Can in insert data multiple times into a bucketed hive table
bucket, hadoop, hive
Solution
I figured it out!! Actually if you do multiple inserts on a bucketed hive table. Hive wont complain as such. All hive queries will work fine.
Having said that, Such operation spoils the bucketing concept of the table. I mean after multiple inserts into a bucketed table the sampling fails.
The TABLASAMPLE doesnt work properly after multiple inserts.
Even sort merge bucket map join also doesnt work after such operation.
Problem
I have a bucketed hive table. It has 4 buckets. ``` CREATE TABLE user(user_id BIGINT, firstname STRING, lastname STRING) COMMENT 'A bucketed copy of user_info' CLUSTERED BY(user_id) INTO 4 BUCKETS; ``` Initially i have inserted some records into this table using the following query. ``` set hive.enforce.bucketing = true; insert into user select * from second_user; ``` After this operation In HDFS I see that 4 files are created under this table dir. Again i needed to insert another set of data into user table. So i ran the below query. ``` set hive.enforce.bucketing = true; insert into user select * from third_user; ``` Now another 4 files are crated under user folder dir. Now it has total 8 files. Is this fine to do this kind of multiple inserts into a bucketed table? Does it affect the bucketing of the table?