Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a57c87bc3f84932131b12a11ee50f74ee2b1f23006a2dc7f9818ce33bfde91c8' 
  AND token = '9xmRU97fNg03Ah1T3XSjENpsCDDlSgQKNtkleGshUB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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