SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff6ee933f75eb8b35ddc36e13930585003cc0eecf3b25fc184511e0a24c8190a' 
  AND token = 'sXc20XrDuiLBlepVUWNy5fSfSxvAAtJUR4gGOhpmVCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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