-- Tags: no-parallel -- Tag no-parallel: Messes with internal cache SYSTEM DROP QUERY CACHE; -- DROP TABLE system.query_log; -- debugging SELECT '-- Run a query with query cache not enabled'; SELECT 124437993; SYSTEM FLUSH LOGS; -- Field 'query_cache_usage' should be 'None' SELECT type, query, query_cache_usage FROM system.query_log WHERE current_database = currentDatabase() AND query = 'SELECT 124437993;' AND type = 'QueryFinish' ORDER BY type, query_cache_usage; SELECT '-- Run a query with query cache enabled'; SELECT 124437994 SETTINGS use_query_cache = 1; SYSTEM FLUSH LOGS; -- Field 'query_cache_usage' should be 'Write' SELECT type, query, query_cache_usage FROM system.query_log WHERE current_database = currentDatabase() AND query = 'SELECT 124437994 SETTINGS use_query_cache = 1;' AND type = 'QueryFinish' ORDER BY type, query_cache_usage; SELECT '-- Run the same query with query cache enabled'; SELECT 124437994 SETTINGS use_query_cache = 1; SYSTEM FLUSH LOGS; -- Field 'query_cache_usage' should be 'Read' SELECT type, query, query_cache_usage FROM system.query_log WHERE current_database = currentDatabase() AND query = 'SELECT 124437994 SETTINGS use_query_cache = 1;' AND type = 'QueryFinish' ORDER BY type, query_cache_usage; SELECT '-- Throw exception with query cache enabled'; SELECT 124437995, throwIf(1) SETTINGS use_query_cache = 1; -- { serverError FUNCTION_THROW_IF_VALUE_IS_NON_ZERO } SYSTEM FLUSH LOGS; -- Field 'query_cache_usage' should be 'None' SELECT query, query_cache_usage FROM system.query_log WHERE current_database = currentDatabase() AND query = 'SELECT 124437995, throwIf(1) SETTINGS use_query_cache = 1;' AND type = 'ExceptionWhileProcessing'; SYSTEM DROP QUERY CACHE;