Load an SQLite Database preloaded into Core Data - ios

I have a database preloaded in SQLite: "BenedictusCoreData.sqlite".
I add it to the project in XCode.
I modify the BenedictusCoreData.xcdatamodeld to create the entities and attributes with the same name and type as the tables and columns of my sqlite preoloaded.
I run the app in the simulator without writing any additional code. I print the main bundle path and go to the sandbox of the application. And inside /Library/Application Support/ I find the three files: .sqlite .sqlite-shm .sqlite-wal
I open the .sqlite and obviously it is empty, however Xcode has created the tables and the columns with capital letters, adding "Z" to the tablenames and "Z" to the column names, appart from adding new tables "Z_METADATA" "Z_MODELCACHE", "Z_PRIMARYKEY".
At this point, I assume that it is not a good idea just to copy my sqlite from the bundle into the "Application Support" folder and rewrite the file, because the structure is totally different.
So I am lost about how to proceed in order to copy a sqlite preloaded database into CoreData the first time you open the app.
May be you can help me.

In the appDelegate you can change the default .xcdatamodel name to the one you added. Then xcode will load your preloaded data .sqlite file instead of the default one. You should search it up there's tutorials on this

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A better option would be to keep a "canned" sqlite file in your app bundle and check for the existence of the SQLite file in your documents directory. If the file does not exist, copy the canned data from the app bundle to your documents directory.
That will skip the entire parsing logic and will allow your application to launch faster.
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Thanks
for it, you need to modify database by using programmatically. Means, if you want to create/add new table in database then you need to add code like Create Table.... In this case, you can't use predefine database in code.
But if you want to use database instead of writing code, then you need to rename your database and copy all old database data to new database programmatically.
Thanks

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