/// <summary>
/// 获取列名
/// </summary>
/// <typeparam name="TEntity">实体类型</typeparam>
/// <param name="columns">列名表达式</param>
/// <param name="propertyAsAlias">是否将属性名映射为列别名</param>
public string GetColumns <TEntity>(Expression <Func <TEntity, object[]> > columns, bool propertyAsAlias) => Lambdas.GetLastNames(columns).Select(column => $"t_{column}").Join();