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DROP TABLE
CREATE TABLE
INSERT 0 3
| key1 | key2 | count |
|---|---|---|
| surface | source | 1 |
| surface | segregated | 1 |
| surface | ramp | 1 |
| surface | lit | 1 |
| surface | incline | 2 |
| surface | highway | 3 |
| surface | bicycle | 1 |
| source | lit | 1 |
| source | incline | 1 |
| source | highway | 1 |
| segregated | highway | 1 |
| segregated | bicycle | 1 |
| ramp | incline | 1 |
| ramp | highway | 1 |
| lit | incline | 1 |
| lit | highway | 1 |
| incline | highway | 2 |
| highway | bicycle | 1 |
SELECT 18