SQL Developer currently doesn't support proprietary commands of non Oracle databases like SQL Server, Sybase ... . But a new feature call Worksheet Hints allows these commands to be executed. SQL Developers Worksheet has to parse commands to identify their start and finish and their type (query, or update ,... ). We recognize Oracle SQL , PL/SQL and SQL*Plus , but we have yet to work on other databases syntax. So at the moment if you running a command against MySQL, SQL Server or Sybase, it has to be fairly similar to an Oracle statement for it to be recognized and run correctly. EX: SELECT, INSERT,UPDATE,DELETE. Things like MySQL use [databasename] or show databases are not recognized yet. Full MySQL recognition will not make it into SQL Developer 3.0 , but SQL Developer 3 EA2 does allow you to give the Worksheet parser a hint as to what type of statement it is and how to execute it. The hint is placed in front of the command, and the command has to be terminated with a forw...