Schema upgrades for UltraLite remote databases

You can change the schema of a remote UltraLite database by having your existing application execute DDL.

  • If you deploy a new application with a new database, you need to repopulate the UltraLite database by synchronizing with the MobiLink server.

  • If you deploy a new application that contains DDL to upgrade the database, your data is preserved.

  • If your existing application has a generic way to receive DDL statements, it can apply DDL to your database and your data is preserved.

It is usually impractical to have all users upgrade to the new version of the application at the same time. Therefore, you need to be able to have both versions co-existing in the field and synchronizing with a single consolidated database. You can create two or more versions of the synchronization scripts that are stored in the consolidated database and control the actions of the MobiLink server. Each version of your application can then select the appropriate set of synchronization scripts by specifying the correct version name when it initiates synchronization.

For information about UltraLite DDL, see UltraLite SQL statements.

 See also