A relational model of data for large shared data banks
Communications of the ACM
Distributed query processing in a relational data base system
SIGMOD '78 Proceedings of the 1978 ACM SIGMOD international conference on management of data
A methodology for interpreting tree queries into optimal semi-join expressions
SIGMOD '80 Proceedings of the 1980 ACM SIGMOD international conference on Management of data
Absolute Bounds on Set Intersection and Union Sizes from Distribution Information
IEEE Transactions on Software Engineering
Optimizing Joins in Fragmented Database Systems on a Broadcast Local Network
IEEE Transactions on Software Engineering
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
On the effect of join operations on relation sizes
ACM Transactions on Database Systems (TODS)
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
The Size of Projections of Relations Satisfying a Functional Dependency
VLDB '82 Proceedings of the 8th International Conference on Very Large Data Bases
Note on the expected size of a join
ACM SIGMOD Record
Data base system performance prediction using an analytical model (invited paper)
VLDB '81 Proceedings of the seventh international conference on Very Large Data Bases - Volume 7
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We present a probabilistic model for evaluating the size of relations derived from given relations through relational algebra operators. We define tools to estimate the derived relations size and we state the assumptions underwhich we perform such an evaluation.The particular class of data base schemata in which we evaluate the derived relation size is characterized by properties such as independence between two relations having union-compatible domains or independence between distinct tuples in a relation. We show that, knowing the expected size of all projections of each relation in the database, we can compute the size of each query expressed in relational algebra and we give the results for each operator of this language (selection, projection, union, intersection, e-join).