haskell-hdbc-tool #1: とりあえず簡単なクエリを動かすことができた。 (Github 2013-05-11時点のhaskell-hdbc-toolを使用)

PostgreSQL.hs

{-# LANGUAGE ScopedTypeVariables #-}

module Database.Test.PostgreSQL
  (
    connect
  , defineTable
  ) where

import Language.Haskell.TH                (Dec, Q) 
import Language.Haskell.TH.Name.CamelCase (ConName)
import Database.HDBC.PostgreSQL           (Connection, connectPostgreSQL)
import Database.HDBC.Schema.PostgreSQL    (driverPostgreSQL)
import Database.HDBC.TH                   (defineTableFromDB)

{-# ANN module "HLint: ignore Eta reduce" #-}

connect :: IO Connection
connect = connectPostgreSQL "host=localhost port=50254 dbname=mdm user=postgres password=****"

defineTable :: String -> String -> [ConName] -> Q [Dec]
defineTable scm tbl derives =
    defineTableFromDB
        connect
        driverPostgreSQL
        scm tbl derives

Query.hs

{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE ScopedTypeVariables #-}

module Database.Test.Query where

import Database.HDBC.Record.Query         (runQuery')
import Database.HDBC.Session              (withConnectionIO)
import Database.Relational.Query          (Query)
import Database.Relational.Query.Join     (from, relation)
import Database.Relational.Query.Type     (fromRelation)
import Database.Test.PostgreSQL           (connect)

import qualified Database.Test.Schema     as SC

{-# ANN module "HLint: ignore Eta reduce" #-}

test1 :: IO [SC.TTenant]
test1 = withConnectionIO connect $ \conn ->
    runQuery' conn () queryTTenant

queryTTenant :: Query () SC.TTenant
queryTTenant = fromRelation $ relation $ from SC.tableOfTTenant

Schema.hs

{-# LANGUAGE EmptyDataDecls #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}

module Database.Test.Schema where         

import Database.Test.PostgreSQL                    (defineTable)
import Language.Haskell.TH.Name.CamelCase          (toConName)
import Prelude                             hiding  (id)

$(defineTable "public" "t_tenant" [toConName "Show"])