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https://issues.apache.org/jira/browse/CASSANDRA-14825?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16924124#comment-16924124
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Benedict commented on CASSANDRA-14825:
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There is a legitimate case to be made to support both approaches, in my opinion.

{{DESCRIBE}}'s main advantage, to my mind, is that it could support versioning 
of CQL grammar, so that you can ask for a string compatible with a given CQL 
version. This is difficult to do cleanly with a virtual table.

The presented factors in its favour don't seem relevant to me, and please try 
to avoid characterising others' disagreement with your points as 
misunderstanding or ignoring them:
 # {{cqlsh}} having it already does not seem particularly important, and should 
not bind our future decisions. It is a single tool, even if it is bundled.
 # Virtual tables are also very capable of surfacing the necessary information 
to produce dependent types, for instance as a collection column of the names of 
those type.

Further to this second point, virtual tables permit surfacing a whole lot more 
information in a structured _searchable_ manner.  Want to find which tables use 
a given type?  Search on that collection column.

>From a pure UX, personal preference perspective, I can say that I hate 
>features like {{DESCRIBE}} because I have to go and google the manual.  With a 
>virtual table interface, I just {{SELECT}} and progressively narrow my 
>criteria with {{WHERE}} clauses. I preferred this approach in SQL Server than 
>I do today's {{DESCRIBE}} in {{cqlsh}}.

So, I can see a case for both.  But if I had to choose, I would prefer virtual 
tables, and I haven't seen an argument that unequivocally seals the deal one 
way or the other.

> 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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