cameleer-server/cameleer-server-app/src/main/resources/clickhouse/alerting_projections.sql

-- Alerting projections — additive and idempotent (IF NOT EXISTS).
-- Safe to run on every startup alongside init.sql.
--
-- executions uses ReplacingMergeTree. ClickHouse 24.x requires deduplicate_merge_projection_mode='rebuild'
-- for projections to work on ReplacingMergeTree. ALTER TABLE MODIFY SETTING persists the setting in
-- table metadata (survives restarts) and runs before the ADD PROJECTION statements.
-- logs and agent_metrics use plain MergeTree and do not need this setting.
--
-- MATERIALIZE statements are wrapped as non-fatal to handle empty tables in fresh deployments.

-- Plain MergeTree tables: always succeed
ALTER TABLE logs
    ADD PROJECTION IF NOT EXISTS alerting_app_level
    (SELECT * ORDER BY (tenant_id, environment, application, level, timestamp));

ALTER TABLE agent_metrics
    ADD PROJECTION IF NOT EXISTS alerting_instance_metric
    (SELECT * ORDER BY (tenant_id, environment, instance_id, metric_name, collected_at));

-- ReplacingMergeTree: set table-level setting so ADD PROJECTION succeeds on any connection
ALTER TABLE executions MODIFY SETTING deduplicate_merge_projection_mode = 'rebuild';

ALTER TABLE executions
    ADD PROJECTION IF NOT EXISTS alerting_app_status
    (SELECT * ORDER BY (tenant_id, environment, application_id, status, start_time));

ALTER TABLE executions
    ADD PROJECTION IF NOT EXISTS alerting_route_status
    (SELECT * ORDER BY (tenant_id, environment, route_id, status, start_time));

-- MATERIALIZE: best-effort on all tables (non-fatal if table is empty or already running)
ALTER TABLE logs          MATERIALIZE PROJECTION alerting_app_level;
ALTER TABLE agent_metrics MATERIALIZE PROJECTION alerting_instance_metric;
ALTER TABLE executions    MATERIALIZE PROJECTION alerting_app_status;
ALTER TABLE executions    MATERIALIZE PROJECTION alerting_route_status;