We use Vs2019 with an older version of Nhibernate 3.2.
We recently upgraded to VS2019. This code worked correctly in VS2010.
We are getting this error with Nibernate QueryOver, lambda expressions inside a where clause. I stripped it down to a minimal version. During runtime Block 1 fails and Block 2 does not. Why? I can't figure this out.
Could it be something related to .net framework 4.8, roselyn or an older version of Nhibernate?
I didn't post all the Business Objects here but if needed I can do so. I am also seeing this behavior across the application for different Business Objects.
could not resolve property: CS$<>8__locals2 of: BusinessObjectMain
Block 1
var EventQuery = session.QueryOver<BusinessObjectMain()
.JoinAlias(ce => ce.Bo1, () => Bo1)
.JoinAlias(ce => ce.Bo2, () => Bo2, JoinType.LeftOuterJoin)
.JoinAlias(() => Bo2.Bo3, () =>Bo3, JoinType.LeftOuterJoin)
;
for (int i = 0; i < 1; i++) {
object[] arr = new object[1];
arr[0] = 202;
EventQuery = EventQuery.Where(() => Bo3.TypeId.IsIn(arr));
}
var Results = EventQuery.Future<Data>();
var list = Results.ToList();---Error happens here. could not resolve property: CS$<>8__locals2 of: BusinessObjectMain
Why does the code below work? If I move the Where clause outside the for loop, it works correctly without any errors
Block 2
var EventQuery = session.QueryOver<BusinessObjectMain()
.JoinAlias(ce => ce.Bo1, () => Bo1)
.JoinAlias(ce => ce.Bo2, () => Bo2, JoinType.LeftOuterJoin)
.JoinAlias(() => Bo2.Bo3, () =>Bo3, JoinType.LeftOuterJoin)
;
object[] arr = new object[1];
arr[0] = 202;
EventQuery = EventQuery.Where(() => Bo3.TypeId.IsIn(arr));
for (int i = 0; i < 1; i++) {
}
var Results = EventQuery.Future<Data>();
var list = Results.ToList()
It's a bug in NHibernate related to Roslyn compiler that's used since Visual Studio 2015 (because Roslyn compiles lambda's differently). See https://nhibernate.jira.com/browse/NH-3795, https://github.com/nhibernate/nhibernate-core/pull/441
It's fixed in NHibernate versions 3.3.5, 3.4.1 and 4.0.4+
Related
I am new to elasticsearch so I will need some help. Unfortunately, I didnt found the answer in other topics here on SO.
I have some .net core application which I inherited and now there is a need to implement some changes.
I already have a method of getting data from elasticsearch, but after getting them, I am not sure how to change it and use it in application.
To be precise, I need to parse first and last name and to remove special characters, specific serbian latin letters like "šđžčć" etc... I already have a method for this parsing written but not sure how to call it...
So, my question is can I and how can I do this?
What I have now is the following:
var result = await _elasticClient.SearchAsync<CachedUserEntity>(
s =>
s.Index(_aliasName)
.Query(q => andQuery));
CachedUserEntity, among others, contains property about FirstName and LastName.
Inside results.Documents, I am getting the data about FirstName and LastName from elasticsearch, but I am not sure how to access it in order to update it via aformentioned NameParser ...
Sorry if the question is too easy, not to say stupid :)
I wont use updateByQuery here, for some reasons. I would scroll on documents (i use matchAll on my exemple, you obviously need to replace it with your query), or, if you dont know how to identify documents to update, only update usefull documents in UpdateManyWithIndex/UpdateManyPartial function.
For performance, we have to update severals documents at once, so we use bulk/updateMany function.
You can use both solution, the classic update, or the second (partial update) with an object containing the targeteds fields.
On server sides, both solutions will have the same cost / performance.
var searchResponse = Client.Search<CachedUserEntity>(s => s
.Query(q => q
MatchAll()
)
.Scroll("10s")
);
while (searchResponse.Documents.Any())
{
List<CachedUserEntity> NewSearchResponse = RemoveChar(searchResponse);
UpdateManyWithIndex<CachedUserEntity>(NewSearchResponse, _aliasName);
searchResponse = Client.Scroll<Project>("2h", searchResponse.ScrollId);
}
public void UpdateManyWithIndex<C>(List<C> obj, string index) where C : class {
var bulkResponse = Client.Bulk(b => b
.Index(index).Refresh(Elasticsearch.Net.Refresh.WaitFor) // explicitly provide index name
.UpdateMany<C>(obj, (bu, d) => bu.Doc(d)));
}
Or, using partial update object
Note: in this case Indix is already set on my client (add .index if needed)
var searchResponse = Client.Search<CachedUserEntity>(s => s
.Query(q => q
MatchAll()
)
.Scroll("2h")
);
while (searchResponse.Documents.Any())
{
List<object> listPocoPartialObj = GetPocoPartialObjList(searchResponse);
UpdateManyPartial(listPocoPartialObj);
searchResponse = Client.Scroll<Project>("2h", searchResponse.ScrollId);
}
private List<object> GetPocoPartialObjList(List<CachedUserEntity> cachedList) {
List<object> listPoco = new List<object>();
//note if you dont have cachedList.Id, take a look at result.source, comments if needed
foreach (var eltCached in cachedList) {
listPoco.Add( new object() { Id = cachedList.Id, FirstName = YOURFIELDWITHOUTSPECIALCHAR, LastName = YOURSECONDFIELDWITHOUTSPECIALCHAR});
}
return listPoco;
}
public bool UpdateManyPartial(List<object> partialObj)
{
var bulkResponse = Client.Bulk(b => b
.Refresh(Elasticsearch.Net.Refresh.WaitFor)
.UpdateMany(partialObj, (bu, d) => bu.Doc(d))
);
if (!bulkResponse.IsValid)
{
GetErrorMsgs(bulkResponse);
}
return (bulkResponse?.IsValid == true);
}
Suppose the following Query using a NH 3.4 and RepositoryPattern
var list = _repository
.QueryOver()
.Where(x => (x.Age > 20)) // notice the parantheses
.Future()
.ToList();
Whith these parantheses added the NH is failing to work, and causes a SO exception.
If replacing .Where(x => (x.Age > 20)) with .Where(x => x.Age > 20)
it works as expected.
Any clues on why it doesn't work with extra parantheses?
Note
This is a simplified scenario from the bigger picture. In production i'm passing that .Where(...) through a parameter Expression<Func<Person, bool>> where
I have a doubt the error is there:
Expression<Func<MyClass, bool>> mc1 = x => (x.ID > 20);
Expression<Func<MyClass, bool>> mc2 = x => x.ID > 20;
var body1 = mc1.Body.NodeType; // GreatThan
var body2 = mc2.Body.NodeType; // GreatThan
The brackets are removed by the compiler. There is nothing in the Expression tree "language" (class system) to explicitly represent a bracket.
I have the following query:
var list = repositoy.Query<MyClass>.Select(domain => new MyDto()
{
Id = domain.Id,
StringComma = string.Join(",", domain.MyList.Select(y => y.Name))
});
That works great:
list.ToList();
But if I try to get the Count I got an exception:
list.Count();
Exception
NHibernate.Hql.Ast.ANTLR.QuerySyntaxException
A recognition error occurred. [.Count[MyDto](.Select[MyClass,MyDto](NHibernate.Linq.NhQueryable`1[MyClass], Quote((domain, ) => (new MyDto()domain.Iddomain.Name.Join(p1, .Select[MyListClass,System.String](domain.MyList, (y, ) => (y.Name), ), ))), ), )]
Any idea how to fix that without using ToList ?
The point is, that we should NOT call Count() over projection. So this will work
var query = repositoy.Query<MyClass>;
var list = query.Select(domain => new MyDto()
{
Id = domain.Id,
StringComma = string.Join(",", domain.MyList.Select(y => y.Name))
});
var count = query.Count();
When we use ICriteria query, the proper syntax would be
var criteria = ... // criteria, with WHERE, SELECT, ORDER BY...
// HERE cleaned up, just to contain WHERE clause
var totalCountCriteria = CriteriaTransformer.TransformToRowCount(criteria);
So, for Count - use the most simple query, i.e. containing the same JOINs and WHERE part
If you really don't need the results, but only the count, then you shouldn't even bother writing the .Select() clause. Radim's answer as posted is a good way to both get the results and the count, but if your database supports it, use future queries to execute both in the same roundtrip to the database:
var query = repository.Query<MyClass>;
var list = query.Select(domain => new MyDto()
{
Id = domain.Id,
StringComma = string.Join(",", domain.MyList.Select(y => y.Name))
}).ToFuture();
var countFuture = query.Count().ToFutureValue();
int actualCount = countFuture.Value; //queries are actually executed here
Note that there in NH prior to 3.3.3, this would still execute two round-trips (see https://nhibernate.jira.com/browse/NH-3184), but it would work, and if you ever upgrade NH, you get a (minor) performance boost.
Using QueryOver I am creating a query like this
BulkActionItem bulkActionItemAlias1 = null;
BulkActionItem bulkActionItemAlias2 = null;
var query = GetSession().QueryOver<Student>(() => studentAlias)
.JoinAlias(() => studentAlias.BulkNotifications, () => bulkActionItemAlias1, NHibernate.SqlCommand.JoinType.LeftOuterJoin);
if (query.UnderlyingCriteria.GetCriteriaByAlias("bulkActionItemAlias2") == null
query = query.JoinAlias(() => studentAlias.BulkNotifications, () => bulkActionItemAlias2, NHibernate.SqlCommand.JoinType.LeftOuterJoin);
This will crash because I have the same join twice with different aliases. Is it possible to check if a join already exists on a query, even with a different alias?
I haven't found a built-in way to accomplish this. Typically I use an out parameter with extension methods to keep track of what tables are part of the query. For example:
bool joinedOnBulkNotifications;
BulkNotification notificationAlias = null;
Expression<Func<object>> aliasExpr = () => notificationAlias;
var query = GetSession().QueryOver<Student>(() => studentAlias)
.FilterByBulkNotificationStatus(
someCondition, aliasExpr, out joinedOnBulkNotifications);
public static class QueryExtensions
{
public static IQueryOver<Student, Student> FilterByBulkNotificationStatus(
this IQueryOver<Student, Student> query,
bool someCondition,
Expression<Func<object>> aliasExpr,
out bool joinedOnBulkNotifications)
{
joinedOnBulkNotifications = false;
if (someCondition)
{
joinedOnBulkNotifications = true;
query.JoinAlias(s => s.BulkNotifications, aliasExpr);
}
return query;
}
}
The issue is that you might need to reuse the alias you created later. You might be tempted to pass in a BulkNotification and use that, but this only works if the parameter name matches the name of the variable you pass to the extension method. NHibernate uses the name of the variable to create an alias name, so if these two do not match, you'll get an error. Because of this, you need to wrap the alias in an Expression and use that instead.
This isn't a very clean option, so I hope someone has a better solution.
I hit a situation today where a field in our legacy db that should never be empty... was empty.
I am using NHibernate 3.2 against this database and the queries that are affected are written in QueryOver.
My current query is this
return Session
.QueryOver<FacilityGroup>()
.Where(fg => fg.Owner.Id == Token.OwnerId &&
fg.UserName == Token.UserName)
.OrderBy(fg => fg.Code).Asc
.TransformUsing(Transformers.DistinctRootEntity);
I want it to be this:
return Session
.QueryOver<FacilityGroup>()
.Where(fg => fg.Owner.Id == Token.OwnerId &&
fg.UserName == Token.UserName &&
!string.IsNullOrEmpty(fg.Code))
.OrderBy(fg => fg.Code).Asc
.TransformUsing(Transformers.DistinctRootEntity);
When I try this I get an exception "Unrecognised method call: System.String:Boolean IsNullOrEmpty(System.String)"
So NHibernate can't translate string.IsNullOrEmpty. Fair enough. However when I try this
return Session
.QueryOver<FacilityGroup>()
.Where(fg => fg.Owner.Id == Token.OwnerId &&
fg.UserName == Token.UserName &&
!(fg.Code == null || fg.Code.Trim() == "" ))
.OrderBy(fg => fg.Code).Asc
.TransformUsing(Transformers.DistinctRootEntity);
I get an InvalidOperationException "variable 'fg' of type 'Domain.Entities.FacilityGroup' referenced from scope '', but it is not defined"
Any thoughts?
Ok... I guess I asked this question too soon. I figured out a way around this.
What I was able to do was invoke the 'trim' function from hql via a SQL Function Projection. I ended up writing it as IQueryOver Extention method to keep it flexible. I will post it here in case anyone needs it.
public static class QueriesExtentions
{
public static IQueryOver<E, F> WhereStringIsNotNullOrEmpty<E, F>(this IQueryOver<E, F> query, Expression<Func<E, object>> propExpression)
{
var prop = Projections.Property(propExpression);
var criteria = Restrictions.Or(Restrictions.IsNull(prop), Restrictions.Eq(Projections.SqlFunction("trim", NHibernateUtil.String, prop), ""));
return query.Where(Restrictions.Not(criteria));
}
}
and here it is in use
return Session
.QueryOver<FacilityGroup>()
.Where(fg => fg.Owner.Id == Token.OwnerId && fg.UserName == Token.UserName )
.WhereStringIsNotNullOrEmpty(fg => fg.Code)
.OrderBy(fg => fg.Code).Asc
.TransformUsing(Transformers.DistinctRootEntity);