LogsQL dialect in ClickHouse

Overview

ClickHouse provides an experimental logsql dialect for querying log tables with VictoriaLogs LogsQL syntax. It translates a LogsQL query to a ClickHouse SELECT query. Enable it for a session and configure the source table:

SET allow_experimental_logsql_dialect = 1;
SET logsql_database = 'default';
SET logsql_table = 'logs';
SET logsql_time_column = '_time';
SET logsql_message_column = '_msg';
SET dialect = 'logsql';

The configured table must contain the time and message columns. LogsQL filters, stream filters, text and numeric comparisons, time ranges, and pipe operations such as fields, stats, sort, limit, format, extract, and unpack_json are supported. Text filters expect String-backed log columns; typed fields can be used with numeric comparisons and numeric statistics. This dialect is experimental and is not a byte-for-byte implementation of VictoriaLogs. Unsupported syntax is rejected with NOT_IMPLEMENTED; query semantics can also differ where ClickHouse types, regular expressions, time zones, or SQL aggregation rules differ. Use ordinary ClickHouse SQL when a LogsQL construct is not supported or exact VictoriaLogs compatibility is needed.

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Overview

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Overview