I have a doubt about connection between two systems.
System1: Z/OS mainframe, Cobol/DB2.
System2: AIX server, Oracle 9i
In system1 I need data from system2 (Oracle database). I need data from three tables (three sqls) one of the table has 5 millions records, and my sql will ask for 1 million (aprox). Im thinking in using a Oracle client installed in system1 (Z/OS) that will connect with Oracle server in system2. Is that possible???,I have never done anything similar, is there any disadvantage in this architecture??, other options??. My other option is exchanging flat files with the data between the two systems. I dont like very much, because the applications may grow and need more data, and that will mean more files.

Any help, advice, will be greatly appreciated.
Thanks in advance