While "public-inbox-extindex --gc" invocations try to ensure
proper ordering, it is still possible for users to change
the `inboxes' tables via sqlite3(1) or similar means. So
show a "missing://ibx_id=$ibx_id" placeholder to avoid undefined
variable warnings.
URLs such as "imaps://..." will eventually be supported as
eidx_keys, so having a URL-like "missing://" as a placeholder
probably makes sense.
my $r = $_;
$eidx_key_sth->execute($r->[0]);
my $eidx_key = $eidx_key_sth->fetchrow_array;
+ $eidx_key //= "missing://ibx_id=$r->[0]";
"$eidx_key:$r->[1]:".unpack('H*', $r->[2]);
} @$rows ];
}