Updating Logical Databases
نویسندگان
چکیده
We suggest a new approach to database updates, in which a database is treated as a collection of theories. We investigate two issues: simultaneous multiple update operations and equivalence of databases under update operations.
منابع مشابه
Belief Revision: A Vade-Mecum
This paper contains a brief survey of the area of belief revision and its relation to updating of logical databases as it has developed during the last years. A set of rationality postulates for revisions are presented. A couple of semi-algorithmic models of revision and updating are introduced. The models are connected to the postulates via some representation theorems. Finally, the relation b...
متن کاملApproximate Update of Logical Databases
In 6, 7], we presented syntactic characterizations and algorithms for computing the result of updating and revising a logical database under various approaches proposed in the literature. In this paper we focus on the design of versions of these algorithms able to provide an approximate answer if interrupted before completion. We use the PMA approach to update 18] as the main example, but the r...
متن کاملOn updates with integrity constraints
In his paper “Making Counterfactual Assumptions” Frank Veltman has proposed a new semantics for counterfactual conditionals. It is based on a particular update operation, and we show that it provides a new and interesting way of updating logical databases under integrity constraints which generalizes in particular Winslett’s PMA.
متن کاملA Formal Petri Net Based Model for Antivirus Update Agent System
In this paper, a formal model for antivirus update agent system is presented based on mobile agent technology and predicate/transition Petri nets. The mobile agent system contains two mobile agents called DCA and UNA. It sends out agents to update antivirus on client computers in a network. Each agent takes on a specified responsibility. First, DCA roams through the network and check the last d...
متن کاملEnforcing User-Defined Constraints during the Run-Time in OODB
In this paper a run-time model is proposed. The run-time model enforces integrity constraints for attributes that are derived from composition and inheritance hierarchies. The run-time model is designed for enforcing the logical integrity constraints in object-oriented databases during the run-time. A new technique called detection method is designed to check the object meta data to detect and ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Advances in Computing Research
دوره 3 شماره
صفحات -
تاریخ انتشار 1986