Hi Brian, Yes, that would work for Microsoft SqlServer, but remember that there are other databases out there. The problem is the same.
I downloaded the source code and I found out that there is still no support for functions. So you can't use ToLower, ToUpper, IndexOf, Substring, etc... inside your linq query until they are mapped. I lot of work I guess :( On Mon, Jul 6, 2009 at 11:21 PM, Brian DeMarzo <[email protected]> wrote: > > SQL is case sensitive or case insensitive by default, but it can be > changed on a per-query basis. See > > http://aspadvice.com/blogs/ssmith/archive/2007/09/30/Case-Sensitive-or-Insensitive-SQL-Query.aspx > > In theory, I guess NH.Linq can expand WHERE clauses to use this syntax > based on the StringComparison value, though it would be complicated by > the many different collation levels (see > http://msdn.microsoft.com/en-us/library/ms180175.aspx). > > In theory, the current thread culture and StringComparison value can > be combined to find the "best" collation... (!) Or you can just use == > or a stored procedure or custom query. > > > > > On Jul 6, 2:12 pm, Chad Lee <[email protected]> wrote: > > Calling ToLower() like you did would be the way to do it. That being > said, > > I don't think the parser is handling method calls to ToLower. A patch > would > > be welcome. > > > > On Mon, Jul 6, 2009 at 1:09 PM, André Carlucci <[email protected] > >wrote: > > > > > Hi guys, first, thanks for this great framework. > > > > > I have a similar problem concerning case-insensitive search. > > > > > First, there is no such thing as "case-insensitive by default". I'm > > > using Oracle and it does care about it. As nhibernate is database > > > independent, it should care too. > > > > > Also, the Equals() function beeing translated to "like" is also wrong, > > > since Equals means... well... equals. The result of having this > > > difference (== -> = and Equals -> like) will only make a lot of people > > > create low performing queries, nothing more. > > > > > I think the like operator should come in place when you call something > > > like: > > > > > var query = from p in session.Linq<User>() > > > where p.Name.Contains(name) > > > select p; > > > > > And guest what: it works! > > > > > The problem is when I want a case-insensitive query: > > > > > var query = from p in session.Linq<User>() > > > where p.Name.ToLower().Contains(name.ToLower()) > > > select p; > > > > > The result is: System.ArgumentOutOfRangeException : Index was out of > > > range. Must be non-negative and less than the size of the collection. > > > Parameter name: index. Glup! > > > > > So, when using a database that cares about case in like queries, how > > > to perform a case-insensitive query? > > > > > Thanks! > > > > > André Carlucci > > > > > On 2 abr, 01:33, Chad Lee <[email protected]> wrote: > > > > Calling the .Equals method on a string generates a like query as you > > > > discovered. If you want to generate a SQL =, just do: > > > > p.Email == userEmail > > > > > > As Fabio pointed out, I am not aware of any case-insensitive search > in > > > SQL > > > > server. It is all case-insensitive by default. > > > > > > On Tue, Mar 31, 2009 at 9:14 AM, Fabio Maulo <[email protected]> > > > wrote: > > > > > which is the SQL for caseInsensitive. > > > > > > > 2009/3/31 Robert Misiak <[email protected]> > > > > > > >> I am working on a project in which we're using session.Linq<T>() > to do > > > > >> a variety of searches using Lambda expressions. We don't even > have > > > > >> nHibernate exposed to our application - we have a service layer > with > > > > >> methods that take Expression<Func<T, bool>> as a parameter which > call > > > > >> session.Linq<T>() with the passed parameter. > > > > > > >> We have a large table which was performing very slowly, and our > DBA > > > > >> found the nHibernate was doing a SQL LIKE behind the scenes > instead of > > > > >> using "=" which was a contributor to the slow performance. The > Lambda > > > > >> expressions that were getting converted to a LIKE were like so: > > > > > > >> session.Linq<T>(p => p.Email.Equals(userEmail, > > > > >> StringComparison.InvariantCultureIgnoreCase)); > > > > > > >> This leads me to the following questions: > > > > > > >> 1. What is the preferred way to do a case-insensitive search using > > > > >> nHibernate.Linq? > > > > >> 2. Is this a bug or a feature? Are there any plans to change this > > > > >> behavior in the future? > > > > > > >> I think that it would be helpful if in future versions of > > > > >> nHibernate.Linq, behavior related to case-(in)sensitivity or using > SQL > > > > >> LIKE was more transparent to the developer. > > > > > > >> FYI, in the mean-time, we've switched most of our simple queries > to > > > > >> use CreateCriteria(). > > > > > > >> Regards, > > > > >> Robert Misiak > > > > > > > -- > > > > > Fabio Maulo- Ocultar texto das mensagens anteriores - > > > > > > - Mostrar texto das mensagens anteriores - > > > > > > > > -- André Carlucci --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "NHibernate Contrib - Development Group" group. 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