```ruby
class CreateCollaborationRuns < ActiveRecord::Migration
  def up
    create_table :collaboration_runs do |t|
      t.integer :user_id
      t.string :collaborators_data_url
      t.timestamps
    end
    add_column :runs, :collaboration_run_id, :integer

    add_index :collaboration_runs, [:collaborators_data_url], :name => 'collaboration_runs_endpoint_idx'
    add_index :runs, [:collaboration_run_id], :name => 'runs_collaboration_idx'
    # Rename index, as its previous name is too long and causes errors during this migration rollback.
    remove_index :runs, [:user_id, :remote_id, :remote_endpoint]
    add_index :runs, [:user_id, :remote_id, :remote_endpoint], :name => 'runs_user_remote_endpt_idx'
  end

  def down
    drop_table :collaboration_runs
    remove_column :runs, :collaboration_run_id

    # Use default index name again. Problems were in the line above, some temp index created during column
    # removal had name longer than 64 chars.
    remove_index :runs, :name => 'runs_user_remote_endpt_idx'
    add_index :runs, [:user_id, :remote_id, :remote_endpoint]
  end
end
```

Fix one of the migrations where column name was accidentally changed
user
```ruby
class CreateCollaborationRuns < ActiveRecord::Migration
  def up
    create_table :collaboration_runs do |t|
      t.integer :user_id
      t.string :collaboration_endpoint_url
      t.timestamps
    end
    add_column :runs, :collaboration_run_id, :integer

    add_index :collaboration_runs, [:collaboration_endpoint_url], :name => 'collaboration_runs_endpoint_idx'
    add_index :runs, [:collaboration_run_id], :name => 'runs_collaboration_idx'
    # Rename index, as its previous name is too long and causes errors during this migration rollback.
    remove_index :runs, [:user_id, :remote_id, :remote_endpoint]
    add_index :runs, [:user_id, :remote_id, :remote_endpoint], :name => 'runs_user_remote_endpt_idx'
  end

  def down
    drop_table :collaboration_runs
    remove_column :runs, :collaboration_run_id

    # Use default index name again. Problems were in the line above, some temp index created during column
    # removal had name longer than 64 chars.
    remove_index :runs, :name => 'runs_user_remote_endpt_idx'
    add_index :runs, [:user_id, :remote_id, :remote_endpoint]
  end
end
```
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