SQL Links

A search engine can find thousands of SQL sites in a second. We humans took twenty hours to select the top twenty. Categories are:
DOWNLOADS: Companies which produce SQL databases or SQL-related programs, and which allow downloads of real working programs;
CHAT ROOMS / DISCUSSION GROUPS: For timely and real SQL news, or for questions about various SQL dialects.
STANDARDS: Both government and private bodies which produce SQL-related standards.

DOWNLOADS:
Open-source projects include: ArunaDB (written in Ruby, hard to download), CQL, Firebird (a fork from InterBase 6.0), Gadfly (for Python fans only, orphaned), Gnu SQL (hasn't been updated recently), InterBase 6.0 (Borland's orphan), MySQL from MySQL AB, THE OCELOT SQL DBMS (ISO standard SQL), PostgreSQL (one of the few implementations that supports UDTs), SAP (from a large German company), SQLite (public domain C code).
Java open-source projects include: hsql, McKoi, Quadcap.
Free downloads without source, and free downloads of evaluation versions, include: IBM DB2 (free for evaluation), Microsoft's MDAC 2.6 (SDK includes ODBC parts), Microsoft's ODBC 3.0 (obsolete but complete), Oracle (30-day trial but you have to join up), Yard (free for educational purposes), InstantDB (yet another Java starter), mimer (linux from Sweden reasonably standard), Ovrimos, and mSQL (formerly miniSQL, no longer free), Sybase 11.9.2 for Linux (free but not the latest version).
ODBC applications are abundant. You can find lists of them at zdnet (search for ODBC), or download (search for ODBC).
Web-course sites include: Interactive/On-line SQL Tutorial (You can enter SQL statements on the web and get html feedback but many standard SQL statements won't work). Also you can download GISQ, but we have had bad experiences with the author of this site.
Articles include: PC Magazine's 1999 review of the top five (IBM, Informix, Microsoft, Oracle, Sybase), idug magazine's 1998 warning about the threats to SQL progress, or ZDnet's dick-and-jane piece. For old academic articles you can try research index and search for SQL.
For an ongoing online magazine, we like dbazine.com.

CHAT ROOMS OR DISCUSSION GROUPS:
There are several vendor-specific discussion groups; the best-known generic ones are on yahoo, and Tek-Tips. Use deja to peek at current discussions (search for SQL).

STANDARDS:
The FTP archive for ISO or ANSI standards committees' minutes and memoranda is sql-99.org (but it's been down for several weeks now). The in-progress drafts for the SQL:2003 standard are at sqlstandards.org. A large but somewhat dated SQL conformance test suite is at NIST. Java programmers should download the JDBC 3.0 spec and test suite from Sun.