Learn MYSQL MCQs
Prepare MYSQL MCQs (Multiple choice Questions) for exam and job interviews.
How do you set a default value for a column in MySQL?
1) ALTER TABLE table_name ALTER column_name SET DEFAULT value;
2) CREATE TABLE table_name (column_name data_type DEFAULT value);
3) SET DEFAULT column_name=value;
4) ALTER TABLE table_name CHANGE column_name column_name data_type DEFAULT value;
Answer : Option 2
Which function is used to convert a string to an integer in MySQL?
1) CONVERT()
2) CAST()
3) TO_NUMBER()
4) INT()
Answer : Option 2
What does the SQL SHOW DATABASES command do?
1) Displays all databases on the MySQL server
2) Creates a new database
3) Deletes a database
4) Updates a database
Answer : Option 1
How do you add a comment to your SQL code?
1) -- This is a comment
2) # This is a comment
3) /* This is a comment */
4) All of the above
Answer : Option 4
What does the SQL CHAR_LENGTH() function return?
1) The number of characters in a string
2) The number of bytes used by a string
3) The number of words in a string
4) The maximum length of a string
Answer : Option 1
Which command is used to lock a table in MySQL?
1) LOCK TABLE table_name;
2) TABLE LOCK table_name;
3) SET LOCK table_name;
4) ALTER TABLE table_name LOCK;
Answer : Option 1
How do you retrieve the current date and time in MySQL?
1) SELECT NOW();
2) SELECT CURRENT_DATE_TIME();
3) SELECT GET_DATE();
4) SELECT TIME();
Answer : Option 1
What is a temporary table in MySQL?
1) A table that exists temporarily during a session
2) A table that is permanently deleted
3) A backup table
4) An index table
Answer : Option 1
How do you prevent SQL injection in MySQL?
1) Use prepared statements
2) Use regular expressions
3) Escape all inputs
4) All of the above
Answer : Option 4
Which command is used to unlock a table in MySQL?
1) UNLOCK TABLE table_name;
2) TABLE UNLOCK table_name;
3) SET UNLOCK table_name;
4) ALTER TABLE table_name UNLOCK;
Answer : Option 1