Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '198f4e3baabe0c8f850f60ce1589be757ca6a598224dc9c614d0b34bd0a532f9' 
  AND token = 'Kv8du3tOcefluOyAQbmh3GoLvQ2af7dYjqvzhIiTXAg=' 
  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"
    }
  }
}