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Merge pull request #63099 from HowePa/docs_settings_link

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[Docs] Fixed some settings links
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Konstantin Bogdanov 2024-04-29 12:18:05 +00:00 committed by GitHub
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6
docs/en/engines/table-engines/mergetree-family/mergetree.md
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@ -287,9 +287,9 @@ The number of columns in the primary key is not explicitly limited. Depending on
A long primary key will negatively affect the insert performance and memory consumption, but extra columns in the primary key do not affect ClickHouse performance during `SELECT` queries.
You can create a table without a primary key using the `ORDER BY tuple()` syntax. In this case, ClickHouse stores data in the order of inserting. If you want to save data order when inserting data by `INSERT ... SELECT` queries, set [max_insert_threads = 1](/docs/en/operations/settings/settings.md/#settings-max-insert-threads).
You can create a table without a primary key using the `ORDER BY tuple()` syntax. In this case, ClickHouse stores data in the order of inserting. If you want to save data order when inserting data by `INSERT ... SELECT` queries, set [max_insert_threads = 1](/docs/en/operations/settings/settings.md/#max-insert-threads).
To select data in the initial order, use [single-threaded](/docs/en/operations/settings/settings.md/#settings-max_threads) `SELECT` queries.
To select data in the initial order, use [single-threaded](/docs/en/operations/settings/settings.md/#max_threads) `SELECT` queries.
### Choosing a Primary Key that Differs from the Sorting Key {#choosing-a-primary-key-that-differs-from-the-sorting-key}
@ -344,7 +344,7 @@ In the example below, the index can’t be used.
SELECT count() FROM table WHERE CounterID = 34 OR URL LIKE '%upyachka%'
```
To check whether ClickHouse can use the index when running a query, use the settings [force_index_by_date](/docs/en/operations/settings/settings.md/#settings-force_index_by_date) and [force_primary_key](/docs/en/operations/settings/settings.md/#force-primary-key).
To check whether ClickHouse can use the index when running a query, use the settings [force_index_by_date](/docs/en/operations/settings/settings.md/#force_index_by_date) and [force_primary_key](/docs/en/operations/settings/settings.md/#force-primary-key).
The key for partitioning by month allows reading only those data blocks which contain dates from the proper range. In this case, the data block may contain data for many dates (up to an entire month). Within a block, data is sorted by primary key, which might not contain the date as the first column. Because of this, using a query with only a date condition that does not specify the primary key prefix will cause more data to be read than for a single date.

2
docs/en/engines/table-engines/mergetree-family/replication.md
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@ -113,7 +113,7 @@ You can specify any existing ZooKeeper cluster and the system will use a directo
If ZooKeeper is not set in the config file, you can’t create replicated tables, and any existing replicated tables will be read-only.
ZooKeeper is not used in `SELECT` queries because replication does not affect the performance of `SELECT` and queries run just as fast as they do for non-replicated tables. When querying distributed replicated tables, ClickHouse behavior is controlled by the settings [max_replica_delay_for_distributed_queries](/docs/en/operations/settings/settings.md/#settings-max_replica_delay_for_distributed_queries) and [fallback_to_stale_replicas_for_distributed_queries](/docs/en/operations/settings/settings.md/#settings-fallback_to_stale_replicas_for_distributed_queries).
ZooKeeper is not used in `SELECT` queries because replication does not affect the performance of `SELECT` and queries run just as fast as they do for non-replicated tables. When querying distributed replicated tables, ClickHouse behavior is controlled by the settings [max_replica_delay_for_distributed_queries](/docs/en/operations/settings/settings.md/#max_replica_delay_for_distributed_queries) and [fallback_to_stale_replicas_for_distributed_queries](/docs/en/operations/settings/settings.md/#fallback_to_stale_replicas_for_distributed_queries).
For each `INSERT` query, approximately ten entries are added to ZooKeeper through several transactions. (To be more precise, this is for each inserted block of data; an INSERT query contains one block or one block per `max_insert_block_size = 1048576` rows.) This leads to slightly longer latencies for `INSERT` compared to non-replicated tables. But if you follow the recommendations to insert data in batches of no more than one `INSERT` per second, it does not create any problems. The entire ClickHouse cluster used for coordinating one ZooKeeper cluster has a total of several hundred `INSERTs` per second. The throughput on data inserts (the number of rows per second) is just as high as for non-replicated data.

2
docs/en/engines/table-engines/special/join.md
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@ -83,7 +83,7 @@ When creating a table, the following settings are applied:
#### join_any_take_last_row
[join_any_take_last_row](/docs/en/operations/settings/settings.md/#settings-join_any_take_last_row)
[join_any_take_last_row](/docs/en/operations/settings/settings.md/#join_any_take_last_row)
#### join_use_nulls
#### persistent