Re: JDBC and positioned updates

> we cannot achieve positioned updates using the JDBC implementation

This is "functional requirement"

> All of these parameters depends on what table we're going through

Those a "non-functional requirements" (see [1]).
You'd better collect NFRs *before* you finalize design and write the code.

>Our main problem is

Suppose you somehow achieved "positional updates". What if it turns
out to be super-slow? Believe me, there are good reasons for
"positional updates" to be super slow.
You would have to rewrite the whole thing from scratch to make it fast.

This is why I do not want to help you to shoot into your own foot.

Anyway, pull requests are welcome.

[1]: https://en.wikipedia.org/wiki/Non-functional_requirement

Vladimir