Revert retention policy for clickhouse system.query_log.#10451
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LGTM, thanks. We should make sure we have a way to drop the "helpfully" renamed system.query_log_$N tables on customer systems.
As described in #10444, there's a bug in setting retention policies on `system.query_log`: because we configure the ttl in config.xml and then optionally overwrite it in sql via retention policies, user-configured ttls on the query log table don't survive clickhouse restarts. Instead, clickhouse moves `system.query_log` to `system.query_log_$ORDINAL`, and creates a new `system.query_log` table using the ttl from config.xml. We could solve this by persisting the user-configured ttl in cockroachdb and propagating that value to config.xml somehow. However, it's simpler to instead make `system.query_log` small enough that we don't have to care about its ttl, and remove it from the retention policy concept. We dropped the size of this table significantly in #10443, and will drop it further by omitting query logs for fast queries in a follow-up patch. In this patch, we drop logic to manage the query log ttl. Fixes #10444.
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As described in #10444, there's a bug in setting retention policies on
system.query_log: because we configure the ttl in config.xml and then optionally overwrite it in sql via retention policies, user-configured ttls on the query log table don't survive clickhouse restarts. Instead, clickhouse movessystem.query_logtosystem.query_log_$ORDINAL, and creates a newsystem.query_logtable using the ttl from config.xml.We could solve this by persisting the user-configured ttl in cockroachdb and propagating that value to config.xml somehow. However, it's simpler to instead make
system.query_logsmall enough that we don't have to care about its ttl, and remove it from the retention policy concept. We dropped the size of this table significantly in #10443, and will drop it further by omitting query logs for fast queries in a follow-up patch. In this patch, we drop logic to manage the query log ttl.Fixes #10444.