pgsql: pgbench: Add TAP tests to check consistency of data generated

pgbench: Add TAP tests to check consistency of data generated

The tables created by pgbench rely on a few assumptions for TPC-B, where
the "filler" attribute is used to comply with this benchmark's rules as
well as pgbencn historical behavior. The data generated for each table
uses this filler in a different way:
- pgbench_accounts uses it as a blank-padded empty string.
- pgbench_tellers and pgbench_branches use it as a NULL value.

There were no checks done about the consistency of the data initialized,
and this has showed up while discussing a patch that changes the logic
in charge of the client-side data generation (pgbench documents all that
already in its comments). This commit adds some checks on the data
generated for both the server-side and client-side logic.

Reviewed-by: Tristan Partin
Discussion: https://postgr.es/m/ZLik4oKnqRmVCM3t@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/29836df323d752d534deb7b922cd48f08132e044

Modified Files
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src/bin/pgbench/t/001_pgbench_with_server.pl | 35 ++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)