anchor.diff:      conn :> IDbConnection
   
   let connMgr = Sql.withNewConnection openConn
  +let inTransaction a = Sql.transactional connMgr a
  +let execScalar sql = Sql.execScalar connMgr sql
  +let execReader sql = Sql.execReader connMgr sql
  +let execReaderf sql = Sql.execReaderF connMgr sql
  +let execNonQueryf sql = Sql.execNonQueryF connMgr sql
   let exec a = Sql.execNonQuery connMgr a [] |> ignore
   exec "drop table if exists user"
   exec "create table user (id int primary key not null, name varchar not null, address varchar null)"
  
positive.code:         | Some x -> x
      printfn "Id: %d; Name: %s; Address: %s" id name address
  
  Sql.execReader connMgr "select * from user" []
  |> Seq.ofDataReader
  |> Seq.iter printUser
  
negative.code:                 else Some (sprintf "fake st %d" i)
          insertUser i name address |> ignore
  
  let insertNUsers2 n = insertNUsers n |> inTransaction
  
  insertNUsers2 50 ()
  
  let countUsers(): int64 =
      execScalar "select count(*) from user" []
  
  printfn "%d users" (countUsers())
  
  