如果查看 mysql 中一条数据对应的索引值?

V2EX = way to explore

V2EX 是一个关于分享和探索的地方

For Existing Member Sign In

• 请不要在回答技术问题时复制粘贴 AI 生成的内容

This topic created in 2335 days ago, the information mentioned may be changed or developed.

比如这个表

create table user(
    id int primary key,
    age int,
    height int,
    weight int,
    name varchar(32)
)engine = innoDb;

创建一个联合索引:

create index idx_obj on user(age asc,height asc,weight asc)

我想看一下这个表中每一条数据对应的具体的索引值是多少? 怎么搞?

我试过用命令

mysql> SELECT * FROM mysql.innodb_index_stats a WHERE a.database_name = 'learn_sql' and a.table_name like '%user%';
+---------------+------------+------------+---------------------+--------------+------------+-------------+-----------------------------------+
| database_name | table_name | index_name | last_update         | stat_name    | stat_value | sample_size | stat_description                  |
+---------------+------------+------------+---------------------+--------------+------------+-------------+-----------------------------------+
| learn_sql     | user       | PRIMARY    | 2019-12-13 10:18:16 | n_diff_pfx01 |          5 |           1 | id                                |
| learn_sql     | user       | PRIMARY    | 2019-12-13 10:18:16 | n_leaf_pages |          1 |        NULL | Number of leaf pages in the index |
| learn_sql     | user       | PRIMARY    | 2019-12-13 10:18:16 | size         |          1 |        NULL | Number of pages in the index      |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | n_diff_pfx01 |          4 |           1 | age                               |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | n_diff_pfx02 |          5 |           1 | age,height                        |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | n_diff_pfx03 |          5 |           1 | age,height,weight                 |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | n_diff_pfx04 |          5 |           1 | age,height,weight,id              |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | n_leaf_pages |          1 |        NULL | Number of leaf pages in the index |
| learn_sql     | user       | idx_obj    | 2019-12-13 15:47:28 | size         |          1 |        NULL | Number of pages in the index      |
+---------------+------------+------------+---------------------+--------------+------------+-------------+-----------------------------------+
9 rows in set (0.00 sec)

mysql>

int

asc

索引

weight

6 replies • 2019-12-14 09:28:22 +08:00