Database Migration

Database Migration allows you to apply changes to a database schema in a controlled and repeatable way.

Instead of manually modifying database structures, migrations record each schema change as a sequence of operations that can be reviewed, versioned, and executed consistently.

Using migrations helps keep development, staging, and production databases synchronized.

Before you begin

Before creating a migration, ensure that you have:

Completed your database design
Validated the database schema
Connected to the target database (if deployment is required)

[!NOTE] Database Migrations modify the database structure. Always review migration scripts before applying them.

Why use migrations?

Database Migrations help you:

Track schema changes
Synchronize multiple environments
Maintain version history
Reduce deployment errors
Collaborate with team members

Migration workflow


Modify Database Model
          │
          ▼
Detect Schema Changes
          │
          ▼
Generate Migration
          │
          ▼
Review Migration
          │
          ▼
Apply Migration

Create a migration

To create a migration:

Open Database Engineering.
Select Database Migration.
Compare the current schema with the target schema.
Generate a migration.
Review the generated operations.
Save the migration.

Migration operations

A migration may contain operations such as:

Operation	Description
Create Table	Create a new table
Drop Table	Remove an existing table
Add Column	Add a new column
Remove Column	Delete a column
Rename Column	Rename a column
Modify Column	Change a column definition
Add Constraint	Create a new constraint
Remove Constraint	Delete an existing constraint
Create Index	Create a new index
Drop Index	Remove an existing index

Review before applying

Before applying a migration, review:

Added objects
Removed objects
Modified columns
Constraint changes
Relationship updates

Carefully reviewing migrations helps prevent unintended database changes.

Apply a migration

After reviewing the migration:

Select the target database.
Confirm the migration.
Apply the changes.
Verify the updated database schema.

Once completed, the database structure reflects the new schema.

Migration history

Each migration should be stored as part of your project’s history.

Maintaining migration history allows you to:

Understand previous database changes
Review schema evolution
Collaborate with team members
Track deployment history

Validation

Before applying a migration, Qubase validates:

Invalid operations
Missing dependencies
Broken relationships
Constraint conflicts
Unsupported modifications

Validation helps reduce migration failures.

Best practices

Review every migration before applying it.
Test migrations in a development environment first.
Keep migration history under version control.
Apply migrations in the correct order.
Back up important databases before major schema updates.

[!WARNING] Applying migrations directly to production databases without testing may result in unexpected downtime or data loss.