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https://issues.apache.org/jira/browse/CASSANDRA-14825?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16923531#comment-16923531
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Robert Stupp commented on CASSANDRA-14825:
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Sorry for being very late to the ticket here.
The benefit of {{DESCRIBE}} over {{SELECT}} is that {{DESCRIBE}} can/could emit
a complete DDL script - e.g. a script like one that lands as the {{schema.cql}}
file in a snapshot, with all the dropped-columns. This is particularly
important, when you want to get the _really compatible_ schema for a table or
keyspace in backup/restore use cases or if you intend to move some sstables to
another cluster. User could for example issue a {{DESCRIBE
SCHEMA/KEYSPACE/TABLE foobar WITH INTERNALS}} and would get a complete script
that not just contains the keyspace + table definitions including the dropped
columns but also UDTs, UDFs, UDAs.
> Expose table schema for drivers
> -------------------------------
>
> Key: CASSANDRA-14825
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14825
> Project: Cassandra
> Issue Type: Improvement
> Components: Legacy/CQL
> Reporter: Chris Lohfink
> Assignee: Chris Lohfink
> Priority: Normal
> Labels: pull-request-available
> Time Spent: 1h 50m
> Remaining Estimate: 0h
>
> Currently the drivers recreate the CQL for the tables by putting together the
> system table values. This is very difficult to keep up to date and buggy
> enough that its only even supported in Java and Python drivers. Cassandra
> already has some limited output available for snapshots that we could provide
> in a virtual table or new query that the drivers can fetch. This can greatly
> reduce the complexity of drivers while also reducing bugs like
> CASSANDRA-14822 as the underlying schema and properties change.
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