How to link selected grid rows to counter in different table?

Hi,
I had a quick look at your project and, unless I'm missing something, I don't think you need to make it as complicated as you are doing.
Specifically, why do you need a separate table just for the 'editcounter' when it could simply go on the 'linkitems' table.
Have a look at the attachment.
Regards,
Derek.

In that case, simply use a 'header' table (with the 'counter') and then use another table to hold all the related line items.
Please see attached (I used one of my own templates as it was quicker to demonstrate but everything can be applied to your project / layout).
One other suggestion is to use just a single form to maintain your reference tables ('clients' and 'items'). In bigger projects where you might have many such reference tables or if your current project starts to grow,  it can be a big time-saver when developing it and your program will load faster.
Derek.

Hi,
This is because the original requirement was for a job (jobheaders) that contained many items (joblines) and each job line could be for a different client.
What you are asking about is a job (jobheaders) that contains many items (joblines) but every job line is for the same client.
In this case, you can
1.  remove the relationship between client and joblines
2.  create a relationship between client and jobheaders
3.  adjust the tablegrids
4.  adjust Form2 and Form3
I believe these changes should give you the sort of thing you are wanting (see attachment).
It's okay if it's easier to post messages in your own language - most of us use 'google translate' anyway.
Regards,
Derek.

Hi,
I suspect from your screenshot that you are using a spreadsheet and although it might look how you want to see it (because you have removed the repeated data) if you ever need to re-sort your spreadsheet, you will encounter problems.
With a relational database (such as sqlite which is the default database used by MVD) data is typically presented in two or more tablegrids to avoid repeated data being displayed.  Putting all the data in a single tablegrid can be done but will result in certain pieces of information being repeated (ie Order No, Customer etc).
Have a look at the attachment for how it works.
Derek.