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CREATE TABLE
INSERT 0 1
INSERT 0 1
INSERT 0 1
| pc | a | b | r |
|---|---|---|---|
| pc1 | a1 | b1 | null |
| pc1 | a2 | b2 | 1 |
| pc1 | a3 | b3 | 2 |
SELECT 3
CREATE TABLE
INSERT 0 1
INSERT 0 1
INSERT 0 1
| pc | a | b | r |
|---|---|---|---|
| pc1 | a1 | b1 | null |
| pc1 | a2 | b2 | 1 |
| pc1 | a3 | b3 | 2 |
SELECT 3