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---
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slug: /en/operations/caches
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sidebar_position: 65
sidebar_label: Caches
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title: "Cache Types"
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---
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When performing queries, ClickHouse uses different caches.
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Main cache types:
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- `mark_cache` — Cache of marks used by table engines of the [MergeTree ](../engines/table-engines/mergetree-family/mergetree.md ) family.
- `uncompressed_cache` — Cache of uncompressed data used by table engines of the [MergeTree ](../engines/table-engines/mergetree-family/mergetree.md ) family.
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- Operating system page cache (used indirectly, for files with actual data).
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Additional cache types:
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- DNS cache.
- [Regexp ](../interfaces/formats.md#data-format-regexp ) cache.
- Compiled expressions cache.
- [Avro format ](../interfaces/formats.md#data-format-avro ) schemas cache.
- [Dictionaries ](../sql-reference/dictionaries/index.md ) data cache.
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- Schema inference cache.
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- [Filesystem cache ](storing-data.md ) over S3, Azure, Local and other disks.
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To drop one of the caches, use [SYSTEM DROP ... CACHE ](../sql-reference/statements/system.md#drop-mark-cache ) statements.
