From 640f63b959f936ac142ce429262ffc3db4536619 Mon Sep 17 00:00:00 2001
From: vidmantas zemleris <vidmantas@vinted.com>
Date: Mon, 11 May 2015 22:29:24 -0700
Subject: [PATCH] [SPARK-6994][SQL] Update docs for fetching Row fields by name
add docs for https://issues.apache.org/jira/browse/SPARK-6994
Author: vidmantas zemleris <vidmantas@vinted.com>
Closes #6030 from vidma/docs/row-with-named-fields and squashes the following commits:
241b401 [vidmantas zemleris] [SPARK-6994][SQL] Update docs for fetching Row fields by name
---
docs/sql-programming-guide.md | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/docs/sql-programming-guide.md b/docs/sql-programming-guide.md
index 6b7b867ea6..78b8e8ad51 100644
--- a/docs/sql-programming-guide.md
+++ b/docs/sql-programming-guide.md
@@ -367,11 +367,18 @@ val people = sc.textFile("examples/src/main/resources/people.txt").map(_.split("
people.registerTempTable("people")
// SQL statements can be run by using the sql methods provided by sqlContext.
-val teenagers = sqlContext.sql("SELECT name FROM people WHERE age >= 13 AND age <= 19")
+val teenagers = sqlContext.sql("SELECT name, age FROM people WHERE age >= 13 AND age <= 19")
// The results of SQL queries are DataFrames and support all the normal RDD operations.
-// The columns of a row in the result can be accessed by ordinal.
+// The columns of a row in the result can be accessed by field index:
teenagers.map(t => "Name: " + t(0)).collect().foreach(println)
+
+// or by field name:
+teenagers.map(t => "Name: " + t.getAs[String]("name")).collect().foreach(println)
+
+// row.getValuesMap[T] retrieves multiple columns at once into a Map[String, T]
+teenagers.map(_.getValuesMap[Any](List("name", "age"))).collect().foreach(println)
+// Map("name" -> "Justin", "age" -> 19)
{% endhighlight %}
</div>
@@ -538,7 +545,7 @@ peopleDataFrame.registerTempTable("people")
val results = sqlContext.sql("SELECT name FROM people")
// The results of SQL queries are DataFrames and support all the normal RDD operations.
-// The columns of a row in the result can be accessed by ordinal.
+// The columns of a row in the result can be accessed by field index or by field name.
results.map(t => "Name: " + t(0)).collect().foreach(println)
{% endhighlight %}
--
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