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https://issues.apache.org/jira/browse/CASSANDRA-13547?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16040527#comment-16040527
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Krishna Dattu Koneru commented on CASSANDRA-13547:
--------------------------------------------------

I have uploaded a patch (with unittest) for problem 1 in above comment @ 
https://github.com/apache/cassandra/compare/cassandra-3.11...krishna-koneru:cassandra-3.11-13547

below problem addressed by this patch  (from the description)
{code}
cqlsh> UPDATE test.table1 SET enabled = TRUE WHERE id = 1 AND name = 'One';
cqlsh> SELECT * FROM test.table1;

 id | name | enabled | foo
----+------+---------+-----
  1 |  One |    True | Bar

(1 rows)
cqlsh> SELECT * FROM test.table1_mv1;

 name | id | foo
------+----+-----
{code}

This happens because view metadata does not have column "enabled" .
The decision "should this base table update, update view as well?" is made by 
looking at view metadata (among other things).
Due to this, some updates to base table do not result in updates to MV even if 
update qualifies .

This patch disallows usage of any non PK columns in WHERE clause if they are 
not in SELECT list.

Comments are appreciated !


> Filtered materialized views missing data
> ----------------------------------------
>
>                 Key: CASSANDRA-13547
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-13547
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Materialized Views
>         Environment: Official Cassandra 3.10 Docker image (ID 154b919bf8ce).
>            Reporter: Craig Nicholson
>            Assignee: Krishna Dattu Koneru
>            Priority: Blocker
>              Labels: materializedviews
>             Fix For: 3.11.x
>
>
> When creating a materialized view against a base table the materialized view 
> does not always reflect the correct data.
> Using the following test schema:
> {code:title=Schema|language=sql}
> DROP KEYSPACE IF EXISTS test;
> CREATE KEYSPACE test
>   WITH REPLICATION = { 
>    'class' : 'SimpleStrategy', 
>    'replication_factor' : 1 
>   };
> CREATE TABLE test.table1 (
>                 id int,
>                 name text,
>                 enabled boolean,
>                 foo text,
>                 PRIMARY KEY (id, name));
> CREATE MATERIALIZED VIEW test.table1_mv1 AS SELECT id, name, foo
>                 FROM test.table1
>                 WHERE id IS NOT NULL 
>                 AND name IS NOT NULL 
>                 AND enabled = TRUE
>                 PRIMARY KEY ((name), id);
> CREATE MATERIALIZED VIEW test.table1_mv2 AS SELECT id, name, foo, enabled
>                 FROM test.table1
>                 WHERE id IS NOT NULL 
>                 AND name IS NOT NULL 
>                 AND enabled = TRUE
>                 PRIMARY KEY ((name), id);
> {code}
> When I insert a row into the base table the materialized views are updated 
> appropriately. (+)
> {code:title=Insert row|language=sql}
> cqlsh> INSERT INTO test.table1 (id, name, enabled, foo) VALUES (1, 'One', 
> TRUE, 'Bar');
> cqlsh> SELECT * FROM test.table1;
>  id | name | enabled | foo
> ----+------+---------+-----
>   1 |  One |    True | Bar
> (1 rows)
> cqlsh> SELECT * FROM test.table1_mv1;
>  name | id | foo
> ------+----+-----
>   One |  1 | Bar
> (1 rows)
> cqlsh> SELECT * FROM test.table1_mv2;
>  name | id | enabled | foo
> ------+----+---------+-----
>   One |  1 |    True | Bar
> (1 rows)
> {code}
> Updating the record in the base table and setting enabled to FALSE will 
> filter the record from both materialized views. (+)
> {code:title=Disable the row|language=sql}
> cqlsh> UPDATE test.table1 SET enabled = FALSE WHERE id = 1 AND name = 'One';
> cqlsh> SELECT * FROM test.table1;
>  id | name | enabled | foo
> ----+------+---------+-----
>   1 |  One |   False | Bar
> (1 rows)
> cqlsh> SELECT * FROM test.table1_mv1;
>  name | id | foo
> ------+----+-----
> (0 rows)
> cqlsh> SELECT * FROM test.table1_mv2;
>  name | id | enabled | foo
> ------+----+---------+-----
> (0 rows)
> {code}
> However a further update to the base table setting enabled to TRUE should 
> include the record in both materialzed views, however only one view 
> (table1_mv2) gets updated. (-)
> It appears that only the view (table1_mv2) that returns the filtered column 
> (enabled) is updated. (-)
> Additionally columns that are not part of the partiion or clustering key are 
> not updated. You can see that the foo column has a null value in table1_mv2. 
> (-)
> {code:title=Enable the row|language=sql}
> cqlsh> UPDATE test.table1 SET enabled = TRUE WHERE id = 1 AND name = 'One';
> cqlsh> SELECT * FROM test.table1;
>  id | name | enabled | foo
> ----+------+---------+-----
>   1 |  One |    True | Bar
> (1 rows)
> cqlsh> SELECT * FROM test.table1_mv1;
>  name | id | foo
> ------+----+-----
> (0 rows)
> cqlsh> SELECT * FROM test.table1_mv2;
>  name | id | enabled | foo
> ------+----+---------+------
>   One |  1 |    True | null
> (1 rows)
> {code}



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