Code reviewHardcr-g650

Subject Database cache consistencyLevel Senior–Staff~26 minCommon in Databases & SQL interviewsIndustries Software development, Technology

Question

Review this Python function that increments a counter cached in Redis backed by Postgres.

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Code to reviewpython

1def increment_views(redis, db, post_id):2    cached = redis.get(f"views:{post_id}")3    if cached is None:4        row = db.execute(5            "SELECT views FROM posts WHERE id = %s", (post_id,)6        ).fetchone()7        cached = row[0]8    new_val = int(cached) + 19    redis.set(f"views:{post_id}", new_val)10    db.execute("UPDATE posts SET views = %s WHERE id = %s", (new_val, post_id))

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