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FX Fee Take Rate by Currency

HardProQuerying BasicsJoinsAggregation & Grouping

FX is where a multi-currency neobank earns its margin, and a take rate is read in basis points. Exchanges are transactions with type = 'fx_exchange'; the currency column holds the currency bought, and currencies names it. Use completed exchanges only.

Return code, name, exchanges (row count), volume_gbp (SUM of amount_gbp), fees_gbp (SUM of fee_gbp) — both rounded to 2 decimals — and fee_bps (10000.0 * fees / volume, rounded to 1 decimal). One row per currency. Order by fees_gbp descending.

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Schema

transactions

txn_id	user_id	ts	type	amount	currency	amount_gbp	fee_gbp	merchant_category	merchant_country	counterparty_user_id	status	decline_reason
1	1	2025-06-14 11:01:51	fx_exchange	32271.15	JPY	167.81	1.68	NULL	NULL	NULL	completed	NULL
2	1	2025-06-14 11:17:45	bill_payment	59.53	EUR	50.6	0	utilities	IE	NULL	completed	NULL
3	7	2025-06-16 10:06:38	card_payment	122.27	EUR	103.93	0	shopping	ES	NULL	completed	NULL

currencies

code	name	rate_to_gbp
GBP	Pound sterling	1
EUR	Euro	0.85
USD	US dollar	0.78

Expected output: code=PLN, name=Polish złoty, exchanges=17, volume_gbp=6482.97, fees_gbp=22.42, fee_bps=34.6 ...

Hint

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Concepts

SELECT JOIN GROUP BY SUM COUNT JOIN + Aggregation

Practise the topic: SQL practice questions · JOIN practice · GROUP BY exercises · Advanced SQL interview questions

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FX Fee Take Rate by Currency

Schema

Hint

Concepts

In these company practice sets

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