Database Connectivity With Python MCQs with Explanations

Database connectivity refers to establishing a connection between Python and databases to perform operations.

The sqlite3 module is widely used for database connectivity in Python, especially for SQLite databases.

SQLite is a lightweight, self-contained, serverless, and file-based relational database management system.

New SQLite databases are created by executing SQL queries to define tables and data structures.

A cursor is an object that allows you to interact with a database by executing SQL commands and fetching results.

The connect() function is used to establish a connection to an SQLite database.

The execute() method is used to execute SQL queries on an SQLite database.

SQL injection is a security vulnerability where malicious code is inserted into SQL statements.

Parameterized queries separate user input from SQL code, reducing the risk of SQL injection.

MongoDB is a NoSQL database management system, while the others are relational databases.

Data from a result set is typically fetched by iterating through the result set using loops.

The commit() method saves the changes made during a database transaction.

ORM is a technique that maps database tables to object-oriented programming classes, simplifying database interactions.

SQLAlchemy is a widely used ORM library for Python, supporting various database management systems.

In SQLAlchemy, you inherit from the Base class and define attributes to map a class to a database table.

A primary key is a unique identifier for each row in a database table.

A foreign key is used to establish relationships between tables, ensuring data integrity and referential integrity.

The UPDATE statement is used to modify data in a database table.

A stored procedure is a precompiled collection of SQL statements that can be reused and executed in a database.

You can execute a stored procedure using the execute() method from the sqlite3 module.

Database transactions ensure data integrity, consistency, and the ACID properties (Atomicity, Consistency, Isolation, Durability).

"DATA UNCHANGED" is not an isolation level; the correct option is typically "SERIALIZABLE".

The rollback() method is used to undo changes made during a transaction in the sqlite3 module.

Database normalization organizes data to eliminate redundancy, improve data integrity, and minimize anomalies.

Create, Read, Update, Delete is the correct answer to “What does the term "CRUD" stand for in the context of databases”. This question is standard in competitive examination syllabi for Database Connectivity With Python.