select (xpath('//Grading_Automated',(select xmlgrading from km_course_mast where id='100000'))) from km_course_mast where id='100000'
The out is below
"{"<Grading_Automated>
</Grading_Automated>"}"
The xpath return type is of type array. PG returns the array data, enclosed in "{}". If you want to remove these "{}" braces, then use either array_to_string(xpath(.......)) or trim the braces from the xpath output.
