Oracle Universal Installer

Today we had a, what it seems, minor task of installing a Oracle Database instance on a remote server. But for some unknown reason we kept getting the following console output and then …nothing.

So we set onto the unknown searching throughout oracle website, forums, blogs, google …and got almost nothing.  Just a big load of crap concerning rare cases about remote installation failures etc.

After a lot of searching we found in the oracle database forums a post by a single person that said that for some reason Oracle Universal Installer fails to Launch while your installation drive has ~ 3TB empty space. Ours had ~2.6TB but still the launcher failed, so with a big more digging we found out that Oracle for some reason (probably cause 3TB didnt exist on the oracle database latest release)  didnt support >2TB drives.

Bottom Line we had to trick the system by creating an empty 1TB file using fsutil

And it worked!

Obviously ;-)

Pattern Based Sudoku Solving Algorithms (part A)

It is no secret that I love puzzles. Depending on the mood and period of my life, I find myself stuck with a certain kind of puzzles. Sudoku,among others, is naturally one of them and since I am fascinated with logic, it was bound, at some point, to check out what approach most programmers take in solving such a problem.

Most sudoku solving algorithms out there just “do” the job. Meaning they are mostly recursive and back-tracing solutions (like dancing links) rather than a more natural human approach.

Now whats the point in solving such a relatively simple problem without using such techniques. The point is that DLX techniques cannot produce a straight forward solution, I mean one that the filling sequence could fool someone that it wasn’t solved by a computer.

So I thought why not try to write some code based on how I think while solving a puzzle. Also Iam not allowing the algorithm to take notes and by notes I mean to pre-calculate every possible number that might correspond to each empty space.

My Solution so far is based on 3 Patterns and can solve most sudoku puzzles with a degree of difficult up to 7, 10 being the hardest.

There will be many more posts on this topic, in the near future…and probably some results concerning performance issues as well as a bit of code.

Here is a draft flowchart of the first Thinking Pattern
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