Lowell (1/24/2013)
i thought it was clear: i read it as howard saying there is no need to mark an calculated column as persisted in order to index it...it's not a requirement.simple example:
--drop table products
CREATE TABLE Products(
id INT IDENTITY(1, 1) NOT NULL PRIMARY KEY,
pname VARCHAR(30),
CostPerItem MONEY,
ItemsPerCase INT,
ValuePerCase AS CostPerItem * ItemsPerCase
)
INSERT INTO Products
SELECT 'Bananas',.49,40 UNION ALL
SELECT 'Apples',.49,36 UNION ALL
SELECT 'Pineapples',3.49,5
SELECT * FROM Products where ValuePerCase > 18
CREATE INDEX IX_Product_ValuePerCase ON Products(ValuePerCase)
SELECT * FROM Products where ValuePerCase > 18
Seems an odd way to read it in context here, since the OP stated in his original post that he could index a computed column w/o explicitly persisting it. I guess I just didn't understand why that needed to be restated separately.
SQL DBA,SQL Server MVP(07, 08, 09) A socialist is someone who will give you the shirt off *someone else's* back.