thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-09-20 08:40:50 +00:00
Code Issues Packages Projects Releases Wiki Activity

Update alter.md

Browse Source 
Fix for alter attach alter_attach-partition (fixes #5312). English version.
This commit is contained in:
Denis Zhuravlev 2019-11-27 19:49:13 -04:00 committed by GitHub
parent d8fa0871b9
commit c06496c115
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
docs/en/query_language/alter.md
View File

@ -253,7 +253,7 @@ ALTER TABLE visits ATTACH PART 201901_2_2_0;
Read more about setting the partition expression in a section [How to specify the partition expression](#alter-how-to-specify-part-expr).
This query is replicated. Each replica checks whether there is data in the `detached` directory. If the data is in this directory, the query checks the integrity, verifies that it matches the data on the server that initiated the query. If everything is correct, the query adds data to the replica. If not, it downloads data from the query requestor replica, or from another replica where the data has already been added.
This query is replicated. The replica-initiator checks whether there is data in the `detached` directory. If data exists, the query checks its integrity. If everything is correct, the query adds the data to the table. All other replicas download the data from the replica-initiator.
So you can put data to the `detached` directory on one replica, and use the `ALTER ... ATTACH` query to add it to the table on all replicas.