SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d74e3f9ad9d8a63b59eac43ae4574b9bedb97765b5a317b2facd28233816afc' 
  AND token = 'jgzhLlJO8ljllF9nGr/S1Zxbmgg0sEK3qloFGrfRPH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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