pgsql: Slightly simplify nbtree split point choice loop.

Slightly simplify nbtree split point choice loop. Spotted during post-commit review of the nbtree deduplication commit (commit 0d861bbb). Branch -- master Details --- https://git.postgresql.org/pg/commitdiff/f0ca378d4c139eda99ef14998115c1674dac3fc5 Modified Files -- src/back

pgsql: Disable silently generation of manifests with servers <= 12 in p

Disable silently generation of manifests with servers <= 12 in pg_basebackup Since 0d8c9c1, pg_basebackup would generate an error if connected to a backend version older than 12 where backup manifests are not supported. Avoiding this error is possible by using the --no-manifest option. This error

pgsql: Fix the usage of parallel and full options of vacuum command.

Fix the usage of parallel and full options of vacuum command. Earlier we were inconsistent in allowing the usage of parallel and full options. Change it such that we disallow them only when they are combined in a way that we don't support. In passing, improve the comments in some of the existing