Need help with adding calculated field or may be adding extra column?

Hi,
Looking at the screen shot in your attachment, I would use calculated fields to display the 'in', 'out' and 'stock in hand' balances per product for each supplier (please see attached as an example of how to create your calculated fields). 
I haven't added a calculated field for 'tra close' because I can't work out from your attachment what this is but the principle, in terms of indicating it with a calculated field, is the same as for the other calculated fields.
I have also added two calculated fields on your 'transactions' table to show 'quantity in' and 'quantity out' rather than just using one table field with an indicator as you are currently doing.  Moving forward, you might consider creating discrete fields ('quantity in', 'quantity out') as this is perhaps more user-friendly than having just one field ('quantity'_ and using an indicator ('is_inward').  But these are just suggestions.
Regards,
Derek.

Hi,
I'm not sure if I understand all your points correctly but hopefully the following will make sense.
1.
I was looking at your data schema and would suggest instead of using a flag (is_inward = yes), you could just use a positive quantity and for is_inward = no, just use a negative quantity. 
Personally I think this would be less confusing (and is one less thing for the user to input).
2.
The stock balance is already being calculated so Instead of 'is_open = no', just replace this with an automatic check whether 'stock balance = 0'.  You could also add a flag using a calculated field to show, for example if a job is 'not started', 'in progress' or 'finished' to make it even more obvious.
3.
With regard to your question about parent-child tablegrids, have a look at the attachment;  form1.tablegrid2 and form1.tablegrid3 are both 'child' tablegrids of form1.tablegrid1.  Click in any row of tablegrid1 to see the associated 'child' transactions.  I've chosen to split 'inwards' and 'outwards' transactions into two child tables but it's up to you how you best want to see the information.
4.
Cascade / delete is theoretically a good idea if you want to keep your data tidy.. However, if you have a lot of tables with relationships, you can end up deleting data that you might need without realising it. 
But more importantly, if your application is to be used commercially, there might be legal requirements (depending on your country) to maintain all data and not delete anything.
If you're considering using cascade / delete from a business process point of view because, for example, there is a product that you no longer use, it's perhaps a better idea to add a 'do not use' flag to the appropriate table so that it can be automatically excluded from any subsequent transactions..
5.  Concerning your point about multiple transactions on the same day, you might want to consider re-defining your transaction date from a field type of 'date' to a field type of 'date/time'.
.
The attached project hopefully clarifies some of the above points.  Also, perhaps it gives you some ideas of how your project might develop once you get more familiar with MVD.  As always with MVD there are lots of different ways to do things and this isn't to say that one way is correct and another way is incorrect - it's more just to show you options.
There is a (relatively) small script attached to the project but this is more to do with a) the 'look and feel' and b) to add some validation rather than the basic functionality which can be done using standard MVD.
If anything is not clear, just shout.
Derek.