Optimize code

beliefer · beliefer · commit 1c0e82ba0ab9 · 2020-10-28T10:15:27.000+08:00
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala
@@ -62,7 +62,7 @@ import org.apache.spark.sql.types.{CalendarIntervalType, DateType, IntegerType,
  *     1. [[FrameLessOffsetWindowFunction]] returns the value of the input column offset by a number
  *        of rows according to the current row.
  *     2. [[UnboundedOffsetWindowFunctionFrame]] and [[UnboundedPrecedingOffsetWindowFunctionFrame]]
- *       returns the value of the input column offset by a number of rows within the partition.
+ *       returns the value of the input column offset by a number of rows within the frame.
  *
  * Different frame boundaries can be used in Growing, Shrinking and Moving frames. A frame
  * boundary can be either Row or Range based:
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowFunctionFrame.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowFunctionFrame.scala
@@ -178,7 +178,7 @@ class FrameLessOffsetWindowFunctionFrame(
 /**
  * The unbounded offset window frame is an internal window frame just used to optimize the
  * performance for the window function that returns the value of the input column offset
- * by a number of rows within the partition and has specified ROWS BETWEEN UNBOUNDED PRECEDING
+ * by a number of rows within the frame and has specified ROWS BETWEEN UNBOUNDED PRECEDING
  * AND UNBOUNDED FOLLOWING. The internal window frame is not a popular window frame cannot be
  * specified and used directly by the users.
  * The unbounded offset window frame calculates frames containing NTH_VALUE statements.
@@ -220,7 +220,7 @@ class UnboundedOffsetWindowFunctionFrame(
 /**
  * The unbounded preceding offset window frame is an internal window frame just used to optimize
  * the performance for the window function that returns the value of the input column offset
- * by a number of rows within the partition and has specified ROWS BETWEEN UNBOUNDED PRECEDING
+ * by a number of rows within the frame and has specified ROWS BETWEEN UNBOUNDED PRECEDING
  * AND CURRENT ROW. The internal window frame is not a popular window frame cannot be specified
  * and used directly by the users.
  * The unbounded preceding offset window frame calculates frames containing NTH_VALUE statements.
@@ -248,7 +248,7 @@ class UnboundedPrecedingOffsetWindowFunctionFrame(
       if (inputIterator.hasNext) inputIterator.next()
       inputIndex += 1
     }
-    if (inputIndex >= 0 && inputIndex < input.length) {
+    if (inputIndex < input.length) {
       selectedRow = WindowFunctionFrame.getNextOrNull(inputIterator)
     }
   }

Original file line number	Diff line number	Diff line change
`@@ -62,7 +62,7 @@ import org.apache.spark.sql.types.{CalendarIntervalType, DateType, IntegerType,`
`62`	`62`	`* 1. [[FrameLessOffsetWindowFunction]] returns the value of the input column offset by a number`
`63`	`63`	`* of rows according to the current row.`
`64`	`64`	`* 2. [[UnboundedOffsetWindowFunctionFrame]] and [[UnboundedPrecedingOffsetWindowFunctionFrame]]`
`65`		`- * returns the value of the input column offset by a number of rows within the partition.`
	`65`	`+ * returns the value of the input column offset by a number of rows within the frame.`
`66`	`66`	`*`
`67`	`67`	`* Different frame boundaries can be used in Growing, Shrinking and Moving frames. A frame`
`68`	`68`	`* boundary can be either Row or Range based:`