Here's another way. Comments in the code tell you the right way to do it.
CREATE TABLE #Persons
(Name VARCHAR(20), Birth_Date DATE, Death_Date DATE
-- Use a computed column if you need the text string (n)nnyears
,AgeAtDeath AS (CAST(DATEDIFF(year, Birth_Date, Death_Date) AS VARCHAR(3)) + 'years'))
INSERT INTO #Persons
SELECT 'Grumpy', DATEADD(year, -51, '2012-05-10') - ABS(CHECKSUM(NEWID())) % 100, '2012-05-10'
UNION ALL SELECT 'Sleepy', DATEADD(year, -62, '2012-04-23') - ABS(CHECKSUM(NEWID())) % 100, '2012-04-23'
UNION ALL SELECT 'Dopey', DATEADD(year, -45, '2012-03-15') - ABS(CHECKSUM(NEWID())) % 100, '2012-03-15'
SELECT Name, Birth_Date, Death_Date, AgeAtDeath
-- Parse the text string like this
,AGE=LEFT(AgeAtDeath, PATINDEX('%[^0-9]%', AgeAtDeath)-1)
-- Or just do it the right way
,AGE=DATEDIFF(year, Birth_Date, Death_Date)
FROM #Persons
DROP TABLE #Persons
The set up data you can ignore. It was just for my amusement.
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St