SQL Server：存储过程挑战

Question

Here's the scenario: I have a table for SunflowerSeeds in SQL Server 2008.

CREATE TABLE [dbo].[SunflowerSeeds](
    [Color] [nvarchar](50) NULL,
    [SeedType] [nvarchar](50) NULL,
    [Price] float NULL
)

For simplicity, I haven't inserted long list of data.

Data insertion into the table looks like this:

Insert into [dbo].[SunflowerSeeds] (Color, SeedType, Price)
SELECT 'Yellow', 'Dwarf', 20
UNION ALL
SELECT 'Brown', 'Garden', 30
UNION ALL
SELECT 'Red', 'Garden', 35

Now I have been provided various matrices that could raise the price of the seed.

1. Polenless (YES/NO): If YES, raise the price by 10%
2. Height (> 13"): If YES, raise the price by 8%
3. Organic (YES/NO): If Yes, raise the price by 15%
4. Lifecycle (Annual- YES/NO): If Yes, raise the price by 12%

Each data insert row could have YES or NO value to each of the matrix listed above. I need to come up with a process to return the new price based on the Price of each seed in the SunFlowerseeds table and taking into a/c the combination of matrices.

For eg, if Yellow Dwarf is polenless, with height > 13”, Organic YES and having an annual life cycle then the new price has to be computed as

10% + 8%+15%+12% = 45% = 1+ 0.45= 1.45 

Then new price is: 1.45 * Original Price= 1.45*20 = 29

Likewise for rest of the combination.

I'm thinking of writing a SQL Server stored procedure, so that it could be called in my C# code later. The i/p parameters for the stored procedure will be Color and SeedType . With those two parameters, I could get the Price .

The challenge is how do I compute the new Price for each of the seed with a combination of applicable matrices - Polenless, height, Organic, LifeCycle. Can anyone point me a proper way of doing it. Please kindly help me out. TIA.

Answer 1

Suppose that combination of Color and SeedType in SunflowerSeeds is unique:

CREATE PROCEDURE UpdatePrice
    @Polenless BIT,
    @Height BIT,
    @Organic BIT,
    @Lifecycle BIT,
    @color NVARCHAR(50),
    @seedType NVARCHAR(50)

AS
BEGIN
   UPDATE SunflowerSeeds
   SET Price = Price +  
                        ((Price * 0.1) * @Polenless)+
                        ((Price * 0.08) * @Height)+
                        ((Price * 0.15) * @Organic)+
                        ((Price * 0.12) * @Lifecycle)
    WHERE Color = @color  AND SeedType = @seedType

END
GO

Also you may use a bitwise flag of type int instead of @Polenless, @Height, @Organic, @Lifecycle.