Merge pull request #216153 from seesharprun/cosmos-timestamp-example

Cosmos DB | Update timestamp query article

Author: BCS2022

articles/cosmos-db/nosql/query/timestamptodatetime.md

@@ -5,12 +5,14 @@ author: seesharprun
 ms.service: cosmos-db
 ms.subservice: nosql
 ms.topic: conceptual
-ms.date: 08/18/2020
+ms.date: 10/27/2022
 ms.author: sidandrews
 ms.reviewer: jucocchi
 ms.custom: query-reference, ignite-2022
 ---
+
 # TimestampToDateTime (Azure Cosmos DB)
+
 [!INCLUDE[NoSQL](../../includes/appliesto-nosql.md)]
 
 Converts the specified timestamp value to a DateTime.
@@ -23,7 +25,7 @@ TimestampToDateTime (<Timestamp>)
 
 ## Arguments
 
-*Timestamp*  
+### Timestamp
 
 A signed numeric value, the current number of milliseconds that have elapsed since the Unix epoch. In other words, the number of milliseconds that have elapsed since 00:00:00 Thursday, 1 January 1970.
 
@@ -43,27 +45,58 @@ Returns the UTC date and time ISO 8601 string value in the format `YYYY-MM-DDThh
 |.fffffff|seven-digit fractional seconds|
 |Z|UTC (Coordinated Universal Time) designator|
 
-  For more information on the ISO 8601 format, see [ISO_8601](https://en.wikipedia.org/wiki/ISO_8601)
+For more information on the ISO 8601 format, see [ISO_8601](https://en.wikipedia.org/wiki/ISO_8601)
 
 ## Remarks
 
 TimestampToDateTime will return `undefined` if the timestamp value specified is invalid.
 
 ## Examples
 
-The following example converts the timestamp to a DateTime:
+The following example converts the value `1,594,227,912,345` from milliseconds to a date and time of **July 8, 2020, 5:05 PM UTC**.
 
 ```sql
 SELECT TimestampToDateTime(1594227912345) AS DateTime
 ```
 
 ```json
 [
-    {
-        "DateTime": "2020-07-08T17:05:12.3450000Z"
-    }
+  {
+    "DateTime": "2020-07-08T17:05:12.3450000Z"
+  }
+]
+```
+
+This next example uses the timestamp from an existing item in a container. The item's timestamp is expressed in seconds.
+
+```json
+{
+  "id": "8cc56bd4-5b8d-450b-a576-449836171398",
+  "type": "reading",
+  "data": "temperature",
+  "value": 35.726545156,
+  "_ts": 1605862991
+}
+```
+
+To use the `_ts` value, you must multiply the value by 1,000 since the timestamp is expressed in seconds.
+
+```sql
+SELECT 
+  TimestampToDateTime(r._ts * 1000) AS timestamp, 
+  r.id 
+FROM 
+  readings r
+```
+
+```json
+[
+  {
+    "timestamp": "2020-11-20T09:03:11.0000000Z",
+    "id": "8cc56bd4-5b8d-450b-a576-449836171398"
+  }
 ]
-```  
+```
 
 ## Next steps