SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '231a2c152e62d8a9791208c9951b936d6e5fb52131af3771fb1dd077cebc54b9' 
  AND token = '2puLVWYav1Vs1TzbBFv9G5gm2OEuXIivP8jFZyqi+gE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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