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datafusion/sqllogictest/test_files/limit.slt

@@ -569,6 +569,7 @@ drop table data;
 
 ####################
 # Test issue: limit pushdown with offsets
+# Ensure the offset is not lost: https://github.com/apache/datafusion/issues/12423
 ####################
 
 statement ok
@@ -617,6 +618,7 @@ SELECT b, sum(a) FROM ordered_table GROUP BY b order by b desc OFFSET 1 LIMIT 2;
 1 0
 
 # Applying offset & limit when multiple streams from groupby
+# the plan must still have a global limit to apply the offset
 query TT
 EXPLAIN SELECT b, sum(a) FROM ordered_table GROUP BY b order by b desc OFFSET 1 LIMIT 2;
 ----
@@ -637,6 +639,7 @@ physical_plan
 09)----------------CsvExec: file_groups={1 group: [[WORKSPACE_ROOT/datafusion/core/tests/data/window_2.csv]]}, projection=[a, b], has_header=true
 
 # Applying offset & limit when multiple streams from union
+# the plan must still have a global limit to apply the offset
 query TT
 explain select * FROM (
   select c FROM ordered_table
@@ -665,7 +668,7 @@ physical_plan
 10)----------RepartitionExec: partitioning=RoundRobinBatch(4), input_partitions=1
 11)------------CsvExec: file_groups={1 group: [[WORKSPACE_ROOT/datafusion/core/tests/data/window_2.csv]]}, projection=[d], has_header=true
 
-# ApplyingmLIMIT & OFFSET to subquery.
+# Applying LIMIT & OFFSET to subquery.
 query III
 select t1.b, c, c2 FROM (
   select b, c FROM ordered_table ORDER BY b desc, c desc OFFSET 1 LIMIT 4