POC Data Management & Integration 2

Question 1

Which pandas method is used to merge two DataFrames on a common column, similar to a SQL JOIN?

Accepted Answer

merge()

Answer

pd.merge() combines DataFrames based on one or more shared key columns, mirroring SQL JOIN behavior.

Question 2

When reading a CSV file with pandas, which parameter specifies a custom delimiter instead of a comma?

Accepted Answer

sep

Answer

The 'sep' parameter in pd.read_csv() defines the character used to separate fields in the file.

Question 3

Which Python library provides the 'connect()' function used to establish a connection to a SQLite database?

Accepted Answer

sqlite3

Answer

The built-in sqlite3 module's connect() function creates or opens a SQLite database file.

Question 4

What does the pandas 'fillna()' method do?

Accepted Answer

Replaces NaN values with a specified value

Answer

fillna() replaces missing (NaN) values in a DataFrame or Series with a given scalar, dict, or method.

Question 5

In Python's sqlite3 module, what object is used to execute SQL statements?

Accepted Answer

Cursor

Answer

A Cursor object obtained via connection.cursor() is used to execute SQL commands and fetch results.

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