TY - JOUR
T1 - Incremental computation of materialized outer-join views
AU - Zou, Xian-Xia
AU - Jia, Wei-Jia
AU - Pan, Jiu-Hui
PY - 2011/4
Y1 - 2011/4
N2 - The algorithm for maintaining materialized outer-join views is proposed to compute the secondary delta by the independent computation of terms. In this algorithm, select project outer-join (SPOJ) views are rewritten as the join-disjunctive normal form first. Then the independent computation of terms is derived from every normal term. Finally common sub-expressions extracted from all of the computation terms are utilized to compute the secondary delta of materialized outer-join views. Experimental results show that the algorithm can reduce the computational cost effectively compared with other counterparts under the same conditions, and furthermore it poses no restrictions on SPOJ views.
AB - The algorithm for maintaining materialized outer-join views is proposed to compute the secondary delta by the independent computation of terms. In this algorithm, select project outer-join (SPOJ) views are rewritten as the join-disjunctive normal form first. Then the independent computation of terms is derived from every normal term. Finally common sub-expressions extracted from all of the computation terms are utilized to compute the secondary delta of materialized outer-join views. Experimental results show that the algorithm can reduce the computational cost effectively compared with other counterparts under the same conditions, and furthermore it poses no restrictions on SPOJ views.
KW - Independent computation of terms
KW - Join-disjunctive normal form
KW - Materialized outer-join view
KW - Subsumption graph
UR - http://www.scopus.com/inward/record.url?scp=79956315334&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-79956315334&origin=recordpage
M3 - RGC 22 - Publication in policy or professional journal
SN - 1001-506X
VL - 33
SP - 938
EP - 942
JO - Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics
JF - Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics
IS - 4
ER -