G
George Potemkin
Guest
I would add two metrics - Seek Ratio and Read Ratio. Seek Path = sum of abs(current dbkey - previous dbkey) where dbkey is a block address of the records (rather than recid). It's like a distance covered by a player during a game, Seek Ratio = Seek Path / (max dbkey - min dbkey) Read Ratio: Let's assume database was started with -B 1. How many OS reads a query will create compated to the number of data blocks used by a table. The upper limit is RPB. It seems to be similar to the "%Sequential" introduced by Tom Bascom in his "1, 2, 3… Scatter!" presentation: dbappraise.com/.../123Scatter.pptx %Sequential = the percentage of time that the NEXT record in index order is in the same block. Best regards, George
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