Hi,
According to SASI source code (3.11.0) it will always have priority over
regular secondary index:
https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/index/sasi/SASIIndex.java#L234
public long getEstimatedResultRows()
{
// this is temporary (until proper QueryPlan is integrated into
Cassandra)
// and allows us to priority SASI indexes if any in the query since they
// are going to be more efficient, to query and intersect, than
built-in indexes.
return Long.MIN_VALUE;
}
I see that index building progress is reported as a CompactionInfo task so you
should be able to monitor progress using ‘nodetool compactionstats’. Last
point, from the moment that SASI index is created it will be used over regular
index so I think you could drop the regular as soon as it is created it will
make no difference. It also means that you may miss results until it is fully
built.
Note that I may be wrong, I’m just reading sources as I’m working on a custom
index.
--
Jacques-Henri Berthemet
From: Vlad [mailto:qa23d-...@yahoo.com.INVALID]
Sent: mercredi 12 juillet 2017 08:56
To: User cassandra.apache.org <user@cassandra.apache.org>
Subject: SASI and secondary index simultaniously
Hi,
it's possible to create both regular secondary index and SASI on the same
column:
CREATE TABLE ks.tb (id int PRIMARY KEY, name text);
CREATE CUSTOM INDEX tb_name_idx_1 ON ks.tb (name) USING
'org.apache.cassandra.index.sasi.SASIIndex';
CREATE INDEX tb_name_idx ON ks.tb (name);
But which one is used for SELECT? Assuming we have regular index and would like
to migrate to SASI, can we first create SASI, than drop regular? And how can we
check then index build is completed?
Thanks.
