Custom SQL Stored Procedure Best Practices Analyzer - SQL Cop, Maybe?

Recently, I moved to Seattle as a Data Architect for a product our company was developing. I also started taking up most of the DBX roles in that project.

Though our architecture is predominantly CRUD based and we have our in-house CRUD proc generator, some business logic invariably seeps into the SPs. And we had let it to the discretion of the developers on whether to do the processing at Data or the Business Layer. I thought it would make sense to keep a rudimentary check on what logic was going into the SP and make sure our developers don't misuse the liberty and continue to follow the guidelines defined.

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A Scenario to Ponder #16

During my school days, I used to play this game that I would call as "word mutation". The problem statement gives the starting and ending 4-letter words.

The game is to find the path from the starting to the ending word by changing one alphabet at a time and ,of course, each of the words in the path should be a valid word.

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Solving Sudoku using SQL Server 2005 - Step by Step - Part #6

Implementation of RunSolveAlgorithm4:

This is the last post in this series. The previous algorithm is the last one that tries to solve the puzzle logically. This one will take the latest unsolved sudoku board that we get after running through the first three algorithms and use brute force to solve the puzzle. I am not going to reinvent the wheel here.

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Solving Sudoku using SQL Server 2005 - Step by Step - Part #5

Implementation of RunSolveAlgorithm3:

The last algorithm that we implemented was able to solve an easy puzzle. Now, lets take a hard one and see if the solution we have built till now in this series can solve it.

 EXEC SolveSudoku 
'030,001,000,,006,000,050,,500,000,983,,080,006,302,,000,050,000,,903,800,060,,714,000,009,,020,000,800,,000,400,030'

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Solving Sudoku using SQL Server 2005 - Step by Step - Part #4

Implementation of RunSolveAlgorithm2:

We implemented RunSolveAlgorithm1 in previous post of this series . The next algorithm is the implementation of Solve Method A from sudoku solver.

In this algorithm, we check all the cells (having mutiple values) in each row and see if a particular value occurs only once in that row. Then update that as the solution for the cell having that value. We do the similar check for column and the 3X3 block.

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Solving Sudoku using SQL Server 2005 - Step by Step - Part #3

Implementation of RunSolveAlgorithm1:

In the previous post of this series, we created the procedure stub for each algorithm. This post will implement RunSolveAlgorithm1.

The first algorithm will do the primary clean up on the solution board. It will implement the basic rules of Sudoku. The rule is that a number cannot appear in a cell if it already appears in any other cell in the same row or column or the block in the sudoku board. It will remove those numbers from the possible cadidate values of each cell in the solution board.

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Solving Sudoku using SQL Server 2005 - Step by Step - Part #2

In the first part of this series, we created the base objects needed to work on our solution. Now, there are two parts to building the solution:

• The core algorithms that will solve the puzzle for us
• The surrounding objects that will facilitate the solve and execute the core algorithms

The core algorithms are the crux of this whole exercise. Each of these algorithm will ideally take the unsolved sudoku board and try to fill as many cells as possible using the logic implemented in the specific alogorithm.

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