diff --git a/docs/structured-streaming-programming-guide.md b/docs/structured-streaming-programming-guide.md
index 3f89111687..18dfbec794 100644
--- a/docs/structured-streaming-programming-guide.md
+++ b/docs/structured-streaming-programming-guide.md
@@ -1820,6 +1820,8 @@ Some of them are as follows.
 
 - Distinct operations on streaming Datasets are not supported.
 
+- Deduplication operation is not supported after aggregation on a streaming Datasets.
+
 - Sorting operations are supported on streaming Datasets only after an aggregation and in Complete Output Mode.
 
 - Few types of outer joins on streaming Datasets are not supported. See the
@@ -3464,7 +3466,7 @@ the effect of the change is not well-defined. For all of them:
 
   - *Streaming aggregation*: For example, `sdf.groupBy("a").agg(...)`. Any change in number or type of grouping keys or aggregates is not allowed.
 
-  - *Streaming deduplication*: For example, `sdf.dropDuplicates("a")`. Any change in number or type of grouping keys or aggregates is not allowed.
+  - *Streaming deduplication*: For example, `sdf.dropDuplicates("a")`. Any change in number or type of deduplicating columns is not allowed.
 
   - *Stream-stream join*: For example, `sdf1.join(sdf2, ...)` (i.e. both inputs are generated with `sparkSession.readStream`). Changes
     in the schema or equi-joining columns are not allowed. Changes in join type (outer or inner) are not allowed. Other changes in the join condition are ill-defined.