| 1 |
In which situation does the problem of data inconsistency arise? |
Computer Science/Informatics Practices
Database and file systems |
Easy |
| 2 |
What is a database schema? |
Computer Science/Informatics Practices
Database and file systems |
Easy |
| 3 |
A school stores a student's phone number in the fee file, library file and transport file. Which limitation o… |
Computer Science/Informatics Practices
Database and file systems |
Medium |
| 4 |
In a file system, adding a new field to a file forces changes in every program that reads it. This limitation… |
Computer Science/Informatics Practices
Database and file systems |
Medium |
| 5 |
Which statement about a DBMS is correct? |
Computer Science/Informatics Practices
Database and file systems |
Hard |
| 6 |
A relation STUDENT has 5 attributes and 32 tuples. What is its degree? |
Computer Science/Informatics Practices
Relational data model |
Easy |
| 7 |
In the relational model, a single row of a relation is called a |
Computer Science/Informatics Practices
Relational data model |
Easy |
| 8 |
The set of all permissible values that an attribute can take is called its |
Computer Science/Informatics Practices
Relational data model |
Medium |
| 9 |
A table has degree 4 and cardinality 10. Three new rows are inserted and one column is dropped. What are the … |
Computer Science/Informatics Practices
Relational data model |
Medium |
| 10 |
Which of the following is NOT a property of a relation in the relational model? |
Computer Science/Informatics Practices
Relational data model |
Hard |
| 11 |
A relation has three candidate keys. How many alternate keys does it have once a primary key is chosen? |
Computer Science/Informatics Practices
Keys |
Easy |
| 12 |
Which constraint must a primary key always satisfy? |
Computer Science/Informatics Practices
Keys |
Easy |
| 13 |
In tables EMP(EmpNo, Name, DeptNo) and DEPT(DeptNo, DName), DeptNo in EMP is best described as |
Computer Science/Informatics Practices
Keys |
Medium |
| 14 |
In a SECTION table, RollNo repeats across classes, but each combination of Class and RollNo is unique. What i… |
Computer Science/Informatics Practices
Keys |
Medium |
| 15 |
A row is inserted into ORDERS with CustID = 'C9', but no customer with ID 'C9' exists in CUSTOMER, where Cust… |
Computer Science/Informatics Practices
Keys |
Hard |
| 16 |
Which relational algebra operation extracts only certain columns of a relation? |
Computer Science/Informatics Practices
Relational algebra |
Easy |
| 17 |
Relation R has degree 3 and cardinality 4; relation S has degree 2 and cardinality 5. What are the degree and… |
Computer Science/Informatics Practices
Relational algebra |
Easy |
| 18 |
A has 6 tuples and B has 4 tuples; 3 tuples are common and both are union compatible. How many tuples are in … |
Computer Science/Informatics Practices
Relational algebra |
Medium |
| 19 |
For union compatible relations A and B, what does A − B return? |
Computer Science/Informatics Practices
Relational algebra |
Medium |
| 20 |
Which statement about union compatibility is correct? |
Computer Science/Informatics Practices
Relational algebra |
Hard |
| 21 |
Which of these is a DDL command? |
Computer Science/Informatics Practices
SQL and MySQL basics |
Easy |
| 22 |
Which constraint supplies a value for a column automatically when none is given during INSERT? |
Computer Science/Informatics Practices
SQL and MySQL basics |
Easy |
| 23 |
A column is declared CHAR(10) and the value 'RAVI' is stored. How many characters of storage does the value o… |
Computer Science/Informatics Practices
SQL and MySQL basics |
Medium |
| 24 |
Why is SQL described as a non-procedural language? |
Computer Science/Informatics Practices
SQL and MySQL basics |
Medium |
| 25 |
A column Email has a UNIQUE constraint but no NOT NULL constraint. Which statement is correct? |
Computer Science/Informatics Practices
SQL and MySQL basics |
Hard |
| 26 |
Which command removes a table along with its structure from the database? |
Computer Science/Informatics Practices
DDL commands |
Easy |
| 27 |
Which statement adds a column Fees of type FLOAT to the table Student? |
Computer Science/Informatics Practices
DDL commands |
Easy |
| 28 |
The Name column of Student is VARCHAR(20) and must be increased to VARCHAR(50). Which clause of ALTER TABLE i… |
Computer Science/Informatics Practices
DDL commands |
Medium |
| 29 |
After ALTER TABLE Student ADD City VARCHAR(20); is run on a table that already has 8 rows, what value does Ci… |
Computer Science/Informatics Practices
DDL commands |
Medium |
| 30 |
A student runs DELETE FROM Marks; and then DESCRIBE Marks;. What is the result? |
Computer Science/Informatics Practices
DDL commands |
Hard |
| 31 |
Which query lists names of students whose names start with the letter S? |
Computer Science/Informatics Practices
DML and queries |
Easy |
| 32 |
Which clause is used to show only one copy of each repeated city? |
Computer Science/Informatics Practices
DML and queries |
Easy |
| 33 |
Marks values in a table are 40, 50, 65, 80 and 90. How many rows does WHERE Marks BETWEEN 50 AND 80 return? |
Computer Science/Informatics Practices
DML and queries |
Medium |
| 34 |
Which condition correctly finds students whose phone number has not been entered? |
Computer Science/Informatics Practices
DML and queries |
Medium |
| 35 |
Table Emp has 10 rows, 4 of which have Dept = 'HR'. A user meant to run UPDATE Emp SET Bonus = 500 WHERE Dept… |
Computer Science/Informatics Practices
DML and queries |
Hard |
| 36 |
What does SELECT MOD(29, 6); return? |
Computer Science/Informatics Practices
Math and text functions |
Easy |
| 37 |
What is the output of SELECT LEFT('NETWORK', 3);? |
Computer Science/Informatics Practices
Math and text functions |
Easy |
| 38 |
What does SELECT SUBSTRING('INFORMATICS', 3, 4); return? |
Computer Science/Informatics Practices
Math and text functions |
Medium |
| 39 |
What does SELECT ROUND(3478.56, -2); return? |
Computer Science/Informatics Practices
Math and text functions |
Medium |
| 40 |
What is the output of SELECT INSTR('MISSISSIPPI', 'SS') + LENGTH(TRIM(' AB '));? |
Computer Science/Informatics Practices
Math and text functions |
Hard |
| 41 |
What does SELECT MONTH('2023-11-05'); return? |
Computer Science/Informatics Practices
Date functions |
Easy |
| 42 |
Which function returns the name of the weekday for a given date? |
Computer Science/Informatics Practices
Date functions |
Easy |
| 43 |
What is returned by SELECT DATE('2022-07-19 16:45:10');? |
Computer Science/Informatics Practices
Date functions |
Medium |
| 44 |
Which query lists employees who joined in the month of March of any year, from table Emp with column DOJ? |
Computer Science/Informatics Practices
Date functions |
Medium |
| 45 |
What is the output of SELECT DAY('2024-02-29') + MONTH('2024-02-29');? |
Computer Science/Informatics Practices
Date functions |
Hard |
| 46 |
Which function counts all rows of a table, including rows with NULL values? |
Computer Science/Informatics Practices
Aggregate functions and grouping |
Easy |
| 47 |
Which clause is used to apply a condition on groups formed by GROUP BY? |
Computer Science/Informatics Practices
Aggregate functions and grouping |
Easy |
| 48 |
Column Bonus has the values 100, NULL, 300 and NULL. What does SELECT AVG(Bonus) return? |
Computer Science/Informatics Practices
Aggregate functions and grouping |
Medium |
| 49 |
Table Emp has Dept values A, B, A, C, B, A. How many rows does SELECT Dept, COUNT(*) FROM Emp GROUP BY Dept H… |
Computer Science/Informatics Practices
Aggregate functions and grouping |
Medium |
| 50 |
Which query is valid in SQL for finding departments whose total salary exceeds 50000, considering only employ… |
Computer Science/Informatics Practices
Aggregate functions and grouping |
Hard |