cassandra - Are PreparedStatements cached by CQL string? Does Datastax PreparedStatement retain statement ID? -


are statement caches on server , client side cached strictly string rendition of preparedstatement, or else? in other words, if 2 different preparedstatements created different means, end having same cql textual rendering, both have prepared (assuming same server)? if come different clients?

much less importantly... under conditions client able translate preparedstatement statement id, without consulting server?

(i'm coming oracle experience, if helps.)

if 2 different preparedstatements created different means, end having same cql textual rendering, both have prepared (assuming same server)? if come different clients?

executing same statement different clients
ran test on this, 2 clients execute identical prepared statement twice, cql statement cache in o.a.c.cql3.queryprocessor#preparedstatements ended storing 2 statements though string rendition identical meaning preparedstatements different clients cached.

executing same statement same client
duplicate statements single client not cached twice, can reused , don't have re-compiled, when client executes same prepared statement sends on statement id , parameters.


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