Query and sort content from two lists using search API

Question

Hi,
I have a custom web part which I would like to query two different lists and sort the results by Created Date. One is a list of news articles and the other contains blogs. So basically the result set will be an intermix of news and blog items sorted by date.
I would also like to do this by query through the search API. Does anybody have any sample code to do this?
thanks,
Sherazad.
Sherazad

Answer 1

Hi Sherazad:
To use the JOIN operator in CAML, your lists must have a
defined relation(Lookup column). You can refer to sample code that I list as follow.
Create your query from one of your lists.
SPList Projects= SPContext.Current.Site.RootWeb.Lists["Projects"];
SPQuery query = new SPQuery();
To do the join, setquery.Joins
 <Join Type="INNER" ListAlias="Contacts">
    <Eq>
        <FieldRef Name="ProjectManager" RefType="ID" /> ///
ProjectManager is a Lookup Column.
        <FieldRef List="Contacts" Name="ID" />
    </Eq>
 </Join>
And query.ProjectedFields (To tell SharePoint how to project the lookup columns into the result)
<Field Name="Project Name" Type="Lookup" List="Projects" ShowField="Title">
/// My Project Name is a Display Name in Memory so you can give a name by yourself But ShowField must be Internal Name of the Column(Project Name)
You can add a lot of columns that you want to display.
Everything comes from memory.
To choose the fields to display set query.ViewFields
<FieldRef Name="Your Internal Name of Column Or
ProjectedFields - Field Name">
<FieldRef Name="Your Internal Name of Column Or
ProjectedFields - Field Name">
<FieldRef Name="Your Internal Name of Column Or
ProjectedFields - Field Name"> 
Then
SPListItemCollection result = ListA.GetItems(query);