ArcGIS javascript API setDefinitionExpression returns wrong result set

New to GIS and ArcGIS.

I am trying to use the javascript API setDefinitionExpression to limit the output of a FeatureLayer on the map; however, the result set returned by the function is incorrect. The function returns only one result set but when I try to run the same query on the either the ArcGIS server or the database server, there are 6 results.

Anyone know why this is the case? Thanks.