runtime
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task LEFT JOIN · easy

Predict: members with and without bookings

Predict every member id and matched fee. Members without bookings must remain in the LEFT JOIN result.

what to return

Columns
idfee in this order
Rows
5 rows · in the order asked
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: Keep unmatched rows →

expected result

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

expected result5 rows · in this order
idfee
120
130
2NULL

first 3 of 5 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

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