SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56a4a3f069dd6a464af23e9d3862cdecbca0ced5b90fe14a615713dba9b0d885' 
  AND token = 'PH/jXJ1q2qo4wZdPB4Lg5DnQj4U0auM2lMvbFURrcnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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