I've an Interbase DB. How do i convert it to SQL Server?

You could utilize SQL Server built-in Data Transformation Services (DTS) in SQL Server 2000 or SQL Server Integration Services (SSIS) in SQL Server 2005.

Try establishing an ODBC DSN for Interbase. Then in DTS / SSIS make use of the Other (ODBC Databases) and also the DSN.

If that doesn't work then find out if Interbase includes a utility to export to text files after which use DTS / SSIS to import the written text files.

The Interbase DB Wikipedia page states it supports OBDC and ADO.Internet, and so i would believe that SQL Server can most likely import this database by itself. I do not get access to an Interbase DB installation to test, but you will probably find these pages useful.

MSDN on import data wizard
MSDN on bulk import command (if Interbase DB can dump a text file)
Article on bulk importing from an ADO.NET supporting source

Hopefully somebody may have direct knowledge about this database and may help. Best of luck!

Should you only have to covert tables and data, that's relatively easy. Only use ODBC driver for InterBase, connect with it and pump the information.

But, if you want business logic too, you can't covert it simply like this. You are able to convert regular tables and sights without an excessive amount of problems. Domain info could be lost but you do not need it in MSSQL anyway. The only issue with tables could be array fields, which you have to become separate tables, but that is not way too hard either.

The issue is conversion of triggers and saved methods, since InterBase uses it's own, custom PSQL language. It's some concepts that aren't the same as MSSQL. For instance, you've methods that may return resultsets, and you should convert individuals to MSSQL functions.

Regardless, it should not be to hard, since you are going from low to high complexity, but you will find no tools to get it done instantly.