Luis E Fernandez created CASSANDRA-18987:
--------------------------------------------
Summary: Using counter column type in Accord transactions leads to
Atomicity / Consistency violations
Key: CASSANDRA-18987
URL: https://issues.apache.org/jira/browse/CASSANDRA-18987
Project: Cassandra
Issue Type: Bug
Reporter: Luis E Fernandez
*System configuration and information:*
Single node Cassandra with Accord transactions enabled running on docker
Built from commit:
[a7cd114435704b988c81f47ef53d0bfd6441f38b|https://github.com/apache/cassandra/commit/a7cd114435704b988c81f47ef53d0bfd6441f38b]
CQLSH: [cqlsh 6.2.0 | Cassandra 5.0-alpha2-SNAPSHOT | CQL spec 3.4.7 | Native
protocol v5]
*Steps to reproduce in CQLSH:*
{code:java}
CREATE KEYSPACE accord WITH replication = {'class': 'SimpleStrategy',
'replication_factor': '1'} AND durable_writes = true;{code}
{code:java}
CREATE TABLE accord.accounts (
partition text,
account_id int,
balance counter,
PRIMARY KEY (partition, account_id)
) WITH CLUSTERING ORDER BY (account_id ASC);
{code}
{code:java}
BEGIN TRANSACTION
UPDATE accord.accounts
SET balance += 100
WHERE
partition = 'default'
AND account_id = 0;
UPDATE accord.accounts
SET balance += 100
WHERE
partition = 'default'
AND account_id =1;
COMMIT TRANSACTION;{code}
bug happens after executing the following statement:
Based on [Cassandra
documentation|https://cassandra.apache.org/doc/trunk/cassandra/developing/cql/types.html#counters]
regarding the use of counters, I expect the following results:
Transaction A: subtract 10 from the balance of account 1 (total ending balance
of 90) and add 10 to the balance of account 0 (total ending balance of 110)
{*}Bug A{*}: Neither account's balance is updated and the state of the rows is
left unchanged
Transaction B: subtract 10 from the balance of account 1 (total ending balance
of 90) and add 10 to the balance of a new account 2 (total ending balance of 10)
{*}Bug B{*}: Only the new account 2 is created. The balance of account 1 is
left unchanged
{code:java}
/* Transaction A */
BEGIN TRANSACTION
UPDATE accord.accounts
SET balance -= 10
WHERE
partition = 'default'
AND account_id = 1;
UPDATE accord.accounts
SET balance += 10
WHERE
partition = 'default'
AND account_id = 0;
COMMIT TRANSACTION;{code}
{code:java}
/* Transaction B */
BEGIN TRANSACTION
UPDATE accord.accounts
SET balance -= 10
WHERE
partition = 'default'
AND account_id = 1;
UPDATE accord.accounts
SET balance += 10
WHERE
partition = 'default'
AND account_id = 2;
COMMIT TRANSACTION;{code}
Bug / Error:
======================================================================
The result of performing a table read after executing each buggy transaction is:
{code:java}
/* Transaction / Bug A */
partition | account_id | balance
-----------+------------+---------
default | 0 | 100
default | 1 | 100{code}
{code:java}
/* Transaction / Bug B */
partition | account_id | balance
-----------+------------+---------
default | 0 | 100
default | 1 | 100
default | 2 | 10 {code}
Note that performing the above statements without transaction blocks works as
expected.
{color:#172b4d}This was found while testing Accord transactions with
[~henrik.ingo] and team.{color}
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
