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CREATE TABLE
INSERT 0 18
| day | item | flag |
|---|---|---|
| 1 | a | 0 |
| 2 | a | 0 |
| 3 | a | 1 |
| 4 | a | 1 |
| 5 | a | 1 |
| 6 | a | 0 |
| 1 | b | 0 |
| 2 | b | 0 |
| 3 | b | 0 |
| 4 | b | 1 |
| 5 | b | 0 |
| 6 | b | 0 |
| 7 | b | 1 |
| 8 | b | 1 |
| 9 | b | 1 |
| 1 | c | 0 |
| 2 | c | 1 |
| 3 | c | 1 |
SELECT 18
| day | item | flag | is_diff | sum |
|---|---|---|---|---|
| 1 | a | 0 | 1 | 1 |
| 2 | a | 0 | 0 | 1 |
| 3 | a | 1 | 1 | 2 |
| 4 | a | 1 | 0 | 2 |
| 5 | a | 1 | 0 | 2 |
| 6 | a | 0 | 1 | 3 |
| 1 | b | 0 | 1 | 1 |
| 2 | b | 0 | 0 | 1 |
| 3 | b | 0 | 0 | 1 |
| 4 | b | 1 | 1 | 2 |
| 5 | b | 0 | 1 | 3 |
| 6 | b | 0 | 0 | 3 |
| 7 | b | 1 | 1 | 4 |
| 8 | b | 1 | 0 | 4 |
| 9 | b | 1 | 0 | 4 |
| 1 | c | 0 | 1 | 1 |
| 2 | c | 1 | 1 | 2 |
| 3 | c | 1 | 0 | 2 |
SELECT 18