I do not think that the data source api exposes such a thing. You can however proposes to the data source api 2 to be included.
However there are some caveats , because sorted can mean two different things (weak vs strict order). Then, is really a lot of time lost because of sorting? The best thing is to not read data that is not needed at all (see min/max indexes in orc/parquet or bloom filters in Orc). What is not read does not need to be sorted. See also predicate pushdown. > On 4. Dec 2017, at 07:50, Николай Ижиков <nizhikov....@gmail.com> wrote: > > Cross-posting from @user. > > Hello, guys! > > I work on implementation of custom DataSource for Spark Data Frame API and > have a question: > > If I have a `SELECT * FROM table1 ORDER BY some_column` query I can sort data > inside a partition in my data source. > > Do I have a built-in option to tell spark that data from each partition > already sorted? > > It seems that Spark can benefit from usage of already sorted partitions. > By using of distributed merge sort algorithm, for example. > > Does it make sense for you? > > > 28.11.2017 18:42, Michael Artz пишет: >> I'm not sure other than retrieving from a hive table that is already sorted. >> This sounds cool though, would be interested to know this as well >> On Nov 28, 2017 10:40 AM, "Николай Ижиков" <nizhikov....@gmail.com >> <mailto:nizhikov....@gmail.com>> wrote: >> Hello, guys! >> I work on implementation of custom DataSource for Spark Data Frame API >> and have a question: >> If I have a `SELECT * FROM table1 ORDER BY some_column` query I can sort >> data inside a partition in my data source. >> Do I have a built-in option to tell spark that data from each partition >> already sorted? >> It seems that Spark can benefit from usage of already sorted partitions. >> By using of distributed merge sort algorithm, for example. >> Does it make sense for you? >> --------------------------------------------------------------------- >> To unsubscribe e-mail: user-unsubscr...@spark.apache.org >> <mailto:user-unsubscr...@spark.apache.org> > > --------------------------------------------------------------------- > To unsubscribe e-mail: dev-unsubscr...@spark.apache.org > --------------------------------------------------------------------- To unsubscribe e-mail: dev-unsubscr...@spark.apache.org
