Learn Sql queries and resolve Your troubleshootings

This is a good link where you can learn Sql queries and you can resolve your troubleshooting. To visit this link click on following

Sql Queries and troubleshooting
Sql Queries and troubleshooting

By this link you can learn about how to use group by clause ,aggregate methods in query, having clauses,like operators,Data types and type conversions,Handling null vaulues in query,Data formats and table creation etc.

I hope you will get lot of help in above link. Its good for beginner and database professionals.