ProDBA The cross platform Oracle development/administration tool written in Java. Features a powerful SQL editor and schema navigator. Can export dynamic queries to the web.
ViennaSQL is a GUI SQL client written in 100% Java. ViennaSQL can communicate with any database that has a JDBC driver. It should run anywhere Java runs.
lib4d_sql is a C library providing the required functions (connect, prepare, execute, ...) to write a SQL client for 4D databases. It uses the public 4D SQL protocol wich is supported by 4D products since... the version 11. It is already used by the PDO_