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lightweight_* session settings

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These settings are available in system.settings and are autogenerated from source.

lightweight_delete_mode

Type
LightweightDeleteMode
Default
alter_update
Version history
VersionDefault valueComment
25.5alter_updateA new setting

A mode of internal update query that is executed as a part of lightweight delete.

Possible values:

  • alter_update - run ALTER UPDATE query that creates a heavyweight mutation.
  • lightweight_update - run lightweight update if possible, run ALTER UPDATE otherwise.
  • lightweight_update_force - run lightweight update if possible, throw otherwise.

lightweight_deletes_sync

Type
UInt64
Default
2
Version history
VersionDefault valueComment
24.42The same as 'mutation_sync', but controls only execution of lightweight deletes

The same as mutations_sync, but controls only execution of lightweight deletes.

Possible values:

Value Description
0 Mutations execute asynchronously.
1 The query waits for the lightweight deletes to complete on the current server.
2 The query waits for the lightweight deletes to complete on all replicas (if they exist).
3 The query waits only for active replicas. Supported only for SharedMergeTree. For ReplicatedMergeTree it behaves the same as mutations_sync = 2.

See Also

Cloud default value: 1.

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