“…Data mining is used to find patterns (or itemsets) hidden within data, and associations among the patterns. In particular, frequent pattern mining plays an essential role in many data mining tasks such as mining association rules [1], interesting measures [3,26], correlations [22,34], sequential patterns [8,29,41,42], constraint-based frequent patterns [5,40], graph patterns [35], emerging patterns [11,19,27] and approximate patterns [39]. Mining information and knowledge from very large databases is not easy since it takes a long time to process large datasets and the amount of discovered knowledge, and because the number of patterns can be significant and redundant.…”