Asp.Net, 1 datasource or 4 datasources is more efficient?

Hi,

I am populating 4 dropdownlists with distinct values from columns from my DB table. I would like to ask is it more efficient to have for datsources for each dropdownlist or somehow create 1 datasource that contains the unique values from each column?

I have several other datasources so would like to limit how many are used on the page.

Manager	PMList	ClientList	ProductList
Name1	PM2	ClientA	ProductA
Name2	PM1	ClientA	ProductC
Name3	PM2	ClientA	ProductD
Name4	PM1	ClientA	ProductF
Name5	PM1	ClientA	ProductF
Name6	PM1	ClientA	ProductC
Name7	PM1	ClientB	ProductC
Name8	PM2	ClientB	ProductA
Name9	PM2	ClientB	ProductF
Name10	PM1	ClientB	ProductF
Name11	PM1	ClientB	ProductC

Select allOpen in new window

Thanks for any help.