There is one SQL tutor on the net at http://w3.one.net/~jhoffman/sqltut.htm
This one has been recommended by a lot of people on the MySQL mailing list.
Judith S. Bowman, Sandra L. Emerson and Marcy Darnovsky "The Practical SQL Handbook: Using Structured Query Language" Second Edition Addison Wesley ISBN 0-201-62623-3 http://www.awl.com
And another book also recommended by people on the MySQL mailing list.
Understanding SQL ISBN 0-89588-644-8 Publisher Sybex 510 523 8233 Alameda CA USA
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