SQL statement to concatenate categories from hiera

I already checked this question, but that is different as my items can fall under multiple parent nodes and not a single one and I have an extra mapping table instead of everything in one table.

I have a hierarchical structure for mapping products to categories, categories go 3 levels deep (depth is defined in articlegroups.catlevel, 0 being the main category and traversing down to lower category level 2). Also, a product may be in more than 1 category(!).

product details are stored in [products]
articlegroups are defined in [articlegroups]
and the mapping of the products to the articlegroups are defined in [products_category_mapping]

Now, I want to retrieve index the full category path for each item, so with the data provided below, I'd expect these 2 rows as a result:

id          categorystring
2481446     Taarttoppers > Taarttoppers grap'pig  
2481446     Bruidstaart > Taarttoppers > Grappig

Now I can get the separate fields via a statement like this:

SELECT ga.slug_nl as slug_nl_0
FROM articlegroups ga
INNER JOIN products_category_mapping pcm ON pcm.articlegroup_id=ga.id
INNER JOIN products gp on gp.id=pcm.artikelid
WHERE gp.id=2481446

But that just gives me this result:

taarttoppers
grappig
bruidstaart
taarttoppers
grappig

However, I don't know how to concatenate the different category levels respecting the depth of that category level and have a '>' character in between.

script for tables+data

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[articlegroups](
    [id] [int] IDENTITY(1,1) NOT NULL,
    [parentid] [int] NOT NULL,
    [catlevel] [tinyint] NOT NULL CONSTRAINT [DF_articlegroups_lvl0_catlevel]  DEFAULT ((0)),
    [slug_nl] [nvarchar](50) NOT NULL,
 CONSTRAINT [PK_articlegroups] PRIMARY KEY CLUSTERED 
(
    [id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO
/****** Object:  Table [dbo].[products]    Script Date: 28-07-15 15:45:03 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[products](
    [id] [int] IDENTITY(1,1) NOT NULL,
    [artikelnummer] [nvarchar](60) NOT NULL
) ON [PRIMARY]

GO
/****** Object:  Table [dbo].[products_category_mapping]    Script Date: 28-07-15 15:45:03 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[products_category_mapping](
    [artikelid] [int] NOT NULL,
    [articlegroup_id] [int] NOT NULL,
    [createdate] [datetime] NOT NULL CONSTRAINT [DF_products_category_mapping_createdate]  DEFAULT (getdate())
) ON [PRIMARY]

GO
SET IDENTITY_INSERT [dbo].[articlegroups] ON 

GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (1, 0, 0, N'taarttoppers')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (2, 1, 1, N'grappig')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (3, 0, 0, N'feestartikelen')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (4, 3, 1, N'ballonnen')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (5, 3, 1, N'slingers')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (6, 0, 0, N'bruidstaart')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (7, 6, 1, N'taarttoppers')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (8, 7, 2, N'grappig')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (9, 0, 0, N'accessoires')
GO
INSERT [dbo].[articlegroups] ([id], [parentid], [catlevel], [slug_nl]) VALUES (10, 9, 1, N'tiaras')
GO
SET IDENTITY_INSERT [dbo].[articlegroups] OFF
GO
SET IDENTITY_INSERT [dbo].[products] ON 

GO
INSERT [dbo].[products] ([id], [artikelnummer]) VALUES (2481446, N'1013')
GO
SET IDENTITY_INSERT [dbo].[products] OFF
GO
INSERT [dbo].[products_category_mapping] ([artikelid], [articlegroup_id], [createdate]) VALUES (2481446, 1, CAST(N'2015-07-24 20:27:02.890' AS DateTime))
GO
INSERT [dbo].[products_category_mapping] ([artikelid], [articlegroup_id], [createdate]) VALUES (2481446, 2, CAST(N'2015-07-24 20:27:02.890' AS DateTime))
GO
INSERT [dbo].[products_category_mapping] ([artikelid], [articlegroup_id], [createdate]) VALUES (2481446, 6, CAST(N'2015-07-24 20:27:02.890' AS DateTime))
GO
INSERT [dbo].[products_category_mapping] ([artikelid], [articlegroup_id], [createdate]) VALUES (2481446, 7, CAST(N'2015-07-24 20:27:02.890' AS DateTime))
GO
INSERT [dbo].[products_category_mapping] ([artikelid], [articlegroup_id], [createdate]) VALUES (2481446, 8, CAST(N'2015-07-24 20:27:02.890' AS DateTime))
GO
/****** Object:  Index [PK_products]    Script Date: 28-07-15 15:45:03 ******/
ALTER TABLE [dbo].[products] ADD  CONSTRAINT [PK_products] PRIMARY KEY NONCLUSTERED 
(
    [id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
ALTER TABLE [dbo].[products_category_mapping]  WITH CHECK ADD  CONSTRAINT [FK_articlegroups_lvl1_mapping_products] FOREIGN KEY([artikelid])
REFERENCES [dbo].[products] ([id])
ON DELETE CASCADE
GO
ALTER TABLE [dbo].[products_category_mapping] CHECK CONSTRAINT [FK_articlegroups_lvl1_mapping_products]
GO

The data model you have where you store the whole hierarchy for the model helps so that you don't have to use recursion when fetching the groups, but being able to use it for the path, you would need to have also the top level article group to be stored for each row so that it can be used for grouping the data. I made a change to the articlegroups table so that it it contains the toplevelid:

id  parentid    catlevel   toplevelid   slug_nl
1   0           0          1            taarttoppers
2   1           1          1            grappig
3   0           0          3            feestartikelen
4   3           1          3            ballonnen
5   3           1          3            slingers
6   0           0          6            bruidstaart
7   6           1          6            taarttoppers
8   7           2          6            grappig
9   0           0          9            accessoires
10  9           1          9            tiaras

This way you can simply fetch the names like this:

SELECT tmp.toplevelid, categorystring = STUFF((SELECT N' > ' + slug_nl 
  FROM articlegroups AS ga2
   WHERE ga2.toplevelid = tmp.toplevelid 
   ORDER BY catlevel
   FOR XML PATH(N''), TYPE).value(N'.[1]', N'nvarchar(max)'), 1, 3, '')
FROM 
  products gp
  INNER JOIN products_category_mapping pcm ON gp.id=pcm.artikelid
  outer apply (
    select distinct ga.toplevelid
    from articlegroups ga
    where  pcm.articlegroup_id=ga.id
  ) tmp 
WHERE gp.id=2481446
GROUP BY tmp.toplevelid
ORDER BY tmp.toplevelid;

The example in SQL Fiddle.

The downside of this design of course is that if you have changes in the hierarchy, you'll have to update them to every product. The other option is to store the items just to the lowest level and use a recursive CTE to fetch the hierarchy. That's a simpler model to maintain, but it's not as fast to read because the recursion needs to be handled every time.