If you want to delete the demo data ceu company in ax2012 feature pack then you can delete from sql by this query.
DELETE FROM DataArea WHERE DataArea.ID = 'CEU'
DELETE FROM CompanyDomainList WHERE CompanyDomainList.CompanyID = 'CEU
But this will delete company name not whole data of company.
DELETE FROM DataArea WHERE DataArea.ID = 'CEU'
DELETE FROM CompanyDomainList WHERE CompanyDomainList.CompanyID = 'CEU
But this will delete company name not whole data of company.