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37 lines
1.3 KiB
Markdown
37 lines
1.3 KiB
Markdown
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---
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slug: /en/operations/system-tables/query_cache
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---
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# query_cache
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Shows the content of the [query cache](../query-cache.md).
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Columns:
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- `query` ([String](../../sql-reference/data-types/string.md)) — Query string.
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- `result_size` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Size of the query cache entry.
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- `stale` ([UInt8](../../sql-reference/data-types/int-uint.md)) — If the query cache entry is stale.
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- `shared` ([UInt8](../../sql-reference/data-types/int-uint.md)) — If the query cache entry is shared between multiple users.
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- `compressed` ([UInt8](../../sql-reference/data-types/int-uint.md)) — If the query cache entry is compressed.
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- `expires_at` ([DateTime](../../sql-reference/data-types/datetime.md)) — When the query cache entry becomes stale.
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- `key_hash` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — A hash of the query string, used as a key to find query cache entries.
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**Example**
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``` sql
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SELECT * FROM system.query_cache FORMAT Vertical;
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```
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``` text
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Row 1:
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──────
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query: SELECT 1 SETTINGS use_query_cache = 1
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result_size: 128
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stale: 0
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shared: 0
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compressed: 1
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expires_at: 2023-10-13 13:35:45
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key_hash: 12188185624808016954
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1 row in set. Elapsed: 0.004 sec.
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```
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