diff --git a/ReadMe.md b/ReadMe.md index 101df4a0..4530bddc 100644 --- a/ReadMe.md +++ b/ReadMe.md @@ -70,7 +70,10 @@ GO111MODULE=on go install github.com/Altinity/clickhouse-backup/v2/cmd/clickhous ## Brief description how clickhouse-backup works -Data files are immutable in the `clickhouse-server`. During a backup operation, `clickhouse-backup` creates file system hard links to existing `clickhouse-server` data parts via executing the `ALTER TABLE ... FREEZE` query. During the restore operation, `clickhouse-backup` copies the hard links to the `detached` folder and executes the `ALTER TABLE ... ATTACH PART` query for each data part and each table in the backup. A more detailed description is available here: https://www.youtube.com/watch?v=megsNh9Q-dw +Data files are immutable in the `clickhouse-server`. +During a backup operation, `clickhouse-backup` creates file system hard links to existing `clickhouse-server` data parts via executing the `ALTER TABLE ... FREEZE` query. +During the restore operation, `clickhouse-backup` copies the hard links to the `detached` folder and executes the `ALTER TABLE ... ATTACH PART` query for each data part and each table in the backup. +A more detailed description is available here: https://www.youtube.com/watch?v=megsNh9Q-dw ## Default Config