materialized views - praktischer einsatz vor und in 12c

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Materialized Views – Praktischer Einsatz vor und in 12c

© SYNTEGRIS INFORMATION SOLUTIONS GMBH

Syntegris information solutions GmbH

• Mittelständisches IT-Unternehmen

• 40 Mitarbeiter (Berater, Entwickler, Architekten)

• Gründung: 2000

• Sitz: Neu-Isenburg, Hessen

• Oracle Gold Partner mit Spezialisierung für Datenbanken

• Bereiche: Data Warehouse, Business Process Development, Anwendungsentwicklung für Oracle Datenbanken, Administration Oracle/Solaris, Consulting, Schulung



What are MVs?

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> View: SQL is executed

> Materialized:

result set is stored in a table

> Legacy: snapshot (Oracle 8i)



Use case 1: Aggregation

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Advantages

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> performance feature

> query rewrite

> easy confguration

(built-in Oracle feature)



Use case 2: Replication

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Advantages

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> mass deployment (templates)

> site – specifc customization

(e.g. timing of refresh)

> connection only during refresh

> easy confguration

(built-in Oracle feature)



Real world example?



Chemical Substances

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> ordering vials/tubes/plates

differ on each site

> meta data about substances

same on each site



GUI



Considerations

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Code?



Options

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COMPLETE REFRESH



FAST REFRESH



BUILD DEFERRED



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> MV is readable all the time

> Index maintenance per row

> REDO and UNDO



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> tuncate is faster (High Water Mark)

> minimal Index maintenance

> direct path load

> no UNDO and less redo

> MV readable?



Fast Refresh - Limits

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> Use ANSI Join Syntax

> Select ROWIDs when joining

> bulk load operations master table



ROWID: reorganization / truncating of the master

will force a complete refresh



Change Management

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PREBUILD TABLE



OUT_OF_PLACE REFRESH

Danke

SYNTEGRIS INFORMATION SOLUTIONS GMBHHERMANNSTRASSE 54-56

63263 NEU-ISENBURG

FON (06102) 29 86 68FAX (06102) 55 88 06

[email protected]

materialized views - praktischer einsatz vor und in 12c

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