Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f1a31cc775034cfd69d21709f29927bfefa08cb4eb9d3203224ed20b50cd92b' 
  AND token = '7YAlQkENrnW+zdiMtKUXvzRAJilnUHUyvwD6+15WcGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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