Learn MYSQL MCQs
Prepare MYSQL MCQs (Multiple choice Questions) for exam and job interviews.
Which command is used to change a user’s password in MySQL?
1) ALTER USER user_name IDENTIFIED BY "new_password";
2) UPDATE USER user_name SET PASSWORD="new_password";
3) CHANGE USER user_name TO "new_password";
4) MODIFY USER user_name PASSWORD="new_password";
Answer : Option 1
How do you create a composite primary key in MySQL?
1) CREATE TABLE table_name (column1 data_type, column2 data_type, PRIMARY KEY (column1, column2));
2) ALTER TABLE table_name ADD PRIMARY KEY (column1, column2);
3) SET PRIMARY KEY (column1, column2) ON table_name;
4) CREATE TABLE table_name (column1 data_type, column2 data_type, UNIQUE (column1, column2));
Answer : Option 1
What does the SQL IFNULL() function do?
1) Returns the first argument if it is not NULL, otherwise returns the second argument
2) Checks if a value is NULL
3) Converts NULL to 0
4) Replaces NULL values with empty strings
Answer : Option 1
Which command is used to set a variable in MySQL?
1) SET @variable_name = value;
2) DEFINE variable_name = value;
3) DECLARE variable_name = value;
4) CREATE variable_name = value;
Answer : Option 1
What is the purpose of the SQL TRIM() function?
1) Removes whitespace from both sides of a string
2) Finds the length of a string
3) Converts a string to uppercase
4) Concatenates strings
Answer : Option 1
Which function is used to convert a string to lowercase in MySQL?
1) LOWER()
2) LOW()
3) TO_LOWER()
4) LCASE()
Answer : Option 1
How do you find records with NULL values in a column?
1) SELECT * FROM table_name WHERE column_name IS NULL;
2) SELECT * FROM table_name WHERE column_name = NULL;
3) SELECT * FROM table_name WHERE column_name IS EMPTY;
4) SELECT * FROM table_name WHERE column_name NOT PRESENT;
Answer : Option 1
Which command is used to modify an existing column in MySQL?
1) ALTER TABLE table_name MODIFY column_name data_type;
2) CHANGE TABLE table_name CHANGE column_name data_type;
3) UPDATE TABLE table_name SET column_name = data_type;
4) MODIFY TABLE table_name ALTER column_name data_type;
Answer : Option 1
What does the SQL DATE_ADD() function do?
1) Adds a time interval to a date
2) Subtracts a time interval from a date
3) Formats a date
4) Extracts the year from a date
Answer : Option 1
Which SQL command is used to remove a database?
1) DROP DATABASE database_name;
2) DELETE DATABASE database_name;
3) REMOVE DATABASE database_name;
4) CLEAR DATABASE database_name;
Answer : Option 1