MySQL - Slightly Optimized Solution
\nSELECT actor_id as ACTOR_ID, director_id as DIRECTOR_ID\nFROM ActorDirector\nGROUP BY actor_id, director_id\nHAVING(COUNT(DISTINCT ActorDirector.timestamp) >=
```\nSELECT actor_id as ACTOR_ID, director_id as DIRECTOR_ID\nFROM ActorDirector\nGROUP BY actor_id, director_id\nHAVING(COUNT(DISTINCT ActorDirector.timestamp) >= 3);\n```\n\nMy original solution included a ```COUNT(*)``` which produced a result faster than only 5% of other submissions.\nAfter switching to counting only the distinct timestamps, the result proved faster than 42% of other submissions - which is still not ideal, but an interesting testiment to incremental query optimization.
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