Github user keypointt commented on a diff in the pull request:
https://github.com/apache/spark/pull/14082#discussion_r70124885
--- Diff: examples/src/main/r/RSparkSQLExample.R ---
@@ -0,0 +1,198 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+library(SparkR)
+
+# $example on:init_session$
+sparkR.session()
+# $example off:init_session$
+
+
+# $example on:create_DataFrames$
+df <- read.json("examples/src/main/resources/people.json")
+
+# Displays the content of the DataFrame
+head(df)
+
+# Another method to print the first few rows and optionally truncate the
printing of long values
+head(df)
+# $example off:create_DataFrames$
+
+
+# $example on:dataframe_operations$
+# Create the DataFrame
+df <- read.json("examples/src/main/resources/people.json")
+
+# Show the content of the DataFrame
+head(df)
+## age name
+## null Michael
+## 30 Andy
+## 19 Justin
+
+# Print the schema in a tree format
+printSchema(df)
+## root
+## |-- age: long (nullable = true)
+## |-- name: string (nullable = true)
+
+# Select only the "name" column
+head(select(df, "name"))
+## name
+## Michael
+## Andy
+## Justin
+
+# Select everybody, but increment the age by 1
+head(select(df, df$name, df$age + 1))
+## name (age + 1)
+## Michael null
+## Andy 31
+## Justin 20
+
+# Select people older than 21
+head(where(df, df$age > 21))
+## age name
+## 30 Andy
+
+# Count people by age
+head(count(groupBy(df, "age")))
+## age count
+## null 1
+## 19 1
+## 30 1
+# $example off:dataframe_operations$
+
+
+# Create a DataFrame from json file
+path <- file.path(Sys.getenv("SPARK_HOME"),
"examples/src/main/resources/people.json")
+peopleDF <- read.json(path)
+# Register this DataFrame as a table.
+createOrReplaceTempView(peopleDF, "table")
+# $example on:sql_query$
+df <- sql("SELECT * FROM table")
+# $example off:sql_query$
+
+
+# $example on:source_parquet$
+df <- read.df("examples/src/main/resources/users.parquet")
+write.df(select(df, "name", "favorite_color"), "namesAndFavColors.parquet")
+# $example off:source_parquet$
+
+
+# $example on:source_json$
+df <- read.df("examples/src/main/resources/people.json", "json")
+write.df(select(df, "name", "age"), "namesAndAges.parquet", "parquet")
+# $example off:source_json$
+
+
+# $example on:direct_query$
+df <- sql("SELECT * FROM
parquet.`examples/src/main/resources/users.parquet`")
+# $example off:direct_query$
+
+
+# $example on:load_programmatically$
+df <- read.df("examples/src/main/resources/people.json", "json")
+
+# SparkDataFrame can be saved as Parquet files, maintaining the schema
information.
+write.parquet(df, "people.parquet")
+
+# Read in the Parquet file created above. Parquet files are
self-describing so the schema is preserved.
+# The result of loading a parquet file is also a DataFrame.
+parquetFile <- read.parquet("people.parquet")
+
+# Parquet files can also be used to create a temporary view and then used
in SQL statements.
+createOrReplaceTempView(parquetFile, "parquetFile")
+teenagers <- sql("SELECT name FROM parquetFile WHERE age >= 13 AND age <=
19")
+head(teenagers)
+## name
+## 1 Justin
+
--- End diff --
sure
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