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https://issues.apache.org/jira/browse/CASSANDRA-6477?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14503936#comment-14503936
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Jack Krupansky commented on CASSANDRA-6477:
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Oracle has lots of options for the REFRESH clause of the CREATE MATERIALIZED
VIEW statement:
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_6002.htm
Notes on that syntax:
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_6002.htm#i2064161
Full MV syntax:
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_6002.htm
You can request that a materialized view be automatically refreshed when the
base tables are updated using the "REFRESH ON COMMIT" option. The update
transaction pauses while the views are updated - "Specify ON COMMIT to indicate
that a fast refresh is to occur whenever the database commits a transaction
that operates on a master table of the materialized view. This clause may
increase the time taken to complete the commit, because the database performs
the refresh operation as part of the commit process."
You can also refresh on time intervals, on demand, or no refresh ever.
Originally MV was known as SNAPSHOT - a one-time snapshot of a view of the base
tables/query.
Oracle has a FAST refresh, which depends on a MATERIALIZED VIEW LOG, which must
be created for the base table(s). Otherwise a COMPLETE refresh is required.
> Global indexes
> --------------
>
> Key: CASSANDRA-6477
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6477
> Project: Cassandra
> Issue Type: New Feature
> Components: API, Core
> Reporter: Jonathan Ellis
> Assignee: Carl Yeksigian
> Labels: cql
> Fix For: 3.0
>
>
> Local indexes are suitable for low-cardinality data, where spreading the
> index across the cluster is a Good Thing. However, for high-cardinality
> data, local indexes require querying most nodes in the cluster even if only a
> handful of rows is returned.
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