Comments on: Custom functions in LINQ

By: Mindscape Blog » Blog Archive » Spatial data queries in LightSpeed

Mindscape Blog » Blog Archive » Spatial data queries in LightSpeed — Tue, 28 Sep 2010 01:26:01 +0000

[...] need to teach it about the spatial methods you want to use.As we’ve discussed before, you can use the ServerFunctionDescriptor.Register method to map a CLR function to a SQL function. However, the SQL Server 2008 spatial methods aren’t normal SQL functions: they’re [...]

By: Mindscape Blog » Blog Archive » Querying enhancements in LINQ to LightSpeed 3

Mon, 11 Jan 2010 22:09:15 +0000

[...] Want to call a SQL function from your LINQ query, but we don’t provide a translation from a CLR method, or worse still there’s no corresponding CLR method at all? Now you can create a custom function mapping that allows you to keep writing strongly-typed LINQ queries and having the desired function appear in the SQL translation. Find out how here. [...]

By: John-Daniel Trask

John-Daniel Trask — Mon, 17 Aug 2009 05:18:56 +0000

Hi Joan,

We use WordPress because we consider it the best tool for the job (especially over what was available at the time a few years ago).

We’re now running 2.8.4 – the built in upgrade from the admin console means it’s a one click upgrade (something I’m not sure any .net blog does).

Cheers for the reminder to keep up to date however :-)

By: Joan Pons

Joan Pons — Thu, 13 Aug 2009 12:14:24 +0000

JFYI
http://www.darknet.org.uk/2009/08/wordpress-2-8-3-admin-reset-exploit/

By: Joan Pons

Joan Pons — Thu, 13 Aug 2009 12:12:48 +0000

WordPress ? why are you using a php blogging system ? you couln’d find any .Net alternative ?

By: Robert Echten

Robert Echten — Wed, 12 Aug 2009 22:31:21 +0000

Hi Ivan,

For the first point, I don’t have a specific implementation in mind, but I can imagine where an application would support multiple databases (for instance for different customers, where a customer would have a preference for a particular RDBMS), so I was thinking about the per-database-type basis.

Good to know that the “query operator” syntax works the same way. And also nice to know the name of the syntax ;-)

By: Ivan Towlson

Ivan Towlson — Tue, 11 Aug 2009 23:30:15 +0000

Hello Robert, and sorry for the delay in replying — for some reason WordPress stuck your comment in moderation but neglected to tell me about it…

1. At present we do not provide a way to register different translations for different database engines, but it would be easy for us to add this if it would be useful to you. Any additional info you can provide about the scenario would be useful e.g. would you need to register translations on a per-database-instance basis (e.g. you want to translate DateTime.ToLocalTime(), but the UDF is called TO_LOCAL_TIME in the Customers database and APPLY_TZ_OFFSET in the Logistics database, even though both are Oracle), or just on a per-database-type basis?

2. Yes, this should work fine in “query operator” syntax. Most of our testing has been with the “language integrated” syntax but they both boil down to the same thing and the tests we have done with “query operator” syntax have worked fine. Do let us know if you run into any bugs though!

By: Ivan Towlson

Ivan Towlson — Tue, 11 Aug 2009 20:53:22 +0000

I was using Soundex only as an example of a SQL function that wasn’t surfaced in .NET/LINQ — didn’t intend to suggest it was state of the art in sound-alike matching! Thanks for the pointers though!

By: mycall

mycall — Tue, 11 Aug 2009 20:38:30 +0000

Don’t use Soundex.. Double Metaphone, Levenshtein, n-grams or even ConceptNet would provide better results.

By: DotNetShoutout

DotNetShoutout — Tue, 11 Aug 2009 04:35:37 +0000

Custom functions in LINQ made easy with LightSpeed…

Thank you for submitting this cool story – Trackback from DotNetShoutout…