INSERT and ingestion performance

Answers "why are inserts slow, failing, or creating too many parts" from system.query_log, system.part_log, system.query_views_log, system.kafka_consumers, system.processes and system.text_log. Run altinity-expert-clickhouse-connection first if the connection mode, cluster and time window are not yet established.

Query packs

• checks.sql — 14 checks: Kafka consumer health and scheduling capacity, running and recent insert activity, part creation rate per table, insert vs merge balance, slow inserts, materialized-view overhead on inserts, failed inserts, batch size distribution, Kafka engine ingestion, Kafka messages in the log, Buffer table flush patterns and current insert-related settings. 2 of them need system.part_log, 1 needs system.query_views_log, 1 needs system.text_log.

How to run the query packs

1. Read each pack file from this skill's directory (the skill loader prints the directory path).
2. Run statements one at a time, never a whole file. Statements end with ; and start with a -- @check <id> <title> header; keep the id with its result.
3. Honor -- @requires: skip the statement when the named table is missing, when keeper is required and the server has no Keeper/ZooKeeper, or when the version condition is not met. List skipped ids with the reason.
4. Keep {cluster} as written when a cluster macro exists; otherwise apply the connection skill's rewrite rule. Any other {placeholder} is a template variable: substitute a real value first or skip the statement.
5. On an error, record the check id and the first line of the error, then continue. Only for UNKNOWN_IDENTIFIER, run DESCRIBE TABLE system.<table> and drop the missing column.
6. A severity column is the verdict for that row. Copy it; do not re-grade.

Deep-dive statements