tmp_* server settings

ClickHouse server settings in the tmp_* generated group.

These settings configure the ClickHouse server and are autogenerated from ClickHouse source.

tmp_path

Path on the local filesystem to store temporary data for processing large queries.

• Only one option can be used to configure temporary data storage: tmp_path, tmp_policy, temporary_data_in_cache.
• The trailing slash is mandatory.

Example

<tmp_path>/var/lib/clickhouse/tmp/</tmp_path>

tmp_policy

Policy for storage with temporary data. All files with tmp prefix will be removed at start.

Recommendations for using object storage as tmp_policy:

• Use separate bucket:path on each server
• Use metadata_type=plain
• You may also want to set TTL for this bucket

• Only one option can be used to configure temporary data storage: tmp_path ,tmp_policy, temporary_data_in_cache.
• move_factor, keep_free_space_bytes,max_data_part_size_bytes and are ignored.
• Policy should have exactly one volume

For more information see the MergeTree Table Engine documentation.

Example

When /disk1 is full, temporary data will be stored on /disk2.

<clickhouse>
<storage_configuration>
<disks>
<disk1>
<path>/disk1/</path>
</disk1>
<disk2>
<path>/disk2/</path>
</disk2>
</disks>

<policies>
<tmp_two_disks>
<volumes>
<main>
<disk>disk1</disk>
<disk>disk2</disk>
</main>
</volumes>
</tmp_two_disks>
</policies>
</storage_configuration>

<tmp_policy>tmp_two_disks</tmp_policy>
</clickhouse>