how to connect SQL server from oracle in SQL developer I have two connections in SQL developer that one of them is SQL server (A) and the other one is oracle (B).
how can I make a database link between this two connections from (B) to (A) to select connection A data from connection B?
The last time I looked (and that's quite a number of years ago), you needed Oracle Gateway to establish such a link.

Just checked, the product is still around: Oracle Database Gateway for SQL Server.