Analyzing near-1-second planning time and over 1 million planning shared hits — root cause is pg_statistic table bloat causing backends to cache excessive dead tuple data during CatCacheMiss on first SQL execution
Root cause analysis of a 35-minute partition creation: a 50GB default partition requires full data validation when adding a new partition to ensure no range conflicts
Analyzing why UPDATE fails with 'too many range table entries' while SELECT succeeds: UPDATE triggers all partitions in the plan, causing range table entries to exceed the 65000 limit
Analyzing why a table did not appear in the execution plan of a LEFT JOIN query. The root cause is that the optimizer removed the outer table through JOIN elimination optimization when none of its columns were needed in the output.
Analysis of DELETE throwing 'attempted to delete invisible tuple' while SELECT works fine, tracing through source code to identify VM file corruption as the root cause of the visibility check anomaly
Analyzing the counterintuitive phenomenon where a smaller ORDER BY LIMIT value runs slower, caused by the optimizer underestimating the cost of a backward index scan and choosing the wrong index
Analyzing why an UPDATE became slower after adding partition key filter conditions. The root cause was that partition permission checks caused the optimizer to select the wrong index for all partitions instead of a more selective index.
Analyzing the root cause of wrong index selection in execution plans: stale statistics at month-end causing predicate out-of-bounds, combined with prepared statement caching preventing plan updates even after ANALYZE.
Troubleshooting a cascading hang where logical replication walsender exhausts memory, triggers replication_slot_io waits, and blocks both checkpoint and backup processes
Analyzing why INSERT VALUES occasionally became slow. Through wait event analysis, the root cause was identified as WALWrite lock contention, where WAL flushing became the bottleneck under heavy concurrent writes.