What is the purpose of the COALESCE function?

To join string columns together.

To return the first non-null value from a list of arguments.

To count total non-null values inside a group.

To drop null columns from the schema.

easy #sql #postgresql #retail

QUESTION 01 OF 02

Handling NULL values

Quiz for lesson: Handling NULL values

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What does the expression NULL = NULL evaluate to?

About this Quiz

This interactive assessment is designed to test your understanding of Handling NULL values. Whether you are a beginner looking to grasp the basics or an experienced professional aiming to refine your skills, quizzes are an excellent way to validate your knowledge and identify areas for improvement.

Instructions

Read each question carefully before answering.
Some questions may have multiple correct answers.
There is no time limit, so take your time to think.
You will receive immediate feedback after submission.

Learning Outcomes

Self-assess your current skill level.
Reinforce key concepts through active recall.
Identify knowledge gaps to focus your study.
Gain confidence in your technical expertise.
Reinforce memory and recall.