SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb9fe75bda3ae8e6159f5e6493fb535b89b18ed88cc6baf075ca92d5da344193' 
  AND token = 'stizEGbLqnSKM+B/DLr/5kgHAISbBfTds5r/nr2kuKk=' 
  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"
    }
  }
}