One of my favorite features is the color coded syntax.  This sounds like a very trivial feature.   But for anyone that has written scripts that are a few hundred lines long, this is an invaluable aid.  You can tell immediately if there is a typo that will cause a syntax error you would have to track down.  This also allows you to easily analyze scripts, especially ones generated by a tool since certain blocks of code always have the same basic look.  Given the amount of time that something as simple as color coded syntax saves me, this tool would be worth the money just for the time savings.  As an interesting aside, the new Query Analyzer in Microsoft SQL Server 7 now has color coded syntax.  (We all know how good Microsoft is at copying good ideas.)

The result sets for each query are displayed in a grid that can accommodate up to 2 billion rows.  This is a very nice feature and makes working with result sets rather simple.  Result sets can be exported to spreadsheet formats or even attach them to an email.  There is also the capability to sort result sets in place which can come in very handy.

The email capability is very good.  I'm sure a lot of people have needed to extract the DDL for an object, save it as a file, open you email software, create a message, and attach the file.  With RapidSQL, you simply extract the DDL, hit the email button, and either type in or select the recipient.  The script or result set is automatically added as an attachment and sent as long as you are using a MAPI compliant email system.  This feature has saved me quite a bit of time when sending script updates to the other DBA at my client for inclusion in the upgrade application. 

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