select count和select count的区别

select count和select count的区别 select count(*)count 什么意思和select * 有什么区别 SELECT select count(*) from 怎么使用 select count(1) from emp and select 4718 fromselect count select t.*和select *有什么不同 区分choice choose 和select select from 表 和select from [表]有什么不同? SELECT sum(1) FROM table;和SELECT count(1) FROM table;SELECT sum(1) FROM table;----------------累加'1'列的总和;SELECT count(1) FROM table;--------------统计'1'列的总条数;这里总和与总条数有何不同?应该是这样：如果：SE select count(*)和select (1)select count(*)返回所有满足条件的记录数,此时同select sum(1) 但是sum()可以传任意数字,负数、浮点数都可以,返回的值是传入值n*满足条件记录数m1、可以解释下这段话的含 $sql=SELECT count(*) as pcount FROM news 和$sql = UPDATE article SET这句是什么意思? 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 piease.select select()是什么? select your Select your