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https://issues.apache.org/jira/browse/CASSANDRA-14684?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16598764#comment-16598764
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Jeremy Hanna edited comment on CASSANDRA-14684 at 8/31/18 2:25 PM:
-------------------------------------------------------------------
It depends on the partitioner. For the default murmur3 partitioner, the range
is -2^63^ to +2^63^-1 which is Long.MIN_VALUE to Long.MAX_VALUE. So it should
work up to those boundaries. For the random partitioner which is an md5 based
hash, it's 0 to 2^127-1 but I doubt you're using that.
However reading through the code, even though the [minimum value set for
murmur3 is
Long.MIN_VALUE|https://github.com/apache/cassandra/blob/06209037ea56b5a2a49615a99f1542d6ea1b2947/src/java/org/apache/cassandra/dht/Murmur3Partitioner.java#L43],
we exclude that for [reasons described in the getToken()
method|https://github.com/apache/cassandra/blob/06209037ea56b5a2a49615a99f1542d6ea1b2947/src/java/org/apache/cassandra/dht/Murmur3Partitioner.java#L208-L213].
{code}
/**
* Generate the token of a key.
* Note that we need to ensure all generated token are strictly bigger than
MINIMUM.
* In particular we don't want MINIMUM to correspond to any key because the
range (MINIMUM, X] doesn't
* include MINIMUM but we use such range to select all data whose token is
smaller than X.
*/
{code}
So good point [~benedict], we should probably document that beyond the comment
in the code.
was (Author: jeromatron):
It depends on the partitioner. For the default murmur3 partitioner, the range
is -2^63^ to +2^63^-1 which is Long.MIN_VALUE to Long.MAX_VALUE. So it should
work up to those boundaries. For the random partitioner which is an md5 based
hash, it's 0 to 2^127-1 but I doubt you're using that.
However reading through the code, even though the [minimum value set for
murmur3 is
Long.MIN_VALUE|https://github.com/apache/cassandra/blob/06209037ea56b5a2a49615a99f1542d6ea1b2947/src/java/org/apache/cassandra/dht/Murmur3Partitioner.java#L43],
we exclude that for [reasons described in the getToken()
method|https://github.com/apache/cassandra/blob/06209037ea56b5a2a49615a99f1542d6ea1b2947/src/java/org/apache/cassandra/dht/Murmur3Partitioner.java#L208-L213].
{code}
/**
* Generate the token of a key.
* Note that we need to ensure all generated token are strictly bigger than
MINIMUM.
* In particular we don't want MINIMUM to correspond to any key because the
range (MINIMUM, X] doesn't
* include MINIMUM but we use such range to select all data whose token is
smaller than X.
*/
{code}
> Queries with a clause involving tokens and Long.MIN_VALUE include rows
> incorrectly
> ----------------------------------------------------------------------------------
>
> Key: CASSANDRA-14684
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14684
> Project: Cassandra
> Issue Type: Bug
> Reporter: George Boyle
> Priority: Major
>
> [cqlsh 5.0.1 | Cassandra 2.2.9 | CQL spec 3.3.1 | Native protocol v4]
> When running a CQL query where we filter on a token compared to
> -9223372036854775808 (the minimum value for a long), the filter appears to
> have no effect.
> For example:
> {code:java}
> SELECT token(user_id) FROM events WHERE token(user_id) = -9223372036854775808
> LIMIT 3;
> system.token(user_id)
> -----------------------
> -9223371814601747988
> -9223371814601747988
> -9223371814601747988
> {code}
> It doesn't matter whether `=`, `<`, `<=`, `>` or `>=` are used in the
> comparison, the results appear the same.
> In contrast, if using `Long.MIN_VALUE + 1`, it returns no results as
> expected:
> {code:java}
> SELECT token(user_id) FROM events WHERE token(user_id) <=
> -9223372036854775807 LIMIT 3;
> system.token(user_id)
> -----------------------
> (0 rows)
> {code}
>
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