不同使用
SELECT COUNT()
against
SELECT FOUND_ROWS()
我知道,如果你有限制,如果你不使用限制,实际上会有任何区别,那么应该使用行文?
You will get the same result but in two different ways.
COUNT () is an aggregated function used in selecteding and grouping data.
FOUND_ROWS()是在后使用另一个选择,以获取有关情况的信息。
如果你只需要同联通电话公司(COUNT)接通的浏览量,就会更快。
与此类似:
select count(*) as number_of_rows from some_table where something = something group by something;
或
select * from some_table where something = something group by something;
select found_rows();
select count(*) from tablename
取得表名中各行数的最有效途径
SELECT FOUND_ROWS();
http://dev.mysql.com/doc/refman/5.1/en/information-Functions.html#Function_found-rows
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