PostgreSQL Version 9.1,i have a table,\[code\]xmltest=# \d xmltest Table "public.xmltest" Column | Type | Modifiers ---------+---------+----------- id | integer | not null xmldata | xml | Indexes: "xmltest_pkey" PRIMARY KEY, btree (id)xmltest=# select * from xmltest; id | xmldata ----+--------------------------------------- 1 | <root> + | <child1>somedata for child1 </child1>+ | <child2>somedata for child2 </child2>+ | </root> (1 row)\[/code\]now how to update the value inside the element/tag child2,i don't prefer to update the whole column at once, is their a way to do update/add/delete that particular value of tag, if so please share 