Add new QueryHelper module into example test support folder

This module contains functions related with models queries for test purposes

example/test/support/query_helper.exs

@@ -0,0 +1,24 @@
+defmodule QueryHelper do
+  import Ecto.Query
+
+  # Company related query functions
+  def company_count(), do: (from company in Company, select: count(company.id))
+  def company_count(:multitenant), do: company_count() |> MultiTenantHelper.add_prefix_to_query()
+
+  def first_company(), do: (first(Company, :id) |> preload(:people))
+  def first_company(:multitenant), do: first_company() |> MultiTenantHelper.add_prefix_to_query()
+
+  def filter_company(opts), do: (from c in Company, where: c.name == ^opts[:name], limit: ^opts[:limit])
+  def filter_company(opts, :multitenant), do: filter_company(opts) |> MultiTenantHelper.add_prefix_to_query()
+
+  # Person related query functions
+  def person_count(), do: (from person in Person, select: count(person.id))
+  def person_count(:multitenant), do: person_count() |> MultiTenantHelper.add_prefix_to_query()
+
+  def first_person(), do: (first(Person, :id) |> preload(:company))
+  def first_person(:multitenant), do: first_person() |> MultiTenantHelper.add_prefix_to_query()
+
+  # Version related query functions
+  def version_count(), do: (from version in PaperTrail.Version, select: count(version.id))
+  def version_count(:multitenant), do: version_count() |> MultiTenantHelper.add_prefix_to_query()
+end