[jira] [Updated] (DRILL-1689) Drill could not query a repeated map, and get all the values of one field into an array.

["Jacques Nadeau (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/DRILL-1689?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Jacques Nadeau updated DRILL-1689:
----------------------------------
    Issue Type: New Feature  (was: Bug)

> Drill could not query a repeated map, and get all the values of one field into an array. 
> -----------------------------------------------------------------------------------------
>
>                 Key: DRILL-1689
>                 URL: https://issues.apache.org/jira/browse/DRILL-1689
>             Project: Apache Drill
>          Issue Type: New Feature
>            Reporter: Jinfeng Ni
>             Fix For: Future
>
>
> Suppose we have the following JSON data:
> {code}
> {
>     "uid" : 1,
>     "events" : [
>         { "evnt_id":"e1", "campaign_id":"c1", "event_name":"e1_name", "event_time":1000000},
>         { "evnt_id":"e2", "campaign_id":"c1", "event_name":"e2_name", "event_time":2000000},
>         { "evnt_id":"e3", "campaign_id":"c1", "event_name":"e3_name", "event_time":3000000},
>         { "evnt_id":"e4", "campaign_id":"c1", "event_name":"e4_name", "event_time":4000000},
>         { "evnt_id":"e5", "campaign_id":"c2", "event_name":"e5_name", "event_time":5000000},
>         { "evnt_id":"e6", "campaign_id":"c1", "event_name":"e6_name", "event_time":6000000},
>         { "evnt_id":"e7", "campaign_id":"c1", "event_name":"e7_name", "event_time":7000000},
>         { "evnt_id":"e8", "campaign_id":"c2", "event_name":"e8_name", "event_time":8000000},
>         { "evnt_id":"e9", "campaign_id":"c2", "event_name":"e9_name", "event_time":9000000}
>     ],
>    "transactions" : [
>         { "trans_id":"t1", "amount":100, "trans_time":7777777},
>         { "trans_id":"t2", "amount":100, "trans_time":8888888}
>     ]
> }
> {code}
> "transactions" is repeated map.  We could return a field "trans_id" in i-th map in this repeated map. 
> {code}
> select t.transactions[1].trans_id from dfs.`/Users/jni/work/data/json/single-user-transactions.json` t;
> +------------+
> |   EXPR$0   |
> +------------+
> | t2         |
> +------------+
> {code}
> However, if we want to get  field "trans_id" from "ALL" the maps in this array, Drill will fail with exception:
> {code}
> select t.transactions.trans_id from dfs.`/Users/jni/work/data/json/single-user-transactions.json` t;
> Query failed: Failure while running fragment., org.apache.drill.exec.vector.complex.RepeatedMapVector cannot be cast to org.apache.drill.exec.vector.complex.MapVector [ 1317f855-b33a-4023-9164-3f22e7e8f1bf on 10.250.0.112:31013 ]
> {code}
> For the above query, SchemaPath "t.transactions.trans_id" should return an array of "trans_id", i.e ["t1", "t2"].



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)