【发布时间】：2013-05-30 12:26:29
【问题描述】：
我目前正在开发一个 c#、MVC3、NHibernate（在 MSSQL 2008 上）应用程序。 我将提供一个简化的示例，因为我认为这是理解这一点的最佳方式。
型号：
class Stock
{
public Company Company {get;set;}
public Product Product {get;set;}
public int quantity {get;set;}
}
class TransactionHeader
{
public Company FromCompany {get;set;}
public Company ToCompany {get;set;}
public IList<TransactionRow> Rows {get;set;}
}
class TransactionRows
{
public Product Product {get;set;}
public TransactionHeader Header {get;set;}
public int Quantity {get;set;}
}
class Company
{
public Country Country {get;set;}
public State State {get;set;}
public string Name {get;set;}
}
我的最终目标是生成一个包含以下内容的列表：
产品名称、公司名称、国家名称、州名称、当前库存数量、进货数量、出库数量
我可以用这个查询对当前股票执行此操作：
var stockQuery = session.QueryOver<Stock>(() => s)
.JoinAlias<Company>(() => s.company, () => c, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.JoinAlias<State>(() => c.State, () => state, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.JoinAlias<Country>(() => c.Country, () => country, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.JoinAlias<Product>(() => s.product, () => p, NHibernate.SqlCommand.JoinType.InnerJoin, null);
if (productId.HasValue) { stockQuery = stockQuery.Where(() => p.Id == productId); }
var stock = stockQuery.SelectList(list => list
.Select(() => s.currentStock).WithAlias(() => rowVM.CurrentStock)
.Select(() => c.Description).WithAlias(() => rowVM.CompanyName)
.Select(() => state.Description).WithAlias(() => rowVM.StateName)
.Select(() => country.Description).WithAlias(() => rowVM.CountryName)
.Select(() => p.Description).WithAlias(() => rowVM.ProductName))
.TransformUsing(Transformers.AliasToBean<StockLevelRowVM>())
.List<StockLevelRowVM>();
我坚持的是如何根据 TransactionHeader / TransactionRow 数据添加进出库存。 这是我尝试查询来获取传入的股票编号：
var incommingQuery = session.QueryOver<TransactionRow>(() => itr)
.JoinAlias<TransactionHeader>(() => itr.TransactionHeader, () => ith, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.JoinAlias<Company>(() => ith.ToCompany, () => c, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.JoinAlias<Product>(() => itr.Product, () => p, NHibernate.SqlCommand.JoinType.InnerJoin, null)
.SelectList(list => list
.SelectGroup(() => new { ith.ToCompany, itr.Product })
.Select(() => itr.Quantity).WithAlias(() => detail.Quantity)
.Select(() => p.Id).WithAlias(() => detail.ProductId)
.Select(() => c.Id).WithAlias(() => detail.CompanyId))
按多个属性分组似乎不起作用：
Could not determine member from new <>f__AnonymousType3`2(ToCompany = value(<Stuff>).ith.ToCompany, Product = value(<Stuff>).itr.Product)
所以这引出了两个问题：
- 我的整个事情都错了吗？存储过程会是更好的解决方案吗？
- 如果这种方法很好，那么如何按多个字段进行分组？
编辑：我想要生成的那种 SQL 示例：
SELECT c.Description CompanyName,
p.Description ProductName,
cc.Description CountryName,
cs.Description StateName,
tmp.CurrentStock,
tmp.OutgoingStock,
tmp.IncommingStock
FROM
(
SELECT results.CompanyId,
results.ProductId,
SUM(results.CurrentStock) CurrentStock,
SUM(results.IncommingStock) IncommingStock,
SUM(results.OutgoingStock) OutgoingStock
FROM (
SELECT
c.Id CompanyId,
p.Id ProductId,
s.CurrentStock,
0 IncommingStock,
0 OutgoingStock
FROM Stock s
INNER JOIN Company c ON c.Id = s.Company
INNER JOIN [State] cs ON cs.Id = c.[State]
INNER JOIN Country cc ON cc.Id = cs.Country
INNER JOIN Product p ON p.Id = s.Product
WHERE (@CompanyId IS NULL OR c.Id = @CompanyId) AND
(@CountryId IS NULL OR cc.Id = @CountryId) AND
(@StateId IS NULL OR cs.Id = @StateId) AND
(@ProductId IS NULL OR p.Id = @ProductId)
UNION
SELECT
c.Id CompanyId,
p.Id ProductId,
0 CurrentStock,
0 IncommingStock,
tr.Quantity OutgoingStock
FROM TransactionRow tr
INNER JOIN TransactionHeader th ON th.Id = tr.TransactionHeader
INNER JOIN Company c ON c.Id = th.FromCompany
INNER JOIN [State] cs ON cs.Id = c.[State]
INNER JOIN Country cc ON cc.Id = cs.Country
INNER JOIN Product p ON p.Id = tr.Product
WHERE (@CompanyId IS NULL OR c.Id = @CompanyId) AND
(@CountryId IS NULL OR cc.Id = @CountryId) AND
(@StateId IS NULL OR cs.Id = @StateId) AND
(@ProductId IS NULL OR p.Id = @ProductId)
UNION
SELECT
c.Id CompanyId,
p.Id ProductId,
0 CurrentStock,
tr.Quantity IncommingStock,
0 OutgoingStock
FROM TransactionRow tr
INNER JOIN TransactionHeader th ON th.Id = tr.TransactionHeader
INNER JOIN Company c ON c.Id = th.ToCompany
INNER JOIN [State] cs ON cs.Id = c.[State]
INNER JOIN Country cc ON cc.Id = cs.Country
INNER JOIN Product p ON p.Id = tr.Product
WHERE (@CompanyId IS NULL OR c.Id = @CompanyId) AND
(@CountryId IS NULL OR cc.Id = @CountryId) AND
(@StateId IS NULL OR cs.Id = @StateId) AND
(@ProductId IS NULL OR p.Id = @ProductId)
) results
GROUP BY results.CompanyId, results.ProductId
) tmp
INNER JOIN Company c ON c.Id = tmp.CompanyId
INNER JOIN [State] cs ON cs.Id = c.[State]
INNER JOIN Country cc ON cc.Id = cs.Country
INNER JOIN Product p ON p.Id = tmp.CompanyId
编辑 2：所需 SQL 的第二个版本
SELECT
c.Id CompanyId,
c.Description CompanyName,
p.Id ProductId,
p.Description ProductName,
cs.Description StateName,
cc.Description CountryName,
SUM(s.CurrentStock) CurrentStock,
SUM(ttr.Quantity) IncommingStock,
SUM(ftr.Quantity) OutgoingStock
FROM Stock s
INNER JOIN Company c ON c.Id = s.Company
INNER JOIN [State] cs ON cs.Id = c.[State]
INNER JOIN Country cc ON cc.Id = cs.Country
INNER JOIN Product p ON p.Id = s.Product
LEFT JOIN TransactionHeader fth ON fth.FromCompany = c.Id
LEFT JOIN TransactionRow ftr ON ftr.TransactionHeader = fth.ID
AND ftr.Product = p.Id
LEFT JOIN TransactionHeader tth ON tth.ToCompany = c.Id
LEFT JOIN TransactionRow ttr ON ttr.TransactionHeader = tth.ID
AND ttr.Product = p.Id
WHERE (@CompanyId IS NULL OR c.Id = @CompanyId) AND
(@CountryId IS NULL OR cc.Id = @CountryId) AND
(@StateId IS NULL OR cs.Id = @StateId) AND
(@ProductId IS NULL OR p.Id = @ProductId)
GROUP BY p.Id, c.Id, c.Description, p.Description,
cs.Description, cc.Description
【问题讨论】：
-
您能展示一下您希望生成的 SQL 吗？那样想出 QueryOver 会更容易。
-
@AndrewWhitaker 我没有任何 SQL 可继续，但将一些 SQL 拼凑在一起并将其添加到问题中。它可能不是 100% 正确，但希望能传达我想要实现的目标。
-
嗯，您将无法使用 QueryOver 执行
UNION或从表表达式 (FROM (SELECT ... )) 中进行选择。 -
啊，好的。我想我会走存储过程路线。感谢收看。
-
我添加了另一个可能更可行的预期 SQL 变体。它也可能会慢一些……目前还不确定。
标签： c# nhibernate