It seems that Umbraco Cloud databases have 4 additional tables.

Create copies of the following 4 tables based on the local database you cloned from the new Umbraco 10 Cloud Site.

umbracoCreatedPackageSchema

umbracoDeployDependency

umbracoDeploySignature

umbracoIdTockenCache

Thanks Marc, done that and its got me in :)

I stopped the site to carry on with the upgrade and now when i run it i just get the following error about a duplicate dictionary key

Cloned Umbraco Cloud environments will by default try to run package migrations. uSkinned Site Builder will run a package migration to create demo content and setup other settings. In this upgrade scenario you do not want the package migration to run again. You need to disable the default behaviour of Umbraco Cloud with the following settings:

{
  "$schema": "https://json.schemastore.org/appsettings.json",
  "Umbraco": {
    "CMS": {
      "PackageMigration": {
        "RunSchemaAndContentMigrations": false,
        "AllowComponentOverrideOfRunSchemaAndContentMigrations": false
      }
    }
  }
}

Thanks Marc,

This helps and allows us to get further until...

The complete process to replicate this is

1. Connect to live v8 database and export as .bacpac
2. Import locally into SSMS
3. run script to add missing cloud tables to database
4. Clone v10 dev environment locally
5. Update connection string to local v8 database
6. Change unattended upgrade and package migration settings (including latest override setting)
7. Build site (otherwise folder in next step does not exist)
8. Copy /usn/updates/3.x contents to root
9. Run site
10. Go to backend > usync and import settings and content
11. Stop project
12. Start project {error}

The v8 uSkinned project we're trying to upgrade is quite simple in structure so i'm surprised no one else has come across this so far. Would be great if someone else can try this to try and find a solution

To update: the above error is related to Umbraco Forms. Like someone else in the forum post below, I'd also decided not to migrate my v8 forms to the db as it would be easier to just rebuild them in the new v10 site.

https://our.umbraco.com/forum/using-umbraco-and-getting-started/109436-umbraco-forms-upgrade-v8-to-v10

Running this on the DB resolves it

DELETE FROM umbracoKeyValue
WHERE [key] = 'Umbraco.Core.Upgrader.State+UmbracoForms'

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