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Update uk-price-paid.md

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Denny Crane 2021-08-09 11:17:35 -03:00 committed by GitHub
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docs/en/getting-started/example-datasets/uk-price-paid.md
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@ -324,12 +324,12 @@ The data is uploaded to ClickHouse Playground, [example](https://gh-api.clickhou
## Let's speed up queries using projections
[Projections](https://../../sql-reference/statements/alter/projection/) allows to improve queries speed by storing pre-aggregated data
[Projections](https://../../sql-reference/statements/alter/projection/) allow to improve queries speed by storing pre-aggregated data.
### Bultd a projection
### Build a projection
```
-- create an aggregating projection by dimensions (toYear(date), district, town)
-- create an aggregate projection by dimensions (toYear(date), district, town)
ALTER TABLE uk_price_paid
ADD PROJECTION projection_by_year_district_town
@ -355,7 +355,7 @@ ALTER TABLE uk_price_paid
SETTINGS mutations_sync = 1;
```
## Test performarnce
## Test performance
Let's run the same 3 queries.