SELECT *
is a very bad habit ; better just ask for the columns you need, and name them explicitely.
Moreover, with MS SQL Server you have to specify the joins between both tables ; without knowing the exact column names, it's hard to tell, but this could be something like:
SELECT
[frugt].[frugtid]
,[frugt].[whatever]
,[groent].[groentid]
,[groent].[whatever]
FROM [frugt] INNER JOIN [groent] ON [frugt].[frugtid] = [groent].[frugtid]
or
FROM [frugt] INNER JOIN [groent] ON [frugt].[groentid] = [groent].[groentid]
depending on how both tables are related to each other.
[edit] Solution for an
UNION
query:
SELECT
'frugt' AS Type
,[frugt].[frugt_id] AS Id
,[frugt].[frugt_navn] AS Navn
,[frugt].[vaerdi] AS Vaerdi
FROM [frugt]
UNION
SELECT
'groent'
,[groent].[groent_id]
,[groent].[groent_navn]
,[groent].[groent_vaerdi]
FROM [groent]
ORDER BY Type
[/edit]