[DISCUSS] Add column operations in Table API

2019-03-10 Thread jincheng sun
Hi, ALL:

Currently, there are already lots of table-level operations available in
Table API such as the select, window, join, etc. Most functionalities can
be accomplished with these APIs. But things may become difficult when there
are too many columns to operate.

The difficulties can be summarized into two categories:

1. Column modification - Users have to specify all the columns even if only
some columns are changed, e.g. adding a column, renaming a column, etc.
2. Column projection - It lacks flexible column operations to express which
columns to be selected. e.g.: there are 100 columns, but the user is only
interested in selecting the 1~10 and 20~40 columns.

So, I propose to add the following features in the Table API:

  1. Add the following operator
- Add/Relace Columns
- Drop columns
- Rename columns

   2. Add column selection utils
- columns(...) - select the specified columns
- -columns(...) - deselect the columns specified

For more details, please check out the Google doc
.
You are welcome to leave a comment in the Google doc

and welcome any email feedback!z

Regards,
Jincheng


[jira] [Created] (FLINK-11871) Introduce LongHashTable to improve performance when join key fits in long

2019-03-10 Thread Kurt Young (JIRA)
Kurt Young created FLINK-11871:
--

 Summary: Introduce LongHashTable to improve performance when join 
key fits in long
 Key: FLINK-11871
 URL: https://issues.apache.org/jira/browse/FLINK-11871
 Project: Flink
  Issue Type: Improvement
  Components: Runtime / Operators
Reporter: Kurt Young






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