feat(power-bi): Support incremental refresh on storage Costs table

docs-mslearn/toolkit/changelog.md

@@ -3,7 +3,7 @@ title: FinOps toolkit changelog
 description: Review the latest features and enhancements in the FinOps toolkit, including updates to FinOps hubs, Power BI reports, and more.
 author: MSBrett
 ms.author: brettwil
-ms.date: 10/28/2026
+ms.date: 10/29/2026
 ms.topic: reference
 ms.service: finops
 ms.subservice: finops-toolkit
@@ -25,6 +25,15 @@ This article summarizes the features and enhancements in each release of the Fin
 
 The following section lists features and enhancements that are currently in development.
 
+### [Power BI reports](power-bi/reports.md)
+
+_**Breaking change**_
+
+- **Added**
+  - Added support for incremental refresh on the **Costs** table in storage reports. Power BI can now detect the **RangeStart**/**RangeEnd** filter on the `x_IncrementalRefreshDate` column. To learn more, see [Configure incremental refresh](power-bi/setup.md#configure-incremental-refresh) ([#2314](https://github.com/microsoft/finops-toolkit/issues/2314)).
+- **Changed**
+  - Changed the `x_IncrementalRefreshDate` column in storage reports from text to Date/Time. Update any custom filters, measures, or visuals that treat it as text or a number ([#2314](https://github.com/microsoft/finops-toolkit/issues/2314)).
+
 -->
 
 <br><a name="latest"></a>

docs-mslearn/toolkit/help/data-dictionary.md

@@ -3,7 +3,7 @@ title: FinOps toolkit data dictionary
 description: This article describes the column names found in FinOps toolkit solutions, including columns from Cost Management and FOCUS.
 author: flanakin
 ms.author: micflan
-ms.date: 06/21/2026
+ms.date: 10/29/2026
 ms.topic: concept-article
 ms.service: finops
 ms.subservice: finops-toolkit
@@ -113,7 +113,7 @@ Quick links:
 | EffectiveCostRunningTotal                        | Derived. Used in Power BI to calculate the total `EffectiveCost` for the reporting period up to and including the specified day. For instance, the cost for the 15th will include the cost from the 1st through the 15th.                                                                                               |
 | EffectivePricingCost                             | `EffectiveCost` in the pricing currency.                                                                                                                                                                                                                                                                                |
 | EffectiveUnitPrice                               | Amortized price per unit after commitment discounts.                                                                                                                                                                                                                                                                    |
-| <a name="i"></a>IncrementalRefreshDate           | Derived. Numeric version of the `ChargePeriodStart` column to simplify setup for incremental refresh.                                                                                                                                                                                                                   |
+| <a name="i"></a>IncrementalRefreshDate           | Derived. Date/Time version of the charge date (for example, `ChargePeriodStart`) at midnight to simplify setup for incremental refresh.                                                                                                                                                                                 |
 | InvoiceId                                        | Unique identifier for the invoice the charge is included in. Only available for closed months after the invoice is published. Renamed from **x_InvoiceId** in FOCUS 1.2.                                                                                                                                                |
 | InvoiceIssuerId                                  | Unique identifier of the organization that generated the invoice.                                                                                                                                                                                                                                                       |
 | InvoiceIssuerName                                | Name of the organization that generated the invoice. Only supported for CSP accounts. Not supported for EA or MCA accounts that a partner manages due to data not being provided by Cost Management.                                                                                                                    |

docs-mslearn/toolkit/power-bi/setup.md

@@ -3,7 +3,7 @@ title: Set up Power BI reports
 description: Learn how to set up Power BI FinOps reports using the FinOps toolkit, customize visuals, and connect to your cost data for detailed analysis.
 author: flanakin
 ms.author: micflan
-ms.date: 07/30/2026
+ms.date: 10/29/2026
 ms.topic: how-to
 ms.service: finops
 ms.subservice: finops-toolkit
@@ -105,8 +105,8 @@ The FinOps toolkit Power BI reports include preconfigured visuals, but aren't co
        4. Append the container and export path, if applicable.
    - **Number of Months** – Optional number of closed months you would like to report on if you want to always show a specific number of recent months. If not specified, the report will include all data in storage.
    - **RangeStart** / **RangeEnd** – Optional date range you would like to limit to. If not specified, the report will include all data in storage.
-     - We generally recommend leaving these dates empty. They are included to support incremental refresh.
-     - If you need to configure incremental refresh, consider using [FinOps hubs](../hubs/finops-hubs-overview.md) with Data Explorer instead.
+     - We generally recommend leaving these dates empty. They are included to support incremental refresh. For steps, see [Configure incremental refresh](#configure-incremental-refresh).
+     - For larger datasets, consider using [FinOps hubs](../hubs/finops-hubs-overview.md) with Data Explorer instead.
      - FinOps hubs with Data Explorer offers improved performance and is recommended for anyone monitoring over $100,000 in total spend.
      - Storage reports only support ~$2 million of data without incremental refresh and ~$2 million per month in raw cost details. To learn more, see [Configure incremental refresh](/power-bi/connect-data/incremental-refresh-configure#define-policy).
 
@@ -121,6 +121,28 @@ If you run into any issues syncing your data, see [Troubleshooting Power BI repo
 
 <br>
 
+## Configure incremental refresh
+
+Storage reports support incremental refresh on the **Costs** table. Incremental refresh is only needed when you have more cost data than Power BI can load in one refresh. If you're monitoring over $100,000 in total spend, consider [FinOps hubs](../hubs/finops-hubs-overview.md) with Data Explorer instead.
+
+To configure incremental refresh:
+
+1. Open the storage report in Power BI Desktop.
+2. Select **Transform data** to open Power Query Editor.
+3. Set **RangeStart** and **RangeEnd** to a small, recent date range, like the first day of last month and the first day of this month.
+   - These values only apply in Power BI Desktop. The incremental refresh policy replaces them after you publish.
+4. Select **Close & Apply**.
+5. In the **Data** pane, right-click the **Costs** table and select **Incremental refresh**.
+6. Turn on **Incrementally refresh this table**, set the archive and refresh periods, and then select **Apply**.
+   - The **Costs** query filters the `x_IncrementalRefreshDate` column by **RangeStart** and **RangeEnd**.
+7. Publish the report and refresh the semantic model in the Power BI service.
+
+Rows without a charge date (`x_IncrementalRefreshDate` is empty) are kept in every partition when a range is set, so they can be counted more than once. These rows are rare, but if you see inflated totals after enabling incremental refresh, check for them.
+
+If you leave **RangeStart** and **RangeEnd** empty, the **Costs** query doesn't filter by them and the report uses **Number of Months** as before. To learn more, see [Configure incremental refresh](/power-bi/connect-data/incremental-refresh-configure).
+
+<br>
+
 ## Use a SAS token to connect data to a report
 
 Shared Access Signature (SAS) tokens allow you to connect to a storage account without end user credentials or setting up a service principal. To connect Power BI reports to your data via SAS tokens:

src/power-bi/storage/Shared.Dataset/definition/expressions.tmdl

@@ -298,7 +298,7 @@ expression ftk_Storage = ```
 				let
 					segments = if d = null then null else Text.SplitAny(Text.From(d), "/- T"),
 					output =
-						try Number.From(Date.From(
+						try DateTime.From(Date.From(
 							if Text.Length(segments{0}) = 4 then segments{0} & "-" & Text.PadStart(segments{1}, 2, "0") & "-" & Text.PadStart(segments{2}, 2, "0")
 							else if Text.Length(segments{2}) = 4 then segments{2} & "-" & Text.PadStart(segments{0}, 2, "0") & "-" & Text.PadStart(segments{1}, 2, "0")
 							else d,
@@ -314,11 +314,11 @@ expression ftk_Storage = ```
 						else if data = "reservationdetails"      then [UsageDate]
 						else if data = "reservationtransactions" then [EventDate]
 						else null // Will not support incremental refresh
-					)
+					), type datetime
 				),
 			FilterRowsByDate = if (start = null and end = null) then RefreshDate else Table.SelectRows(RefreshDate, each
-				(start = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] >= Number.From(DateTime.From(start)))
-				and (end = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] < Number.From(DateTime.From(end)))
+				(start = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] >= Date.StartOfDay(DateTime.From(start)))
+				and (end = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] < Date.StartOfDay(DateTime.From(end)))
 			),
 
 			// TODO: Try using "_" instead of "FilterRowsByDate"

src/power-bi/storage/Shared.Dataset/definition/tables/Costs.tmdl

@@ -1052,7 +1052,8 @@ table Costs
 		annotation PBI_FormatHint = {"isGeneralNumber":true}
 
 	column x_IncrementalRefreshDate
-		dataType: string
+		dataType: dateTime
+		formatString: General Date
 		lineageTag: 73487d4f-b0dd-4d41-8d9e-739636dabab8
 		summarizeBy: none
 		sourceColumn: x_IncrementalRefreshDate
@@ -1733,7 +1734,14 @@ table Costs
 					*/
 
 					// Sort columns alphabetically
-					Output = Table.ReorderColumns(AHB, List.Sort(Table.ColumnNames(AHB)))
+					Sorted = Table.ReorderColumns(AHB, List.Sort(Table.ColumnNames(AHB))),
+
+					// Incremental refresh -- Must be the last step so Power BI detects the RangeStart/RangeEnd filter
+					// Matches the ftk_Storage row filter: whole days, >= start and < end, keeps rows without a date, and keeps all rows when RangeStart/RangeEnd are empty
+					Output = Table.SelectRows(Sorted, each
+						(RangeStart = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] >= Date.StartOfDay(DateTime.From(RangeStart)))
+						and (RangeEnd = null or [x_IncrementalRefreshDate] = null or [x_IncrementalRefreshDate] < Date.StartOfDay(DateTime.From(RangeEnd)))
+					)
 				in
 					Output
 				```

src/power-bi/storage/Shared.Dataset/definition/tables/Prices.tmdl

@@ -108,7 +108,8 @@ table Prices
 		annotation SummarizationSetBy = Automatic
 
 	column x_IncrementalRefreshDate
-		dataType: string
+		dataType: dateTime
+		formatString: General Date
 		lineageTag: 55e08448-a8ac-4f16-98f3-915f443d4117
 		summarizeBy: none
 		sourceColumn: x_IncrementalRefreshDate

src/power-bi/storage/Shared.Dataset/definition/tables/ReservationDetails.tmdl

@@ -85,7 +85,8 @@ table ReservationDetails
 		annotation PBI_FormatHint = {"isGeneralNumber":true}
 
 	column x_IncrementalRefreshDate
-		dataType: string
+		dataType: dateTime
+		formatString: General Date
 		lineageTag: 7631c2d6-b330-42de-8588-967752ced645
 		summarizeBy: none
 		sourceColumn: x_IncrementalRefreshDate

src/power-bi/storage/Shared.Dataset/definition/tables/ReservationRecommendations.tmdl

@@ -3,7 +3,8 @@ table ReservationRecommendations
 	lineageTag: a9b8f96b-84d0-4176-95a1-65eade30a2ef
 
 	column x_IncrementalRefreshDate
-		dataType: string
+		dataType: dateTime
+		formatString: General Date
 		lineageTag: 0d03437c-a892-4d20-9e24-e1ae25b31e47
 		summarizeBy: none
 		sourceColumn: x_IncrementalRefreshDate

src/power-bi/storage/Shared.Dataset/definition/tables/ReservationTransactions.tmdl

@@ -156,7 +156,8 @@ table ReservationTransactions
 		annotation SummarizationSetBy = Automatic
 
 	column x_IncrementalRefreshDate
-		dataType: string
+		dataType: dateTime
+		formatString: General Date
 		lineageTag: db9b73cb-8a9d-455c-88dd-41a7fd42bb2e
 		summarizeBy: none
 		sourceColumn: x_IncrementalRefreshDate

src/powershell/Tests/Lint/PowerBIReports.Tests.ps1

@@ -97,4 +97,27 @@ Describe 'Demo data source' {
         $inList = $text -match ('"' + [regex]::Escape($account) + '"')
         $inList | Should -BeTrue -Because "$account should be in the ftk_DemoFilter storage account list"
     }
+}
+
+Describe 'Storage incremental refresh' {
+    BeforeAll {
+        $tablesDir = Join-Path $PSScriptRoot '../../../power-bi/storage/Shared.Dataset/definition/tables'
+    }
+
+    It 'Ends the Costs query with a RangeStart/RangeEnd row filter' {
+        # Power BI only offers incremental refresh when the table's own query filters rows with RangeStart and RangeEnd
+        $text = Get-Content (Join-Path $tablesDir 'Costs.tmdl') -Raw
+        $isLastStep = $text -match '(?s)Output\s*=\s*Table\.SelectRows\((?<filter>(?:(?!Table\.SelectRows).)*?)\)\s*in\s+Output\s*\r?\n\s*```'
+        $isLastStep | Should -BeTrue -Because 'the final step of the Costs query must be Table.SelectRows so Power BI detects the filter'
+        $filter = $Matches['filter']
+        $filter | Should -Match '\bRangeStart\b'
+        $filter | Should -Match '\bRangeEnd\b'
+        $filter | Should -Match 'x_IncrementalRefreshDate'
+    }
+
+    It 'Types x_IncrementalRefreshDate as dateTime in <_>' -ForEach @('Costs', 'Prices', 'ReservationDetails', 'ReservationRecommendations', 'ReservationTransactions') {
+        $text = Get-Content (Join-Path $tablesDir "$_.tmdl") -Raw
+        $isDateTime = $text -match '(?m)^\tcolumn x_IncrementalRefreshDate\r?\n\t\tdataType: dateTime\b'
+        $isDateTime | Should -BeTrue -Because 'incremental refresh needs a Date/Time column to compare with RangeStart and RangeEnd'
+    }
 }