Table Normalization (Parse comma separated fields into individual records)

Question

I have a table like this:

Device

DeviceId   Parts

1          Part1, Part2, Part3
2          Part2, Part3, Part4
3          Part1

I would like to create a table 'Parts', export data from Parts column to the new table. I will drop the Parts column after that

Expected result

Parts

PartId PartName

  1      Part1
  2      Part2
  3      Part3
  4      Part4

DevicePart

DeviceId PartId

  1      1
  1      2
  1      3
  2      2
  2      3
  2      4
  3      1

Can I do this in SQL Server 2008 without using cursors?

Answer 1

-- Setup:

declare @Device table(DeviceId int primary key, Parts varchar(1000))
declare @Part table(PartId int identity(1,1) primary key, PartName varchar(100))
declare @DevicePart table(DeviceId int, PartId int)

insert @Device
values
    (1, 'Part1, Part2, Part3'),
    (2, 'Part2, Part3, Part4'),
    (3, 'Part1')

--Script:

declare @DevicePartTemp table(DeviceId int, PartName varchar(100))

insert @DevicePartTemp
select DeviceId, ltrim(x.value('.', 'varchar(100)'))
from
(
    select DeviceId, cast('<x>' + replace(Parts, ',', '</x><x>') + '</x>' as xml) XmlColumn
    from @Device
)tt
cross apply
    XmlColumn.nodes('x') as Nodes(x)


insert @Part
select distinct PartName
from @DevicePartTemp

insert @DevicePart
select tmp.DeviceId, prt.PartId
from @DevicePartTemp tmp 
    join @Part prt on
        prt.PartName = tmp.PartName

-- Result:

select *
from @Part

PartId      PartName
----------- ---------
1           Part1
2           Part2
3           Part3
4           Part4


select *
from @DevicePart

DeviceId    PartId
----------- -----------
1           1
1           2
1           3
2           2
2           3
2           4
3           1   

Answer 2

You will need a Tally table to accomplish this without a cursor.

Follow the instructions to create a tally table here: Tally Tables by Jeff Moden

This script will put the table into your Temp database, so you probably want to change the "Use DB" statement

Then you can run the script below to insert a breakdown of Devices and Parts into a temp table. You should then be able to join on your part table by the part name (to get the ID) and insert into your new DevicePart table.

select *, 
--substring(d.parts, 1, t.n)
substring(d.parts, t.n, charindex(', ', d.parts + ', ',t.n) - t.n) 'Part'
into #devicesparts
from device d
cross join tally t
where t.n < (select max(len(parts))+ 1 from device)
and substring(', ' + d.parts, t.n, 1) = ', '