Comments: Again, congratulations on this library. I see it, combined with the serialization library , as having the potential to eliminate the need for relational databases in c++ applications. Granted, if the development staff consists of DBAs and Java developers they would not agree to such a thing. However, if you have an application that consists of just c++ code, you could make the argument that relational databases are no longer needed. That would be a great thing, as relational datbases and sql are not c++ friendly. I spent many years writing c++ applications that were simply wrappers over relational datbases designed by DBAs. I've always thought that there had to be a better way. It would appear that you have done just that with this library. Questions: 1) When you add a record to an indexed_set, and it violates the index definition in some way, could you throw an exception, instead of simply replacing the original record? 2) Is there support for mult-key unique indicies. I read in the documenation that you can have more than one unique indice in the definition, but they are unique individually. Question: Can you combine two or more of those unique indice to create a multi-key unique indice. __________________________________ Do you Yahoo!? Yahoo! Finance Tax Center - File online. File on time. http://taxes.yahoo.com/filing.html