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https://issues.apache.org/jira/browse/CASSANDRA-13547?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16066298#comment-16066298
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ZhaoYang commented on CASSANDRA-13547:
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Just my opinion
1. Missing Update.
if we force user to SELECT a restricted column in View, it will work. May have
some compatibility issue since users can do it before patching.
And it will cost extra space to store already know value from
ViewMetadata.selection.whereClause
By changing the filtering logic to check if there is restricted columns in
View, and generate corresponding view-updates will save some spaces on view
tables.
| With this we can also make sure that ALTER TABLE does not drop a column that
is used in view.
by checking ViewMetadata, this could also be prevented.
> 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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