Refresh Semantic Model with Import Mode

[Anonymous]

Hello everyone!

I’m having some difficulty understanding the following:

Task:

I want to migrate my model to Fabric with Import storage mode, while the connection is to an on-prem SQL database.

I’m using Tabular Editor and I’ve created two sets of models:

Model 1:

I migrated the model as it is to Fabric with Import storage mode, then I refreshed the model, and the data was loaded successfully. My model has partitions but without incremental refresh enabled. The refresh process in this scenario is quite fast.

However, according to the documentation, when using Import mode, all tables are re-imported each time a refresh occurs. But when I use the semantic link to verify if my data was reloaded, the last refresh time remains as the initial refresh time.

So my question is: What exactly happens when I refresh an Import mode model without incremental refresh? Are all the data deleted and re-imported, or are only the new partitions refreshed while the old ones remain untouched?

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Model 2:

For the second model, I deployed it with incremental refresh enabled, so it only refreshes the data for the last two months while archiving the data for the past four years.

In this case, when I initially refreshed the model, it took 5 hours to complete the refresh of all partitions. However, for subsequent refreshes, the process was much quicker. Using the semantic link, I can confirm that only the partitions for the last two months were refreshed, as expected.

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Summary:

To sum up, can anyone explain the difference between having a model with incremental refresh versus one using only Import mode? Specifically:

1. How are the refreshes executed in both cases?
2. How can I be sure which partitions are actually being refreshed?

Thank you for your insights!

[Akash_Varuna · Accepted solution]

Hi @Anonymous 

• Import Mode (No Incremental Refresh):

  • Refresh re-imports all data.
  • Slower for large models; may appear unchanged due to caching.

• Import Mode (With Incremental Refresh):

  • Only recent partitions (e.g., last 2 months) are refreshed.
  • Faster subsequent refreshes, as older data remains untouched.

Incremental refresh optimizes performance by targeting specific partitions, reducing refresh time for large datasets.

Plain Import mode re-imports data entirely, leading to longer refresh times for large models.
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Thanks In Advance