Got {aborted,{no_exists,pdpcontext}} with Mnesia

[Jan Chochol]

Your call to "mnesia:create_table" fails with
"{aborted,{bad_type,pdpcontext,disc_copies,nonode@REDACTED}}" (you are
not checking return value, so it is hard to spot).
For disc copies you need create schema first, so something like:

database_initialize() ->
    ok = mnesia:create_schema([node()]),
    ok = mnesia:start(),
    {atomic, ok} = mnesia:create_table(
pdpcontext, [{disc_copies, [node()]}, {attributes, record_info(fields,
pdpcontext)}]
),
   mnesia:stop().

Also "mnesia:create_schema/1" fails with something like
"{error,{_,{already_exists,_}}}", when schema already exists (you need
to count with it in code).

Regards,
Jan

On Thu, Jul 16, 2020 at 11:19 AM Dániel Szoboszlay
<dszoboszlay@REDACTED> wrote:
>
> The error suggests you're trying to read or write a table called pdpcontext which doesn't exist. Maybe you forgot to create it?
>
> Cheers,
> Daniel
>
> On Thu, 16 Jul 2020 at 10:24, Papa Tana <papa.tana101@REDACTED> wrote:
>>
>> Hi All,
>>
>> I want to use Mnesia for my application, but it returns "no_exists"
>>
>> According to the documentation:
>>
>> ==> no_exists: Tried to perform operation on non-existing (non-alive) item.
>>
>> $ dialyzer first.erl
>>   Checking whether the PLT c:/Users/Lova/.dialyzer_plt is up-to-date... yes
>>   Proceeding with analysis... done in 0m0.23s
>> done (passed successfully)
>>
>>
>> $ erl -sname myggsn@REDACTED
>> Eshell V11.0  (abort with ^G)
>>
>> (myggsn@REDACTED)1> c(first).
>> {ok,first}
>>
>> (myggsn@REDACTED)2> node().
>> myggsn@REDACTED
>>
>> (myggsn@REDACTED)3> mnesia:start().
>> ok
>>
>> (myggsn@REDACTED)4> first:database_initialize().
>> =INFO REPORT==== 16-Jul-2020::11:12:13.951000 ===
>>     application: mnesia
>>     exited: stopped
>>     type: temporary
>>
>> stopped
>>
>> (myggsn@REDACTED)5> first:start().
>> {aborted,{no_exists,pdpcontext}}
>>
>> Where am I wrong please?
>>
>> I send enclosed my first.erl
>>
>> Best Regards,