[
https://issues.apache.org/jira/browse/CASSANDRA-4386?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14877264#comment-14877264
]
Steven Warren edited comment on CASSANDRA-4386 at 9/19/15 6:44 PM:
-------------------------------------------------------------------
I'd like to make a case for raising the priority of this JIRA. I have a use
case which I don't think should be that unusual and where a secondary index IN
clause would be fantastic.
I have a set of wide rows ordered by an index (cluster key). I have a secondary
key on the primary column value.
If I want to look up by primary column value among the set of wide rows I have
to issue a query to each one:
select value from x where pk = :y and primary = :value
This is fine, the set of wide rows tends to be 1-100 rows so it's 1-100
parallel queries. However, without the in clause it's 1-100 parallel queries
per primary column value I want to specify. It would be much better to just
write:
select value from x where pk = :y and primary in :values
That gives me a fix number of queries to execute equal to the number of wide
rows in the set. This also should perform well since I'm specifying the
partition key and sending the parallel queries to the partition server for each
one.
was (Author: swarren):
I'd like to make a case for raising the priority of this JIRA. I have a use
case which I don't think should be that unusual and where a secondary index IN
clause would be fantastic.
I have a set of wide rows ordered by an index (cluster key). I have a secondary
key on the primary column value.
If I want to look up by primary column value among the set of wide rows I have
to issue a query to each one:
select value from x where pk = :y and primary = :value
This is fine, the set of wide rows tends to be 1-100 rows so it's 1-100
parallel queries. However, without the in clause it's 1-100 parallel queries
per primary column row I want to retrieve. It would be much better to just
write:
select value from x where pk = :y and primary in :values
That gives me a fix number of queries to execute equal to the number of wide
rows in the set. This also should perform well since I'm specifying the
partition key and sending the parallel queries to the partition server for each
one.
> Allow cql to use the IN syntax on secondary index values
> --------------------------------------------------------
>
> Key: CASSANDRA-4386
> URL: https://issues.apache.org/jira/browse/CASSANDRA-4386
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Jeremy Hanna
> Assignee: Benjamin Lerer
> Priority: Minor
> Labels: cql
>
> Currently CQL has a syntax for using IN to get a set of rows with a set of
> keys. This would also be very helpful for use with columns with secondary
> indexes on them. Such as:
> {code}
> select * from users where first_name in ('françois','frank');
> {code}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
