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Posted to issues@hive.apache.org by "Janos Kovacs (Jira)" <ji...@apache.org> on 2023/10/24 08:12:00 UTC
[jira] [Updated] (HIVE-27734) Add Iceberg's storage-partitioned join capabilities to Hive's [sorted-]bucket-map-join
[ https://issues.apache.org/jira/browse/HIVE-27734?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Janos Kovacs updated HIVE-27734:
--------------------------------
Summary: Add Iceberg's storage-partitioned join capabilities to Hive's [sorted-]bucket-map-join (was: Add Icenerg's storage-partitioned join capabilities to Hive's [sorted-]bucket-map-join)
> Add Iceberg's storage-partitioned join capabilities to Hive's [sorted-]bucket-map-join
> --------------------------------------------------------------------------------------
>
> Key: HIVE-27734
> URL: https://issues.apache.org/jira/browse/HIVE-27734
> Project: Hive
> Issue Type: Improvement
> Components: Iceberg integration
> Affects Versions: 4.0.0-alpha-2
> Reporter: Janos Kovacs
> Priority: Major
>
> Iceberg's 'data bucketing' is implemented through its rich (function based) partitioning feature which helps to optimize join operations - called storage partitioned joins.
> doc: [https://docs.google.com/document/d/1foTkDSM91VxKgkEcBMsuAvEjNybjja-uHk-r3vtXWFE/edit#heading=h.82w8qxfl2uwl]
> spark impl.: https://issues.apache.org/jira/browse/SPARK-37375
> This feature is not yet leveraged in Hive into its bucket-map-join optimization, neither alone nor with Iceberg's SortOrder to sorted-bucket-map-join.
> Customers migrating from Hive table format to Iceberg format with storage optimized schema will experience performance degradation on large tables where Iceberg's gain on no-listing performance improvement is significantly smaller than the actual join performance over bucket-join or even sorted-bucket-join.
>
> {noformat}
> SET hive.query.results.cache.enabled=false;
> SET hive.fetch.task.conversion = none;
> SET hive.optimize.bucketmapjoin=true;
> SET hive.convert.join.bucket.mapjoin.tez=true;
> SET hive.auto.convert.join.noconditionaltask.size=1000;
> --if you are working with external table, you need this for bmj:
> SET hive.disable.unsafe.external.table.operations=false;
> -- HIVE BUCKET-MAP-JOIN
> DROP TABLE IF EXISTS default.hivebmjt1 PURGE;
> DROP TABLE IF EXISTS default.hivebmjt2 PURGE;
> CREATE TABLE default.hivebmjt1 (id int, txt string) CLUSTERED BY (id) INTO 8 BUCKETS;
> CREATE TABLE default.hivebmjt2 (id int, txt string);
> INSERT INTO default.hivebmjt1 VALUES (1,'1'),(2,'2'),(3,'3'),(4,'4'),(5,'5'),(6,'6'),(7,'7'),(8,'8');
> INSERT INTO default.hivebmjt2 VALUES (1,'1'),(2,'2'),(3,'3'),(4,'4');
> EXPLAIN
> SELECT * FROM default.hivebmjt1 f INNER JOIN default.hivebmjt2 d ON f.id = d.id;
> EXPLAIN
> SELECT * FROM default.hivebmjt1 f LEFT OUTER JOIN default.hivebmjt2 d ON f.id = d.id;
> -- Both are optimized into BMJ
> -- ICEBERG BUCKET-MAP-JOIN via Iceberg's storage-partitioned join
> DROP TABLE IF EXISTS default.icespbmjt1 PURGE;
> DROP TABLE IF EXISTS default.icespbmjt2 PURGE;
> CREATE TABLE default.icespbmjt1 (txt string) PARTITIONED BY (id int) STORED BY ICEBERG ;
> CREATE TABLE default.icespbmjt2 (txt string) PARTITIONED BY (id int) STORED BY ICEBERG ;
> INSERT INTO default.icespbmjt1 VALUES ('1',1),('2',2),('3',3),('4',4);
> INSERT INTO default.icespbmjt2 VALUES ('1',1),('2',2),('3',3),('4',4);
> EXPLAIN
> SELECT * FROM default.icespbmjt1 f INNER JOIN default.icespbmjt2 d ON f.id = d.id;
> EXPLAIN
> SELECT * FROM default.icespbmjt1 f LEFT OUTER JOIN default.icespbmjt2 d ON f.id = d.id;
> -- Only Map-Join optimised
> {noformat}
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