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https://issues.apache.org/jira/browse/HIVE-1173?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Namit Jain updated HIVE-1173:
-----------------------------
Status: Open (was: Patch Available)
comments on phabricator
> Partition pruner cancels pruning if non-deterministic function present in
> filtering expression only in joins is present in query
> --------------------------------------------------------------------------------------------------------------------------------
>
> Key: HIVE-1173
> URL: https://issues.apache.org/jira/browse/HIVE-1173
> Project: Hive
> Issue Type: Bug
> Components: Query Processor
> Affects Versions: 0.4.1, 0.4.0, 0.10.0
> Reporter: Vladimir Klimontovich
> Assignee: Navis
>
> Brief description:
> case 1) non-deterministic present in partition condition, joins are present
> in query => partition pruner doesn't do filtering of partitions based on
> condition
> case 2) non-deterministic present in partition condition, joins aren't
> present in query => partition pruner do filtering of partitions based on
> condition
> It's quite illogical when pruning depends on presence of joins in query.
> Example:
> Let's consider following sequence of hive queries:
> 1) Create non-deterministic function:
> create temporary function UDF2 as 'UDF2';
> {{
> import org.apache.hadoop.hive.ql.exec.UDF;
> import org.apache.hadoop.hive.ql.udf.UDFType;
> @UDFType(deterministic=false)
> public class UDF2 extends UDF {
> public String evaluate(String val) {
> return val;
> }
> }
> }}
> 2) Create tables
> CREATE TABLE Main (
> a STRING,
> b INT
> )
> PARTITIONED BY(part STRING)
> ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t'
> LINES TERMINATED BY '10'
> STORED AS TEXTFILE;
> ALTER TABLE Main ADD PARTITION (part="part1") LOCATION
> "/hive-join-test/part1/";
> ALTER TABLE Main ADD PARTITION (part="part2") LOCATION
> "/hive-join-test/part2/";
> CREATE TABLE Joined (
> a STRING,
> f STRING
> )
> ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t'
> LINES TERMINATED BY '10'
> STORED AS TEXTFILE
> LOCATION '/hive-join-test/join/';
> 3) Run first query:
> select
> m.a,
> m.b
> from Main m
> where
> part > UDF2('part0') AND part = 'part1';
> The pruner will work for this query:
> mapred.input.dir=hdfs://localhost:9000/hive-join-test/part1
> 4) Run second query (with join):
> select
> m.a,
> j.a,
> m.b
> from Main m
> join Joined j on
> j.a=m.a
> where
> part > UDF2('part0') AND part = 'part1';
> Pruner doesn't work:
> mapred.input.dir=hdfs://localhost:9000/hive-join-test/part1,hdfs://localhost:9000/hive-join-test/part2,hdfs://localhost:9000/hive-join-test/join
> 5) Also lets try to run query with MAPJOIN hint
> select /*+MAPJOIN(j)*/
> m.a,
> j.a,
> m.b
> from Main m
> join Joined j on
> j.a=m.a
> where
> part > UDF2('part0') AND part = 'part1';
> The result is the same, pruner doesn't work:
> mapred.input.dir=hdfs://localhost:9000/hive-join-test/part1,hdfs://localhost:9000/hive-join-test/part2
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