Question

Let’s supposed I Have a table with products like this

product  |  number
----------------------
aaaa     |     2
bbbb     |     3
cccc     |     1
dddd     |     4

It’s a little more complex, but the idea is the same.

I need to return something like this

aaaa0001
aaaa0002
bbbb0003
bbbb0004
bbbb0005
cccc0006
dddd0007
dddd0008
dddd0009
dddd0010

I mean, each product the number of times specified in the column, with some kind of identificator at the end.

How can I do this ?

I thought of table variable, with identity on the Id

DECLARE @Codigos TABLE (ID INT IDENTITY(1,1), Barra Varchar(50) NOT NULL)

and after the inserts, do

select rtrim(ltrim(barra)) + right('0000' + rtrim(ltrim(cast(id as varchar(10)))),4) from @Codigos

but This mean that I’ll have to insert for each products the number of times in the product variable, like

@Codigos
id     |   Barra
----------------
1      |   aaaa
2      |   aaaa

and I’m facing problems with that. How can I do that ? With a cursor ? That’s what I thought, but I want to know if there’s a better option.

Maximum will be 300 rows in original table.

Answer 1

This should do it:

;WITH CTE AS
(
    SELECT product, Number, 1 RN
    FROM YourTable
    UNION ALL
    SELECT product, Number, RN + 1
    FROM CTE
    WHERE RN + 1 <= Number
)
SELECT product + RIGHT('000' + CAST(RN AS VARCHAR(3)),3) YourColumn
FROM CTE
ORDER BY product, Number
OPTION(MAXRECURSION 0)

Here is a sqlfiddle for you to try.