Peter Vary created HIVE-25580:
---------------------------------
Summary: Increase the performance of getTableColumnStatistics and
getPartitionColumnStatistics
Key: HIVE-25580
URL: https://issues.apache.org/jira/browse/HIVE-25580
Project: Hive
Issue Type: Improvement
Components: Standalone Metastore
Reporter: Peter Vary
Assignee: Peter Vary
When the PART_COL_STATS table contains high number of rows the
getTableColumnStatistics and getPartitionColumnStatistics response time
increases.
The root cause is the full table scan for the jdbc query below:
{code:java}
2021-09-27 13:22:44,218 DEBUG DataNucleus.Datastore.Native:
[pool-6-thread-199]: SELECT DISTINCT "A0"."ENGINE" FROM "PART_COL_STATS" "A0"
2021-09-27 13:22:50,569 DEBUG DataNucleus.Datastore.Retrieve:
[pool-6-thread-199]: Execution Time = 6351 ms {code}
The time spent in
[here|https://github.com/apache/hive/blob/ed1882ef569f8d00317597c269cfae35ace5a5fa/standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/ObjectStore.java#L9965]:
{code:java}
query = pm.newQuery(MPartitionColumnStatistics.class);
query.setResult("DISTINCT engine");
Collection names = (Collection) query.execute();
{code}
We might get a better performance if we limit the query range based on the
cat/db/table.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
