here is the content i referred to
I tried everything, concluded this is the best, especially if you are coming from excel, you need to "trust that your data is not lost - and btw, once you make the import, you can copy both old and new data in a separate excel to verify columns such as if ColumnA in excel equals to ColumnA in Dataverse, then, ok, otherwise, error)
1. Create your Dataverse table, add an autonumber column to the table so you can see rows in order assending..
2. Create another dummy column to delete later but will use temporarily
3. Set the "only" Required column, which is Name, to Optional
4. Create a View to look like the Excel Sheet you have, just add the 2 more columns Autonumber and Dummy
5. Create your own model-driven app for that Table
6. From within the Model Driven in run mode, Click export to Excel, then Open in Excel online. You will see a blank Excel Sheet as no data there yet
7. Fill in the Dummy Column with anything, just drag to create more rows as much as you have in your Excel
8. Hit Save, wait until the Dataverse creates your rows - you can track this after you hit the Save.
9. Now your rows as created, just be curious to check their autonumber - you will see - or must see - they are sorted ascendingly as intended
10. Click export to Excel, then Open in Excel online again, you will see your Dataverse as blank Excel sheet. Confidently copy from your old excel and paste into the Dataverse Excel.
10. Notes:
A. Your Old Excel must be formatted properly for such Date need to be m/d/yy for instance - make small tests before you go ahead with the complete data
B. The above covers a single Excel sheet migration. if you intend to create a relational database - which is intended i guess, then create your 2 dataverse tables, import your data as shown, then in the child table, create a TEXT column to show the NAME of the parent table RAW, then create a view with both parent NAME (which comes form parent table) and the TEXT parent raw name, then from inside the excel online, copy the test PARENT name to the actual parent NAME, give it sometime until done, magic!
