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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
| system | val1 | val2 |
|---|---|---|
| 1 | {{AB,XX},{EF,ZZ},{IJ,NN},{MN,TT}} | {{CD,YY},{GH,MM},{KL,KK},{OP,QQ}} |
SELECT 1