[Interest] Storing complex SQL relations with Qt
knut.krause at lagom.de
Thu Dec 12 07:57:50 CET 2013
my application uses sqlite for its data and I modeled some complex relations
for customers, appointments and so on.
Now I want to edit such a relation using a custom dialog where the
appointments go to a list and some other stuff to a table (all are
The problem is: How do I insert the data depending on other things? Let's say
an appointment needs a customer. I insert the new customer data and the
appointments and when I click on submit I'd have to do something like
1. insert customer (I think with primary key autoincrement I can simply do
2. retrieve the inserted customers ID. Can I use the models query() to get
lastInsertId()? Is this save?
3. Set this ID to all models that depends on customer (by hand?) and submit
them as well
Is this approach safe? I mean AFAIK there are no transactions involved and
what happens for example if I insert the customer and then my application
crashes leaving my database in an inconsistent state?
Would be nice if someone could explain how I'm supposed to do this.
More information about the Interest