Querying Null Entries | Dataford Interview Questions

First Trust Capital Management is reviewing client account data before producing advisor and regulatory reports. Write a PostgreSQL query that returns every account with one or more missing required values or without a matching advisor record.

Requirements

Use a LEFT JOIN so accounts are retained even when their advisor is missing.
Identify rows where risk_profile or tax_status is NULL, or where the account has no matching advisor.
Return the account ID, client name, advisor name, and a comma-separated description of the missing entries.
Sort the results by account_id ascending.

Schema

client_accounts

Column	Type	Description
account_idPK	INT	Unique client account identifier
client_name	VARCHAR(100)	Client or household name
advisor_id	INT	Assigned advisor identifier
risk_profile	VARCHAR(30)	Investment risk classification
tax_status	VARCHAR(30)	Tax treatment of the account
opened_on	DATE	Account opening date

advisors

Column	Type	Description
advisor_idPK	INT	Unique advisor identifier
advisor_name	VARCHAR(100)	Advisor's full name
team_name	VARCHAR(80)	Advisor team

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