Comments on: Writing a Word Search puzzle solver in SQL

By: Patrick Barel

Patrick Barel — Wed, 20 Dec 2006 18:37:14 +0000

@Patrick Sinke. There is already a solution to solving sudoku puzzles: http://www.db-innovations.co.uk/sudoku.htm
I even created a, somewhat crude, front-end to this solution

By: Zeger Hendrikse

Zeger Hendrikse — Mon, 11 Dec 2006 09:11:55 +0000

Incredible, it reminds me of the “obfuscated C-code contest”, where one of the participants wrote the towers of Hanoi (recursive) using C pre-processor directives only.

Maybe it is time to start an obfuscated SQL-query contest too. On the other hand, this would be a boring contest, as we would know the winner in advance

By: Lucas Jellema

Lucas Jellema — Sat, 09 Dec 2006 09:36:04 +0000

Yes, that is a good one. Much neater.

By: anton

anton — Sat, 09 Dec 2006 01:00:18 +0000

And now I think about it, another solution for your “direction table” using the word_list type

, direction as
( select to_number column_value ) dir
from table( word_list( ‘-1′, ’0′, ’1′ ) )
)

Anton

By: anton

anton — Sat, 09 Dec 2006 00:49:51 +0000

The algoritm is very brilliant! And its simple at the same time:

from ( select *
from cells
, directions
) x
connect by

And the idea to use SQL to solve a puzzle like this is brilliant too, it has only one small drawback for real puzzles: it needs the “words” to search for

But the thing I like the best is using the table type for generating some rows with data: select … from table ( word_list( …

Anton

By: Lucas Jellema

Lucas Jellema — Fri, 08 Dec 2006 18:51:19 +0000

Anton,

As always you have improved way beyond my original – and apparently not only suboptimal but even faulty – code. Thanks for the improvements – it is faster and more robust.

I still pride myself in the core of the algoritm…

By: anton

anton — Fri, 08 Dec 2006 18:44:31 +0000

A brilliant post indeed. As an interested reader I did tried to understand everything. And offcourse I did tried to solve it the other way around, "find all paths from all cells and try to join those paths to the search words". On my computer runs the query from Lucas in about 25 seconds. A solution which "joins all paths from all cells" runs in less than one second!!. And it finds more solutions too. As I am a lazy author too, I did not bother to find the differences or whats causing it. Anton

Download the code here: puzzle.sql

By: Marco Gralike

Marco Gralike — Fri, 08 Dec 2006 17:10:47 +0000

Brilliant post and good fun, thanks.

By: Jeff Kemp

Jeff Kemp — Fri, 08 Dec 2006 00:31:09 +0000

How about a query to list all the letters that weren’t used – since most word search puzzles hide a final word or phrase in all the leftover spaces. Or is that another “exercise for the reader”?

By: Jasper

Jasper — Thu, 07 Dec 2006 11:22:37 +0000

Hahaha this is cracking me up, very nice