This example applies sampling rates 20%, 30%, and 40% to categories fair, very good, and excellent, respectively, and rounds the number sampled to the nearest integer.
Input
- score_category, as in Sampling Example: Unconditional, Single Sample Rate
SQL Call
The syntax elements StratumColumn and Strata always appear together.
SELECT * FROM Sampling( ON score_category PARTITION BY ANY USING SampleFraction(0.2, 0.3, 0.4) StratumColumn('stratum') Strata('fair', 'very good', 'excellent') Seed(2) ) AS dt ORDER BY stratum, id, score;
Output
id score stratum --- ----- --------- 5 90.0 excellent 35 94.0 excellent 60 97.0 excellent 70 95.0 excellent 76 100.0 excellent 78 91.0 excellent 90 100.0 excellent 10 27.0 fair 14 52.0 fair 23 14.0 fair 27 44.0 fair 32 3.0 fair 45 21.0 fair 65 53.0 fair 71 59.0 fair 72 79.0 fair 100 18.0 fair 2 83.0 very good 20 85.0 very good 53 87.0 very good 83 81.0 very good
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