SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac6e9016db83aa63aac2c27e5a5f86001fbb9012f78e1145da4cd0fe527a3f37' 
  AND token = 'Boqawpatizu3/uiQXFtTMrBoVuViHdFzO85l4C8zBys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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