how to get values which are not NULL by sqldatareader?

Hi all, I have command which gets some data from DB, and I want to select just lines which have not in Date column NULL value.
Could some one advice me how to modify folloving command?
 SqlCommand myCmd3 = new SqlCommand("SELECT [Services] from [Ucet] WHERE [IDZak]= @person AND [Amount] >0 ", connection3);
Thanks Mira

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