I dont think it is by design. Some one from dev please confirm.
That is because having several columns in a CSV and each column has a null
value, select * on such CSV returns null for each column. Why is it that
JSON is treated differently ?
0: jdbc:drill:schema=dfs.tmp> select * from `r1.csv`;
+---------------------------------------------------------------------------------+
| columns
|
+---------------------------------------------------------------------------------+
|
["null","null","null","null","null","null","null","null","null","null","null"]
|
+---------------------------------------------------------------------------------+
1 row selected (0.318 seconds)
On Thu, Nov 10, 2016 at 12:11 AM, rahul challapalli <
[email protected]> wrote:
> I think this is expected as drill does not differentiate between missing
> field and a field which has a null value for all records.
>
> On Wed, Nov 9, 2016 at 10:20 AM, Khurram Faraaz <[email protected]>
> wrote:
>
> > Is this by design or is this a bug ?
> >
> > On Tue, Nov 8, 2016 at 2:13 PM, Khurram Faraaz <[email protected]>
> > wrote:
> >
> > > Hi All,
> > >
> > > Drill 1.9.0 git commit ID : 83513daf
> > >
> > > Drill returns same result with or without `store.json.all_text_mode`=
> > true
> > >
> > > [root@cent01 null_eq_joins]# cat right_all_nulls.json
> > > {
> > > "intKey" : null,
> > > "bgintKey": null,
> > > "strKey": null,
> > > "boolKey": null,
> > > "fltKey": null,
> > > "dblKey": null,
> > > "timKey": null,
> > > "dtKey": null,
> > > "tmstmpKey": null,
> > > "intrvldyKey": null,
> > > "intrvlyrKey": null
> > > }
> > > [root@cent01 null_eq_joins]#
> > >
> > > Querying the above JSON file results in null as query result.
> > > - We should see each of the keys in the JSON as a column in query
> > result.
> > > - And in each column the value should be a null value.
> > > Current behavior does not look right.
> > >
> > > {noformat}
> > > 0: jdbc:drill:schema=dfs.tmp> select * from `right_all_nulls.json`;
> > > +-------+
> > > | * |
> > > +-------+
> > > | null |
> > > +-------+
> > > 1 row selected (0.313 seconds)
> > > {noformat}
> > >
> > > Thanks,
> > > Khurram
> > >
> >
>
