MySQL is a multithreaded, multi-user SQL database management system which has more than 11 million installations. This MySQL interview questions guide will help you clear the interview and help you get your dream job in MySQL Programming. the most popular MySQL interview questions that are commonly asked in the interviews by experts. Top MySQL Interview Questions and Answers .
Q1.What is the full form of SQL?
A. Structured Query List
B. Structure Query Language
C. Sample Query Language
D. None of these.
Option B – Structure Query Language
Q2.Which of the following is not a DDL command?
A.TRUNCATE
B. ALTER
C. CREATE
D. UPDATE
Option D – UPDATE
Q3.Which of the following are TCL commands?
A. COMMIT and ROLLBACK
B. UPDATE and TRUNCATE
C. SELECT and INSERT
D. GRANT and REVOKE
Option A – COMMIT and ROLLBACK
Q4.SQL Views are also known as
A. Simple tables
B. Virtual tables
C. Complex tables
D. Actual Tables
Option B – Virtual tables
Q5.Which datatype can store unstructured data in a column?
A. CHAR
B. RAW
C. NUMERIC
D. VARCHAR
Option B – RAW
Q6.Which of the following is not Constraint in SQL?
A. Primary Key
B. Not Null
C. Check
D. Union
Option D – Union
Q7.How many Primary keys can have in a table?
A. Only 1
B. Only 2
C. Depends on no of Columns
D. Depends on DBA
Option A – Only1
Q8.Which data manipulation command is used to combines the records from one or more tables?
A. SELECT
B. PROJECT
C. JOIN
D. PRODUCT
Option c – JOIN
Q9.In which of the following cases a DML statement is not executed?
A. When existing rows are modified.
B. When a table is deleted.
C. When some rows are deleted.
D. All of the above
Option B – When a table is deleted.
Q10.Which of the following statement is true?
A. TRUNCATE free the table space while DELETE does not.
B. Both TRUNCATE and DELETE statements free the table’s space.
C. Both TRUNCATE and DELETE statement does not free the table’s space.
D. DELETE free the table space while TRUNCATE does not.
Option A – TRUNCATE free the table space while DELETE does not.
Q11.What is returned by INSTR (‘JAVAT POINT’, ‘P’)?
A. 6
B. 7
C. POINT
D. JAVAT
Option B – 7
Q12.Which of the following is also called an INNER JOIN?
A. SELF JOIN
B. EQUI JOIN
C. NON-EQUI JOIN
D. None of the above
Option B – EQUI JOIN
Q13._ clause creates temporary relation for the query on which it is defined.
A. WITH
B. FROM
C. WHERE
D. SELECT
Option A – With
Q14._ command makes the updates performed by the transaction permanent in the database?
A. ROLLBACK
B. COMMIT
C. TRUNCATE
D. DELETE
Option B – COMMIT
Q15.How can you change “Thomas” into “Michel” in the “LastName” column in the Users table?
A. UPDATE User SET LastName = ‘Thomas’ INTO LastName = ‘Michel’
B. MODIFY Users SET LastName = ‘Michel’ WHERE LastName = ‘Thomas’
C. MODIFY Users SET LastName = ‘Thomas’ INTO LastName = ‘Michel’
D. UPDATE Users SET LastName = ‘Michel’ WHERE LastName = ‘Thomas’
Option D – UPDATE Users SET LastName = ‘Michel’ WHERE LastName = ‘Thomas’
Q16.Which type of JOIN is used to returns rows that do not have matching values?
A. Natural JOIN
B. Outer JOIN
C. EQUI JOIN
D. All of the above
Option B – Outer JOIN
Q17.A CASE SQL statement is __?
A. A way to establish a loop in SQL.
B. A way to establish an IF-THEN-ELSE in SQL
C. A way to establish a data definition in SQL
D. All of the above.
Option B – A way to establish an IF-THEN-ELSE in SQL
Q18.Which statement is true regarding procedures?
A. They include procedural and SQL statements.
B. They work similarly to the functions.
C. It does not need unique names.
D. It cannot be created with SQL statements.
Option A – They include procedural and SQL statements.
Q19.Group of operations that form a single logical unit of work is known as
A. View
B. Network
C. Unit
D. Transaction
Option D – Transaction
Q20.Shared locks are applied while performing
A. Read operations
B. Write operations
C. A & B both
D. None of the above
Option A – Read operations
Q21.A sequence in SQL can generate a maximum number:
A. 39 digits
B. 38 digits
C. 40 digits
D. 37 digits
Option B – 38 digits
Q22.What is the difference between a PRIMARY KEY and a UNIQUE KEY?
A. Primary key can store null value, whereas a unique key cannot store null value.
B. We can have only one primary key in a table while we can have multiple unique keys
C. Primary key cannot be a date variable whereas unique key can be
D. None of these
Option B – We can have only one primary key in a table while we can have multiple unique keys
Q23.Which operator is used to compare the NULL values in SQL?
A. Equal
B. IN
C. IS
D.None of Above
Option C – Is
Q24.__ is NOT a type of constraint in SQL language?
A. FOREIGN KEY
B. PRIMARY KEY
C. UNIQUE
D. ALTERNATE KEY
Option D – ALTERNATE KEY
Q25.Which statement is used to get all data from the student table whose name starts with p?
A. SELECT * FROM student WHERE name LIKE ‘%p%’;
B. SELECT * FROM student WHERE name LIKE ‘p%’;
C. SELECT * FROM student WHERE name LIKE ‘_p%’;
D. SELECT * FROM student WHERE name LIKE ‘%p’;
Option B – SELECT * FROM student WHERE name LIKE ‘p%’;