ClickHouse/docs/en/operations/system-tables/crash-log.md

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---
slug: /en/operations/system-tables/crash-log
---
# crash_log
Contains information about stack traces for fatal errors. The table does not exist in the database by default, it is created only when fatal errors occur.
Columns:
- `hostname` ([LowCardinality(String)](../../sql-reference/data-types/string.md)) — Hostname of the server executing the query.
- `event_date` ([DateTime](../../sql-reference/data-types/datetime.md)) — Date of the event.
- `event_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Time of the event.
- `timestamp_ns` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Timestamp of the event with nanoseconds.
- `signal` ([Int32](../../sql-reference/data-types/int-uint.md)) — Signal number.
- `thread_id` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Thread ID.
- `query_id` ([String](../../sql-reference/data-types/string.md)) — Query ID.
- `trace` ([Array](../../sql-reference/data-types/array.md)([UInt64](../../sql-reference/data-types/int-uint.md))) — Stack trace at the moment of crash. Each element is a virtual memory address inside ClickHouse server process.
- `trace_full` ([Array](../../sql-reference/data-types/array.md)([String](../../sql-reference/data-types/string.md))) — Stack trace at the moment of crash. Each element contains a called method inside ClickHouse server process.
- `version` ([String](../../sql-reference/data-types/string.md)) — ClickHouse server version.
- `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse server revision.
- `build_id` ([String](../../sql-reference/data-types/string.md)) — BuildID that is generated by compiler.
**Example**
Query:
``` sql
SELECT * FROM system.crash_log ORDER BY event_time DESC LIMIT 1;
```
Result (not full):
``` text
Row 1:
──────
hostname: clickhouse.eu-central1.internal
event_date: 2020-10-14
event_time: 2020-10-14 15:47:40
timestamp_ns: 1602679660271312710
signal: 11
thread_id: 23624
query_id: 428aab7c-8f5c-44e9-9607-d16b44467e69
trace: [188531193,...]
trace_full: ['3. DB::(anonymous namespace)::FunctionFormatReadableTimeDelta::executeImpl(std::__1::vector<DB::ColumnWithTypeAndName, std::__1::allocator<DB::ColumnWithTypeAndName> >&, std::__1::vector<unsigned long, std::__1::allocator<unsigned long> > const&, unsigned long, unsigned long) const @ 0xb3cc1f9 in /home/username/work/ClickHouse/build/programs/clickhouse',...]
version: ClickHouse 20.11.1.1
revision: 54442
build_id:
```
**See also**
- [trace_log](../../operations/system-tables/trace_log.md) system table