system.opentelemetry_span_log

System table containing information about trace spans for executed queries.

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 for further details.

Description

Contains information about trace spans for executed queries.

It is safe to truncate or drop this table at any time.

Columns

• hostname (LowCardinality(String)) — The hostname where this span was captured.
• clickhouse_version (LowCardinality(String)) — Version of the ClickHouse server that produced the row.
• system_processor (LowCardinality(String)) — CPU architecture of the ClickHouse server that produced the row.
• trace_id (UUID) — ID of the trace for executed query.
• span_id (UInt64) — ID of the trace span.
• parent_span_id (UInt64) — ID of the parent trace span.
• operation_name (LowCardinality(String)) — The name of the operation.
• kind (Enum8(‘INTERNAL’ = 0, ‘SERVER’ = 1, ‘CLIENT’ = 2, ‘PRODUCER’ = 3, ‘CONSUMER’ = 4)) — The SpanKind of the span. INTERNAL — Indicates that the span represents an internal operation within an application. SERVER — Indicates that the span covers server-side handling of a synchronous RPC or other remote request. CLIENT — Indicates that the span describes a request to some remote service. PRODUCER — Indicates that the span describes the initiators of an asynchronous request. This parent span will often end before the corresponding child CONSUMER span, possibly even before the child span starts. CONSUMER - Indicates that the span describes a child of an asynchronous PRODUCER request.
• start_time_us (UInt64) — The start time of the trace span (in microseconds).
• finish_time_us (UInt64) — The finish time of the trace span (in microseconds).
• finish_date (Date) — The finish date of the trace span.
• status_code (Enum8(‘UNSET’ = 0, ‘OK’ = 1, ‘ERROR’ = 2)) — The status code of the span.
• status_message (LowCardinality(String)) — Error message.
• attribute (Map(LowCardinality(String), String)) — Attribute depending on the trace span. They are filled in according to the recommendations in the OpenTelemetry standard.

Aliases:

• attribute.names — Alias for mapKeys(attribute).
• attribute.values — Alias for mapValues(attribute).

Example

Query

SELECT * FROM system.opentelemetry_span_log LIMIT 1 FORMAT Vertical;

Response

Row 1:
──────
trace_id:         cdab0847-0d62-61d5-4d38-dd65b19a1914
span_id:          701487461015578150
parent_span_id:   2991972114672045096
operation_name:   DB::Block DB::InterpreterSelectQuery::getSampleBlockImpl()
kind:             INTERNAL
start_time_us:    1612374594529090
finish_time_us:   1612374594529108
finish_date:      2021-02-03
attribute.names:  []
attribute.values: []

See Also

• OpenTelemetry