SQL MCQ Questions and answers

ANY compares a value with each of the values in a list or results from a query and evaluates to true if the result of an inner query contains at least one row. ANY must be preceded by comparison operators(=, >, <, <=, >=, <>).

Employee table has 10 records and each value in non-NULL SALARY column is unique i.e different. So, in that 10 records one of the record will be minimum which cannot be greater than any nine value of the salary column. Hence the condition
WHERE SALARY > ANY (SELECT SALARY FROM employee)
will be true nine times. So, the COUNT(*) outputs 9.

Another form of INSTR function used in ORACLE is:
INSTR (str, pattern, [starting position, [nth location]]): Finds the starting location of the nth occurrence of pattern beginning in the starting position-th position in string str.
Example: - SELECT INSTR('kolkata', 'a', 1, 2) FROM DUAL;
will output 7 as the starting location of 2nd occurrence of pattern 'a' from starting position 1 in string 'kolkata' is 7.

In the above query INSTR('123321234', '2', 3, 2) will give the output 7 as the starting location of 2nd occurrence of pattern '2' from starting location three in string '123321234' is 7.

Now SUBSTR function becomes SUBSTR('abcdefghij

The ROUND function in SQL is used to round a number to a specified precision. The syntax is:
ROUND (expression, [decimal place])
where [decimal place] indicates the number of decimal points returned. A negative number means the rounding will occur to the digit to the left of the decimal point. For example, -1 means the number will be rounded to the nearest tens.

For above given example, the output would be 50 because the nearest tens of 45.926, is 50.
Taking another example, if we have to round (44.678, -1), the out put would be 40, because the nearest tens of 44.678 is 40.