cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Marten Kenbeek (Jira)" <j...@apache.org>
Subject [jira] [Updated] (CASSANDRA-16784) Conditional update on super column table returns too many rows
Date Thu, 01 Jul 2021 15:53:00 GMT

     [ https://issues.apache.org/jira/browse/CASSANDRA-16784?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Marten Kenbeek updated CASSANDRA-16784:
---------------------------------------
    Description: 
We have a (dense) supercolumn table that we're trying to upgrade from 2.2 to 3.x. On this
table we perform conditional updates on one of the values using a CQL query. In 2.2 this works
as expected: the query returns either a single-column row with {{true}}, or a two-column row
with {{false}} and the current value.

In 3.x this query is internally rewritten to work on a map, using a {{Maps.SetterByKey}} operation.
The update itself is applied correctly, but when the condition fails and the update is not
applied, the query returns all values in the supercolumn/map instead of just the value of
the subcolumn/key from the where clause.

In particular, since it returns _just_ the values, and not the keys/mapping, there's no way
to know which of the values is the value of the row we're trying to update.

 
{code:java}
– Super column table (created through Thrift)
 CREATE TABLE store.shopping_items (
 key text,
 column1 text,
 column2 text,
 "" map<text, text>,
 value text,
 PRIMARY KEY (key, column1, column2)
 ) WITH COMPACT STORAGE;
– Create some data
 cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'id', '1');
 cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'color', 'blue');
– This query returns multiple rows
 cqlsh:store> UPDATE shopping_items SET value ='2' WHERE key ='item1' AND column1 = 'default'
AND column2 = 'id' IF value = null;
[applied] | value
 ----------+-----------
 False | 'blue'
 False | '1'
{code}
 

See the attached patch for a test that succeeds on 2.2, but fails with the described behavior
on 3.0 and on the latest 3.11. 

  was:
We have a (dense) supercolumn table that we're trying to upgrade from 2.2 to 3.x. On this
table we perform conditional updates on one of the values using a CQL query. In 2.2 this works
as expected: the query returns either a single-column row with {{true}}, or a two-column row
with {{false}} and the current value.

In 3.x this query is internally rewritten to work on a map, using a {{Maps.SetterByKey}} operation.
The update itself is applied correctly, but when the condition fails and the update is not
applied, the query returns all values in the supercolumn/map instead of just the value of
the subcolumn/key from the where clause.

In particular, since it returns _just_ the values, and not the keys/mapping, there's no way
to know which of the values is the value of the row we're trying to update.
-- Super column table (created through Thrift)
CREATE TABLE store.shopping_items (
    key text,
    column1 text,
    column2 text,
    "" map<text, text>,
    value text,
    PRIMARY KEY (key, column1, column2)
) WITH COMPACT STORAGE;

-- Create some data
cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'id', '1');
cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'color', 'blue');

-- This query returns multiple rows
cqlsh:store> UPDATE shopping_items SET value ='2' WHERE key ='item1' AND column1 = 'default'
AND column2 = 'id' IF value = null;

 [applied] | value
-----------+------------
     False |     'blue'
     False |        '1'
See the attached patch for a test that succeeds on 2.2, but fails with the described behavior
on 3.0 and on the latest 3.11. 


> Conditional update on super column table returns too many rows
> --------------------------------------------------------------
>
>                 Key: CASSANDRA-16784
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-16784
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Feature/Lightweight Transactions
>            Reporter: Marten Kenbeek
>            Priority: Normal
>         Attachments: dense_supercolumn_lwt_test.patch
>
>
> We have a (dense) supercolumn table that we're trying to upgrade from 2.2 to 3.x. On
this table we perform conditional updates on one of the values using a CQL query. In 2.2 this
works as expected: the query returns either a single-column row with {{true}}, or a two-column
row with {{false}} and the current value.
> In 3.x this query is internally rewritten to work on a map, using a {{Maps.SetterByKey}}
operation. The update itself is applied correctly, but when the condition fails and the update
is not applied, the query returns all values in the supercolumn/map instead of just the value
of the subcolumn/key from the where clause.
> In particular, since it returns _just_ the values, and not the keys/mapping, there's
no way to know which of the values is the value of the row we're trying to update.
>  
> {code:java}
> – Super column table (created through Thrift)
>  CREATE TABLE store.shopping_items (
>  key text,
>  column1 text,
>  column2 text,
>  "" map<text, text>,
>  value text,
>  PRIMARY KEY (key, column1, column2)
>  ) WITH COMPACT STORAGE;
> – Create some data
>  cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'id', '1');
>  cqlsh:store> INSERT INTO shopping_items (key, column1, column2, value) VALUES ('item1',
'default', 'color', 'blue');
> – This query returns multiple rows
>  cqlsh:store> UPDATE shopping_items SET value ='2' WHERE key ='item1' AND column1
= 'default' AND column2 = 'id' IF value = null;
> [applied] | value
>  ----------+-----------
>  False | 'blue'
>  False | '1'
> {code}
>  
> See the attached patch for a test that succeeds on 2.2, but fails with the described
behavior on 3.0 and on the latest 3.11. 



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org


Mime
View raw message