First Purchase Amount Bucket | Dataford Interview Questions

Write a SQL query to find the most common first transaction amount bucket.

Use each account's earliest posted transaction, excluding transactions with a NULL amount. Define buckets as < \$50, \$50-\$99.99, \$100-\$199.99, and \$200+. If multiple transactions share a timestamp, use the lower transaction ID as the earlier transaction.

Output

Return one row with amount_bucket and account_count.
Include the bucket containing the largest number of accounts. Break ties by the lower bucket range.

Schema

accounts

Column	Type	Description
account_idPK	INT	Unique account identifier
created_date	DATE	Date the account was created

transactions

Column	Type	Description
transaction_idPK	INT	Unique transaction identifier
account_id	INT	Account associated with the transaction
occurred_at	TIMESTAMP	Timestamp when the transaction occurred
amount	DECIMAL(10,2)	Transaction amount
status	VARCHAR(20)	Transaction processing status

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