Cross-Border Calling Share

SQL practice question · Medium · Aggregation · Verizon

voice_sessions has one row per call (user_id, call_id, is_international) where is_international is 1 for an international call and 0 otherwise. For each user, compute the percentage of their calls that were international. Output columns: user_id, international_pct (rounded to 2 decimals). Order by user_id ascending.

Table: voice_sessions

Schema of voice_sessions
Column	Type
user_id	INTEGER
call_id	INTEGER
is_international	BOOLEAN

Schema of voice_sessions

Column

Type

user_id

INTEGER

call_id

INTEGER

is_international

BOOLEAN

Sample rows of voice_sessions
user_id	call_id	is_international
1	1	1
1	2	0
1	3	1
2	4	0
2	5	0
3	6	1

Sample rows of voice_sessions

user_id

call_id

is_international

Expected output on the sample data
user_id	international_pct
1	66.67
2	0
3	100

Expected output on the sample data

user_id

international_pct

66.67

100

Solve it in the live editor on this page — run on sample data, then submit against hidden tests.

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