[jira] [Updated] (IMPALA-11824) View that cast column to the same type cannot be used

["Quanlong Huang (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-11824?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Quanlong Huang updated IMPALA-11824:
------------------------------------
    Description: 
I found this when debugging for another issue. For views that cast columns to the same types, any usage of it will failed with "Could not resolve column/field reference" error. Here's an example:
{code:sql}
create table t (id int) stored as textfile;
insert into t select 1;

create view v(id) as select cast(id as int) from t;
select * from v;
ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'

select id from v;
ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'

# Casting id to a different type works
create view v2(id) as select cast(id as tinyint) from t;
+----+
| id |
+----+
| 1  |
+----+

# Don't specifying the view column names also works
create view v3 as select cast(id as tinyint) from t;
+-----+
| _c0 |
+-----+
| 1   |
+-----+{code}
Note that it works if I create the view in Hive. Comparing the results of DESCRIBE FORMATTED, the difference is in the "View Expanded Text". In the Impala-created view, it's
{code:sql}
SELECT v.`_c0` AS id FROM (SELECT CAST(id AS INT) FROM `default`.t) v
{code}
In the Hive-created view, it's
{code:sql}
SELECT `id` AS `id` FROM (select `t`.`id` from `default`.`t`) `hive_view`
{code}

  was:
I found this when debugging for another issue. For views that cast columns to the same types, any usage of it will failed with "Could not resolve column/field reference" error. Here's an example:
{code:java}
create table t (id int) stored as textfile;
insert into t select 1;

create view v(id) as select cast(id as int) from t;
select * from v;
ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'

select id from v;
ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'

# Casting id to a different type works
create view v2(id) as select cast(id as tinyint) from t;
+----+
| id |
+----+
| 1  |
+----+

# Don't specifying the view column names also works
create view v3 as select cast(id as tinyint) from t;
+-----+
| _c0 |
+-----+
| 1   |
+-----+{code}


> View that cast column to the same type cannot be used
> -----------------------------------------------------
>
>                 Key: IMPALA-11824
>                 URL: https://issues.apache.org/jira/browse/IMPALA-11824
>             Project: IMPALA
>          Issue Type: Bug
>          Components: Frontend
>            Reporter: Quanlong Huang
>            Priority: Critical
>
> I found this when debugging for another issue. For views that cast columns to the same types, any usage of it will failed with "Could not resolve column/field reference" error. Here's an example:
> {code:sql}
> create table t (id int) stored as textfile;
> insert into t select 1;
> create view v(id) as select cast(id as int) from t;
> select * from v;
> ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'
> select id from v;
> ERROR: AnalysisException: Could not resolve column/field reference: 'v._c0'
> # Casting id to a different type works
> create view v2(id) as select cast(id as tinyint) from t;
> +----+
> | id |
> +----+
> | 1  |
> +----+
> # Don't specifying the view column names also works
> create view v3 as select cast(id as tinyint) from t;
> +-----+
> | _c0 |
> +-----+
> | 1   |
> +-----+{code}
> Note that it works if I create the view in Hive. Comparing the results of DESCRIBE FORMATTED, the difference is in the "View Expanded Text". In the Impala-created view, it's
> {code:sql}
> SELECT v.`_c0` AS id FROM (SELECT CAST(id AS INT) FROM `default`.t) v
> {code}
> In the Hive-created view, it's
> {code:sql}
> SELECT `id` AS `id` FROM (select `t`.`id` from `default`.`t`) `hive_view`
> {code}



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