I developed an app with postgres DB but want to change the DB to
sqlite3. I changed the database adapter in the database.yml file. When I
run the migration most of it was successful but add_column was throwing
“Cannot add a NOT NULL column with default value NULL: ALTER TABLE
“rates” ADD “customer_id” integer NOT NULL”.
I made the modification and added the columns to the original migration
of the table and ran the migration again. Everything seems to work fine.
Why is add_column causing rake to abort during migration? Is there any
patch for the problem.