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create table startups(category varchar, valuation integer);
insert into startups(category, valuation) values
('a', 10), ('a', 16), ('a', 8),
('b', 1), ('b', 2), ('b', 100), ('b', 1);
SELECT category, valuation
FROM startups
group by 1;
| category | valuation |
|---|---|
| a | 10 |
| b | 1 |
SELECT category, avg(valuation)
FROM startups
group by 1;
| category | avg(valuation) |
|---|---|
| a | 11.333333333333334 |
| b | 26 |