# TiDB Course 302 Potential Non-Standard Narratives
+ 2022-05-05 19:50:17.838763

| Risk | Suggestion | Filename:Instance |
| :-- | :-- | :-- |
| federated index | composite index | chapter-20/23.md:Judging from the final 712 row records, creating a federated index can significantly reduce the amount of data scanned and further improve performance. In cases where the performance is already meeting the business requirements, there is an additional cost for federated indexes to be tried later. |
| point check | point query | chapter-08/09.md:- If it is a non-point check, that is, when request by the Coprocessor, the following will be done,chapter-16/04.md:- Pre Proces is mainly optimized for the case of point get. If it is a point check, the optimization process will be skipped and pushed down directly to the SQL executor,chapter-16/07.md:- The optimization method of the check itself is relatively single. Generally, the point check is optimized by index, and there is no need for logical optimization or physical optimization |