今天看了別人的一篇文件，說的是循環提交，性能提高很多，我就用文章的存儲過程測試了一下，果然用時很少
create table t1 (a int ,b char(100));
創建load1
delimiter //
create procedure load1 (count INT UNSIGNED)
begin
declare s int unsigned default 1;
declare c char(80) default repeat('a',80);
while s <= count do
insert into t1 select null,c;
commit;
set s = s+1;
end while;
end //
delimiter ;
創建load2
delimiter //
create procedure load2 (count int unsigned)
begin
declare s int unsigned default 1;
declare c char(80) default repeat('a',80);
while s <= count do
insert into t1 select null,c;
set s = s+1;
end while;
end //
delimiter ;
創建load3
delimiter //
create procedure load3(count int unsigned)
begin
declare s int unsigned default 1;
declare c char(80) default repeat('a',80);
start transaction;
while s <= count do
insert into t1 select null,c;
set s = s+1;
end while;
commit;
end //
delimiter ;
mysql> create database db1;
Query OK, 1 row affected (0.00 sec)
mysql> use db1
Database changed
mysql> create table t1 (a int ,b char(100));
Query OK, 0 rows affected (0.03 sec)
mysql> call load1(20000);
Query OK, 0 rows affected (1 min 22.25 sec)
mysql> truncate table t1;
Query OK, 0 rows affected (0.02 sec)
mysql> truncate table t1;
Query OK, 0 rows affected (0.02 sec)
mysql> call load2(20000);
Query OK, 1 row affected (1 min 21.53 sec)
mysql> truncate table t1;
Query OK, 0 rows affected (0.02 sec)
mysql> call load3(20000);
Query OK, 0 rows affected (2.39 sec)
顯然，load3 方法要快的多，這是因爲每一次提交都要寫一次重做日誌，存儲過程 load1 和 load2
實際寫了 20000 次重做日誌文件，而對於存儲過程 load3 來說，實際只寫了一次。