[GitHub] wdick commented on a change in pull request #23362: [MINOR][DOCS]Document subquery support for the `table` parameter

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wdick commented on a change in pull request #23362: [MINOR][DOCS]Document subquery support for the `table` parameter
URL: https://github.com/apache/spark/pull/23362#discussion_r243596762
 
 

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 File path: sql/core/src/main/scala/org/apache/spark/sql/DataFrameReader.scala
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 @@ -235,6 +235,19 @@ class DataFrameReader private[sql](sparkSession: SparkSession) extends Logging {
    * Construct a `DataFrame` representing the database table accessible via JDBC URL
    * url named table and connection properties.
    *
+   * The `table` parameter can be based on a derived table, which is generated within the scope of
+   * a query FROM clause. For example, you could use this subquery as `table:
+   * {{{
+   *    "(SELECT * FROM customers WHERE ...) AS tmp"
+   * }}}
 
 Review comment:
   Perfect! This is a part of the documentation, that I seam to have missed.

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