Summary

This PR introduces a configurable option to enable/disable query history recording in Trino Gateway, addressing database performance bottlenecks and infrastructure cost concerns.

Problem

Currently, query history is always saved to the database, which creates several operational challenges:

• Database becomes a bottleneck under high query loads, causing performance degradation
• Forces operators to scale up database instances to handle the write load
• Increases infrastructure costs significantly due to larger DB instance requirements
• Query history may not be needed in all deployment scenarios (dev/test environments, alternative monitoring solutions)

Solution

Added a new configuration option queryHistoryEnabled in RoutingConfiguration that allows operators to:

• Disable query history recording when not needed
• Use lower-tier database instances, reducing operational costs
• Improve overall gateway performance by eliminating unnecessary database writes
• Maintain flexibility to enable/disable based on deployment requirements

Configuration

routing:
# Enable or disable query history recording to database (default: true)
queryHistoryEnabled: false # Set to false to disable query history recording

Default behavior: Query history is enabled by default (true) to maintain backward compatibility.

Benefits

• ✅ Eliminated database bottleneck - No more query history writes under high load
• ✅ Significant cost savings - Can use smaller, cheaper database instances
• ✅ Improved gateway performance - Reduced database round trips
• ✅ Operational flexibility - Enable/disable based on environment needs
• ✅ Backward compatible - Existing deployments continue working unchanged

Implementation Details

Core Changes

• RoutingConfiguration.java: Added queryHistoryEnabled boolean field with getter/setter (defaults to true)
• ProxyRequestHandler.java: Added conditional check before queryHistoryManager.submitQueryDetail() to respect the configuration flag
• config.yaml: Added configuration example with inline documentation

Test Coverage

Added comprehensive test suite covering all scenarios:

• TestRoutingConfiguration: Unit tests for configuration parsing and defaults (3 tests)
• TestProxyRequestHandlerQueryHistoryEnabled: Integration test validating queries ARE recorded when enabled
• TestProxyRequestHandlerQueryHistoryDisabled: Integration test validating queries are NOT recorded when disabled
• test-config-with-query-history-disabled.yml: Test configuration file for disabled scenario

All tests pass: 290 tests run, 0 failures, 0 errors

Backward Compatibility

✅ Fully backward compatible

• Default value is true, maintaining existing behavior
• Existing configurations without this setting will continue to record query history
• No database schema changes required
• No breaking changes to APIs or interfaces

Files Changed

Production Code (3 files)

• gateway-ha/src/main/java/io/trino/gateway/ha/config/RoutingConfiguration.java
• gateway-ha/src/main/java/io/trino/gateway/proxyserver/ProxyRequestHandler.java
• gateway-ha/config.yaml

Test Code (5 files)

• gateway-ha/src/test/java/io/trino/gateway/ha/config/TestRoutingConfiguration.java
• gateway-ha/src/test/java/io/trino/gateway/proxyserver/TestProxyRequestHandlerQueryHistoryEnabled.java
• gateway-ha/src/test/java/io/trino/gateway/proxyserver/TestProxyRequestHandlerQueryHistoryDisabled.java
• gateway-ha/src/test/resources/test-config-template.yml
• gateway-ha/src/test/resources/test-config-with-query-history-disabled.yml

Follow-up

After this PR is approved and merged, a follow-up PR will be submitted to the Trino Gateway Helm Charts repository to expose this configuration option in the Helm values, making it easier for Kubernetes deployments to configure this setting.