We introduce MD-sketches, which are a particular kind of Finite Sum sketches. Two interesting results about MD-sketches are proved. First, we show that, given two MD-sketches, it is algorithmically decidable whether their model categories are equivalent. Next we show that data-specifications, as used in database-design and software engineering, can be translated to MD-sketches. As a corollary, we obtain that equivalence of data-specifications is decidable.
Keywords: dataspecifications, sketches.
AMS Classification (1991): 18A25, 18C99, 68P15.
Theory and Applications of Categories, Vol. 1, 1995, No. 8, pp 156-173.
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