select count(*)count 什么意思和select * 有什么区别

select count和select count的区别 select count(*)count 什么意思和select * 有什么区别 select count(*) from 怎么使用 select count(1) from emp and select 4718 fromselect count count count COUNT count count count count select telnum,count(0),count(distinct othertelnum) from nmk.ljdx_cdr_temp group by telnum select Count(0) from MbrMember where 1=1Count(0)where 1=1 count+=count++是什么意思? count,count和count的区别 count是什么意思 count是什么意思