Undocumented Implicit Partition Statistics Gathering
A boundary condition where subpartition statistics gathering can also trigger partition statistics Continue Reading
Statistics
Unexpected Optimizer Statistics Collection
Column usage in predicates can trigger statistics collection even when statistics aren’t stale. The problem got worse in 21c. Continue Reading
Performance Problem with Incremental Statistics Calculation
A frequently executed SQL causes problems with the initial incremental statistics calculation. Continue Reading
Incremental Statistics: Histogram Pitfall
The creation of new histograms invalidates synopses. Continue Reading
Wrong Join-Cardinality with Extended Statistics
Wrong cardinality calculation for multi-column join with filter predicate and extended statistics Continue Reading
Gathering Statistics with Option ‘gather auto’
In 12c the parameter options was introduced in gather_table_stats. Unfortunately, it doesn’t work as expected. Continue Reading
Stale index statistics
The gathering of empty schema statistics might cause index statistics to be marked as stale. Continue Reading