ecto migration

gistfile1.ex

iex(2)> defmodule MyApp.MigrationExample do
...(2)>   use Ecto.Migration
...(2)>
...(2)>   def up do
...(2)>     "CREATE TABLE user(id serial PRIMARY_KEY, username text)"
...(2)>   end
...(2)>
...(2)>   def down do
...(2)>     "DROP TABLE user"
...(2)>   end
...(2)> end
{:module, MyApp.MigrationExample,
 <<70, 79, 82, 49, 0, 0, 8, 200, 66, 69, 65, 77, 65, 116, 111, 109, 0, 0, 0, 144, 0, 0, 0, 14, 29, 69, 108, 105, 120, 105, 114, 46, 77, 121, 65, 112, 112, 46, 77, 105, 103, 114, 97, 116, 105, 111, 110, 69, 120, 97, ...>>,
 {:down, 0}}
iex(3)> Ecto.Migrator.up(Repo, 20080906120000, MyApp.MigrationExample)
** (Postgrex.Error) ERROR (42601): syntax error at or near "user"
            lib/ecto/adapters/postgres/worker.ex:15: Ecto.Adapters.Postgres.Worker.query!/2
            lib/ecto/adapters/postgres.ex:238: Ecto.Adapters.Postgres.use_worker/2
            lib/ecto/adapters/postgres.ex:359: anonymous fn/3 in Ecto.Adapters.Postgres.run_commands/3
    (elixir) lib/enum.ex:517: Enum."-each/2-lists^foreach/1-0-"/2
    (elixir) lib/enum.ex:517: Enum.each/2
            lib/ecto/adapters/postgres.ex:207: Ecto.Adapters.Postgres.transaction/2
            lib/ecto/adapters/postgres.ex:357: Ecto.Adapters.Postgres.run_commands/3
iex(3)> Repo.migrate_up(Repo, 20080906120000, "CREATE TABLE users(id serial, name text)")
** (UndefinedFunctionError) undefined function: Repo.migrate_up/3
    (ecto_test) Repo.migrate_up(Repo, 20080906120000, "CREATE TABLE users(id serial, name text)")
iex(3)> MyApp.MigrationExample.
__migration__/0    down/0             up/0
iex(3)> MyApp.MigrationExample.up
"CREATE TABLE user(id serial PRIMARY_KEY, username text)"