Merge pull request #51198 from den-crane/patch-53

Doc. Notes about mutations_sync

docs/en/operations/settings/settings.md

@@ -2941,7 +2941,7 @@ Default value: `0`.
 
 ## mutations_sync {#mutations_sync}
 
-Allows to execute `ALTER TABLE ... UPDATE|DELETE` queries ([mutations](../../sql-reference/statements/alter/index.md#mutations)) synchronously.
+Allows to execute `ALTER TABLE ... UPDATE|DELETE|MATERIALIZE INDEX|MATERIALIZE PROJECTION|MATERIALIZE COLUMN` queries ([mutations](../../sql-reference/statements/alter/index.md#mutations)) synchronously.
 
 Possible values:
 

docs/en/sql-reference/statements/alter/column.md

@@ -232,6 +232,7 @@ ALTER TABLE table_with_ttl MODIFY COLUMN column_ttl REMOVE TTL;
 
 Materializes or updates a column with an expression for a default value (`DEFAULT` or `MATERIALIZED`).
 It is used if it is necessary to add or update a column with a complicated expression, because evaluating such an expression directly on `SELECT` executing turns out to be expensive. 
+Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
 
 Syntax:
 

docs/en/sql-reference/statements/alter/index.md

@@ -60,7 +60,7 @@ You can specify how long (in seconds) to wait for inactive replicas to execute a
 For all `ALTER` queries, if `alter_sync = 2` and some replicas are not active for more than the time, specified in the `replication_wait_for_inactive_replica_timeout` setting, then an exception `UNFINISHED` is thrown.
 :::
 
-For `ALTER TABLE ... UPDATE|DELETE` queries the synchronicity is defined by the [mutations_sync](/docs/en/operations/settings/settings.md/#mutations_sync) setting.
+For `ALTER TABLE ... UPDATE|DELETE|MATERIALIZE INDEX|MATERIALIZE PROJECTION|MATERIALIZE COLUMN` queries the synchronicity is defined by the [mutations_sync](/docs/en/operations/settings/settings.md/#mutations_sync) setting.
 
 ## Related content
 

docs/en/sql-reference/statements/alter/projection.md

@@ -142,19 +142,19 @@ The following operations with [projections](/docs/en/engines/table-engines/merge
 
 ## ADD PROJECTION
 
-`ALTER TABLE [db].name ADD PROJECTION [IF NOT EXISTS] name ( SELECT <COLUMN LIST EXPR> [GROUP BY] [ORDER BY] )` - Adds projection description to tables metadata.
+`ALTER TABLE [db.]name [ON CLUSTER cluster] ADD PROJECTION [IF NOT EXISTS] name ( SELECT <COLUMN LIST EXPR> [GROUP BY] [ORDER BY] )` - Adds projection description to tables metadata.
 
 ## DROP PROJECTION
 
-`ALTER TABLE [db].name DROP PROJECTION [IF EXISTS] name` - Removes projection description from tables metadata and deletes projection files from disk. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
+`ALTER TABLE [db.]name [ON CLUSTER cluster] DROP PROJECTION [IF EXISTS] name` - Removes projection description from tables metadata and deletes projection files from disk. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
 
 ## MATERIALIZE PROJECTION
 
-`ALTER TABLE [db.]table MATERIALIZE PROJECTION name IN PARTITION partition_name` - The query rebuilds the projection `name` in the partition `partition_name`. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
+`ALTER TABLE [db.]table [ON CLUSTER cluster] MATERIALIZE PROJECTION [IF EXISTS] name [IN PARTITION partition_name]` - The query rebuilds the projection `name` in the partition `partition_name`. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
 
 ## CLEAR PROJECTION
 
-`ALTER TABLE [db.]table CLEAR PROJECTION [IF EXISTS] name IN PARTITION partition_name` - Deletes projection files from disk without removing description. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
+`ALTER TABLE [db.]table [ON CLUSTER cluster] CLEAR PROJECTION [IF EXISTS] name [IN PARTITION partition_name]` - Deletes projection files from disk without removing description. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
 
 
 The commands `ADD`, `DROP` and `CLEAR` are lightweight in a sense that they only change metadata or remove files.

docs/en/sql-reference/statements/alter/skipping-index.md

@@ -10,15 +10,25 @@ sidebar_label: INDEX
 
 The following operations are available:
 
-- `ALTER TABLE [db].table_name [ON CLUSTER cluster] ADD INDEX name expression TYPE type [GRANULARITY value] [FIRST|AFTER name]` - Adds index description to tables metadata.
+## ADD INDEX
 
-- `ALTER TABLE [db].table_name [ON CLUSTER cluster] DROP INDEX name` - Removes index description from tables metadata and deletes index files from disk. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
+`ALTER TABLE [db.]table_name [ON CLUSTER cluster] ADD INDEX [IF NOT EXISTS] name expression TYPE type [GRANULARITY value] [FIRST|AFTER name]` - Adds index description to tables metadata.
 
-- `ALTER TABLE [db.]table_name [ON CLUSTER cluster] MATERIALIZE INDEX name [IN PARTITION partition_name]` - Rebuilds the secondary index `name` for the specified `partition_name`. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations). If `IN PARTITION` part is omitted then it rebuilds the index for the whole table data.
+## DROP INDEX
 
-The first two commands are lightweight in a sense that they only change metadata or remove files.
+`ALTER TABLE [db.]table_name [ON CLUSTER cluster] DROP INDEX [IF EXISTS] name` - Removes index description from tables metadata and deletes index files from disk. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
 
-Also, they are replicated, syncing indices metadata via ZooKeeper.
+## MATERIALIZE INDEX
+
+`ALTER TABLE [db.]table_name [ON CLUSTER cluster] MATERIALIZE INDEX [IF EXISTS] name [IN PARTITION partition_name]` - Rebuilds the secondary index `name` for the specified `partition_name`. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations). If `IN PARTITION` part is omitted then it rebuilds the index for the whole table data.
+
+## CLEAR INDEX
+
+`ALTER TABLE [db.]table_name [ON CLUSTER cluster] CLEAR INDEX [IF EXISTS] name [IN PARTITION partition_name]` - Deletes the secondary index files from disk without removing description. Implemented as a [mutation](/docs/en/sql-reference/statements/alter/index.md#mutations).
+
+
+The commands `ADD`, `DROP`, and `CLEAR` are lightweight in the sense that they only change metadata or remove files.
+Also, they are replicated, syncing indices metadata via ClickHouse Keeper or ZooKeeper.
 
 :::note    
 Index manipulation is supported only for tables with [`*MergeTree`](/docs/en/engines/table-engines/mergetree-family/mergetree.md) engine (including [replicated](/docs/en/engines/table-engines/mergetree-family/replication.md) variants).