sql server how to use param with xml query?

[Pico]

I have this code working \[code\]UPDATE UserDataSET Data.modify('delete(/UsersData/UserXml[@user_id=23445])[1]') WHERE Id = 11;\[/code\]But when I try this code it throw ex\[code\]declare @myXmlQuery nvarchar(120)set @myXmlQuery = '/UsersData/UserXml[@user_id=23445]'UPDATE UserDataSET Data.modify('delete(sql:variable("@myXmlQuery"))[1]')WHERE Id = 11;\[/code\]I get this ex : \[quote\] Msg 2264, Level 16, State 1, Line 11 XQuery [UserData.Data.modify()]: Only non-document nodes may be deleted, found 'xs:string'\[/quote\]Any ideas ? thanks.