OLTP vs. DWH

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Tom Kyte im Oracle Mag 03/04 2012 S. 11/12 (sinngemäß und verkürzt):

Szenario: Abfrage von 1% der Daten einer Tabelle

OLTP: Index bauen und benutzen

DWH: Full Table Scan

Erklärung:
1% Zeilen einer Tabelle mit 100 Mio Zeilen sind 1 Mio Zeilen => 1 Mio single-block Operationen gegen die Tabelle => dauert ca. 1,5h;
Full table scan geht wesentlich schneller..

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