Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e34ac966c62ad518e21fada9b4f14d66c5ea8a456fa6c81e5eea172a11ca0250' 
  AND token = 'K5B+JTUvNx9StNey76JGjLt0jRv2MUhLUC11FhMlrg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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