/// <summary>
/// 调用 SQL IN 函数
/// </summary>
/// <typeparam name="T">字段栏数据库类型</typeparam>
/// <typeparam name="Table">数据库表数据库类型</typeparam>
/// <param name="field">字段栏</param>
/// <param name="gb">查询构建器</param>
/// <returns>表示此SQL 函数的返回值类型。只能在 SQL 构建器中调用，当直接调用此 SQL 函数时将引发 <see cref="NotSupportedException"/> 异常。</returns>
/// <exception cref="NotSupportedException">只能在 SQL 构建器中调用，当直接调用此 SQL 函数时将引发此异常。</exception>
public static bool In_ <T, Table>(this T field, GetBuilder <Table> gb)
where T : struct
where Table : class, new()
{
throw new NotSupportedException("不能直接调用此方法，只能在 SQL 构建器中调用。");
}
/// <summary>
/// 从指定查询构建器里查询数据，如“FROM (SQL 语句)”
/// </summary>
/// <param name="from">查询构建器</param>
/// <returns>查询构建器</returns>
public GetBuilder <T> From(GetBuilder <T> from)
{
__from = from;
return(this);
}
/// <summary>
/// 调用 SQL NOT IN 操作符(Where)
/// </summary>
/// <typeparam name="T"></typeparam>
/// <typeparam name="Table"></typeparam>
/// <param name="field">字段栏</param>
/// <param name="gb"></param>
/// <returns>表示此SQL 函数的返回值类型。只能在 SQL 构建器中调用，当直接调用此 SQL 函数时将引发 <see cref="NotSupportedException"/> 异常。</returns>
/// <exception cref="NotSupportedException">只能在 SQL 构建器中调用，当直接调用此 SQL 函数时将引发此异常。</exception>
public static bool ExNotIn <T, Table>(this T field, GetBuilder <Table> gb)
where Table : IModel
{
throw new NotSupportedException("不能直接调用此方法，只能在 SQL 构建器中调用。");
}