4 rows in set (0.00 sec) mysql> truncate t12; Query OK, 0 rows affected (0.16 sec) mysql> insert into t12(name) values('Jack'),('Tom'),('Mark'),('Black'); Query OK, 4 rows affected (0.01 sec) Records: 4 Duplicates: 0 Warnings: 0 mysql> select * from t12; +---+---+ ...
Query OK,0 rows affected(1 min 3.15 sec) mysql>TRUNCATE TABLE t1; Query OK,0 rows affected(0.05 sec) mysql>CALL load2(10000); Query OK,1 row affected(1 min 1.69 sec) mysql>TRUNCATE TABLE t1; Query OK,0 rows affected(0.05 sec) mysql>CALL load3(10000); Query OK,0 rows affected(0...
--需要归档的数据量mysql admin@192.168.58.3:employees>selectcount(*)fromemployeeswherefirst_name='Anneke';+---+|count(*)|+---+|225|+---+1rowinsetTime:0.025s--执行归档操作# pt-archiver--source h=192.168.58.3,P=3306,u=admin,D=employees,t=employees,A=utf8 --dest h=192.168.58.3,P=3...
Re: How to update and delete rows in two tables at one query? Rick James July 01, 2010 07:48AM Re: How to update and delete rows in two tables at one query? sushant paste July 02, 2010 12:34PM Sorry, you can't reply to this topic. It has been closed....
delete from tu where id in (3,4); Query OK, 2 rows affected (0.00 sec) ---TRANSACTION 146880, ACTIVE 1 sec 2 lock struct(s), heap size 360, 2 row lock(s), undo log entries 2 MySQL thread id 1, OS thread handle 0x7f61ab1c7700, query id 928 localhost msandbox cleaning up ...
in set (0.01 sec) #重置状态变量计数 mysql> flush status; Query OK, 0 rows affected (0.01 sec) mysql> select id, age ,phone from user where name like 'lyn12%'; Empty set (0.05 sec) mysql> explain select id, age ,phone from user where name like 'lyn12%'; +---+---+---+-...
mysql>create tableundo_demo(->id int notnull,->key1varchar(100),->colvarchar(100),->primarykey(id),->keyidx_key1(key1)->);QueryOK,0rowsaffected(0.05sec) 表中id主键,key1是二级索引,col是普通列。我们前面说过每个表都有一个唯一的table id,在information_Shcema中的innodb_sys_tables。
最近,在脉脉上看到一个楼主提出的问题:MySQL数据量大时,delete操作无法命中索引;并且还附上了相关案例截图。 最终,楼主通过开启MySQL分析优化器追踪,定位到是优化器搞的鬼,它觉得花费时间太长。因为我这个是测试数据,究其原因是因为数据倾斜,导致计算出的数据占比较大、花费时间长。
mysql> show table status like 't_user'G *** 1. row *** Name: t_user Engine: InnoDB Version: 10 Row_format: Dynamic Rows: 4333 Avg_row_length: 589 Data_length: 2555904 Max_data_length: 0 Index_length: 2719744 Data_free: 4194304 Auto_increment: NULL Create_time: 2021-11-19 ...
TRANSACTION 272174, ACTIVE 0 sec fetching rows mysql tables in use 1, locked 1 LOCK WAIT 18 lock struct(s), heap size 1136, 58 row lock(s), undo log entries 41 MySQL thread id 298, OS thread handle 140425685493504, query id 5479767 172.18.70.114 root updating ...