I've created an external hive table stored in "/cntt_sondn/hive/tables/test_orc" in hdfs using command:create external table test_lab.test_orc (col1 string, col2 string) stored as orc location '/cntt_sondn/hive/tables/test_orc';. It seems ok and the directory was created successfully by user hive. Then, I use NiFi to put a orc file in the directory, there's no problem, no error or warning thrown. However, when I browse to directory on NameNode UI, there are 2 directory with same name "test_orc", ones created by hive, the other created by my user. See image below:
In addition, it seems NiFi puts my orc file in the directory owned by user ra_vtg, so the directory created by user hive is empty. Therefore, no data inserted into the hive table.
Please explain why can these strange things happen.