Some Useful Queries to know Information about your Oracle Instance

SELECT home_url FROM icx_parameters;

SELECT release_name FROM fnd_product_groups;

SELECT instance_name FROM v$instance;

SELECT multi_org_flag FROM fnd_product_groups;

SELECT version FROM v$instance;

SELECT host_name FROM v$instance;

SELECT instance_name FROM v$instance;

SELECT * FROM product_component_version;

SELECT SUM(bytes)/1024/1024 mb FROM dba_extents;

SELECT wf_core.translate('WF_VERSION') FROM dual;
[OR]
SELECT text FROM WF_RESOURCES WHERE name= 'WF_VERSION';

SELECT patch_level
 FROM fnd_product_installations
WHERE patch_level LIKE '%&Your_Application_Short_Name%';

SELECT *
 FROM v$version;