Many to many relation. How?

[Ralf Sander]

On 07.12.2004, at 17:36, Robert Brenstein wrote:

>>  > Also note that TIMESTAMP can be made as ULONG or ULLONG (8 byte) 
>> integer
>>>  value in the format
>>>
>>>  YYYYMMDD  HHMMSS
>>
>> OK, let's see, if I got it.
>>
>> I take the current date and time as string and add the recid as 
>> string and
>> store it into a LLong
>>
>> val("20041205143211"  + str(recid))
>> And this is really save? Or must the recid filled up with "0" s?
>>
>> val("20041205143211"  + "00000000000125")
>>
>> sorry, may be silly, but I and math....
>>
>> Thanks,
>> Ralf
>
> I think you are trying to make it more complicated than needed. It is 
> simpler to just use these fields separately.
>
> The timestamp field could be in yyymmddhhmmss format as suggested by 
> Ruslan
>
>   20041205143211
>
> or what the seconds function as supplied by the OS returns (a long 
> integer with seconds from some arbitrary point in the past). This 
> might not work, though, if your clients use different OS's since the 
> reference points vary somewhat between OS's if I am not mistaken.
>
> RecId field is maintained by Valentina and let it do it for you. You 
> just need to explicitly include it in SQL queries. Like
>
>    Select recId,* From ...
>
> If you want the outcome ordered by the entry time:
>
>    Select recId,* From ... Ordered by created_timestamp
>
> if you need your serial number to have a certain fixed numeric length, 
> you can create an extra field that contains recId+baseOffset (if you 
> want 5 digit numbers, baseOffset would be 10000 for example).
>
> In some of my programs (in particular when I need to collect data 
> through a few web views), I create a new record using recId as the 
> item identifier but leaving the "serial number" field empty until all 
> data is there and approved. Only then, I copy the recId (or 
> recId+baseOffset) into that field. This allows me to recycle records 
> with incomplete/abandoned entries without having to do any explicit 
> maintenance. Such a "serial number" field can also be used as a 
> traditional primary key should a need arise.
>
> Robert Brenstein

I think the serial number feature is an often needed one and it would 
be much easier, if Ruslan could add it as a new valentina feature :-)
Thanks,
Ralf