I make Invoices with Group items mixed with normal (non-group) items. I am having a problem controlling the order of how the items appear on the Invoice when viewed in QuickBooks.

I use the method where you do a SQL INSERT command for each InvoiceLine, setting the FQSaveToCache field to 1, and then insert the Invoice. If I first insert a normal item, then a Group item, and then a normal item, then when I view the Invoice the Group item appears at the bottom of the lineitem list.

I am assuming that the order in which you insert the InvoiceLines should be the order in which they appear on the Invoice. Is this a bug? or do I need to do something else to force the order of the lineitems?

The ItemGroups are going to appear last as they processed by the (FQSaveToCache) transaction batch last by QuickBooks. This is because QuickBooks needs to go out and create all the InvoiceLines for the group(s), and group inserts are more than just the header line that you are inserting.

You can write the Invoice, use

SP_LASTINSERTID invoice

to get the TxnID of the invoice you just inserted and then add new normal line items after the group by doing, for example:

INSERT INTO "InvoiceLine" ("TxnID", "InvoiceLineItemRefListID", "InvoiceLineDesc",
"InvoiceLineRate", "InvoiceLineAmount", "InvoiceLineSalesTaxCodeRefListID")
VALUES ('5CFE-1197770436', '250000-933272656', 'Test Add a Line',
1.00000, 1.00, '20000-999022286')

See: How do I invoice item groups?  for more.