pgsql: Avoid sending prepare multiple times while decoding.

Avoid sending prepare multiple times while decoding.

We send the prepare for the concurrently aborted xacts so that later when
rollback prepared is decoded and sent, the downstream should be able to
rollback such a xact. For 'streaming' case (when we send changes for
in-progress transactions), we were sending prepare twice when concurrent
abort was detected.

Author: Peter Smith
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/f82133c6-6055-b400-7922-97dae9f2b50b@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f25a4584c6f56f3407f8f8734c78f2a87e4b77e8

Modified Files
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src/backend/replication/logical/reorderbuffer.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)