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https://issues.apache.org/jira/browse/CASSANDRA-11288?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15175405#comment-15175405
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Sylvain Lebresne commented on CASSANDRA-11288:
----------------------------------------------

It would be easier to track/test if you were to share your reproduction script. 
I'll also note that 2.0 is no supported anymore, so we'll want to check if that 
still reproduce on 2.1.

> Schema agreement appears to be false positive following a DROP TABLE command
> ----------------------------------------------------------------------------
>
>                 Key: CASSANDRA-11288
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11288
>             Project: Cassandra
>          Issue Type: Bug
>         Environment: Cassandra 2.0.14.439 (DSE 4.6.7)
> 2 nodes OR 4 nodes
> Connecting with Datastax Java driver 2.1.8 OR 2.0.12 OR 2.1.4 OR 2.1.9 OR 
> 3.0.0
>            Reporter: Oliver Lockwood
>
> As part of a schema migration operation, our application is calling the 
> following operations on the Java driver consecutively:
> {noformat}
> session.execute("DROP TABLE table_name");
> session.execute("CREATE TABLE table_name (...)");
> {noformat}
> The second of these sometimes fails with a {{DriverException}} whose message 
> is "Table keyspace.table_name already exists".
> In the schema migration operation, there's 4 of these drop/create pairings 
> and, although it's random which exact one fails, we've never managed to get 
> further than the third operation in approximately 10 attempts - so there's a 
> reasonably high proportion of failure.
> I don't believe this is a driver issue because the driver is checking for 
> schema agreement (as per 
> https://github.com/datastax/java-driver/blob/2.1/driver-core/src/main/java/com/datastax/driver/core/ControlConnection.java#L701)
>  and we are seeing a log message to that effect.
> {noformat}
> c.d.d.c.ControlConnection - [] [] [] [] [] [] [] [] Checking for schema 
> agreement: versions are [02bce936-fddd-3bef-bb54-124d31bede57]
> {noformat}
> This log message appears in between our own logs which say "Executing 
> statement DROP TABLE..." and "Executing statement CREATE TABLE...", so we can 
> be reasonably sure this log message refers to the DROP operation being viewed 
> as "in agreement".
> Could this be a bug in the Cassandra server erroneously reporting that the 
> schemas are in agreement across the 2 nodes when, in fact, they are not?



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