Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3453a1aacd0d292c109e7f6c44e3b6c7dfe6edb84fd48a91635e243a3e834795' 
  AND token = 'MufH7PL1Czs7v2TF3ElAPUwpZ23XjeenFCzcOXM/cWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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