/* MySql Version, Variables, and where the data Files are ------ */

SELECT version();
SHOW   variables LIKE "%version%";
SHOW   variables WHERE variable_name='datadir';
SHOW   variables;
SHOW   processlist;


/* Oracle Version and Variables ----------------------------------- */

SELECT banner FROM v$version;

SELECT SYS_CONTEXT('userenv','instance_name') FROM dual;
SELECT SYS_CONTEXT('userenv','db_name')       FROM dual;
SELECT SYS_CONTEXT('userenv','server_host')   FROM dual;

SELECT *                                    FROM v$instance;
SELECT instance_name, version, version_full FROM v$instance;

SELECT *                   FROM v$database;
SELECT name, platform_name FROM v$database;


/* PostgrSQL Version ---------------------------------------------- */

SELECT version(); 


/* SQLite Version ------------------------------------------------- */

SELECT sqlite_version();