pgsql: pg_dump: allow multiple rows per insert

pg_dump: allow multiple rows per insert

This is useful to speed up loading data in a different database engine.

Authors: Surafel Temesgen and David Rowley.  Lightly edited by Álvaro.
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/CALAY4q9kumSdnRBzvRJvSRf2+BH20YmSvzqOkvwpEmodD-xv6g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7e413a0f82c8f8e9abb3981839191414de3aae08

Modified Files
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doc/src/sgml/ref/pg_dump.sgml    |  38 +++++---
src/bin/pg_dump/pg_backup.h      |   2 +-
src/bin/pg_dump/pg_dump.c        | 192 +++++++++++++++++++++++++++------------
src/bin/pg_dump/t/001_basic.pl   |   4 +-
src/bin/pg_dump/t/002_pg_dump.pl |  34 ++++++-
5 files changed, 193 insertions(+), 77 deletions(-)