declare @d datetimeset @d=getdate()/*你的SQL脚本开始*/SELECT * FROM T_KNOWLEDGE WHERE KNOWLEDGE_TYPE_OID = 'c82d4ca4-9548-4274-bb80-d00d9a2fcd68' or KNOWLEDGE_TYPE_OID = 'f2917b90-a19e-4787-b27a-81038523d251'/*你的SQL脚本结束*/select [语句执行花费时间(毫秒)]=datediff(ms,@d,getdate()) set @d=getdate()/*你的SQL脚本开始*/SELECT * FROM T_KNOWLEDGE WHERE KNOWLEDGE_TYPE_OID in ( 'c82d4ca4-9548-4274-bb80-d00d9a2fcd68' , 'f2917b90-a19e-4787-b27a-81038523d251')/*你的SQL脚本结束*/select [语句执行花费时间(毫秒)]=datediff(ms,@d,getdate())

结论：in的时间会执行更长一点