[Solved] A dbt test is written as: select * from {{ ref('orders') }} where customer_email not like '%@%' But it returns no rows even though some emails are invalid. What is the most probable reason? | dbt

dbt - Advanced Testing

A dbt test is written as:

select * from {{ ref('orders') }} where customer_email not like '%@%'

But it returns no rows even though some emails are invalid. What is the most probable reason?

AThe invalid emails contain NULL values which are not matched by LIKE

BThe test syntax is incorrect and causes no results

CAll emails actually contain '@' so test is correct

DThe table reference {{ ref('orders') }} is incorrect

Step-by-Step Solution

Solution:

Step 1: Understand LIKE behavior
LIKE does not match NULL values; NULLs are excluded.
Step 2: Identify issue
Invalid emails might be NULL, so test returns no rows.
Final Answer:
The invalid emails contain NULL values which are not matched by LIKE -> Option A
Quick Check:
LIKE ignores NULLs, causing false negatives [OK]

Quick Trick: LIKE does not match NULL values [OK]

Common Mistakes:

MISTAKES

Master "Advanced Testing" in dbt

9 interactive learning modes - each teaches the same concept differently

More dbt Quizzes

A dbt test is written as: