{
  "columns": [
    "invoiceDate$id",
    "invoiceDate$year",
    "invoiceDate$month",
    "invoiceAmount",
    "invoiceAmount__ytd"
  ],
  "groupBy": [
    "invoiceDate$id",
    "invoiceDate$year",
    "invoiceDate$month"
  ],
  "orderBy": [
    "invoiceDate$id"
  ],
  "timeWindow": {
    "field": "invoiceDate$id",
    "grain": "day",
    "comparison": "ytd",
    "targetMetrics": [
      "invoiceAmount"
    ]
  },
  "limit": 500,
  "slice": [
    {
      "field": "invoiceDate$id",
      "op": "[)",
      "value": [
        "2012-01-01",
        "2013-01-01"
      ]
    }
  ]
}