Curious why you think that Parquet does not have metadat at file, row
group or column level.
Please refer here to the type of metadata that Parquet supports in the
docs http://parquet.apache.org/documentation/latest/
n 06/03/2016 15:26, Mich Talebzadeh wrote:
Hi.
I have been hearing a fair bit about Parquet versus ORC tables.
In a nutshell I can say that Parquet is a predecessor to ORC (both
provide columnar type storage) but I notice that it is still being
used especially with Spark users.
In mitigation it appears that Spark users are reluctant to use ORC
despite the fact that with inbuilt Store Index it offers superior
optimisation with data and stats at file, stripe and row group level.
Both Parquet and ORC offer SNAPPY compression as well. ORC offers ZLIB
as default.
There may be other than technical reasons for this adaption, for
example too much reliance on Hive plus the fact that it is easier to
flatten Parquet than ORC (whatever that means).
I for myself use either text files or ORC with Hive and Spark and
don't really see any reason why I should adopt others like Avro,
Parquet etc.
Appreciate any verification or experience on this.
Thanks
,
Dr Mich Talebzadeh
LinkedIn
/https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw/
http://talebzadehmich.wordpress.com <http://talebzadehmich.wordpress.com/>
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