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Query performance in current systems depends significantly on tuning: how well the query matches the available indexes, materialized views etc. Even in a well tuned system, there are always some queries that take much longer than others. This frustrates users who increasingly want consistent response times to ad hoc queries. We argue that query processors(More)
llbstract This paper proposes schemes for fast page transfer between transaction system Instances In a shared disks (SD) environment where all the sharing Instances can read and modify the same data Fast page transfer improves transaction response time and concur-rency because one or more disk I/OS are avoided while transferring a page from a system which(More)
This paper presents an algorithm, called ARIES/CSA (<italic>Algorithm for Recovery and Isolation Exploiting Semantics for Client-Server Architectures</italic>), for performing recovery correctly in client-server (CS) architectures. In CS, the server manages the disk version of the database. The clients, after obtaining database pages from the server, cache(More)
We describe an efficient method for supporting incremental and full archiving of data bases (e.g., individual files). Customers archive their data bases quite frequently to minimize the duration of data outage. Because of the growing sizes of data bases and the ever increasing need for high availability of data, the efficiency of the archive copy utility is(More)
This paper describes a technique for use when multiple instances of a data base management system (DBMS), each with its own cache (buffer pool), can directly read and modify any data stored on a set of shared disks. Global locking and coherency control protocols are necessary in this context for assuring transaction consistency and for maintaining coherency(More)
RID-List (row id list) intersection is a common strategy in query processing, used in star joins, column stores, and even search engines. To apply a conjunction of predicates on a table, a query process ordoes index lookups to form sorted RID-lists (or bitmap) of the rows matching each predicate, then intersects the RID-lists via an AND-tree, and finally(More)
1 Motivations A wide variety of applications require access to multiple heterogeneous, distributed data sources. By transparently integrating such diverse data sources, underlying differences in DBMSs, languages, and data models can be hidden and users can use a single data model and a single high-level query language to access the unified data through a(More)
As relational DBMSs become more and more popular and as organizations grow, the sizes of individual tables are increasing dramatically. Unfortunately, current DBMSs do not allow updates to be performed on a table while an index (e.g., a B<supscrpt>+</supscrpt>-tree) is being built for that table, thereby decreasing the systems' availability. This paper(More)