Github user chenliang613 commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/2576#discussion_r206480055
--- Diff: docs/datamap/preaggregate-datamap-guide.md ---
@@ -7,6 +24,7 @@
* [Querying Data](#querying-data)
* [Compaction](#compacting-pre-aggregate-tables)
* [Data Management](#data-management-with-pre-aggregate-tables)
+* [Limitations](#Limitations)
--- End diff --
Why need to add this item---
