ClickHouse/docs/zh/operations/system-tables/query_views_log.md

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2022-08-26 19:07:59 +00:00
---
slug: /zh/operations/system-tables/query_views_log
---
2021-10-27 05:28:24 +00:00
# system.query_views_log {#system_tables-query_views_log}
包含有关运行查询时执行的从属视图的信息,例如视图类型或执行时间.
开始记录:
1. 在 [query_views_log](../../operations/server-configuration-parameters/settings.md#server_configuration_parameters-query_views_log) 部分配置参数.
2. 设置 [log_query_views](../../operations/settings/settings.md#settings-log-query-views) 为 1.
数据的刷新周期是在[query_views_log](../../operations/server-configuration-parameters/settings.md#server_configuration_parameters-query_views_log)服务器设置部分的 `flush_interval_milliseconds` 参数中设置的. 要强制刷新,请使用[SYSTEM FLUSH LOGS](../../sql-reference/statements/system.md#query_language-system-flush_logs)查询.
ClickHouse不会自动从表中删除数据. 详见 [Introduction](../../operations/system-tables/index.md#system-tables-introduction).
您可以使用[log_queries_probability](../../operations/settings/settings.md#log-queries-probability)设置来减少在 `query_views_log` 表中注册的查询数量.
列信息:
- `event_date` ([Date](../../sql-reference/data-types/date.md)) — 视图的最后一个事件发生的日期.
- `event_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — 视图完成执行的日期和时间.
- `event_time_microseconds` ([DateTime](../../sql-reference/data-types/datetime.md)) — 视图以微秒精度完成执行的日期和时间.
- `view_duration_ms` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 视图执行的持续时间(各阶段之和), 以毫秒为单位.
- `initial_query_id` ([String](../../sql-reference/data-types/string.md)) — 初始查询的ID (用于分布式查询执行).
- `view_name` ([String](../../sql-reference/data-types/string.md)) — 视图名称.
- `view_uuid` ([UUID](../../sql-reference/data-types/uuid.md)) — 视图的UUID.
- `view_type` ([Enum8](../../sql-reference/data-types/enum.md)) — 视图类型. 值:
- `'Default' = 1` — [Default views](../../sql-reference/statements/create/view.md#normal). 不应该出现在日志中.
- `'Materialized' = 2` — [Materialized views](../../sql-reference/statements/create/view.md#materialized).
- `'Live' = 3` — [Live views](../../sql-reference/statements/create/view.md#live-view).
- `view_query` ([String](../../sql-reference/data-types/string.md)) — 视图执行的查询.
- `view_target` ([String](../../sql-reference/data-types/string.md)) — 视图目标表的名称.
- `read_rows` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 读行数.
- `read_bytes` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 读字节数.
- `written_rows` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 写入行数.
- `written_bytes` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 写入字节数.
- `peak_memory_usage` ([Int64](../../sql-reference/data-types/int-uint.md)) — 在此视图上下文中, 已分配内存和已释放内存之间的最大差值.
- `ProfileEvents` ([Map(String, UInt64)](../../sql-reference/data-types/array.md)) — ProfileEvents度量不同的指标. 它们的描述可以在表 [system.events](../../operations/system-tables/events.md#system_tables-events) 中找到.
- `status` ([Enum8](../../sql-reference/data-types/enum.md)) — 视图状态. 值:
- `'QueryStart' = 1` — 成功启动视图执行. 不应该出现.
- `'QueryFinish' = 2` — 视图执行成功结束.
- `'ExceptionBeforeStart' = 3` — 视图执行开始前的异常.
- `'ExceptionWhileProcessing' = 4` — 视图执行期间的异常.
- `exception_code` ([Int32](../../sql-reference/data-types/int-uint.md)) — 异常代码.
- `exception` ([String](../../sql-reference/data-types/string.md)) — 异常报文.
- `stack_trace` ([String](../../sql-reference/data-types/string.md)) — [堆栈跟踪](https://en.wikipedia.org/wiki/Stack_trace). 如果查询成功完成, 则为空字符串.
**示例**
查询:
``` sql
SELECT * FROM system.query_views_log LIMIT 1 \G;
```
结果:
``` text
Row 1:
──────
event_date: 2021-06-22
event_time: 2021-06-22 13:23:07
event_time_microseconds: 2021-06-22 13:23:07.738221
view_duration_ms: 0
initial_query_id: c3a1ac02-9cad-479b-af54-9e9c0a7afd70
view_name: default.matview_inner
view_uuid: 00000000-0000-0000-0000-000000000000
view_type: Materialized
view_query: SELECT * FROM default.table_b
view_target: default.`.inner.matview_inner`
read_rows: 4
read_bytes: 64
written_rows: 2
written_bytes: 32
peak_memory_usage: 4196188
ProfileEvents: {'FileOpen':2,'WriteBufferFromFileDescriptorWrite':2,'WriteBufferFromFileDescriptorWriteBytes':187,'IOBufferAllocs':3,'IOBufferAllocBytes':3145773,'FunctionExecute':3,'DiskWriteElapsedMicroseconds':13,'InsertedRows':2,'InsertedBytes':16,'SelectedRows':4,'SelectedBytes':48,'ContextLock':16,'RWLockAcquiredReadLocks':1,'RealTimeMicroseconds':698,'SoftPageFaults':4,'OSReadChars':463}
status: QueryFinish
exception_code: 0
exception:
stack_trace:
```
**另请参阅**
- [system.query_log](../../operations/system-tables/query_log.md#system_tables-query_log) — 包含查询执行的常用信息的 `query_log`系统表的描述.
- [system.query_thread_log](../../operations/system-tables/query_thread_log.md#system_tables-query_thread_log) — 包含关于每个查询执行线程的信息.