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20. TRIM Function

Which SELECT statement will the result 'elloworld' from the string 'HelloWorld'?

A. SELECT SUBSTR( 'HelloWorld',1) FROM dual;
B. SELECT INITCAP(TRIM ('HelloWorld', 1,1)) FROM dual;
C. SELECT LOWER(SUBSTR('HellowWorld', 1, 1) FROM dual;
D. SELECT LOWER(SUBSTR('HelloWorld', 2, 1) FROM dual;
E. SELECT LOWER(TRIM ('H' FROM 'HelloWorld')) FROM dual;

Answer: E

Explanation:
TRIM function accept a string describing the data you would like to trim from a column value. It can trim from both side of column value i.e. left and right. In the following statement this functionwill trim as
SELECT LOWER(TRIM ('+' FROM 'HelloWorld')) FROM dual;

From the above statement trim function will remove the character 'H' from 'HelloWorld' and LOWER function will convert the remaining character to lower case.

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