in ranges of numbersTrees in SQL: Nested Sets and Materialized Path
Extremely complex and detailed analysis of several encoding mechanisms for hierarchical data. Definitely worth reading if you want to use anything other than the plain old adjacency model.Tree Denormalization (PDF)
Avoids iterations when querying tree related data.Getting the Right Data with SQL Joins
Associating tables in SQL is usually a breeze. But what happens when you find yourself looking at the completely wrong set of records and you don't know why?
Discusses inner, left outer, right outer, full outer, cross, and self-joins.Why Select * is bad - adOpenStatic.com
Includes reasons specific to ASP/Access but the advice is still good for other platformsStandard SQL
Do IBM, Microsoft, and Oracle support the SQL:1999 standard? And will they support the SQL:2003 standard as well?SQL Tutorial
This is a hands-on tutorial. You download a small SQL DBMS from the web (for free), then follow the illustrated exercises.
Peter Gulutzan is the well-respected author of the book "SQL-99 Complete, Really."Transact-SQL Cookbook: Chapter 8: Statistics in SQL
Means, modes, and medians, Standard deviations, Variances, Standard errors, Confidence intervals, Correlations, Moving averages, Weighted moving averages.Is SQL a real standard any more?
History of standard SQL and analysis of vendor conformanceSQL 92 Standard
Curious what an SQL standard might look like? Have a look at this draft document.
MySQL
Importing Data into MySQL
Techniques and strategies, including what to watch out for (duplicates, etc.)Bob's World: A Million Tables
Maximum number of tables in a MySQL database?3.6.4 The Rows Holding the Group-wise Maximum of a Certain Field
Summaries and NULL Values
Excerpt from Chapter 7, Generating Summaries, of O'Reilly's MySQL Cookbook by Paul DuBoisComputing Team Standings
excerp from Chapter 12, "Using Multiple Tables," of O'Reilly's "MySQL Cookbook" by Paul DuBoisUnderstanding SQL Joins
Written for MySQL but applicable to any database. Inner, cross, left and right outer joins. Doesn't actually use INNER syntax. Nice examples.Optimizing MySQL Queries
Very good, in-depth articles.The Data Charmer: Seeking alternatives to cursors
example of a BLACKHOLE tableUsing AUTO_INCREMENT Values to Relate Tables
excerpt from Chapter 11, "Generating and Using Sequences," of O'Reilly's "MySQL Cookbook" by Paul DuBoisOptimizing your MySQL Application
Is databasing your site slowing it down? Get it zipping along again with Mike's tutorial on MySQL's internal turbo-charger, indexes.Managing Hierarchical Data in MySQL
by Mike Hillyer
Discusses both adjacency and nested set modelsFAQTs - Knowledge Base - faqts : Computers : Databases : MySQL
The MySQL SET Datatype
By Mike Hillyer
SET is like ENUM -- evil, but occasionally useful.Counting and Identifying Duplicates
excerpt from Chapter 7, "Generating Summaries," of O'Reilly's "MySQL Cookbook" by Paul DuBoisA Diagram of the MySQL information schema
Includes client-side image map with links to the various INFORMATION_SCHEMA pages in the MySQL docs.MySQL Stored Procedure Development
This site gives tutorials, advice and support for Stored procedures and functions within MySQL. There is a forum where you can exchange tips and tricks or get help with your stored procedures.How to handle a Many-to-Many relationship with PHP and MySQL
phlab >> MyMan
MyMan is a shortcut for MySQL(TM) manual and it is conversion of this manual into Microsoft HTML Help.Migrating from Microsoft Access to MySQL
by Paul DuBois
SQL Server
CAST and CONVERT
I *always* have to look up the style codes for the various date formats. Talk about counter-intutive.ASPFAQ 3.0 -- database category
Many common SQL questions amongst the numerous ASP and SQL Server onesWorking with hierarchical data in SQL Server databases
Uses a recursive stored proc.TSQL Solutions - Concatenating row values in T-SQL
Comprehensive analysis of various methods to do what MySQL's GROUP_CONCAT does so simply.SQL Server Database Index Performance
Excellent article that covers all the different types of indexes (clustered, composite, covering, etc.) with good links to other excellent articles.Medians, ROW_NUMBERs, and performance
By Adam Machanic.Ordering guarantees in SQL Server...
The optimizer reserves the right to ignore the ORDER BY clause in a view definition if doing so will create a more efficient plan.Adam Machanic
New blog replacing his earlier blog on SQLJunkies.Query Express
Query Express is a simple Query Analyzer look-alike, but being small and free it can be run where the SQL Server client tools are not installed or licensed. This makes it especially useful as a query tool for MSDE and SQL Express. It also connects to Orac
More than 300 times smaller than SQL Server Management Studio!SQL Server Stored Procedure Basics
This sample chapter is excerpted from The Guru's Guide to SQL Server Stored Procedures, XML, and HTML by Ken Henderson.Identity Crisis
The difference between @@IDENTITY and SCOPE_IDENTITY#2120 : How do I page through a recordset?
Ten different approaches to the paging problem
Excellent. Simply excellent.Detecting "Runs" or "Streaks" in your data
It can be difficult in a set-based language such as SQL to determine when a number of records in a row (when ordered by a unique key) have the same values in a particular field.FREETEXT Searches with SQL Server and ADO.NET
MSDE doesn't support FREETEXT searchingMS SQL City
Very DBA-oriented.What are the main differences between Access and SQL Server?
The Beatles versus the Stones
Clustering index does not guarantee result set order.To SP or not to SP in SQL Server: an argument for stored procedures
by Adam MachanicSQL Server Bible: Covering Indexes ScreenCast
"Screencast" with powerpoint slides and audio track. Really very well done.adam machanic :: data manipulation for fun and profit : Running sums, redux
Dynamic Search Conditions in T-SQL
Very detailed analysis of the best ways to write dynamic Transact SQL to enable optimum performance. Quite well written.SQL Server Developer Center: Moving Your Access 2002 Database to SQL Server 2000
SQL -- The Code Project - Free Source Code and Tutorials
Code snippets contributed by community members.Stored procedures are bad, m'kay?
Another "religious war" article, with a few hundred comments.Data Security: Stop SQL Injection Attacks Before They Stop You -- MSDN Magazine, September 2004
Demystifying the SQL Server DATETIME Datatype -- Page One
DATEADD(d,DATEDIFF(d,0,GETDATE()),0)SQL Server Transact-SQL Query Performance Tuning and Optimization Tips
DevGuru Transact-SQL Syntax Charts
Uses DHTML popups to explain syntax elements.SQL Server Database Coding Conventions, Best Practices and Programming Guidelines
MDX at First Glance: Introduction to SQL Server MDX Essentials
Working with Dates
SQL Server has respectable facilities for storing, calculating, and reporting time and date information.123 TSQL functions
This is a collection of 123 TSQL functions.
Includes number to wordsSpeed Up SQL Server Apps
Learn 10 useful tips and tricks that help boost SQL Server application performance -- and streamline development and deployment as well.Pass Arrays To SQL Server
Have you ever needed to pass a multi-dimensional array as an input parameter to a SQL Server stored procedure?SQL Server Database Performance Tuning Tips
Performance tune and optimize your Microsoft SQL Server 6.5, 7.0 and 2000 databases. Articles and hundreds of tips to make your databases faster.Calculating Running Totals
Is there a way to retrieve a field value from the previously read row in order to use it to calculate a field in the current row?More Trees & Hierarchies in SQL - SQLTeam.com
Hierarchies (things like trees, threaded forums, org charts and the like) are sometimes difficult to store in SQL tables. Here's a method that's easy to understand and maintain, and gives you the full hierarchy (or any piece of it) easily.What are the main differences between Access and SQL Server?
How to Perform a SQL Server Database Application & Transact-SQL Performance Audit
Achieving better performance with MS SQL Server
Clustered indexes, non-clustered indexes, covering indexes, indexed views...Stump the SQL Guru!
Seems that they stopped answering questions in early 2002, but a couple dozen old answers are available.Advanced SQL Techniques - Part 1: Analyzing Duplicate Records
In the first of this four-part series, David Penton describes a quick and efficient way to delete duplicate records from a table.Speed Tips For SQL Server SELECT Statements
Learn how to speed up your SQL Server SELECT statements.SQL: Limit Rows Returned
describes a method to enable limiting rows returned in stored procedures without impacting live queriesSQL Server (MSDE) on Win 98
Includes instructions for how to install MSDE
Data Modelling
Database Design - Many-to-many
Uses "junction table" terminology. Excellent diagrams.Introduction to Entity-relationship modelling
Cardinality, existence, subtypes, ...Relational Data Architecture
Chapter 2 of O'Reilly's Java Databases Best Practices by George Reece
Covers ER modelling, normalization, and denormalization, using better than average examplesData Modeling 101
Includes overview of data modelling notations: IE, Barker, IDEF1X, UML.Business Rules Community, the world's most trusted resource for business rule professionals
Vertical community for business rule practitioners. Hosted by Business Rule Solutions, home of some of the world's leading experts and practitioners in the field of business rules.
Ronald G. Ross et al. Requires free registration.Rules of Data Normalization
Graphics are poor or missing13 reasons why normalized tables help your business
News and advice for IT professionals working with database software and tools.Database Normalization Basics
Windows Streaming Media, 22 minutesIntroduction to Relational Databases - Part 1: Theoretical Foundation
The first article in this two-part series provides a basic understanding of the theoretical principles of database design and describes some key elements and rules of creating relational databases.
Includes Codd's 12 rules and normal forms up to 5NF and DKNF.Lookup Table Madness
MUCK = massively unified code-key (i.e. similar to OTLT = one true lookup table)Dave's guide to the EAV
A comprehensive analysis of the difficulties involved in setting up an EAV design.Tony Andrews on Oracle and Databases: OTLT and EAV: the two big design mistakes all beginners make
CELKO on identity columns
Splendid long article on the dangers of using an IDENTITY column as a surrogate key.Pros and Cons of Surrogate Keys
Excellent examples using actual SQL to show differences between surrogate and natural key designs.Trees and Hierachies in SQL: Adjacency List Model
by Joe Celko
excerpt from Chapter 2A categorization of data models
Blog by Certus.Five Ms of Meta Data
very comprehensive and clear article about meta data solving real issues in data warehousing and business intelligenceManaging Hierarchical Data in MySQL
by Mike Hillyer
Discusses both adjacency and nested set modelsAn Introduction to Database Normalization (MySQL AB)
By Mike Hillyer.Database Portability: Date and Timestamp Columns
This page provides a quick index of which data types are used for storing date/timestamp/datetime information and how to get each DBMS to accept ISO formatted input and produce ISO formatted output.Database Normalization
As your database projects grow, you may start finding that the original design of your tables is proving problematic. The SQL you write starts to become unwieldy, and data anomalies start to creep in.Concepts of Database Design and Management
Spending time designing the initial structure of a Database will ensure that future problems will be kept to a minimum. Jason explains how to quickly and easily ensure you have the necessary fields in your Database.ColdFusion MX Coding Guidelines - Release 3.0.2 (10/17/2003) - Database Conventions
Table and column naming conventions.SQL by Design: Supertypes and Subtypes
Persons, employees, supervisors, customersIdentity and Primary Keys
You may think that a primary key and an Identity/Autonumber column are the same thing. Well, they're not, and there are some very good reasons NOT to use an Identity column for the primary key on your tables.An Argument Against IDENTITY
Nice long discussion thread about candidate keys, etc.The Case for the Surrogate Key
SQLTeam.com discussion threadOne to many and many to many relationships
By Joe CelkoTopic: Database Design - SQLTeam.com
Index page for various SQLTeam articles dealing with database design.Introduction to Data Modeling
Information Technology Services at The University of Texas at Austin.
Excellent tutorial.The Importance of Data Modeling
What is Data Modeling? Why is it important? This series of articles explains what data modeling is, why you should use it, and how to do it! A must read for anyone who needs to design a relation data model!Keys and History
Let's ditch the punch cards once and for all (by Joe Celko)
Defines natural key, artificial key, "uniqueifier", surrogate key.Entity Relationship Modelling - 2
Includes "fan" and "chasm" traps.Database Systems and Structures
Notes/slides from a college courseThe Puppy Poster
PDF of a poster from 1989, DB Programming and Design magazine.A Simple Guide to Five Normal Forms in Relational Database Theory
1NF through 5NFData Modeling (part of SQL for Web Nerds)
Somewhat dated, introductory level, but quite entertaining.Core Database Concepts
Sample chapter from the glasshaus book "Practical Web Database Design" by Chris Auld, Allan Kent, Rudy Limeback, Nigel Stanger, Thearon Willis.
Data models, primary and foreign keys, normalization, etc.Key Issues - Surviving SQL
primary keys, surrogate keysUsing opaque primary keys in data model
"opaque" == surrogateInformation Resource Management Association of Canada (IRMAC)
Toronto-based user group for exchanging information and experiences involving all aspects of data administration, data warehouse and information resource management.A Dimensional Modeling Manifesto
By Ralph KimballData Modelling Tools
Lists a couple dozen tools, with recommendations.Database Normalization And Design Techniques
Covers 1NF through 4NF with examples.Data Schema Normalization
1NF through 5NF including BCNF, EKNF, PJNFDatabase Design Principles
Chapter 4 of O'Reilly's Access Database Design & Programming, 3rd Edition, by Steven Roman
Covers 1NF, 2NF, 3NF, BCNFEnhanced E-R Model
Subtypes and supertypes, business rule onstraints.Entity Relationship Modeling
By Alf PedersenChapter 4: Database Design Principles
excerpt from O'Reilly's Access Database Design and Programming, by Steven Roman, ISBN 1-56592-626-9, 1999
Covers 1NF through BCNF
Data Management
Business Intelligence Network: BI & Data Warehousing Resources
Business Intelligence Network delivers business intelligence, data warehousing and analytics resources provided by Claudia Imhoff, Bill Inmon and other experts.Chapter 17: Data Warehouse Design Considerations
Sample Chapter from Microsoft SQL Server 2000 Resource Kit
Data Warehouses, OLTP, OLAP, Data Mining, Dimensional Models, Dimension Tables, Fact Tables, OLAP Cubes, Operational Data StoresBrint.com
The Premier Business Technology Knowledge Portal and Global Community Network for E-Business, Information, Technology, and Knowledge Management
was http://www.pitt.edu/~malhotra/interest.html, "a business researcher's interests"The Data Warehousing Institute
Business Intelligence and Data Warehousing Education, Research, and CommunityInfoWorld: Data management TechIndex
Heavily oriented towards technology.Business Intelligence and Data Warehousing - TDWI
TDWI is the premier provider of in-depth, high quality education and training in the Business Intelligence and data warehousing industry.dataWarehouse.com
Topics like CRM, ERP, databases, data quality, data visualization and e-commerce/e-businessThe Data Warehousing Information Center
This site is a collection of one practitioner's essays on data warehousing, decision support, business intelligence, or whatever you want to call it.
was http://pwp.starnetinc.com/larryg/index.htmlKimball Group: Data Warehouse Training: Articles
Ralph Kimball and other Kimball Group members have written over 120 columns for Intelligent Enterprise Magazine and its predecessor, DBMS Magazine.Related Sites [ for Decision Support Systems, Data Warehousing, etc. ]
Decision Support Systems, Expert Systems and Artificial Intelligence, Knowledge Management
Database
Troels' links: Relational database systems
With a focus on SQL-standards and open source softwareDatabaseCorner.Com - Database Software Directory
Knowledge Base and Software Directory about Database Management SystemsFirebird - The RDBMS that's going where you're going
Firebird is a relational database offering many ANSI SQL-92 features that runs on Linux, Windows, and a variety of Unix platforms.Database-Related Web Sites and Links
Links to DBMS vendors, related tool vendors, database magazines, consultants, organizations, groupsOf Interest
index of recent articles, starting with Joe Celko'sDatabases and Trust
"This database sucks. I'm going to keep my own [data] in Excel."comp.databases.theory
Google groups archive of comp.databases.theory.The comparison of SQL Server 2000 with MySQL v4.1
from the conclusion: "It is not true that SQL Server 2000 is better than MySQL version 4.1 or vice versa. Both products can be used to build stable and efficient systems."A new approach to querying databases?
Tutorial D, a language designed by Darwen and Date as the interface to their new database architectureDatabase Journal: Daily Database News, Information and Tutorials for the Database Professional
Database Journal offers daily database news, articles, and tutorials for the database professional. All major DBs are covered, including Oracle, SQL Server, DB2, and Access.Database Server Feature Comparison (by MySQL AB)
Database comparison of MySQL, DB2, MSSQL, Oracle, and PostgreSQL, generated with crash-me, a program that automatically detects the limits and capabilities of an SQL DBMS.Comparing Autonumbering Methods in Different Relational Database Management Systems
Database Performance Philosophy
Longtime 15Seconds discussion list member Tore Bostrup offers valuable advice on designing databases and applications for efficient querying.Practical PostgreSQL
This is an online book, "Practical PostgreSQL" by O'ReillyChapter 12: Database Management Systems
Somewhat dated, introductory level, but quite entertaining.The Third Manifesto
By Hugh Darwen and C.J. DateTimestamps
By Trudy Pelzer
compares DATETIME data type in IBM DB2 v8.1, Microsoft SQL Server 2000, and Oracle9i.Sequences and Identify Columns
Compares SQL:2003, DB2, and Oracle SEQUENCE syntaxSystem Tables
Explains metadata stored in system/dictionary tables (information schema).Cetus Links: 16604 Links on Objects and Components / Object-Oriented Databases: General Information
Database terminology, what is...
What is a key, foreign key, compound key, etc. An explanation and many other database terms...Introduction to Databases for the Web
Excellent overview of database capabilities (the sections on implementation use Perl and Java as examples).IBM Informix Guide to SQL (PDF)
1232 pagesLinux SQL Databases and Tools
A survey of free and commercial Linux SQL databases. Many of these are full-fledged DBMS with features like record locking, BLOB support, hot backups, transaction support, rollback, replication, and include ODBC and JDBC bindings.
Access
Access query language elements
This is a great reference.Access Data Manipulation Language
Access 2003Your First Database
Oriented towards building a Web-based relational database applicationWhat are the main differences between Access and SQL Server?
Grouped Transactional Report Part I
In the first segment of this two-part article, author Bill Pearson begins the step-by-step design of a report that presents transactional customer information, then groups that information at multiple levels with corresponding totals.SQL Server Developer Center: Moving Your Access 2002 Database to SQL Server 2000
Tony's Main Microsoft Access Page
Access tips, hints and linksUse System Tables to Manage Objects
MSysObjectsLeszynski Naming Convention - Wikipedia, the free encyclopedia
Doug's pathetic Microsoft Access page
Microsoft Access LinksQ180841 - HOWTO Common DDL SQL for the Microsoft Access Database Engine
Q209037 - ACC2000 Create and Drop Tables and Relationships Using SQL DDL
dBforums - Access query, comparing times and dates??
This forum thread starts out with the rant "OH MY GOD I SOOOOOOOOOOOO HATE SQL!!!!!!!!!!!!!!!!!!!" and features several people struggling to come to terms with Access date formats. There are some good links in the last post.What are the main differences between Access and SQL Server?
The Truth About Access
When should it be used and when should it not? Members of the 15 Seconds discussion list provide some insight into using Microsoft Access for Web applications.Roger's Access Library
A compendium of useful Microsoft Access samples, knowledge, and links.
Includes sample databases.About using wildcard characters to search for partial or matching values (access replace)
Special characters for searching in Microsoft AccessTutorial: Microsoft Access - Datatypes, Table Processing & Design Layouts
Excellent beginner-level tutorial.Resources For MS Access
Links to Microsoft Access Knowledge Base Articles.DateDiff Function
Visual Basic Scripting Edition
i.e. applies to Microsoft AccessChapter 15: Application Optimization -- Access 2002 Desktop Developer's Handbook
Excerpt from Sybex's Access 2002 Desktop Developer's Handbook by Paul Litwin, Ken Getz, and Mike Gunderloy
Includes "Understanding How the Jet Query Engine Works," an excellent description explaining how joins are handled.
DB2
Expanding Recursive Opportunities with SQL UDFs in DB2 v7.2
Recursion is an extremely efficient technique to resolve tree-like relationships.
Trees and hierarchies, nice diagrams too.DB2 SQL Cookbook
Download an entire book in PDF format.dBforums - Useful DB2 Stuff
Many useful links.
Oracle
Ask Tom
Very frequently updated siteOracle WTF
Inspired by the marvellous www.thedailywtf.com, whose only fault is a shortage of Oracle examples. Well, yes, we could provide some, but we thought we'd do this instead.The story behind the Oracle DATE datatype
Dizwell Informatics - Insight for Oracle
Nice description involving solar cycles, moon phases, golden numbers, julian dates, oh, and some Oracle internals too.SQL tips
orafusion.com: ColdFusion and Oracle TipsOracle FAQ: SQL
Questions and answers about Oracle's implementation of SQL (Structured Query Language).Performing Top-N Queries in Oracle
Use a single SQL statement to perform a top-N query.