Hello Hive Users,
I have created index on table with deferred rebuild.
1) After Index is created I see two tables;
a) MAIN_TABLE
b) MAIN_TABLE_INDEX
No when I do a explain on the table, I see that it is going for table scan
and not index scan ?
MAIN_TABLE
* TableScan*
alias: MAIN_TABLE
Filter Operator
predicate:
expr: (trim(F1) = 'V1')
type: boolean
Is this expected ? Are there any additional steps which should
be done after index is created ?
I found below mentioned text in archives which is from Mark
INSERT OVERWRITE DIRECTORY '/tmp/indexes/x' SELECT `_bucketname`,
`_offsets` FROM default__t_x__
where j='and';
(The name default__t_x__ can be found in the output of step 2. Also,
/tmp/indexes directory
needs to exist in HDFS. You can substitute this to be any pre-existing
directory in HDFS)
SET hive.index.compact.file=/tmp/indexes/x;
SET
hive.input.format=org.apache.hadoop.hive.ql.index.compact.HiveCompactIndexInputFormat;
SELECT a, count(*) from t where j='and' group by a;
Also does join keys use indexes which were created ?
Good wishes,always !
Santosh
