Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68b92e7e8052843a4071d81adaa2bf2784d351a4b6f7d02f960a5176e3d9eb56' 
  AND token = 'EYI1ZiFxOB8JnkP+JXj9y0MTDVYL64Hk7gvET3XJVEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}