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Author: dongjoon-hyun

sql/core/src/main/scala/org/apache/spark/sql/catalyst/SQLBuilder.scala

@@ -138,6 +138,8 @@ class SQLBuilder private (
     case g: Generate =>
       generateToSQL(g)
 
+    // This prevents a pattern of `((...) AS gen_subquery_0 LIMIT 1)` which does not work.
+    // For example, `SELECT * FROM (SELECT id FROM tbl TABLESAMPLE (2 ROWS))` makes this plan.
     case Limit(limitExpr, child: SubqueryAlias) =>
       s"${toSQL(child)} LIMIT ${limitExpr.sql}"