[SQL] Minor doc update: Add an example in DataFrameReader.schema

## What changes were proposed in this pull request? This patch adds a small example to the schema string definition of schema function. It isn't obvious how to use it, so an example would be useful. ## How was this patch tested? N/A - doc only. Author: Reynold Xin <[email protected]> Closes #20491 from rxin/schema-doc.
apache · Feb 3, 2018 · 3ff83ad · 3ff83ad
1 parent eaf35de
commit 3ff83ad
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diff --git a/sql/core/src/main/scala/org/apache/spark/sql/DataFrameReader.scala b/sql/core/src/main/scala/org/apache/spark/sql/DataFrameReader.scala
@@ -74,6 +74,10 @@ class DataFrameReader private[sql](sparkSession: SparkSession) extends Logging {
    * infer the input schema automatically from data. By specifying the schema here, the underlying
    * data source can skip the schema inference step, and thus speed up data loading.
    *
+   * {{{
+   *   spark.read.schema("a INT, b STRING, c DOUBLE").csv("test.csv")
+   * }}}
+   *
    * @since 2.3.0
    */
   def schema(schemaString: String): DataFrameReader = {