For Oracle RDBMS do this:
$ cd $ORACLE_HOME/bin
$ file oracle
oracle: ELF 32-bit MSB executable SPARC Version 1, dynamically linked, not stripped
Thus, this is a 32bit version.It would clearly show whether this is a 32 or 64 bit oracle.
For Solaris OS - see this information
Here
Hope that helps,
clio_usa
OCP - DBA
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