Transactional Database

A transactional database is a set of transactions.

Each transaction contains a transaction-identifier (TID) and a set of items.

Example:

A sample transactional database containing the items from a to f is shown in below.

TID

Transactions

1

a, b, c

2

d, e

3

a, e, f

Rules to create a transactional database:

  • Since the TID of a transaction directly represents its row number in a database, we the algorithms in PAMI ignore the TID information to save storage space and processing time.

  • The items in a transactional database can be integers or strings.

  • All items in a transaction must be seperated with a separator.

  • ‘ Tab space ’ is the default seperator used by the mining algorithms in PAMI. However, transactional databases can also be constructed using other separators, such as comma and space.

Format:

>>>  item1<sep>item2<sep>...<sep>itemN

Example:

>>>    a   b   c
       a   d   e   f
       b   d