What is the full meaning of the event in query_events?
Posted: Fri Apr 11, 2014 7:58 am
Hi,
Does anyone know what the following events from the query_events table are in detail? Is there anywhere in the documentation that explains them fully? Which ones are bad, good, ok
Does anyone know what the following events from the query_events table are in detail? Is there anywhere in the documentation that explains them fully? Which ones are bad, good, ok
Code: Select all
vertica=> select distinct event_type, event_description from query_events order by 1, 2;
event_type | event_description
--------------------------------------+-------------------------------------------------------------------------------------------------------------
DELETE WITH NON OPTIMIZED PROJECTION | Deleting rows in a projection required the slow path
GROUPBY PUSHDOWN | The optimizer pushed GroupBy past a Join
GROUP_BY_PREPASS_FALLBACK | In-memory prepass disabled due to ineffectiveness.
GROUP_BY_SPILLED | GROUP BY key set did not fit in memory, using external sort grouping.
MEMORY LIMIT HIT | The optimizer used all of its allocated memory while planning
MERGE_CONVERTED_TO_UNION | Merge converted to union, followed by sort.
NO GROUPBY PUSHDOWN | The optimizer couldn't push GroupBy past Join
NO HISTOGRAM | The optimizer encountered a predicate on a column for which it does not have a histogram
PARTITIONS_ELIMINATED | Some storage containers will not be processed because they contain no relevant data.
PREDICATE OUTSIDE HISTOGRAM | The optimizer encountered a predicate that was false for the entire histogram.
RESEGMENTED_MANY_ROWS | Many rows were resegmented during plan execution.
RLE_OVERRIDDEN | Compressed execution will not be used on some columns, because the average run counts are not large enough.
SEQUENCE CACHE REFILLED | Session Cache for a sequence has been used up. Taking a GLOBAL CATALOG X Lock to replenish the cache.
SIP_FALLBACK | Sideways information passing filter disabled due to ineffectiveness.
SMALL_MERGE_REPLACED | Small StorageMerge replaced with StorageUnion for efficiency
TRANSITIVE PREDICATE | The optimizer created a transitive predicate due to a join condition
WOS_SPILL | WOS Full; spilling to a new ROS container
(17 rows)