SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c803efb367e960ce69cdab5a213912987b747f0b9da6c53146d4b9ae7221727' 
  AND token = 'vI/3Y3IUaEdWtx5PEH4ETfZQrefkgzHW7P0QBHTDQnQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}