[GitHub] [spark] cloud-fan commented on a diff in pull request #36295: [SPARK-38978][SQL] DS V2 supports push down OFFSET operator

[GitBox <gi...@apache.org>]

cloud-fan commented on code in PR #36295:
URL: https://github.com/apache/spark/pull/36295#discussion_r902304551


##########
sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/jdbc/JDBCScanBuilder.scala:
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@@ -139,6 +142,25 @@ case class JDBCScanBuilder(
     false
   }
 
+  override def pushOffset(offset: Int): Boolean = {
+    if (jdbcOptions.pushDownOffset && !isPartiallyPushed) {
+      // We pushing down offset when data source have only one partition.
+      // There are some push down path.

Review Comment:
   We can make the comment much simpler:
   ```
   Spark pushes down LIMIT first, then OFFSET. In SQL statements, OFFSET is applied before
   LIMIT. Here we need to adjust the LIMIT value to match SQL statements.
   ```



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