Which three tasks can be performed using SQL functions built into Oracle Database?
A.
displaying a date in a nondefault format
B.
finding the number of characters in an expression
C.
substituting a character string in a text expression with a specified string
D.
combining more than two columns or expressions into a single column in the output
A. select TO_CHAR(sysdate, ‘Day Month Year’) from dual;
B. select LENGTH(‘asdf’) from dual;
C. select SUBSTR(‘abcd’, 2) || ‘ specified string’ from dual;
A, B, C are corrects.
D – CONCAT accept only two parameters.
Ex:
SELECT CONCAT(‘content1’, ‘content2’) FROM DUAL;
or
SELECT CONCAT(‘content1’ || ‘ ‘ || ‘content2’, ‘content3’) FROM DUAL;
ERROR:
CONCAT(‘content1’, ‘content2’, ‘content3’) FROM DUAL;
D – can only be done using LISTAGG function Oracle SQL