1SELECT FIRST_NAME , SUBSTR(FIRST_NAME, 1 , 3 ) , LENGTH(FIRST_NAME)
2FROM EMPLOYEES ;
1-- substr(string, start, [, length ])
2SELECT substr('Hello World', 1, 3) ; -- Hel
3SELECT substr('Hello World', 4, 5) ; -- lo Wo
4SELECT substr('Hello World', 4); -- lo World
5SELECT substr('Hello World', -3); -- rld