SQL Joins and Data Structures | Dataford Interview Questions

Tell me about how you use SQL joins and how you choose between lists and tuples in Python when transforming data.

Using the provided Comcast service tables, write a query for active subscriptions and briefly explain the Python collection choice for transforming its result rows.

Output

One row per active subscription, including subscriptions without a matching plan.
Columns: account_id, account_name, subscription_id, plan_name, status, and monthly_charge.
Sort by account_id, then subscription_id ascending.

Schema

accounts

Column	Type	Description
account_idPK	INT	Unique Comcast account identifier
account_name	VARCHAR(100)	Account holder name

subscriptions

Column	Type	Description
subscription_idPK	INT	Unique subscription identifier
account_id	INT	Owning account identifier
plan_id	INT	Referenced service plan identifier
status	VARCHAR(20)	Current subscription status
monthly_charge	NUMERIC(8,2)	Monthly recurring charge

plans

Column	Type	Description
plan_idPK	INT	Unique service plan identifier
plan_name	VARCHAR(100)	Service plan name

Your question is SQL Joins and Data Structures. Start with the requirements and the three tables in the Question tab.

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Problem