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Diffstat (limited to 'doc/development/database/clickhouse/gitlab_activity_data.md')
-rw-r--r--doc/development/database/clickhouse/gitlab_activity_data.md6
1 files changed, 3 insertions, 3 deletions
diff --git a/doc/development/database/clickhouse/gitlab_activity_data.md b/doc/development/database/clickhouse/gitlab_activity_data.md
index 6ba11b8afaf..7c30703a016 100644
--- a/doc/development/database/clickhouse/gitlab_activity_data.md
+++ b/doc/development/database/clickhouse/gitlab_activity_data.md
@@ -246,9 +246,9 @@ ORDER BY id;
A few changes compared to the PostgreSQL version:
-- `target_type` uses [an optimization](https://clickhouse.com/docs/en/sql-reference/data-types/lowcardinality/) for low-cardinality column values.
+- `target_type` uses [an optimization](https://clickhouse.com/docs/en/sql-reference/data-types/lowcardinality) for low-cardinality column values.
- `fingerprint` becomes an integer and leverages a performant integer-based hashing function such as xxHash64.
-- All columns get a default value, the 0 default value for the integer columns means no value. See the related [best practices](https://clickhouse.com/docs/en/cloud/bestpractices/avoid-nullable-columns/).
+- All columns get a default value, the 0 default value for the integer columns means no value. See the related [best practices](https://clickhouse.com/docs/en/cloud/bestpractices/avoid-nullable-columns).
- `NOT NULL` to ensure that we always use the default values when data is missing (different behavior compared to PostgreSQL).
- The "primary" key automatically becomes the `id` column due to the `ORDER BY` clause.
@@ -276,7 +276,7 @@ ClickHouse will eventually "replace" the rows with the same primary key in the b
SELECT * FROM events FINAL
```
-Adding `FINAL` to a query can have significant performance consequences, some of the issues are documented in the [ClickHouse documentation](https://clickhouse.com/docs/en/sql-reference/statements/select/from/#final-modifier).
+Adding `FINAL` to a query can have significant performance consequences, some of the issues are documented in the [ClickHouse documentation](https://clickhouse.com/docs/en/sql-reference/statements/select/from#final-modifier).
We should always expect duplicated values in the table, so we must take care of the deduplication in query time.