Execute the following Microsoft SQL Server T-SQL script in SSMS Query Editor to perform inventory updates for specific date when a product exists:

IF EXISTS (SELECT 1 FROM Warehouse WHERE ProductID = 800)

UPDATE i SET DateOfPurchase = '20090420' -- YYYYMMDD

FROM Product.Inventory i

  INNER JOIN Product.SalesHistory AS s

    ON s.BarCode = i.BarCode

    AND s.ProductNo = i.ProductNo

WHERE s.SoldDate = '20090420' ;

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SQL Server: JOIN vs IN vs EXISTS - the logical difference

Mastering the SQL UPDATE Statement