Extract Domain From Emails | Dataford Interview Questions

Write a SQL query to extract the domain name from a column containing raw email addresses.

Use the email_records table and handle leading or trailing whitespace, mixed-case addresses, NULL values, and malformed entries.

Output

One row per valid email record, with columns id, raw_email, and domain_name.
Exclude NULL, blank, and malformed email values.
Normalize domains to lowercase and order results by id ascending.

email_records

Column	Type	Description
idPK	INT	Unique email record identifier
raw_email	VARCHAR(255)	Raw email address, which may contain whitespace, mixed case, or invalid values

Your question is Extract Domain From Emails. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Write a SQL query to extract the domain name from a column containing raw email addresses.

Use the email_records table and handle leading or trailing whitespace, mixed-case addresses, NULL values, and malformed entries.

One row per valid email record, with columns id, raw_email, and domain_name.
Exclude NULL, blank, and malformed email values.
Normalize domains to lowercase and order results by id ascending.

email_records

Column	Type	Description
idPK	INT	Unique email record identifier
raw_email	VARCHAR(255)	Raw email address, which may contain whitespace, mixed case, or invalid values

Your question is Extract Domain From Emails. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.