runtime
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task GROUP BY · medium

Predict: count rows or known values?

Predict one summary per team. Count every member separately from members whose credits are known.

what to return

Columns
teammembersknown_credits in this order
Rows
2 rows · any order
Watch for
Use the sample data shown here. NULL is not zero or empty text. Keep duplicate result rows.
Skill
Reason about the exact result of a fixed SQL query. Refresher: Group into summaries →

expected result

Your query should return exactly these columns and values. Run it and compare.

expected result2 rows · any order
teammembersknown_credits
Blue21
Red22

all 2 rows

data you can query

Sample rows from each table. Each column shows its type underneath; → marks a link to another table.

studio_members4 columns · 4 rows
idinteger · keynametextteamtextcreditsinteger
1LuzRed80
2KitRed80
3RemyBlue50
4SolBlueNULL

all 4 rows

studio_bookings4 columns · 4 rows
idinteger · keymember_idinteger → studio_membersfeeintegerbooked_attext
111202026-04-01
121302026-04-30
132NULL2026-05-01
14NULL202026-04-15

all 4 rows

This question asks you to predict an output. The prototype covers write and debug questions; open it in the current app.

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