Comments on: Using SQL Functions in Criteria Restrictions

By: Davy Brion

Davy Brion — Tue, 05 May 2009 09:08:35 +0000

there are some functions that are registered per dialect that support multiple parameters though the way to use them with the Criteria API is probably a bit different… haven’t tried those yet

By: pho

pho — Tue, 05 May 2009 08:57:26 +0000

what about functions that need additional parameters, such as DATEPART or SUBSTRING? are those possible?

By: Davy Brion

Davy Brion — Mon, 04 May 2009 15:08:36 +0000

it’s not entirely db-specific, because these functions are registered per dialect and then map to their DB-specific implementation

if you use a function that’s only supported by one (or a couple of) dialect, then yes, you lose some db portability.

you can find the supported functions, and the db-specific implementation they map to, in the constructor of each dialect

By: marek

marek — Mon, 04 May 2009 15:05:22 +0000

Hi Davy,

what if the db doesn’t support the ‘year’ function?
Doesn’t your code become db-specific when you use this kind of syntax?

Thanks

By: Reflective Perspective - Chris Alcock » The Morning Brew #339

Reflective Perspective - Chris Alcock » The Morning Brew #339 — Fri, 01 May 2009 06:36:22 +0000

[...] Using SQL Functions in Criteria Restrictions – Davy Brion shows how despite the slightly unfriendly syntax it is possible to build criteria based queries in NHibernate that use the the built in functions of the database. [...]

By: den Ben

den Ben — Thu, 30 Apr 2009 13:42:26 +0000

get off my lawn you 2!!

By: Davy Brion

Davy Brion — Thu, 30 Apr 2009 12:49:08 +0000

i used to think so

By: Koen

Koen — Thu, 30 Apr 2009 12:46:22 +0000

1981 was a good year…