For a general discussion on 'D'-shaped tables, see Wang Shixiang, Connoisseurship of Chinese Furniture: Ming and Early Qing Dynasties, vol. I, Hong Kong, 1990, p. 73.
The present example differs from original 'D'-form tables as the latter traditionally came in pairs and were joined to form a single circular table. Those can be identified not only by their shape but also by their construction. The rear top board would have tenons which were joined to the other table. In addition, the rear legs would be sawn in half such that when the tables were assembled together the width of the leg would equal that of the other legs. However, in this case, the width of the rear legs is equal to that of the others, the rear of the table is both decorated with a similar ruyi design, and lacks the tenons with which it would have been joined to another table, all of which suggest that this table was meant to have been used singly.