sqlite-simple-interpolate

Write natural SQL statements in Haskell using QuasiQuoters!

{-# LANGUAGE QuasiQuotes #-}

module Main where

import Control.Exception (bracket)
import Data.Char (toLower)
import Data.Function ((&))
import qualified Database.SQLite.Simple as SQL
import Database.SQLite.Simple.QQ.Interpolated

table :: String
table = "people"

main :: IO ()
main = bracket (SQL.open ":memory:") SQL.close $ \conn -> do
  conn & [iexecute|CREATE TABLE !{table} (name TEXT, age INTEGER)|]

  conn & [iexecute|INSERT INTO !{table} VALUES ("clive", 40)|]
  -- you can always use 'isql' directly but you'll have to use uncurry:
  (uncurry $ SQL.execute conn) [isql|INSERT INTO !{table} VALUES ("clara", 32)|]

  ageSum <- conn & [ifold|SELECT age FROM !{table}|] 0 (\acc (SQL.Only x) -> pure (acc + x))
  print (ageSum :: Int)

  let limit = 1 :: Int
  ages <- conn & [iquery|SELECT age FROM !{table} WHERE name = ${map toLower "CLIVE"} LIMIT ${limit}|]
  print (ages :: [SQL.Only Int])

Acknowledgements

This library is a fork of postgresql-simple-interpolate, adapted for use with sqlite-simple.

The original itself is basically just a copy of the here package by Taylor M. Hedberg with slight modifications!