text: 
  export async function up (knex) {
    await knex.schema.createTable('tarefas', function (table) {
      table.increments();
      table.text('descricao').notNullable();
      table.integer('id_categoria').notNullable().references('categorias.id');
      table.integer('id_usuario').notNullable().references('usuarios.id');
      table.timestamp('data_conclusao');
    });
  }
  
  export async function down () {
    throw new Error('não suportado');
  }
  