[英]How to join two tables queries and select matching the records in Nhibernet linq?
I am trying to develop one single query which gives me records from both the table in one result using linq-Nhibernet query.我正在尝试开发一个单一的查询,它使用 linq-Nhibernet 查询在一个结果中为我提供两个表中的记录。
I have two tables first one:account (accountId, accountDescription) and second one: accountdescriptionhistory (accountId, description).我有两个表第一个:account(accountId,accountDescription)和第二个:accountdescriptionhistory(accountId,description)。 AccountId is foreign-key reference to second table.
AccountId 是对第二个表的外键引用。 Now, i am fetching all the records from first table with below query.
现在,我正在使用以下查询从第一个表中获取所有记录。
What i want is, If record exist in AccountDescriptionHistory for accountId reference than it should return me the description from AccountDescriptionHistory not from account table.我想要的是,如果 AccountDescriptionHistory 中存在用于 accountId 参考的记录,那么它应该返回来自 AccountDescriptionHistory 的描述而不是来自帐户表。 i want to achieve this in single query.
我想在单个查询中实现这一点。
Note: I need this in linq NHibernate query.注意:我在 linq NHibernate 查询中需要这个。
Adding a class details添加 class 详细信息
Account class look like below:帐户 class 如下所示:
public class Account : EntityModelHasOwner<Account>, ISupportsIdLookup
{
/// <summary>
/// The account number
/// </summary>
public virtual string AccountNumber { get; set; }
/// <summary>
/// The account's description
/// </summary>
public virtual string Description { get; set; }
}
Account description class:账户说明 class:
public class AccountDescriptionHistory : EntityModel<AccountDescriptionHistory>
{
#region Public Properties
/// <summary>
/// The account description of an account that is valid for a specific date range
/// </summary>
public virtual string AccountDescription { get; set; }
/// <summary>
/// The account this AccountDescriptionHistory is associated with.
/// </summary>
public virtual Account Account { get; set; }
}
You can accomplish this via a query.您可以通过查询来完成此操作。
/* this.Session is a NHibernate.ISession */
string hql = "FROM Account acc" +
" inner join fetch acc.MyAccountDetails"
"where acc.IsDeleted= :myIsDeletedParameter";
IQuery q = this.Session.CreateQuery(hql);
q.SetBoolean("myIsDeletedParameter", false);
IList<Account> returnItems = q.List<Account>();
return returnItems;
OR with a Fluent style;或流利的风格;
////using NHibernate;
////using NHibernate.Linq;
IQueryable<Account> returnItemsQuery = (from myalias in this.Session.Query<Account>()
.FetchMany(x => x.MyAccountDetails )
.Where(acc => false == acc.IsDeleted)
select myalias);
IList<Account> returnItems = returnItemsQuery.ToList();
I am assuming your poco looks like this.我假设你的 poco 看起来像这样。
public class Account
{
/* scalars */
public virtual ICollection<AccountDetails> MyAccountDetails {get; set;}
}
See:看:
https://nhibernate.info/doc/howto/various/lazy-loading-eager-loading https://nhibernate.info/doc/howto/various/lazy-loading-eager-loading
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.