selecting multiple instances of a record based on record lifespan over years I have a table of items that have a origin date and a life span. I want to create a procedure that selects all of the items that will need to be replaced in a specific duration. I feel like there is a math way of doing this in the where clause of a single select. The only way i can think of doing it is iterating though the years and appending the items that would be up for replacement... that seems super slow and inefficient. How should I approach this issue?



Details per comment requests:

Database Engine: SQL Server 2005

Source Table:

CREATE TABLE Items
(
    ID int,
    ItemName varchar(255),
    InstallYear int,
    UsefullLife int
);


Desired stored procedure format:

GetReplacementsWithinYearRange(startyear int, endyear int)


Desired output:

ItemID - ItemName - ReplaceYear




More details:

Sample Records:

1  item1  2010  5    
2  item2  2011  6


Desired results for range between 2010 and 2030:

1  item1  2010
1  item1  2015
1  item1  2020
1  item1  2025
1  item1  2030
2  item2  2011
2  item2  2017
2  item2  2023
2  item2  2029
Am I over simplifying here?

CREATE TABLE Items (ItemID int, ItemName nvarchar(255), InstallYear int, Life int)

INSERT INTO Items VALUES (1,'test1',2010,2)
INSERT INTO Items VALUES (2,'test2',2011,2)
INSERT INTO Items VALUES (3,'test3',2012,5)
INSERT INTO Items VALUES (4,'test4',2013,3)

SELECT * FROM Items
GO

CREATE PROCEDURE GetItemLifetimeInfo
(
    @StartYear int,
    @EndYear int
)
AS
BEGIN
    SELECT *, InstallYear + Life AS ReplaceYear 
    FROM Items 
    WHERE InstallYear &lt;= @EndYear AND (InstallYear + Life) &gt;= @StartYear;
END
GO

EXEC GetItemLifetimeInfo 2011, 2022;


Returns:

ItemID  ItemName    InstallYear Life    ReplaceYear
1       test1       2010        2       2012
2       test2       2011        2       2013
3       test3       2012        5       2017
4       test4       2013        3       2016




This works:

CREATE PROCEDURE GetItemLifetimeInfo
(
    @StartYear int,
    @EndYear int
)
AS
BEGIN
    WITH ReplaceYears(ItemID, [Year])
    AS (
        SELECT ItemID, Life
        FROM Items
        UNION ALL
        SELECT Items.ItemID, Items.Life + ReplaceYears.Year
        FROM Items
            INNER JOIN ReplaceYears ON Items.ItemID = ReplaceYears.ItemID
        WHERE ReplaceYears.Year &lt;= (@EndYear - @StartYear)
    )
    SELECT Items.ItemID, InstallYear + ReplaceYears.Year AS ReplaceYear 
    FROM Items
        INNER JOIN ReplaceYears ON Items.ItemID = ReplaceYears.ItemID 
    WHERE InstallYear + ReplaceYears.Year &lt;= @EndYear 
        AND (InstallYear + ReplaceYears.Year) &gt;= @StartYear
    ORDER BY 1,2
END

EXEC GetItemLifetimeInfo 2011,2022;

ItemID  ReplaceYear
1   2012
1   2014
1   2016
1   2018
1   2020
1   2022
2   2013
2   2015
2   2017
2   2019
2   2021
3   2017
3   2022
4   2016
4   2019
4   2022