[Datafusion] Error with CAST: Unsupported SQL type Time

[alamb]

Note: migrated from original JIRA: https://issues.apache.org/jira/browse/ARROW-12232

select cast(timestamp as Time) from foo limit 5;
NotImplemented("Unsupported SQL type Time")

[alamb]

Comment from Evan Chan(velvia) @ 2021-04-14T20:47:50.722+0000:

After discussion for the above PR, seems like the above PR does not really solve this issue, and thus will be amended or left.  A related bug/feature will be filed instead.

[velvia]

I'll leave this ticket for tracking implementing CAST() for Time type, and the discussion from the above PR I'll open a separate issue for to_timestamp_x

[Jefffrey]

Issue seems resolved as of 406c108

jeffrey:~/Code/arrow-datafusion/datafusion-cli$ cargo run
    Finished dev [unoptimized + debuginfo] target(s) in 0.10s
     Running `/media/jeffrey/1tb_860evo_ssd/.cargo_target_cache/debug/datafusion-cli`
DataFusion CLI v14.0.0
❯ select cast(b.timestamp as time) from (select now() as timestamp) b;
+--------------------+
| b.timestamp        |
+--------------------+
| 11:10:31.506762991 |
+--------------------+
1 row in set. Query took 0.004 seconds.
❯ explain select cast(b.timestamp as time) from (select now() as timestamp) b;
+---------------+---------------------------------------------------------------------------------------+
| plan_type     | plan                                                                                  |
+---------------+---------------------------------------------------------------------------------------+
| logical_plan  | Projection: CAST(b.timestamp AS Time64(Nanosecond))                                   |
|               |   Projection: timestamp, alias=b                                                      |
|               |     Projection: TimestampNanosecond(1668597032907296503, Some("+00:00")) AS timestamp |
|               |       EmptyRelation                                                                   |
| physical_plan | ProjectionExec: expr=[CAST(timestamp@0 AS Time64(Nanosecond)) as b.timestamp]         |
|               |   ProjectionExec: expr=[timestamp@0 as timestamp]                                     |
|               |     ProjectionExec: expr=[1668597032907296503 as timestamp]                           |
|               |       EmptyExec: produce_one_row=true                                                 |
|               |                                                                                       |
+---------------+---------------------------------------------------------------------------------------+
2 rows in set. Query took 0.005 seconds.
❯

[alamb]

🎉 thanks for checking @Jefffrey