Easy challenge 2 of 56: customers joining in a half-open date range
easyD4
customers joining in a half-open date range. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Challenge Library
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18 easy26 medium12 hard
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Confidence prompts, hidden variants, and timer-neutral attempts stay in the normal SQL workspace.
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Easy challenge 1 of 56: stable top products under tied prices
stable top products under tied prices. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
easyD4
More challenges
Showing 9 of 56.
Easy challenge 3 of 56: normalize and match messy city values
easyD4
normalize and match messy city values. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 4 of 56: count known versus all return dates
easyD4
count known versus all return dates. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 5 of 56: conditional status labels with exact boundaries
easyD4
conditional status labels with exact boundaries. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 6 of 56: grouped order counts by channel
easyD4
grouped order counts by channel. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 7 of 56: groups above a threshold using HAVING
easyD4
groups above a threshold using HAVING. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 8 of 56: customers with at least one completed order
easyD4
customers with at least one completed order. Detect independent one-to-many fan-out and pre-aggregate to a common grain.
Easy challenge 9 of 56: products with no sales
easyD5
products with no sales. Detect independent one-to-many fan-out and pre-aggregate to a common grain.