Perform the same operation and return the updated entries:
UPDATE weather SET temp_lo = temp_lo+1, temp_hi = temp_lo+15, prcp = DEFAULT WHERE city = ‘San Francisco‘ AND date = ‘2003-07-03‘ RETURNING temp_lo, temp_hi, prcp;
update returning的是更新后的内容
原文：http://www.cnblogs.com/cdyboke/p/7490077.html