Truncating the Migration List itsself is easy. You only have to create a snapshot of the current database state (after correctly reseeding first).

php bin/cake.php bake migration_snapshot InitDb

Then you should check if it did it correctly. You can delete all other migrations and run the new migration. If the schema dump is the same it worked.

Be sure to check data update queries and redo them in the new unified migration if possible/necessary.

Source

Major changes include the swap from AbstractMigration to BaseMigration and the same with Seeds.

Be sure to check your seeds and migrations for any outputs. The new BaseMigration or BaseSeed use $this→getIo→out() instead of $this→getOutput→writeln().

Commands have also changed entirely from

php bin/cake.php migrations seed

to

php bin/cake.php seeds run