Abstract: Time is an inherent property of data in the real world and also is an important basic characteristic of privacy data. We can delve into the problem about data privacy protection if we take time property as a constraint condition. On the consideration about privacy protection and data security, we combined the data temporal property with security level of the different data granularity and then proposed the conception of time effectiveness about data security. Further- more, we applied the different level to generalize the different items or transactions in order to protect data privacy, and presented the algorithm of association rule privacy protection based on temporal constraint. Finally, we analyzed and evaluated the method performance,which include information loss and algorithm effectiveness.

Key words: Privacy preserving,Temporal constraints, Generalization, Data confidential level