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PyMySQL interview questions

Prepare for PyMySQL interviews on Skill Zuno. This practice book covers PyMySQL interview questions across New, Easy, Medium, Hard, and Diff levels so you can work through real interview-style problems on skillzunos.com.

Open PyMySQL on Skill Zuno

Also see the PyMySQL tutorial.

PyMySQL is a pure-Python MySQL client that implements the Python DB-API 2.0 (PEP 249). It has no C dependencies, so it installs anywhere pip runs, and it is the driver SQLAlchemy uses for mysql+pymysql:// URLs. PyMySQL interviews focus on connections and cursors, parameterized queries, transactions and error handling.

Sample PyMySQL interview questions

How do you prevent SQL injection with PyMySQL?

Pass values separately from the SQL: cursor.execute("SELECT * FROM users WHERE id = %s", (user_id,)). PyMySQL escapes each value. Never build the query with f-strings or string formatting.

What is the difference between Cursor, DictCursor and SSCursor?

Cursor returns each row as a tuple and DictCursor returns a dict keyed by column name; both load the whole result into memory. SSCursor is unbuffered: it streams rows from the server, which suits very large result sets.

Is autocommit on by default in PyMySQL?

No. Following DB-API, autocommit is off, so changes from INSERT, UPDATE and DELETE are lost unless you call connection.commit(). Pass autocommit=True to connect() to change that.

How do you insert many rows efficiently?

Use cursor.executemany() with a list of tuples. For INSERT … VALUES statements PyMySQL combines the rows into multi-row INSERTs instead of sending one statement per row.

How is PyMySQL different from mysqlclient (MySQLdb)?

PyMySQL is pure Python and easy to install. mysqlclient wraps the C library libmysqlclient: it is faster, but needs a compiler and MySQL headers to build.

What you can practice

PyMySQL interview questions for beginners and experienced developers
Level-based practice: New, Easy, Medium, Hard, and Diff
Python Data Science topics alongside PyMySQL on skillzunos.com