Merging Field Values From With Inner Join?

Hello Experts,

Been struggling with this issue all morning and beginning to get a headache.  Essentialy my problem is this.  I have a gridview control that ive bound to datasource where the select statement is using an inner join to retrieve textual info from one table in refernce to an object_id contained within both. i.e

SelectCommand="SELECT 'multiple fields from both tables'
FROM ZCRMTAB_ACTIVITY INNER JOIN ZCRMTAB_ACT_LOG
ON
ZCRMTAB_ACT_LOG.OBJECT_ID = ZCRMTAB_ACTIVITY.OBJECT_ID
WHERE (ZCRMTAB_ACTIVITY.REF_CUST_NO = @REF_CUST_NO)
ORDER BY ZCRMTAB_ACTIVITY.CREATED_AT DESC">

<SelectParameters>
<asp:QueryStringParameter Name="fieldName" QueryStringField="value" Type="String" />

My problem is that this returns individual row results and are displayed on individual lines.  Where the object_id is the same i want all the textual info to be displayed within the same row.

Does anyone know how i can accomplish this?

Thanks in advance