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Modify Objects in a Realm File

On this page

  • Overview
  • Import from a CSV
  • Browse to the Import from CSV option
  • Select a CSV to import
  • Choose the destination class for your objects
  • Create an Object
  • Consider Object Relationships
  • Create the Object
  • Modify an Object
  • Change a Field Value
  • Change an Object's Relationships
  • Delete an Object
  • Save the Data
  • Use the JSON File
  • Use the Realm File

Realm Studio gives you the ability to view and modify objects in your realm file. You can:

  • Import data from a CSV

  • Create new objects

  • Modify and delete existing objects

You can then save the data as JSON or a realm file, and import it into your client app or production database.


If you want to use a new class when importing data, you must create the class before starting the import.


In Realm Studio, go to: File > Import data from > CSV


Browse to the location of your CSV file, and select it.

Press the Open button.


You'll see a drop-down selector containing the available classes in your realm file. Select the class where the imported data should become objects.

Press the Import data button.

Now you'll see newly-created objects created from the data you imported. Each object's properties map to the properties of the class you selected during import.

When you create a new object, think about the relationships between the objects. For example, a to-do app, might have categories and tasks. The categories have a to-many relationship to the tasks; one category may have many tasks. The tasks have an inverse relationship to the category.

In Realm, a to-many relationship is represented as a list property linking the two objects. In the example of a to-do app, the Category class has a list property whose value is all of the related Task objects.

In the Realm Studio UI, you would select the Category class. Click into the [list-of-task] property for the category where you want to add the task - for example, "Work".

Realm Studio screenshot showing the Category class selected and the "list of task" for category view.

You'll see all the task objects that have an inverse relationship with the Work category. When you create the new task object from within the Work list, Realm Studio sets the inverse relationship with the Work parent category.

Realm Studio screenshot showing the task objects belonging to the "Work" category, and the "Create task" button.

From here, you might create a new task object to "Review PR 1013." The new task will be linked to the "Work" category through an inverse relationship.

Realm Studio screenshot showing a user entering properties for a new task object, and the "Create" button.

If you select the Task class directly, you could create a new task object. But that task object would not have an inverse relationship with any parent category. You would then have to manually add the orphaned task object to the category where it belongs.


The left sidebar of Realm Studio displays the classes that comprise the schema. Select the class for the type of object you want to create.


Once you've decided where to create your new object, you can do this in two ways:

  • Click the Create {Class name} button in the upper right corner of the app

  • Right click (or control click) anywhere in the main window to bring up the contextual menu, and select Create new {Class name}

Either option will open a dialog where you can set the properties for the object. When you've specified the required properties, press the Create button.

If you create an orphaned object that is not associated with a parent object via a linking property, you'll need to add it manually to the linked object. See: Modify an Object.

There are a few ways you can modify a realm object in Realm Studio:

  • Change a field value

  • Change an object relationship

You can manually change an object's field values:

  • Click into the field of an object

  • Enter a different value

Realm Studio provides simple type validation, such as providing a list of acceptable boolean options: Use "true", "false", "0", or "1", or automatically converting a date into a valid datetime. However, this validation may lead to unexpected behavior. For example, typing "123abc" into an int field simply discards the non-numeric characters without providing user feedback or errors. Therefore, it is up to you to ensure the data you enter into a field value is of the correct type.

You can change an object's relationship with other objects using Realm Studio.

To add a new object relationship:

  • Click into the property that defines the relationship

  • Right-click (or control-click) anywhere in the main pane, and select Add existing {linked class name}

  • Select the object you want to link, and press the Select button


Adding an object relationship does not remove an existing object relationship. If you want to change an object relationship; for example, move a task from one category to another; you must also remove the relationship that linked the task to the old category.

To remove an object relationship:

  • Click into the property that defines the relationship.

  • Right-click (or control-click) the object whose relationship you want to remove, and select Remove selected row from the list or Delete selected object depending on the type of relationship.

  • You'll see a dialog asking you to confirm the action. Press the button to confirm you want to remove or delete the object.

To delete an object from a realm:

  • Right-click (or control-click) the object you want to delete, and select Delete selected object.

  • You'll see a dialog asking you to confirm the action. Press the Delete selected object button to confirm.


If you don't see the Delete selected object option, you may be viewing it in a linking relationship list view. Go directly to the class where the object is stored.

If you're in the class where the object is stored, and still don't see the Delete selected objects option, it may be because you have another object selected. Click to select the object you want to delete, and then right-click (or control-click) to get the delete option.

Because realm objects are live objects, you can make changes to a realm file and see them reflected in a client app in realtime. Realm Studio gives you a few save options if you want to do other things with the data. To save the file, follow these steps:

  1. Go to File > Save data and select JSON or Local Realm.

  2. Select the filename and destination where you want to save the file.

  3. Press the Save button.

If you have saved the data as JSON, you can import it back into your app. Use your preferred method to import the JSON into your app.


"Flatted" files

When exporting to a JSON file, Realm Studio uses the Flatted package. If you want to open the file in another application, you will need to use Flatted.parse().

If you save the data as a realm file, and you haven't modified the schema, you can use that realm file as a direct replacement for the existing realm file in your client app. Simply replace the existing realm file on your filesystem with the new one.

Alternately, you could save a copy of the realm, open the copy, and make schema changes on the copy. This would preserve your intact original realm file, but still enable you to iterate on schema. You would then be able to continue to use your existing realm file in your client app without performing a migration. You could test migrations for your new schema with the second realm file at your leisure.

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