> ## Documentation Index
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> Use this file to discover all available pages before exploring further.

> System table containing information about stack traces for fatal errors.

# system.crash_log

<Info>
  **Querying in ClickHouse Cloud**

  The data in this system table is held locally on each node in ClickHouse Cloud. Obtaining a complete view of all data, therefore, requires the `clusterAllReplicas` function. See [here](/reference/system-tables/overview#system-tables-in-clickhouse-cloud) for further details.
</Info>

<h2 id="description">
  Description
</h2>

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.

<h2 id="columns">
  Columns
</h2>

* `hostname` ([LowCardinality(String)](/reference/data-types/lowcardinality)) — The hostname where the crash occurred.
* `event_date` ([Date](/reference/data-types/date)) — The date of the crash.
* `event_time` ([DateTime](/reference/data-types/datetime)) — The time of the crash.
* `timestamp_ns` ([UInt64](/reference/data-types/int-uint)) — Timestamp of the event with nanoseconds.
* `signal` ([Int32](/reference/data-types/int-uint)) — Signal number.
* `signal_code` ([Int32](/reference/data-types/int-uint)) — Signal code. Provides additional context about the signal cause.
* `thread_id` ([UInt64](/reference/data-types/int-uint)) — Thread ID.
* `query_id` ([String](/reference/data-types/string)) — Query ID.
* `query` ([String](/reference/data-types/string)) — Query text that was being executed when the crash occurred.
* `trace` ([Array(UInt64)](/reference/data-types/array)) — Stack trace at the moment of crash. Each element is a virtual memory address inside ClickHouse server process.
* `trace_full` ([Array(String)](/reference/data-types/array)) — Stack trace at the moment of crash. Each element contains a called method inside ClickHouse server process.
* `fault_address` ([Nullable(UInt64)](/reference/data-types/nullable)) — Memory address that caused the fault.
* `fault_access_type` ([String](/reference/data-types/string)) — Type of memory access that caused the fault (e.g., 'read', 'write').
* `signal_description` ([String](/reference/data-types/string)) — Human-readable description based on signal\_code (e.g., 'Address not mapped to object').
* `current_exception_trace_full` ([Array(String)](/reference/data-types/array)) — Current exception stack trace with symbolized frames (std::terminate crashes only).
* `version` ([String](/reference/data-types/string)) — ClickHouse server version.
* `revision` ([UInt32](/reference/data-types/int-uint)) — ClickHouse server revision.
* `build_id` ([String](/reference/data-types/string)) — BuildID that is generated by compiler.
* `git_hash` ([String](/reference/data-types/string)) — Git commit hash of the ClickHouse source code.
* `architecture` ([String](/reference/data-types/string)) — CPU architecture (e.g., x86\_64, aarch64).

<h2 id="example">
  Example
</h2>

```sql title="Query" theme={null}
SELECT * FROM system.crash_log ORDER BY event_time DESC LIMIT 1;
```

```text title="Response" theme={null}
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:
```

<h2 id="see-also">
  See also
</h2>

* [trace\_log](/reference/system-tables/trace_log) system table