diff --git a/documentation/reference/sql/sample-by.md b/documentation/reference/sql/sample-by.md
index eceb0a97f..736d5d3c5 100644
--- a/documentation/reference/sql/sample-by.md
+++ b/documentation/reference/sql/sample-by.md
@@ -50,6 +50,7 @@ Where the unit for sampled groups may be one of the following:
 | `m`  | minute      |
 | `h`  | hour        |
 | `d`  | day         |
+| `w`  | week        |
 | `M`  | month       |
 | `y`  | year        |