Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75c8eb1a8d936dc34c7bcaad785d5f05e1ebf7181136b52193f800b3c0c918bd' 
  AND token = '+NUJhlq2Vu7Yzh+ENDr+LGMaDt0LTidGXMcYoHqKzoc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}