Thumbnail
Access Restriction
Open

Author Truong, Thanh ♦ Risch, Tore
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Scalable Numerical Query ♦ Algebraic Inequality Transformation ♦ Data Stream ♦ Numerical Condition ♦ Experimental Result ♦ Uti-lize Available Index ♦ Log Da-ta ♦ Historical Analysis ♦ Stream Log Analysis System ♦ Query Transformation Algorithm Aqit ♦ Query Optimizer ♦ Sql Query ♦ Sensor Value ♦ Commercial Dbms ♦ Sus-pected Deviation ♦ Scalable Sql Query ♦ Algebraic Inequality ♦ Ordered Indexed Attribute ♦ Relational Database System ♦ Normal Behavior ♦ Sensor Reading ♦ Transforms Sql Que-ries ♦ Al-gebraic Query Inequality Transformation
Abstract Abstract. To enable historical analyses of logged data streams by SQL queries, the Stream Log Analysis System (SLAS) bulk loads data streams derived from sensor readings into a relational database system. SQL queries over such log da-ta often involve numerical conditions containing inequalities, e.g. to find sus-pected deviations from normal behavior based on some function over measured sensor values. However, such queries are often slow to execute, because the query optimizer is unable to utilize ordered indexed attributes inside numerical conditions. In order to speed up the queries they need to be reformulated to uti-lize available indexes. In SLAS the query transformation algorithm AQIT (Al-gebraic Query Inequality Transformation) automatically transforms SQL que-ries involving a class of algebraic inequalities into more scalable SQL queries utilizing ordered indexes. The experimental results show that the queries exe-cute substantially faster by a commercial DBMS when AQIT has been applied to preprocess them. 1
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study
Learning Resource Type Article