We have already removed oracle_home from a server. Now all we have for the database are the datafiles. Now the apps team needs us to export a schema that used to reside in there. So we have to install fresh oracle home pointing the available datafiles and startup the database. Any guide for steps is greatly appreciated..Please help..
Pl post exact OS and database versions (to 4 digits). You will have to re-install the software following the Install Guide for your OS/database version, then re-install any patches that were applied to the ORACLE_HOME that was removed (why was it deleted ?). Alternatively, if you have another ORACLE_HOME install on another server (same OS and database patch level), you can use OUI to clone that ORACLE_HOME over - see the Install Guide for instructions. One the ORACLE_HOME is installed, you can then open the database.
Another option is to copy the existing database files (assuming they are all consistent) to another server with same OS and Oracle version and see if you can open up the database on that server.
you have to install the same oracle version that was present on the server when database was last up and running. And above it you should be having controlfile, redolog file. Parameter file is also important but if it is not present then you can manually create it. To start the database, for taking export of the schema you require.