SQL query to Fetchxml

Hello I want to convert following SQL query in FetchXML

select at.ava_name ,at.createdon
from ava_agreementtype at join ava_agreementtyperelation atr on at.ava_agreementtypeId=atr.ava_ChildId
join ava_agreement ag on atr.ava_ParentId=ag.ava_agreementtypeId
where ag.ava_AgreementId='0F8CA0AE-6D7F-E211-B35E-001DD8B825E8'

I tried following :

  var fetchXml = "<fetch distinct='false' mapping='logical' output-format='xml-platform' version='1.0'>" +
                 " <entity name='ava_agreementtype'>" +
                  "<attribute name='ava_agreementtypeid'/> <attribute name='ava_name'/> <attribute name='createdon'/>" +
                  " <order descending='false' attribute='ava_name'/>" +
                   "<link-entity name='ava_agreementtyperelation' from='ava_childid' to='ava_agreementtypeid' visible='false' link-type='outer' alias='ava_agreementtyperelation'>"+
                   " </link-entity>" +
                        "<link-entity name='ava_agreement' from='ava_agreementtypeid' to='ava_parentid' visible='false' link-type='outer'>"+
                             "<filter type='and'> <condition attribute='ava_agreementid' operator='eq' value='" + parentagreementid + "'/>" +                       
                         " </link-entity>" +                 
                   " </filter>" +
                   " </entity>" +
                   " </fetch>";

Its not working :(. Can someone pls help me regarding this.

Thanks in advance.