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44 lines
3.5 KiB
Markdown
44 lines
3.5 KiB
Markdown
---
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slug: /en/operations/system-tables/view_refreshes
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---
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# view_refreshes
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Information about [Refreshable Materialized Views](../../sql-reference/statements/create/view.md#refreshable-materialized-view). Contains all refreshable materialized views, regardless of whether there's a refresh in progress or not.
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Columns:
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- `database` ([String](../../sql-reference/data-types/string.md)) — The name of the database the table is in.
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- `view` ([String](../../sql-reference/data-types/string.md)) — Table name.
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- `status` ([String](../../sql-reference/data-types/string.md)) — Current state of the refresh.
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- `last_refresh_result` ([String](../../sql-reference/data-types/string.md)) — Outcome of the latest refresh attempt.
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- `last_refresh_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Time of the last refresh attempt. `NULL` if no refresh attempts happened since server startup or table creation.
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- `last_success_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Time of the last successful refresh. `NULL` if no successful refreshes happened since server startup or table creation.
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- `duration_ms` ([UInt64](../../sql-reference/data-types/int-uint.md)) — How long the last refresh attempt took.
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- `next_refresh_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Time at which the next refresh is scheduled to start.
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- `remaining_dependencies` ([Array(String)](../../sql-reference/data-types/array.md)) — If the view has [refresh dependencies](../../sql-reference/statements/create/view.md#refresh-dependencies), this array contains the subset of those dependencies that are not satisfied for the current refresh yet. If `status = 'WaitingForDependencies'`, a refresh is ready to start as soon as these dependencies are fulfilled.
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- `exception` ([String](../../sql-reference/data-types/string.md)) — if `last_refresh_result = 'Exception'`, i.e. the last refresh attempt failed, this column contains the corresponding error message and stack trace.
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- `refresh_count` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Number of successful refreshes since last server restart or table creation.
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- `progress` ([Float64](../../sql-reference/data-types/float.md)) — Progress of the current refresh, between 0 and 1.
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- `read_rows` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Number of rows read by the current refresh so far.
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- `total_rows` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Estimated total number of rows that need to be read by the current refresh.
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(There are additional columns related to current refresh progress, but they are currently unreliable.)
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**Example**
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```sql
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SELECT
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database,
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view,
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status,
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last_refresh_result,
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last_refresh_time,
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next_refresh_time
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FROM system.view_refreshes
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┌─database─┬─view───────────────────────┬─status────┬─last_refresh_result─┬───last_refresh_time─┬───next_refresh_time─┐
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│ default │ hello_documentation_reader │ Scheduled │ Finished │ 2023-12-01 01:24:00 │ 2023-12-01 01:25:00 │
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└──────────┴────────────────────────────┴───────────┴─────────────────────┴─────────────────────┴─────────────────────┘
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```
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