问题
(Forgive me since I am not use to posting here. Will do my best)
I am working on an iOS application that will be using a pre-populated database. In my workspace, I have a project for the iOS app and a separate command line tool project to populate the database. I have dragged the database file from the "/Library/Application Support" folder into my iOS project (without using the "Copy Items If Needed"). So when there is a change in the data or additional data is required, I can just run the command line tool to pre-populate the data. From there I will remove the app from the simulator and do a clean. When I run the app, I would think everything would be ok.
It was driving me crazy for the longest but sometimes, I don't see the changes reflected after I remove the app, clean the project and then run. It seems the only way I can get this to work is, after I run the command line tool to pre-populate the database, I have to open the database file using Base, SQLiteStudio or Firefox's sqlite add-on. Once I do that, it seems to work.
When I look in finder, I do see the files .sqlite, sqlite-shm and sqlite-wal. Before opening the database file, I see that the wal file is the biggest (for now it's 2mb). Once I open the file using Base for example, and then close it, the sqlite file is now 2mb.
When the command line is about to finish, I have tried running PRAGMA statements on the file (vacuum, wal-checkpoint) but those did not work. What am I missing here. I also tried using NSManagedObjectContext.MR_defaultContext.saveToPersistentStoreAndWait
I am using the following code to setup and save.
MagicalRecord.setupCoreDataStackWithAutoMigratingSqliteStoreNamed("callithome.sqlite")
MagicalRecord.saveUsingCurrentThreadContextWithBlockAndWait({(context)->Void in
println("Data saved, I hope")})
MagicalRecord.cleanUp()
Any help would be appreciated
回答1:
You need to enable the DELETE pragma mode for your sqlite store. This will not create the -wal and -shm files. This will make it easier for you to have a single file for use at your pre-populated data store. You will need to use MagicalRecord 3.0 with some of the extra abilities to add custom options to your stores if you'd like o go that route. However, you can still add a store to a coordinator and have that store configured with the proper pragma option as well. That is, MagicalRecord is not necessary if you use normal Core Data.
来源：https://stackoverflow.com/questions/26498359/using-magicalrecord-to-prepopulate-a-database-swift-wal-journal-created-how