Question

I have two tables:

OutputPackages (master)

|PackageID|

OutputItems (detail)

|ItemID|PackageID|

OutputItems has an index called ‘idxPackage’ set on the PackageID column. ItemID is set to auto increment.

Here’s the code I’m using to insert masters/details into these tables:

//fill packages table
for i := 1 to 10 do
begin
  Package := TfPackage(dlgSummary.fcPackageForms.Forms[i]);

if Package.PackageLoaded then
begin
  with tblOutputPackages do
  begin
    Insert;
    FieldByName('PackageID').AsInteger := Package.ourNum;
    FieldByName('Description').AsString := Package.Title;
    FieldByName('Total').AsCurrency := Package.Total;
    Post;
  end;

  //fill items table
  for ii := 1 to 10 do
  begin
    Item := TfPackagedItemEdit(Package.fc.Forms[ii]);
    if Item.Activated then
    begin
      with tblOutputItems do
      begin
        Append;
        FieldByName('PackageID').AsInteger := Package.ourNum;
        FieldByName('Description').AsString := Item.Description;
        FieldByName('Comment').AsString := Item.Comment;
        FieldByName('Price').AsCurrency := Item.Price;
        Post; //this causes the primary key exception
      end;
    end;
  end;
end;

This works fine as long as I don’t mess with the MasterSource/MasterFields properties in the IDE. But once I set it, and run this code I get an error that says I’ve got a duplicate primary key ‘ItemID’.

I’m not sure what’s going on – this is my first foray into master/detail, so something may be setup wrong. I’m using ComponentAce’s Absolute Database for this project.

How can I get this to insert properly?

Update

Ok, I removed the primary key restraint in my db, and I see that for some reason, the autoincrement feature of the OutputItems table isn’t working like I expected. Here’s how the OutputItems table looks after running the above code:

ItemID|PackageID|
1     |1        |
1     |1        |
2     |2        |
2     |2        |

I still don’t see why all the ItemID values aren’t unique…. Any ideas?

Answer 1

Does using insert rather than append on the items table behave any differently? My guess here is that the append on the detail “sees” an empty dataset, so the auto-increment logic starts at one, the next record two, etc even though those values have already been assigned… just to a different master record.

One solution I used in the past was to create a new table named UniqueNums that persisted the next available record id number that I was going to use. As I used a number, I would lock that table, increment the value and write it back then unlock and use. This might get you around the specific issue you are having.