/// <summary>
/// 构建一个用于嵌套查询的子查询 [与Select(...)方法的构建方式一致]。
/// </summary>
/// <param name="fields">要查询的字段列表。</param>
/// <returns></returns>
public SelectBlock Nested(params IDescription[] fields)
{
SelectBlock sblock = new SelectBlock();
foreach (IDescription des in fields)
{
sblock.AddElement(des);
}
return(sblock);
}
/// <summary>
/// 开始构建 SELECT 命令。
/// </summary>
/// <param name="fields">要查询的字段列表（可以为字段信息入表达式对象）。</param>
/// <returns></returns>
public SelectBlock Select(params IDescription[] fields)
{
if (IsParsed)
{
ResetCommandBuilder();
}
SelectBlock sb = new SelectBlock();
foreach (IDescription des in fields)
{
sb.AddElement(des);
}
CommandDescription = sb;
return(sb);
}