Prasanth Jayachandran created HIVE-21924:
--------------------------------------------
Summary: Split text files if only header/footer is present
Key: HIVE-21924
URL: https://issues.apache.org/jira/browse/HIVE-21924
Project: Hive
Issue Type: Improvement
Components: File Formats
Affects Versions: 2.4.0, 4.0.0, 3.2.0
Reporter: Prasanth Jayachandran
https://github.com/apache/hive/blob/967a1cc98beede8e6568ce750ebeb6e0d048b8ea/ql/src/java/org/apache/hadoop/hive/ql/io/HiveInputFormat.java#L494-L503
this piece of code makes the CSV (or any text files with header/footer) files
not splittable if header or footer is present.
If only header is present, we can find the offset after first line break and
use that to split. Similarly for footer, may be read few KB's of data at the
end and find the last line break offset. Use that to determine the data range
which can be used for splitting. Few reads during split generation are cheaper
than not splitting the file at all.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
