From 157be03fb58c82423206f57dbddbabd14fea5abd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Heiko=20Thei=C3=9Fen?= <heiko.theissen@sap.com>
Date: Tue, 18 Feb 2025 14:32:34 +0100
Subject: [PATCH] Aggregation.default mandatory for custom aggregate

---
 advanced/odata.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/advanced/odata.md b/advanced/odata.md
index 13f1ad0ec..f8a2e8f74 100644
--- a/advanced/odata.md
+++ b/advanced/odata.md
@@ -1187,6 +1187,7 @@ GET /Books?$apply=aggregate(stock with sum as stock) HTTP/1.1
 #### Currencies and Units of Measure
 
 If a property represents a monetary amount, it may have a related property that indicates the amount's *currency code*. Analogously, a property representing a measured quantity can be related to a *unit of measure*. To indicate that a property is a currency code or a unit of measure it can be annotated with the [Semantics Annotations](https://help.sap.com/docs/SAP_NETWEAVER_750/cc0c305d2fab47bd808adcad3ca7ee9d/fbcd3a59a94148f6adad80b9c97304ff.html) `@Semantics.currencyCode` or `@Semantics.unitOfMeasure`.
+The aggregation method (typically, sum) is specified with the `@Aggregation.default` annotation.
 
 ```cds
 @Aggregation.CustomAggregate#amount   : 'Edm.Decimal'
@@ -1195,6 +1196,7 @@ entity Sales {
     key id        : GUID;
         productId : GUID;
         @Semantics.amount.currencyCode: 'currency'
+        @Aggregation.default: #SUM
         amount    : Decimal(10,2);
         @Semantics.currencyCode
         currency  : String(3);