SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1992c9e43f829931b3ffd866b3b27dba09a5dcc4181a05deda444e3de76b3b8f' 
  AND token = 'h9yY52cDTNw3zxNgFKN/Bf7pU6EXPmEO2+E0VArvFmk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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