-- For Oracle only
-- syntax
SUBSTR(<main-string>,1,<number-of-characters>)
-- example
SUBSTR('Useless stuff',1,10) -- OUTPUT: Useless st
-- practical example
SELECT SUBSTR('Useless stuff',1,10)
FROM DUAL;
-- For Oracle only
-- syntax
SUBSTR(<main-string>,-<number-of-characters>)
-- example
SUBSTR('Useless stuff',-9) -- OUTPUT: ess stuff
-- practical example
SELECT SUBSTR('Useless stuff',-9)
FROM DUAL;