query your db
SELECT * FROM V$VERSION;
out put
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 – 64bit Production 0
PL/SQL Release 12.1.0.2.0 – Production 0
“CORE 12.1.0.2.0 Production” 0
TNS for Linux: Version 12.1.0.2.0 – Production 0
NLSRTL Version 12.1.0.2.0 – Production 0