SPARK-6988 : Fix documentation regarding DataFrames using the Java API
This patch includes : * adding how to use map after an sql query using javaRDD * fixing the first few java examples that were written in Scala Thank you for your time, Olivier. Author: Olivier Girardot <o.girardot@lateral-thoughts.com> Closes #5564 from ogirardot/branch-1.3 and squashes the following commits: 9f8d60e [Olivier Girardot] SPARK-6988 : Fix documentation regarding DataFrames using the Java API (cherry picked from commit 6b528dc139da594ef2e651d84bd91fe0f738a39d) Signed-off-by: Reynold Xin <rxin@databricks.com>
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@ -193,8 +193,8 @@ df.groupBy("age").count().show()
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<div data-lang="java" markdown="1">
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{% highlight java %}
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val sc: JavaSparkContext // An existing SparkContext.
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val sqlContext = new org.apache.spark.sql.SQLContext(sc)
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JavaSparkContext sc // An existing SparkContext.
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SQLContext sqlContext = new org.apache.spark.sql.SQLContext(sc)
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// Create the DataFrame
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DataFrame df = sqlContext.jsonFile("examples/src/main/resources/people.json");
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@ -308,8 +308,8 @@ val df = sqlContext.sql("SELECT * FROM table")
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<div data-lang="java" markdown="1">
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{% highlight java %}
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val sqlContext = ... // An existing SQLContext
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val df = sqlContext.sql("SELECT * FROM table")
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SQLContext sqlContext = ... // An existing SQLContext
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DataFrame df = sqlContext.sql("SELECT * FROM table")
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{% endhighlight %}
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</div>
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@ -435,7 +435,7 @@ DataFrame teenagers = sqlContext.sql("SELECT name FROM people WHERE age >= 13 AN
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// The results of SQL queries are DataFrames and support all the normal RDD operations.
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// The columns of a row in the result can be accessed by ordinal.
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List<String> teenagerNames = teenagers.map(new Function<Row, String>() {
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List<String> teenagerNames = teenagers.javaRDD().map(new Function<Row, String>() {
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public String call(Row row) {
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return "Name: " + row.getString(0);
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}
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@ -599,7 +599,7 @@ DataFrame results = sqlContext.sql("SELECT name FROM people");
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// The results of SQL queries are DataFrames and support all the normal RDD operations.
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// The columns of a row in the result can be accessed by ordinal.
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List<String> names = results.map(new Function<Row, String>() {
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List<String> names = results.javaRDD().map(new Function<Row, String>() {
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public String call(Row row) {
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return "Name: " + row.getString(0);
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}
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@ -860,7 +860,7 @@ DataFrame parquetFile = sqlContext.parquetFile("people.parquet");
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//Parquet files can also be registered as tables and then used in SQL statements.
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parquetFile.registerTempTable("parquetFile");
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DataFrame teenagers = sqlContext.sql("SELECT name FROM parquetFile WHERE age >= 13 AND age <= 19");
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List<String> teenagerNames = teenagers.map(new Function<Row, String>() {
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List<String> teenagerNames = teenagers.javaRDD().map(new Function<Row, String>() {
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public String call(Row row) {
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return "Name: " + row.getString(0);
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}
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