Quiz on Python and SQL Database Integration

What command is used to install the MySQL connector library in Python?

• mysql.connector install

• install mysql.connector

• pip install mysql

• pip install mysql.connector

Answer explanation

The correct command to install the MySQL connector library in Python is 'pip install mysql.connector'. This command uses pip, the package installer for Python, to fetch and install the mysql.connector package.

What is the purpose of the cursor object in database operations?

• To connect to the database

• To manage user sessions

• To execute SQL queries

• To store database credentials

Answer explanation

The cursor object is essential for executing SQL queries in a database. It allows interaction with the database by sending commands and retrieving results, making it a key component in database operations.

Which method retrieves all records from the result set?

• fetchmany(n)

• getall()

• fetchall()

• fetchone()

Answer explanation

The method fetchall() retrieves all records from the result set at once, making it the correct choice. In contrast, fetchone() retrieves a single record, and fetchmany(n) retrieves a specified number of records.

What SQL command is used to create a new table?

• CREATE TABLE

• NEW TABLE

• ADD TABLE

• TABLE CREATE

Answer explanation

The correct SQL command to create a new table is 'CREATE TABLE'. This command is standard in SQL for defining a new table structure in a database.

Which method is used to commit changes to the database?

• apply()

• save()

• commit()

• mydb.commit()

Answer explanation

The correct method to commit changes to the database is 'mydb.commit()'. This method finalizes the transaction, ensuring that all changes made during the session are saved to the database.

What is the correct way to execute a SELECT query?

• c.execute('SELECT * FROM table')

• c.run('SELECT * FROM table')

• c.query('SELECT * FROM table')

• c.fetch('SELECT * FROM table')

Answer explanation

The correct way to execute a SELECT query in SQL is using the 'execute' method. Therefore, 'c.execute('SELECT * FROM table')' is the right choice, while the other options do not represent valid methods for executing SQL queries.

How do you update a record in a table?

• UPDATE table SET column=value WHERE condition

• MODIFY table SET column=value WHERE condition

• CHANGE table SET column=value WHERE condition

• ALTER table SET column=value WHERE condition

Answer explanation

To update a record in a table, you use the SQL command 'UPDATE table SET column=value WHERE condition'. This syntax specifies which table to modify, which column to change, and the condition to identify the record.

What is the purpose of the 'DESC' command?

• To describe the structure of a table

• To create a new table

• To display all records

• To delete a table

Answer explanation

The 'DESC' command is used in SQL to describe the structure of a table, including its columns and data types. This makes it the correct choice, as it provides essential information about the table's design.

Which method is used to delete a record from a table?

• DROP FROM table WHERE condition

• REMOVE FROM table WHERE condition

• DELETE FROM table WHERE condition

• ERASE FROM table WHERE condition

Answer explanation

The correct method to delete a record from a table in SQL is 'DELETE FROM table WHERE condition'. The other options, such as 'DROP', 'REMOVE', and 'ERASE', are not valid SQL commands for this operation.

What does the 'rowcount' property of the cursor object return?

• Number of rows affected by the last operation

• Number of active connections

• Number of columns in the table

• Total number of rows in the table

Answer explanation

The 'rowcount' property of the cursor object returns the number of rows affected by the last operation executed. This is useful for understanding the impact of commands like INSERT, UPDATE, or DELETE.