Ignore field when batch.update

[lsaudon]

Is it possible to ignore a field when updating a row?

[North101]

Use a Companion. One is generated for each table.

TodosCompanion(
  category: Value(target.id),
);

You need to wrap each value in Value(<value>) and if you don't want to update the value (or use the default for inserts) either don't include the field or do:

TodosCompanion(
  category: Value.absent(),
);

[MathiasCochet]

If category is not set as nullable it gets the "required" annotation. When updating the column using the companion object and setting category to Value.absent() I get an error saying category is required. But I just want to set the category once and never update it. How do I go about doing that ?

[simolus3]

You should be able to keep the category absent for updates. Could you post the error and the code you've used to create the companion?

[spauldhaliwal]

@simolus3 I'm having this error too. I'll paste the companion creation, insert, and error below.

Column definition:

TextColumn get name => text()();

Companion creation:

final profile =  ProfilesCompanion(
                                profileId: Value(profileId),
                                name: name != null ? Value(name) : const Value.absent(),
                                // etc...
                        );

INSERT function

into(profiles).insertOnConflictUpdate(
      profile,
    )

Error:

12:39:13.009  E  [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: InvalidDataException: Sorry, ProfilesCompanion(profileId: Value(1), name: Value.absent(), imageUri: Value.absent(), mergeWatchNextAndWatchlist: Value.absent(), mergeNewMoviesAndTelevision: Value.absent(), hideWatchNext: Value.absent(), movieSpotlightListId: Value.absent(), televisionSpotlightListId: Value.absent(), showNonTvApps: Value.absent(), keepAppRecommendationsSeparate: Value.absent(), maxContentRating: Value.absent(), homeViewMode: Value(HomeViewMode.wallpaper), homeViewHintMode: Value.absent(), showHomeFeedHint: Value.absent(), wallpaperPath: Value.absent(), wallpaperBlurHash: Value.absent(), wallpaperBrightness: Value.absent(), feedHintVisibility: Value.absent(), showWallpaperInHomeFeed: Value.absent(), showWallpaperInNavigationMenu: Value.absent(), showWallpaperInMediaLibraries: Value.absent(), showWallpaperInAppLibrary: Value.absent(), showWallpaperInAppPeek: Value.absent(), clockMode: Value.absent(), defaultOpenAction: Value.absent(), showAppPeek: Value.absent(), saveState: Value.absent(), appPeekImmersiveMode: Value.absent(), showWeather: Value.absent(), weatherTemperatureScale: Value.absent(), playNavigationSounds: Value.absent(), showMovieTab: Value.absent(), showTelevisionTab: Value.absent(), watchNextNaturalOrder: Value.absent(), showMediaWatchedIndicators: Value.absent(), showMediaStatusIndicators: Value.absent(), showMediaTrendingIndicators: Value.absent()) cannot be used for that because: 
                 • name: This value was required, but isn't present
                 
                 #0      VerificationContext.throwIfInvalid (package:drift/src/runtime/data_verification.dart:74:5)
                 #1      InsertStatement._validateIntegrity (package:drift/src/runtime/query_builder/statements/insert.dart:379:51)
                 #2      InsertStatement.createContext (package:drift/src/runtime/query_builder/statements/insert.dart:210:5)
                 #3      InsertStatement.insert (package:drift/src/runtime/query_builder/statements/insert.dart:70:17)
                 #4      InsertStatement.insertOnConflictUpdate (package:drift/src/runtime/query_builder/statements/insert.dart:201:12)
                 #5      ProfilesDao.updateProfile (package:dispatch_data/src/profiles/profile_repositories/profile_dao.dart:146:27)
                 #6      DefaultProfileRepository.updateProfile (package:dispatch_data/src/profiles/profile_repositories/profile_repository.dart:29:34)
                 #7      DefaultProfileService.updateProfile (package:dispatch_data/src/profiles/profile_services/profile_service.dart:110:23)
                 #8      ProfileController.updateProfile (package:dispatch_controller/src/controllers/profile_controller.dart:64:21)
                 <asynchronous suspension>
                 #9      _LookAndFeelSettingsPageState.setToWallpaperMode (package:dispatch/view/routes/settings/pages/general/home_and_wallpaper/look_and_feel/look_and_feel.dart:153:5)
                 <asynchronous suspension>

[simolus3]

Well, you have a non-nullable name column in the database. How would an insert work if you supply Value.absent()? You can make the column nullable() in the definition, but apart from that a name would be required.

[spauldhaliwal]

I believe I misunderstood the documentation, but what I was trying to achieve was essentially: If name == null, don't update that column and leave the old value. Is such a thing possible with drift?

[simolus3]

That would be possible with updates, but you're using insertOnConflictUpdate. That operation could do an insert, and so we need a value for name: Something like update(profiles).replace(profile) should work.

Or is the idea that you want to insert a new row, but if one with the same profile id already exists, you update all columns except for the name?