Part lifecycle diagnostics

Answers "what is happening to parts, how fast, and is anything failing?" from system.part_log, read as rate (events per minute), volume (rows and bytes) and errors. Run altinity-expert-clickhouse-connection first if the connection mode, cluster and time window are not yet established.

Query packs

• checks.sql — 11 checks: part_log coverage sanity, part activity timeline by minute, NewPart rate per table, merge balance of new parts versus merges, merge duration distribution, MutatePart rate, outstanding mutation backlog, DownloadPart spikes, RemovePart spikes, MovePart spikes, and part_log rows with a non-zero error. Ten of the eleven need system.part_log; only part-log-07 reads system.mutations instead. If system.part_log does not exist, skip every other check and report that part_log is not enabled, since no part-lifecycle conclusion can be drawn without it.
• reference.md — background (event types, part lifecycle, settings); read only when you need to explain a recommendation.

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.