[docs] split the ALTER article (#12502)

* initial split

* initial adjust links

* make en buildable

* re-normalize

docs/en/engines/table-engines/integrations/rabbitmq.md

@@ -2,11 +2,13 @@
 toc_priority: 6
 toc_title: RabbitMQ
 ---
-# RabbitMQ Engine
+
+# RabbitMQ Engine {#rabbitmq-engine}
 
 This engine allows integrating ClickHouse with [RabbitMQ](https://www.rabbitmq.com).
 
 RabbitMQ lets you:
+
 -   Publish or subscribe to data flows.
 -   Process streams as they become available.
 
@@ -43,7 +45,7 @@ Optional parameters:
 -   `rabbitmq_row_delimiter` – Delimiter character, which ends the message.
 -   `rabbitmq_num_consumers` – The number of consumers per table. Default: `1`. Specify more consumers if the throughput of one consumer is insufficient.
 -   `rabbitmq_num_queues` – The number of queues per consumer. Default: `1`. Specify more queues if the capacity of one queue per consumer is insufficient. Single queue can contain up to 50K messages at the same time.
--   `rabbitmq_transactional_channel` –  Wrap insert queries in transactions. Default: `0`.
+-   `rabbitmq_transactional_channel` – Wrap insert queries in transactions. Default: `0`.
 
 Required configuration:
 
@@ -83,6 +85,7 @@ Data can be channeled based on `rabbitmq_exchange_type` and the specified `rabbi
 There can be no more than one exchange per table. One exchange can be shared between multiple tables - it enables routing into multiple tables at the same time.
 
 Exchange type options:
+
 -   `direct` - Routing is based on exact matching of keys. Example table key list: `key1,key2,key3,key4,key5`, message key can eqaul any of them.
 -   `fanout` - Routing to all tables (where exchange name is the same) regardless of the keys.
 -   `topic` - Routing is based on patterns with dot-separated keys. Examples: `*.logs`, `records.*.*.2020`, `*.2018,*.2019,*.2020`.
@@ -92,6 +95,7 @@ Exchange type options:
 If exchange type is not specified, then default is `fanout` and routing keys for data publishing must be randomized in range `[1, num_consumers]` for every message/batch (or in range `[1, num_consumers * num_queues]` if `rabbitmq_num_queues` is set). This table configuration works quicker then any other, especially when `rabbitmq_num_consumers` and/or `rabbitmq_num_queues` parameters are set.
 
 If `rabbitmq_num_consumers` and/or `rabbitmq_num_queues` parameters are specified along with `rabbitmq_exchange_type`, then:
+
 -   `rabbitmq-consistent-hash-exchange` plugin must be enabled.
 -   `message_id` property of the published messages must be specified (unique for each message/batch).
 
@@ -116,4 +120,3 @@ Example:
 
   SELECT key, value FROM daily ORDER BY key;
 ```
-

docs/en/engines/table-engines/log-family/index.md

@@ -26,7 +26,7 @@ Engines:
 
     During `INSERT` queries, the table is locked, and other queries for reading and writing data both wait for the table to unlock. If there are no data writing queries, any number of data reading queries can be performed concurrently.
 
--   Do not support [mutation](../../../sql-reference/statements/alter.md#alter-mutations) operations.
+-   Do not support [mutations](../../../sql-reference/statements/alter/index.md#alter-mutations).
 
 -   Do not support indexes.
 

docs/en/engines/table-engines/mergetree-family/custom-partitioning-key.md

@@ -116,10 +116,10 @@ drwxr-xr-x 2 clickhouse clickhouse 4096 Feb  1 16:48 detached
 
 The folders ‘201901\_1\_1\_0’, ‘201901\_1\_7\_1’ and so on are the directories of the parts. Each part relates to a corresponding partition and contains data just for a certain month (the table in this example has partitioning by month).
 
-The `detached` directory contains parts that were detached from the table using the [DETACH](../../../sql-reference/statements/alter.md#alter_detach-partition) query. The corrupted parts are also moved to this directory, instead of being deleted. The server does not use the parts from the `detached` directory. You can add, delete, or modify the data in this directory at any time – the server will not know about this until you run the [ATTACH](../../../sql-reference/statements/alter.md#alter_attach-partition) query.
+The `detached` directory contains parts that were detached from the table using the [DETACH](../../../sql-reference/statements/alter/partition.md#alter_detach-partition) query. The corrupted parts are also moved to this directory, instead of being deleted. The server does not use the parts from the `detached` directory. You can add, delete, or modify the data in this directory at any time – the server will not know about this until you run the [ATTACH](../../../sql-reference/statements/alter/partition.md#alter_attach-partition) query.
 
 Note that on the operating server, you cannot manually change the set of parts or their data on the file system, since the server will not know about it. For non-replicated tables, you can do this when the server is stopped, but it isn’t recommended. For replicated tables, the set of parts cannot be changed in any case.
 
-ClickHouse allows you to perform operations with the partitions: delete them, copy from one table to another, or create a backup. See the list of all operations in the section [Manipulations With Partitions and Parts](../../../sql-reference/statements/alter.md#alter_manipulations-with-partitions).
+ClickHouse allows you to perform operations with the partitions: delete them, copy from one table to another, or create a backup. See the list of all operations in the section [Manipulations With Partitions and Parts](../../../sql-reference/statements/alter/partition.md#alter_manipulations-with-partitions).
 
 [Original article](https://clickhouse.tech/docs/en/operations/table_engines/custom_partitioning_key/) <!--hide-->

docs/en/engines/table-engines/mergetree-family/mergetree.md

@@ -212,7 +212,7 @@ This feature is helpful when using the [SummingMergeTree](../../../engines/table
 
 In this case it makes sense to leave only a few columns in the primary key that will provide efficient range scans and add the remaining dimension columns to the sorting key tuple.
 
-[ALTER](../../../sql-reference/statements/alter.md) of the sorting key is a lightweight operation because when a new column is simultaneously added to the table and to the sorting key, existing data parts don’t need to be changed. Since the old sorting key is a prefix of the new sorting key and there is no data in the newly added column, the data is sorted by both the old and new sorting keys at the moment of table modification.
+[ALTER](../../../sql-reference/statements/alter/index.md) of the sorting key is a lightweight operation because when a new column is simultaneously added to the table and to the sorting key, existing data parts don’t need to be changed. Since the old sorting key is a prefix of the new sorting key and there is no data in the newly added column, the data is sorted by both the old and new sorting keys at the moment of table modification.
 
 ### Use of Indexes and Partitions in Queries {#use-of-indexes-and-partitions-in-queries}
 
@@ -490,7 +490,7 @@ If you perform the `SELECT` query between merges, you may get expired data. To a
 
 `MergeTree` family table engines can store data on multiple block devices. For example, it can be useful when the data of a certain table are implicitly split into “hot” and “cold”. The most recent data is regularly requested but requires only a small amount of space. On the contrary, the fat-tailed historical data is requested rarely. If several disks are available, the “hot” data may be located on fast disks (for example, NVMe SSDs or in memory), while the “cold” data - on relatively slow ones (for example, HDD).
 
-Data part is the minimum movable unit for `MergeTree`-engine tables. The data belonging to one part are stored on one disk. Data parts can be moved between disks in the background (according to user settings) as well as by means of the [ALTER](../../../sql-reference/statements/alter.md#alter_move-partition) queries.
+Data part is the minimum movable unit for `MergeTree`-engine tables. The data belonging to one part are stored on one disk. Data parts can be moved between disks in the background (according to user settings) as well as by means of the [ALTER](../../../sql-reference/statements/alter/partition.md#alter_move-partition) queries.
 
 ### Terms {#terms}
 
@@ -636,9 +636,9 @@ The number of threads performing background moves of data parts can be changed b
 In the case of `MergeTree` tables, data is getting to disk in different ways:
 
 -   As a result of an insert (`INSERT` query).
--   During background merges and [mutations](../../../sql-reference/statements/alter.md#alter-mutations).
+-   During background merges and [mutations](../../../sql-reference/statements/alter/index.md#alter-mutations).
 -   When downloading from another replica.
--   As a result of partition freezing [ALTER TABLE … FREEZE PARTITION](../../../sql-reference/statements/alter.md#alter_freeze-partition).
+-   As a result of partition freezing [ALTER TABLE … FREEZE PARTITION](../../../sql-reference/statements/alter/partition.md#alter_freeze-partition).
 
 In all these cases except for mutations and partition freezing, a part is stored on a volume and a disk according to the given storage policy:
 
@@ -650,7 +650,7 @@ Under the hood, mutations and partition freezing make use of [hard links](https:
 In the background, parts are moved between volumes on the basis of the amount of free space (`move_factor` parameter) according to the order the volumes are declared in the configuration file.
 Data is never transferred from the last one and into the first one. One may use system tables [system.part\_log](../../../operations/system-tables/part_log.md#system_tables-part-log) (field `type = MOVE_PART`) and [system.parts](../../../operations/system-tables/parts.md#system_tables-parts) (fields `path` and `disk`) to monitor background moves. Also, the detailed information can be found in server logs.
 
-User can force moving a part or a partition from one volume to another using the query [ALTER TABLE … MOVE PART\|PARTITION … TO VOLUME\|DISK …](../../../sql-reference/statements/alter.md#alter_move-partition), all the restrictions for background operations are taken into account. The query initiates a move on its own and does not wait for background operations to be completed. User will get an error message if not enough free space is available or if any of the required conditions are not met.
+User can force moving a part or a partition from one volume to another using the query [ALTER TABLE … MOVE PART\|PARTITION … TO VOLUME\|DISK …](../../../sql-reference/statements/alter/partition.md#alter_move-partition), all the restrictions for background operations are taken into account. The query initiates a move on its own and does not wait for background operations to be completed. User will get an error message if not enough free space is available or if any of the required conditions are not met.
 
 Moving data does not interfere with data replication. Therefore, different storage policies can be specified for the same table on different replicas.
 

docs/en/engines/table-engines/mergetree-family/replication.md

@@ -19,7 +19,7 @@ Replication works at the level of an individual table, not the entire server. A
 
 Replication does not depend on sharding. Each shard has its own independent replication.
 
-Compressed data for `INSERT` and `ALTER` queries is replicated (for more information, see the documentation for [ALTER](../../../sql-reference/statements/alter.md#query_language_queries_alter)).
+Compressed data for `INSERT` and `ALTER` queries is replicated (for more information, see the documentation for [ALTER](../../../sql-reference/statements/alter/index.md#query_language_queries_alter)).
 
 `CREATE`, `DROP`, `ATTACH`, `DETACH` and `RENAME` queries are executed on a single server and are not replicated:
 

docs/en/faq/operations/delete-old-data.md

@@ -27,16 +27,16 @@ ClickHouse doesn’t have real-time point deletes like in [OLTP](https://en.wiki
 
 This is the most common approach to make your system based on ClickHouse [GDPR](https://gdpr-info.eu)-compliant.
 
-More details on [mutations](../../sql-reference/statements/alter.md#alter-mutations).
+More details on [mutations](../../sql-reference/statements/alter/index.md#alter-mutations).
 
 ## DROP PARTITION {#drop-partition}
 
 `ALTER TABLE ... DROP PARTITION` provides a cost-efficient way to drop a whole partition. It’s not that flexible and needs proper partitioning scheme configured on table creation, but still covers most common cases. Like mutations need to be executed from an external system for regular use.
 
-More details on [manipulating partitions](../../sql-reference/statements/alter.md#alter_drop-partition).
+More details on [manipulating partitions](../../sql-reference/statements/alter/partition.md#alter_drop-partition).
 
 ## TRUNCATE {#truncate}
 
 It’s rather radical to drop all data from a table, but in some cases it might be exactly what you need.
 
-More details on [table truncation](../../sql-reference/statements/alter.md#alter_drop-partition).
+More details on [table truncation](../../sql-reference/statements/alter/partition.md#alter_drop-partition).

docs/en/operations/access-rights.md

@@ -59,7 +59,7 @@ Privileges can be granted to a user account by the [GRANT](../sql-reference/stat
 Management queries:
 
 -   [CREATE USER](../sql-reference/statements/create/user.md)
--   [ALTER USER](../sql-reference/statements/alter.md#alter-user-statement)
+-   [ALTER USER](../sql-reference/statements/alter/user.md#alter-user-statement)
 -   [DROP USER](../sql-reference/statements/drop.md)
 -   [SHOW CREATE USER](../sql-reference/statements/show.md#show-create-user-statement)
 
@@ -85,7 +85,7 @@ Role contains:
 Management queries:
 
 -   [CREATE ROLE](../sql-reference/statements/create/role.md)
--   [ALTER ROLE](../sql-reference/statements/alter.md#alter-role-statement)
+-   [ALTER ROLE](../sql-reference/statements/alter/role.md#alter-role-statement)
 -   [DROP ROLE](../sql-reference/statements/drop.md)
 -   [SET ROLE](../sql-reference/statements/set-role.md)
 -   [SET DEFAULT ROLE](../sql-reference/statements/set-role.md#set-default-role-statement)
@@ -100,7 +100,7 @@ Row policy is a filter that defines which of the rows are available to a user or
 Management queries:
 
 -   [CREATE ROW POLICY](../sql-reference/statements/create/row-policy.md)
--   [ALTER ROW POLICY](../sql-reference/statements/alter.md#alter-row-policy-statement)
+-   [ALTER ROW POLICY](../sql-reference/statements/alter/row-policy.md#alter-row-policy-statement)
 -   [DROP ROW POLICY](../sql-reference/statements/drop.md#drop-row-policy-statement)
 -   [SHOW CREATE ROW POLICY](../sql-reference/statements/show.md#show-create-row-policy-statement)
 
@@ -111,7 +111,7 @@ Settings profile is a collection of [settings](../operations/settings/index.md).
 Management queries:
 
 -   [CREATE SETTINGS PROFILE](../sql-reference/statements/create/settings-profile.md#create-settings-profile-statement)
--   [ALTER SETTINGS PROFILE](../sql-reference/statements/alter.md#alter-settings-profile-statement)
+-   [ALTER SETTINGS PROFILE](../sql-reference/statements/alter/settings-profile.md#alter-settings-profile-statement)
 -   [DROP SETTINGS PROFILE](../sql-reference/statements/drop.md#drop-settings-profile-statement)
 -   [SHOW CREATE SETTINGS PROFILE](../sql-reference/statements/show.md#show-create-settings-profile-statement)
 
@@ -124,7 +124,7 @@ Quota contains a set of limits for some durations, as well as a list of roles an
 Management queries:
 
 -   [CREATE QUOTA](../sql-reference/statements/create/quota.md)
--   [ALTER QUOTA](../sql-reference/statements/alter.md#alter-quota-statement)
+-   [ALTER QUOTA](../sql-reference/statements/alter/quota.md#alter-quota-statement)
 -   [DROP QUOTA](../sql-reference/statements/drop.md#drop-quota-statement)
 -   [SHOW CREATE QUOTA](../sql-reference/statements/show.md#show-create-quota-statement)
 

docs/en/operations/backup.md

@@ -33,7 +33,7 @@ For smaller volumes of data, a simple `INSERT INTO ... SELECT ...` to remote tab
 ClickHouse allows using the `ALTER TABLE ... FREEZE PARTITION ...` query to create a local copy of table partitions. This is implemented using hardlinks to the `/var/lib/clickhouse/shadow/` folder, so it usually does not consume extra disk space for old data. The created copies of files are not handled by ClickHouse server, so you can just leave them there: you will have a simple backup that doesn’t require any additional external system, but it will still be prone to hardware issues. For this reason, it’s better to remotely copy them to another location and then remove the local copies. Distributed filesystems and object stores are still a good options for this, but normal attached file servers with a large enough capacity might work as well (in this case the transfer will occur via the network filesystem or maybe [rsync](https://en.wikipedia.org/wiki/Rsync)).
 Data can be restored from backup using the `ALTER TABLE ... ATTACH PARTITION ...`
 
-For more information about queries related to partition manipulations, see the [ALTER documentation](../sql-reference/statements/alter.md#alter_manipulations-with-partitions).
+For more information about queries related to partition manipulations, see the [ALTER documentation](../sql-reference/statements/alter/partition.md#alter_manipulations-with-partitions).
 
 A third-party tool is available to automate this approach: [clickhouse-backup](https://github.com/AlexAkulov/clickhouse-backup).
 

docs/en/operations/settings/settings.md

@@ -1599,13 +1599,13 @@ Default value: 268435456.
 
 -   [min\_insert\_block\_size\_bytes](#min-insert-block-size-bytes)
 
-## output_format_pretty_grid_charset {#output-format-pretty-grid-charset}
+## output\_format\_pretty\_grid\_charset {#output-format-pretty-grid-charset}
 
 Allows to change a charset which is used for printing grids borders. Available charsets are following: UTF-8, ASCII.
 
-**Example** 
+**Example**
 
-```text
+``` text
 SET output_format_pretty_grid_charset = 'UTF-8';
 SELECT * FROM a;
 ┌─a─┐
@@ -1619,5 +1619,4 @@ SELECT * FROM a;
 +---+
 ```
 
-
 [Original article](https://clickhouse.tech/docs/en/operations/settings/settings/) <!-- hide -->

docs/en/operations/system-tables/detached_parts.md

@@ -2,8 +2,8 @@
 
 Contains information about detached parts of [MergeTree](../../engines/table-engines/mergetree-family/mergetree.md) tables. The `reason` column specifies why the part was detached.
 
-For user-detached parts, the reason is empty. Such parts can be attached with [ALTER TABLE ATTACH PARTITION\|PART](../../sql-reference/statements/alter.md#alter_attach-partition) command.
+For user-detached parts, the reason is empty. Such parts can be attached with [ALTER TABLE ATTACH PARTITION\|PART](../../sql-reference/statements/alter/partition.md#alter_attach-partition) command.
 
 For the description of other columns, see [system.parts](../../operations/system-tables/parts.md#system_tables-parts).
 
-If part name is invalid, values of some columns may be `NULL`. Such parts can be deleted with [ALTER TABLE DROP DETACHED PART](../../sql-reference/statements/alter.md#alter_drop-detached).
+If part name is invalid, values of some columns may be `NULL`. Such parts can be deleted with [ALTER TABLE DROP DETACHED PART](../../sql-reference/statements/alter/partition.md#alter_drop-detached).