Sequential Database
A sequence represents a collection of itemsets (or transactions) in a particular order. A sequence database is a collection of sequences and their sequence identifiers. An example of a geo-referenced transactional database is as follows:
Rules to create a sequence database:
Items in an itemset have to be seperated by a tab space.
Itemsets in a sequence are seperated using ‘-1’ as a seperator.
Each sequence is represented as a line
The sequence identifier, sid, is not needed to create a sequence database.
Format of a sequence:
>>> item1<sep>item2<sep>...<sep>itemA : item1<sep>item2<sep>...<sep>itemB : item1<sep>item2<sep>...<sep>itemC
Example:
>>> a b c d : a d e : a e f
a b c : b d e : c d e
a e f : c
a e f : a c d : c e