|File-based Databases||Open Source Databases||Some Commercial Databases|
|Access FoxPro||MySQL PostgreSQL Interbase/Firebird||DB2 Pervasive Oracle MS SQL Server Sybase|
DevShed's Database Essentials is my favorite. Some theory whipped lightly.
James Hoffman has a solid SQL tutorial. Very thorough coverage of the SELECT statement.
An interactive SQL course. You can even try SQL queries from your browser.
SQL for Web Nerds by Philip Greenspun. Complete, well written and highly opinionated (like me!) with Oracle bias.
MySQL cross-tabulation tutorial. This technique works with all SQL servers that support CASE, not merely MySQL.
Interoperable SQL (PDF), discusses portability issues with ODBC and JDBC, by Ken North.
DBAZine is a great DBA resource.
DB Debunk is Chris Date and Fabian Pascal's attempt to fight against the misconceptions of the database industry and to promote the "true" relational way. Intellectually stimulating!
Database Specific Links
IBM DB2A very good database whose greatest strength is that it is developed by IBM (great technology), and its greatest weakness is that it is owned by IBM (other hardware vendors will never recommend it).
FoxProUnder-rated and a good cheap choice. Unfortunately it's owned by Microsoft who are more interested in promoting SQL Server.
Interbase/FirebirdSolid and reliable after many years of commercial use. Released as Open Source in 2000. Every US Army Abrams tank runs Interbase internally.
Microsoft Access/JetCleverly crippled by Microsoft to be functional but not scalable. Your database of last resort.
My personal advice is to avoid using Access if possible. FoxPro is a better and more scalable choice if you need to use a file-based database on the Web.
Microsoft SQL ServerThere is a lot to like about this database. An excellent choice if you are running Windows.
SQL Team are a group of MS SQL experts who write techie articles.
Pivot Tables with T-SQL
MySQLFree and fast. Now comes with optional support for transactions.
Optimizing MySQL by W J Gilmore from DevShed.
OracleThe ultimate in scalability and power. Formerly very pricey, it is now very competitively priced compared to other database products such as MSSQL.
The unofficial Oracle FAQs. Very extensive, but sometimes too much info also!
Ixora's Q&A. Ixora is an Oracle consultancy based in Australia that specializes in performance tuning.
Oracle Users' Co-Operative FAQ is another useful FAQ.
ArsDigita Systems Journal has an extensive list of Oracle articles. Some are quite old, but any article written by Philip Greenspun is witty and informative.
Simulating auto-increment in Oracle using triggers.
Oracle PipeLines: Great PL/SQL tips.
Outer Joins in Oracle.
Differences between Oracle Standard and Enterprise Edition (pdf).
Advanced Replication tips.
Generic Connectivity to other databases.
Implementing Oracle's Single Sign-on in PHP Added 22 May 2004
Pervasive.SQLBased on Btrieve, a robust choice as an embedded database.
PostgreSQLAn Open Source database supported by multiple vendors.
PostgreSQL: Introduction and Concepts by Bruce Momjian (book)
Practical PostgreSQL, O'Reilly book
Performance Tuning - good article
SybaseOnce a contender to Oracle, but they stumbled. Still a member of the leading pack of database vendors.
http://www.palslib.com/ Database links
http://www.linuxinsider.com/databases/ Daily updates
http://searchdatabase.techtarget.com/ Daily updates