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Database System

New Materialized View

.

.5210421012 Com26

52104210 Com26

..

52104210 Com26..5210421035 Com26

..52104210 Com26

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Database System

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Material View View Database

Algorithm Material View - Algorithm View

Material View View Database

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1. Materialized View

2. Materialized View View3. Materialized View4. Materialized View5. Materialized View6. New Material View

7.

New Material View8. - Material View

4445661

213

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1. Materialized View

Materialized View Snapshot Table View query table query query Database table query Table View Table Snapshot

MaterialView Update 2. Materialized View View

Materialized View View Link Definition Base Table Table DBA Refresh Data User MaterialView Select Statement Base Table

View Materialized view

1. Statementbase table(logical representation of table)2. Select

Insert, Update, Delete

1. duplicate data base tableMview accessdata View2. Select

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view Insert,Update, Delete view

3. Materialized View3.1 Materialized ViewCREATE MATERIALIZED VIEW jwt_game_mvas SELECT *FROM big_tablebtWHERE bt.branch = 'BANGKOK'

AND bt.price> 1253.2 Update Materialized ViewALTER MATERIALIZED VIEW

jwt_gamesalesbkk_mv REFRESH COMPLETE3.3 Materialized View Update

CREATE MATERIALIZED VIEWjwt_foobar_mv REFRESH COMPLETE START WITHSYSDATE NEXT SYSDATE + 1 AS select bar from foo4. Materialized View 1. View

2. MV

MV

3. MV Feature Query Rewrite MV MV

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wan Auepanwiriyakul Two-Phase Optimization for SelectingMaterializedViews in a Data Warehouse

6.1 Query database Data

Warehouse Material View

Two Phase Optimized (2PO) Simulated Annealing (SA) algorithm Iterative Improvement(II) algorithm MULTIPLE VIEWPROCESSING PLAN (MVPP) 2PO

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MVPP Plan

Material View Performance

Query Query DataWarehousing Table Join Aggregate summary table summary query Summary Level Key

1. Summary Table Link Base Table Summary Table SELECT statement summary table

2. Summary table Refresh Update DBA Data Warehouse SummaryTable

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Query

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MULTIPLE VIEW PROCESSING PLAN

(MVPP)

6.2

Iterative Improvement (II)

Algorithm SimulatedAnnealing (SA) algorithm

6.2.1 Iterative Improvement (II) Algorithm

1. random starting point2. at the starting point, a random neighbor is selected3. if the neighbors cost is lower than currents cost

then move is carried out and aneighbor is sought4. performs random series of move and accepts only

downhill ones until it reachesa local minimum

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6.2.2 Simulated Annealing(SA) algorithm

1. random starting point

2. at the starting point, a random neighbor is selected3. compare neighbors cost and currents cost3.1 if the neighbors cost is lower than currents

cost then move is carried out and a neighbor is sought3.2 otherwise moving to neighbors state or

staying in currents state with probability4. performs random series of move and accepts both ofdownhill and uphill until it reaches a local minimum

Two Phase Optimized (2PO) for SelectingMaterialized View II SA

1. Input a MVPP represented by a DAG2. Use width-first searching method to search throughall of the nodes in the DAG and produce an orderedsequence of these nodes into a binary string3. Call Iterative Improvement algorithm4. Call Simulated Annealing algorithm5. Present set of views to materialized with minimum

cost Cost Model Materialized View

Selection

Total query processingcost isTotal maintenance costTotal cost of thematerialized views

Q Cost of queryM set of materialized views

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2 Query

8. -Material View

data query base table

view view data base table