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https://issues.apache.org/jira/browse/CASSANDRA-7378?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14030430#comment-14030430
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Robert Stupp commented on CASSANDRA-7378:
-----------------------------------------
It sound very simple - but in fact it isn't. The Java driver for example holds
a Map of _pstmt id_ to _pstmt_. The pstmt itself consists of the fields
{{query}}, {{queryKeyspace}}, {{routingKey}}, {{consistency}},
{{serialConsistency}}, {{traceQuery}}, {{retryPolicy}}. These fields make the
prepared statement unique. If only one field changes, it is _another_ pstmt.
imo it cannot be the protocol's or driver's responsibility to optimize for this
(compare with JDBC drivers - they don't do that either). And you should not
make any assumptions how the _pstmt id_ is calculated - the algorithm may
change due to C* internals.
> Protocol: Autoprepare flag for QUERY and BATCH requests
> -------------------------------------------------------
>
> Key: CASSANDRA-7378
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7378
> Project: Cassandra
> Issue Type: Improvement
> Components: API
> Reporter: Jorge Bay
> Priority: Minor
>
> Currently the flow for executing a prepared statement in the native protocol
> is:
> - PREPARE request
> - prepared response (queryid)
> - EXECUTE request (using queryid)
> - RESULT response
> - or UNPREPARED error response
> As is today, it is the responsibility of the driver or client to maintain the
> query id and to send a EXECUTE message using this query id and to expect for
> UNPREPARED error response in case the query got evicted or the node was
> restarted.
> With the following implications:
> - Before making a EXECUTE request, there is no way to know if it got evicted.
> - Before sending a PREPARE request, there is no way to know if that query has
> been already prepared on that host (by another connection), .
> - There isn't anything else the client can do with the prepared id (no much
> use from the client perspective).
> It would be nice to have a flag in the QUERY and BATCH requests that when
> set, the Cassandra node will prepare (if not already prepared) and execute
> the prepared query. This way we could save a few extra roundtrips and make
> the protocol flow for prepared statements a little more simple.
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