running a >> pkg update in Octave 5.1.0 on Windows 10, produced the following output for database-2.4.4.tar.gz:

command.cc: In member function 'octave_value command::copy_in_handler(const string&, const Cell&, const Cell&, bool, bool)':
command.cc:828:38: warning: format '%li' expects argument of type 'long int', but argument 2 has type 'octave_idx_type {aka long long int}' [-Wformat=]
                                  i, j);
                                      ^
command.cc:828:38: warning: format '%li' expects argument of type 'long int', but argument 3 has type 'octave_idx_type {aka long long int}' [-Wformat=]
var2bytea.cc: In function 'octave_value_list Fvar2bytea(const octave_value_list&, int)':
var2bytea.cc:101:74: warning: format '%li' expects argument of type 'long int', but argument 3 has type 'octave_idx_type {aka long long int}' [-Wformat=]
           error ("%s: could not save variable %li", fname.c_str (), i + 1);
                                                                     ~~~~~^
In file included from bytea2var.cc:28:0:
bytea2var.cc: In function 'octave_value_list Fbytea2var(const octave_value_list&, int)':
error-helpers.h:50:31: warning: format '%li' expects argument of type 'long int', but argument 3 has type 'octave_idx_type {aka long long int}' [-Wformat=]
             error (__VA_ARGS__); \
                               ^
bytea2var.cc:58:7: note: in expansion of macro 'CHECK_ERROR'
       CHECK_ERROR (m = args(i).uint8_array_value (), retval,
       ^~~~~~~~~~~
bytea2var.cc:139:68: warning: format '%li' expects argument of type 'long int', but argument 3 has type 'octave_idx_type {aka long long int}' [-Wformat=]
     error ("%s: could not load variable %li", fname.c_str (), i + 1);
                                                               ~~~~~^
For information about changes from previous versions of the database package, run 'news database'.

the package appeared to complete installation, but errors/warnings are a concern. Unknown if it would still occur in upcoming v6.0