order by in c (libpq)?

Hi All,  I am writing an app in c,  everything works fine except for the

order by in my query.

I am sending the query thusly:

sprintf(querystr, "select * from %s order by %s", table, field);

However the query always comeback in the order in which the data was
originally entered into the data base.

The variable field does actually contain a valid field name,  I have
checked
it.

Any ideas????

Ken
kvp@ocol.com