Consider the following table named Student in a relational database. The primary key of this table is rollNum.
Student
rollNum | name | gender | marks |
---|---|---|---|
1 | Naman | M | 62 |
2 | Aliya | F | 70 |
3 | Aliya | F | 80 |
4 | James | M | 82 |
5 | Swati | F | 65 |
The SQL query below is executed on this database.
SELECT *
FROM Student
WHERE gender = 'F' AND
marks > 65;
The number of rows returned by the query is _____________.
Consider the relational database with the following four schemas and their respective instances.
Student( $$\underline {sNo} $$ , sName, dNo) Dept( $$\underline {dNo} $$ , dName)
Course( $$\underline {cNo} $$ , cName, dNo) Register( $$\underline {sNo} $$ , $$\underline {cNo} $$ )
SQL Query :
SELECT * FROM Student AS S WHERE NOT EXIST
(SELECT cNo FROM Course WHERE dNo = "D01"
EXCEPT
SELECT cNo FROM Register WHERE sNo = S.sNo)
The number of rows returned by the above SQL query is _____________.
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The primary key of the Student table is Roll_no. For the Performance table, the columns Roll_no. and Subject_code together from the primary key. Consider the SQL query given below:
SELECT S.Student_name, sum (P.Marks)
FROM Student S, Performance P
WHERE P.Marks > 84
GROUP BY S.Student_name;
The number of rows returned by the above SQL query is _____.
water_schemes | ||
---|---|---|
scheme_no | district_name | capacity |
1 | Ajmer | 20 |
1 | Bikaner | 10 |
2 | Bikaner | 10 |
3 | Bikaner | 20 |
1 | Churu | 10 |
2 | Churu | 20 |
1 | Dungargarh | 10 |
The number of tuples returned by the following $$SQL$$ query is _______________.
with total(name, capacity) as
select district_name, sum(capacity)
from water_schemes
group by district_name
with total_avg(capacity) as
select avg(capacity)
from total
select name
from total, total_avg
where total.capacity ≥ total_avg.capacity