Fear No SQL
For me, TRUNC is one of the handiest Date functions available. If you work with time-based data a lot you’ll frequently find a home for it in your queries. For example, find all objects that were modified yesterday: select * from all_objects where last_ddl_time >= trunc(sysdate)-1 and last_ddl_time < trunc(sysdate) TRUNC isn’t limited to just…
The 12-Coins is a classic balance puzzle where the goal is find a fake coin from one of 12 using only 3 trials on the balance scale. Furthermore, once you find the fake coin you should be able to determine if it is lighter or heavier than the real coins. The solution involves dividing the…
Several months ago I used the classic 8-Queens chess puzzle as an illustration of using a little bit of math to determine intractable problems. In that article I teased a code solution for the puzzle but never followed up… until now. There are 92 distinct solutions, including rotations and reflection duplicates. The package’s demo procedure…
My wife has a nutcracker collection. One of them includes a pair of cubes for use as a counter. One of the cubes has the digits 0,1,2,3,4,5 on the faces. The other cube has the digits 0,1,2,6,7,8. The 6 is invertible to be used as a 9, thus allowing for 7 digits on 6 faces.…