Perform this query when something doesn't exist in another table

This is a really tricky question to ask as its very hard to explain what I'm after. Here goes though!

SELECT
    Stock.*,
    REPLACE (Description, '&', '&') as Description,
    PRD1.RuleValue AS Price, 
    PRD2.RuleValue AS WasPrice,
    PRD2.RuleValue-PRD1.RuleValue AS Save
FROM 
    Stock INNER JOIN
    StockCategoryMemberList ON StockCategoryMemberList.Sku = Stock.Sku LEFT JOIN 
    PriceRuleDetail PRD1 ON PRD1.Sku = Stock.Sku
        AND PRD1.PriceRule = 'RG'
        AND PRD1.Quantity = 1 LEFT JOIN
    PriceRuleDetail PRD2 ON PRD2.Sku = Stock.Sku
        AND PRD2.PriceRule = 'RRP'
        AND PRD2.Quantity = 1
WHERE StockCategoryMemberList.CategoryCode = 'FIRE'
AND Stock.GeneralStkStatus < 3
ORDER BY StockCategoryMemberList.Order ASC

This query works fine and produces all the correct data. I also have another table though called "StockMatrixDetail". I would like to remove any SKUs from the above query when the Sku exists in the StockMatrixDetail.Sku column. How can I mend this above query开发者_StackOverflow中文版 to include that???

So, the pseudo question is basically:

Perform the above query, but don't include any Skus that are in the StockMatrixDetail table, in the Column Sku.

Any help with this would be appreciated.

Kind Regards,

Andy

I've always done this via a NOT EXISTS clause...extremely fast, even more so if StockMatrixDetail.Sku is indexed...it doesn't even hit the table.

SELECT
    Stock.*,
    REPLACE (Description, '&', '&') as Description,
    PRD1.RuleValue AS Price, 
    PRD2.RuleValue AS WasPrice,
    PRD2.RuleValue-PRD1.RuleValue AS Save
FROM 
    Stock INNER JOIN
    StockCategoryMemberList ON StockCategoryMemberList.Sku = Stock.Sku LEFT JOIN 
    PriceRuleDetail PRD1 ON PRD1.Sku = Stock.Sku
        AND PRD1.PriceRule = 'RG'
        AND PRD1.Quantity = 1 LEFT JOIN
    PriceRuleDetail PRD2 ON PRD2.Sku = Stock.Sku
        AND PRD2.PriceRule = 'RRP'
        AND PRD2.Quantity = 1
WHERE StockCategoryMemberList.CategoryCode = 'FIRE'
AND NOT EXISTS (SELECT 1
                  FROM StockMatrixDetail smd
                  WHERE smd.Sku = Stock.Sku)
AND Stock.GeneralStkStatus < 3
ORDER BY StockCategoryMemberList.Order ASC