If you do it in a migration then you could probably do it like this: # Make sure no null value exist MyModel.where(date_column: nil).update_all(date_column: Time.now) # Change the column to not allow null change_column :my_models, :date_column, :datetime, null: false
You need to figure out the number of the migration just before the one you want to roll back. Your app should have a migrations directory, with files in it named like 0000_initial.py 0001_added_some_fields.py 0002_added_some_more_fields.py 0003_deleted_some_stuff.py Normally, when you run ./manage.py migrate your_app, South runs all new migrations, in order. (It looks at the database … Read more
You have 2 options: You can take the Down from the bad migration and put it in a new migration (you will also need to make the subsequent changes to the model). This is effectively rolling up to a better version. I use this option on things that have gone to multiple environments. The other … Read more
First in your terminal: rails g migration change_date_format_in_my_table Then in your migration file: For Rails >= 3.2: class ChangeDateFormatInMyTable < ActiveRecord::Migration def up change_column :my_table, :my_column, :datetime end def down change_column :my_table, :my_column, :date end end
Add it in two steps, and it’s good to make it unsigned too: public function up() { Schema::create(‘priorities’, function($table) { $table->increments(‘id’, true); $table->integer(‘user_id’)->unsigned(); $table->string(‘priority_name’); $table->smallInteger(‘rank’); $table->text(‘class’); $table->timestamps(‘timecreated’); }); Schema::table(‘priorities’, function($table) { $table->foreign(‘user_id’)->references(‘id’)->on(‘users’); }); }
Everyone seems to starts off with a few greps and perl expressions and you sorta kinda get something that works for your particular dataset but you have no idea if it’s imported the data correctly or not. I’m seriously surprised nobody’s built a solid library that can convert between the two. Here a list of … Read more
Here is a link to the official docs which include the main points in this answer: android.database.sqlite package-level javadoc Kotlin code to get framework SQLite version (tip: just stick a breakpoint in your Activity onCreate() and use this code in Evaluate Expression…): val version = android.database.sqlite.SQLiteDatabase.create(null).use { android.database.DatabaseUtils.stringForQuery(it, “SELECT sqlite_version()”, null) } “Framework (API ${android.os.Build.VERSION.SDK_INT}) … Read more
Assuming fairly recent version of Rails you can always run: rake db:migrate:up VERSION=20090408054532 Where version is the timestamp in the filename of the migration. Edit: At some point over the last 8 years (I’m not sure what version) Rails added checks that prevent this from running if it has already been run. This is indicated … Read more
Here’s how you should do it: change_column :users, :admin, :boolean, :default => false But some databases, like PostgreSQL, will not update the field for rows previously created, so make sure you update the field manaully on the migration too.
The best solution would be to fix the javadoc errors. If for some reason that is not possible (ie: auto generated source code) then you can disable this check. DocLint is a new feature in Java 8, which is summarized as: Provide a means to detect errors in Javadoc comments early in the development cycle … Read more