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

---
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