text: /*
   * Copyright (c) 2013-2015, Roland Bock
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   *  * Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   *  * Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
   * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "Sample.h"
  #include "MockDb.h"
  #include <sqlpp11/select.h>
  #include <sqlpp11/alias_provider.h>
  #include <iostream>
  
  namespace greek
  {
    SQLPP_ALIAS_PROVIDER(alpha)
    SQLPP_ALIAS_PROVIDER(beta)
  }
  
  int Union(int, char* [])
  {
    MockDb db;
    MockDb::_serializer_context_t printer = {};
  
    const auto t = test::TabBar{};
    const auto f = test::TabFoo{};
  
    db(select(t.alpha).from(t).unconditionally().union_distinct(select(f.epsilon.as(t.alpha)).from(f).unconditionally()));
    db(select(t.alpha).from(t).unconditionally().union_all(select(f.epsilon.as(t.alpha)).from(f).unconditionally()));
  
    // t.alpha can be null, a given value cannot
    db(select(t.alpha).from(t).unconditionally().union_all(select(sqlpp::value(1).as(t.alpha))));
    db(select(t.alpha).from(t).unconditionally().union_all(select(sqlpp::value(1).as(greek::alpha))));
  
    // t.beta can be null, f.delta cannot
    static_assert(sqlpp::can_be_null_t<decltype(t.beta)>::value, "");
    static_assert(!sqlpp::can_be_null_t<decltype(f.delta)>::value, "");
    db(select(t.beta).from(t).unconditionally().union_all(select(f.delta.as(greek::beta)).from(f).unconditionally()));
  
    auto u = select(t.alpha)
                 .from(t)
                 .unconditionally()
                 .union_all(select(f.epsilon.as(t.alpha)).from(f).unconditionally())
                 .as(sqlpp::alias::u);
  
    db(select(all_of(u)).from(u).unconditionally().union_all(select(t.delta.as(t.alpha)).from(t).unconditionally()));
    db(select(u.alpha).from(u).unconditionally().union_all(select(t.delta.as(t.alpha)).from(t).unconditionally()));
  
    db(select(t.alpha)
           .from(t)
           .unconditionally()
           .union_all(select(t.alpha).from(t).unconditionally())
           .union_all(select(t.alpha).from(t).unconditionally()));
  
    return 0;
  }
  