function article

Author: bwren

articles/azure-monitor/toc.yml

@@ -690,6 +690,8 @@
           href: ../log-analytics/query-language/advanced-query-writing.md?toc=/azure/azure-monitor/toc.json
         - name: Charts and diagrams
           href: ../log-analytics/query-language/charts.md?toc=/azure/azure-monitor/toc.json
+        - name: Functions
+          href: ../log-analytics/query-language/functions.md?toc=/azure/azure-monitor/toc.json
       - name: Cheatsheets
         items:
         - name: SQL

articles/log-analytics/query-language/functions.md

@@ -1,6 +1,6 @@
 ---
 title: Functions Azure Log Analytics | Microsoft Docs
-description: This article provides a tutorial for using the Analytics portal to write queries in Log Analytics.
+description: This article describes how to use functions to call a query from another query in Log Analytics.
 services: log-analytics
 documentationcenter: ''
 author: bwren
@@ -12,7 +12,7 @@ ms.workload: na
 ms.tgt_pltfrm: na
 ms.devlang: na
 ms.topic: conceptual
-ms.date: 08/16/2018
+ms.date: 11/15/2018
 ms.author: bwren
 ms.component: na
 ---
@@ -25,8 +25,31 @@ ms.component: na
 
 [!INCLUDE [log-analytics-demo-environment](../../../includes/log-analytics-demo-environment.md)]
 
-## Functions
-You can save a query with a function alias so it can be referenced by other queries. For example, the following standard query returns all missing security updates reported in the last day:
+> [!NOTE]
+> Saving a function is possible in Log Analytics queries, but currently not for Application Insights queries.
+
+
+To use a Log Analytics query with another query you can save it as a function. This allows you to simplify complex queries by breaking them into parts and allows you to reuse common code with multiple queries.
+
+> [!NOTE]
+> A function in Log Analytics cannot contain another function.
+
+## Create a function
+
+Create a function in the Azure portal by clicking **Save** and then providing the information in the following table.
+
+| Setting | Description |
+|:---|:---|
+| Name           | Display name for the query in **Query explorer**. |
+| Save as        | Function |
+| Function Alias | Short name to use the function in other queries. May not contain spaces and must be unique. |
+| Category       | A category to organize saved queries and functions in **Query explorer**. |
+
+## Use a function
+Use a function by including its alias in another query. It can be used like any other table.
+
+## Example
+The following sample query returns all missing security updates reported in the last day:
 
 ```Kusto
 Update
@@ -35,18 +58,14 @@ Update
 | where UpdateState == "Needed"
 ```
 
-You can save this query as a function and give it an alias such as _security_updates_last_day_. Then you can use it in another query to search for SQL-related needed security updates:
+Save this query as a function with the alias _security_updates_last_day_. 
+
+Create another to search for SQL-related needed security updates:
 
 ```Kusto
 security_updates_last_day | where Title contains "SQL"
 ```
 
-To save a query as a function, select the **Save** button in the portal and change **Save as** to _Function_. The function alias can contain letters, digits, or underscores but must start with a letter or an underscore.
-
-> [!NOTE]
-> Saving a function is possible in Log Analytics queries, but currently not for Application Insights queries.
-
-
 ## Next steps
 See other lessons for using the Log Analytics query language: