Example of proper referencing of FSharp.Data.Npqsql to be able use it from FSI (in project running on dotnetcore)

Database.fs

module Database

open FSharp.Data
open FSharp.Data.Npgsql

[<Literal>]
let example = "Host=localhost;Username=postgres;Database=example;Port=5432"

type Example = NpgsqlConnection<example>

let printEmailsAndPhones() =
    use cmd = Example.CreateCommand<"SELECT email, phone FROM users"> (example)
    for x in cmd.Execute() do
        printfn "email : %s, phone: %s" x.email x.phone.Value

Scratch.fsx

#I "/Users/yourusername/.nuget/packages/fsharp.data.npgsql/0.1.44-beta/typeproviders/fsharp41/netcoreapp2.0"
#r "FSharp.Core.dll"
#r "Microsoft.Extensions.FileProviders.Physical.dll"
#r "FSharp.Data.Npgsql.DesignTime.dll"
#r "Npgsql.dll"

#I "/Users/yourusername/.nuget/packages/fsharp.data.npgsql/0.1.44-beta/lib/netstandard2.0/"
#r "FSharp.Data.Npgsql.dll"

#load "Database.fs"
open Database
printEmailsAndPhones()