You can access Objects from external resources using the "from" keyword (in fact the use of this with Hibernate named queries is a documented use-case, IIRC).<br><br>The Objects are not however inserted into WorkingMemory using "from" are should therefore be time-constant as their properties will not be included in truth maintenance.<br>
<br>If you require the Objects as Facts in WorkingMemory for the inference engine to reason with, you can write rules using "from" that insert into WorkingMemory.<br><br><div class="gmail_quote">On 14 February 2011 11:27, hyjshanghai <span dir="ltr"><<a href="mailto:hyjshanghai@gmail.com">hyjshanghai@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><br>
As far as I know, Drools can only reason over facts in the working memory. It<br>
can not directly "select" from RDBMS. You have to load in all data items<br>
from the database and validate them in memory by Drools.<br>
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