Oracle Differences between NVL and Coalesce
问题 Are there non obvious differences between NVL and Coalesce in Oracle? The obvious differences are that coalesce will return the first non null item in its parameter list whereas nvl only takes two parameters and returns the first if it is not null, otherwise it returns the second. It seems that NVL may just be a \'Base Case\" version of coalesce. Am I missing something? 回答1: COALESCE is more modern function that is a part of ANSI-92 standard. NVL is Oracle specific, it was introduced in 80 's