Answer Posted / sat!sh
The data distribution of table among AMPs is called Skew Factor
Generally For Non-Unique PI we get duplicate values so the
more duplicate vales we get more the data have same rowhash
so all the same data will come to same amp, it makes data
distribution inequality,
One amp will store more data and other amp stores less
amount of data, when we are accessing full table, The amp
which is having more data will take longer time and makes
other amps waiting which leads processing wastage
In this situation (unequal distribution of data)we get Skew
Factor High
For this type of tables we should avoid full table scans
ex:
AMP0 AMP1
10000(10%) 9000000(90%)
in this situation skew factor is very high 90%
| Is This Answer Correct ? | 79 Yes | 3 No |
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