测试了下，结果不对啊，并没有给出合适的索引建议，是我使用不对吗？

[empo007]

mysql> show create table test\G *************************** 1. row *************************** Table: test Create Table: CREATE TABLE test ( id bigint(20) DEFAULT NULL, name char(10) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8 1 row in set (0.00 sec)

用下面的存储过程插入100000条数据

create procedure test() begin declare i bigint; set i=0; while i<100000 do insert into test values(i,cast(i as char(10))); set i=i+1; end while; end;//

mysql> SHOW TABLE STATUS\G *************************** 1. row *************************** Name: test Engine: InnoDB Version: 10 Row_format: Dynamic Rows: 99937 Avg_row_length: 47 Data_length: 4734976 Max_data_length: 0 Index_length: 0 Data_free: 4194304 Auto_increment: NULL Create_time: 2017-11-06 09:52:16 Update_time: 2017-11-06 11:53:32 Check_time: NULL Collation: utf8_general_ci Checksum: NULL Create_options: Comment: 1 row in set (0.00 sec)

[root@szxts10011040 sqladvisor]# cat sql.cnf [sqladvisor] username=graTemp password=***** host=***** port=50006 dbname=lych sqls=select * from lych.test where id=1000;

[root@szxts10011040 sqladvisor]# ./sqladvisor -f sql.cnf -v 1 2017-11-06 13:51:35 66459 [Note] 2017-11-06 13:51:35 66459 [Note] 第2步：开始解析where中的条件:(id = 1000)

2017-11-06 13:51:35 66459 [Note] show index from test

2017-11-06 13:51:35 66459 [Note] 第3步：SQLAdvisor结束！表中没有任何索引

[empo007]

刚才给表test增加了name列上的索引，但是从输出来看有几个问题：

2017-11-06 14:19:04 70885 [Note] 2017-11-06 14:19:04 70885 [Note] 第2步：开始解析where中的条件:(id = 1000)

2017-11-06 14:19:04 70885 [Note] show index from test

2017-11-06 14:19:04 70885 [Note] show table status like 'test'

2017-11-06 14:19:04 70885 [Note] select count(*) from ( select id from test FORCE INDEX( idx_1 ) order by name DESC limit 10000) test where (id = 1000)

2017-11-06 14:19:04 70885 [Note] 第3步：表test的行数:95821**,limit行数:10000,得到where条件中(id = 1000)的选择度:10000**

===>选择度应该是1，而不是10000

**2017-11-06 14:19:04 70885 [Note] 第4步：开始验证 字段id是不是主键。表名:test

2017-11-06 14:19:04 70885 [Note] show index from test where Key_name = 'PRIMARY' and Column_name ='id' and Seq_in_index = 1

2017-11-06 14:19:04 70885 [Note] 第5步：字段id不是主键。表名:test

2017-11-06 14:19:04 70885 [Note] 第6步：开始验证 字段id是不是主键。表名:test

2017-11-06 14:19:04 70885 [Note] show index from test where Key_name = 'PRIMARY' and Column_name ='id' and Seq_in_index = 1

2017-11-06 14:19:04 70885 [Note] 第7步：字段id不是主键。表名:test**

===>为什么验证是否是主键做了2次？

2017-11-06 14:19:04 70885 [Note] 第8步：开始验证表中是否已存在相关索引。表名:test, 字段名:id, 在索引中的位置:1

2017-11-06 14:19:04 70885 [Note] show index from test where Column_name ='id' and Seq_in_index =1

2017-11-06 14:19:04 70885 [Note] 第9步：开始输出表test索引优化建议:

2017-11-06 14:19:04 70885 [Note] Create_Index_SQL：alter table test add index idx_id(id)

2017-11-06 14:19:04 70885 [Note] 第10步: SQLAdvisor结束!