# Implementing Incremental Reflections in Dremio for Optimized Query Scanning

**URL:** <https://community.dremio.com/t/implementing-incremental-reflections-in-dremio-for-optimized-query-scanning/12611>\
**Category:** Uncategorized\
**Created:** [December 16, 2024, 10:12am UTC](https://community.dremio.com/t/implementing-incremental-reflections-in-dremio-for-optimized-query-scanning/12611 "2024-12-16T10:12:09Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![JoiceJacob](https://sea2.discourse-cdn.com/flex020/user_avatar/community.dremio.com/joicejacob/32/5715_2.png) [@JoiceJacob](https://community.dremio.com/u/JoiceJacob)\
**Post date:** [December 16, 2024, 10:12am UTC](https://community.dremio.com/t/implementing-incremental-reflections-in-dremio-for-optimized-query-scanning/12611/1 "2024-12-16T10:12:09Z")

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I am trying to implement incremental reflection in Dremio for a specific use case.

I created a view on the table using the following query:

> SELECT ID, Cust\_Sub\_Id, Msisdn, Event\_Date, Revenue  
> FROM mysql16.EDA.“dremio\_reflection\_test”.

A ROW REFLECTION was then created on this view.

Next, I executed the query:

> SELECT Cust\_Sub\_Id, Msisdn, Revenue  
> FROM “Reflection R&D”.“VDS 001”.

Afterward, I inserted 2-3 new rows into the table and refreshed the reflection. Upon re-executing the same query:

> SELECT Cust\_Sub\_Id, Msisdn, Revenue  
> FROM “Reflection R&D”.“VDS 001”.

I expected the system to scan only the newly added rows in the table. However, when I checked the Rows Scanned section in the job details, I observed that all rows were being scanned instead of just the new ones.

Does Dremio support scanning only newly added rows in this scenario? If so, how can I achieve incremental reflection based on this use case?

Also I have an another doubt that In Dremio, that does the reflection refresh process only add newly inserted rows to the snapshot, or does it take a snapshot of the entire table again after each refresh?

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<div class="post-metadata">

**Author:** ![balaji.ramaswamy](https://sea2.discourse-cdn.com/flex020/user_avatar/community.dremio.com/balaji.ramaswamy/32/843_2.png) [@balaji.ramaswamy](https://community.dremio.com/u/balaji.ramaswamy)\
**Post date:** [December 18, 2024, 9:13pm UTC](https://community.dremio.com/t/implementing-incremental-reflections-in-dremio-for-optimized-query-scanning/12611/2 "2024-12-18T21:13:08Z")

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@JoiceJacob Where is the data? Parquet or a RDBMS?

Can you please send me the below 2 profiles

- Full REFRESH REFLECTION
- Incremental refresh