huaxingao commented on a change in pull request #28220:
[SPARK-31390][SQL][DOCS] Document Window Function in SQL Syntax Section
URL: https://github.com/apache/spark/pull/28220#discussion_r409220082
##########
File path: docs/sql-ref-syntax-qry-window.md
##########
@@ -19,4 +19,208 @@ license: |
limitations under the License.
---
-**This page is under construction**
+### Description
+
+Window functions operate on a group of rows, referred to as a window, and
calculate an aggregated value for each row based on the specified window.
Window functions are useful for processing tasks such as calculating a moving
average, computing a cumulative statistic, or accessing the value of rows given
the relative position of the current row. Spark SQL supports three types of
window functions:
+
+ * Ranking Functions
+ * Analytic Functions
+ * Aggregate Functions
+
+### Syntax
+
+{% highlight sql %}
+window_function OVER ( [ partition_spec ] order_spec [ window_frame ] )
+{% endhighlight %}
+
+### Parameters
+
+<dl>
+ <dt><code><em>window_function</em></code></dt>
+ <dd>
+ <ul>
+ <li> Ranking Functions </li>
+ <br>
+ <b>Syntax:</b>
+ <code>
+ RANK | DENSE_RANK | PERCENT_RANK | NTILE | ROW_NUMBER
+ </code>
+ </ul>
+ <ul>
+ <li> Analytic Functions </li>
+ <br>
+ <b>Syntax:</b>
+ <code>
+ CUME_DIST | LAG | LEAD
+ </code>
+ </ul>
+ <ul>
+ <li> Aggregate Functions </li>
+ <br>
+ <b>Syntax:</b>
+ <code>
+ MAX | MIN | COUNT | SUM | AVG | ...
+ </code>
+ <br>
+ Please refer <a href="api/sql/">here</a> for a complete list of Spark
Aggregate Functions.
Review comment:
I will put ```sql-ref-functions-builtin.html``` as the link for Built-in
Function document. It's broken now but will work after your PR is in.
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
With regards,
Apache Git Services
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
