mysql统计信息相关

最近RDS FOR MYSQL5.6的统计信息有问题，一些表明明的数据，但统计信息里去显示为空表，导致执行计划出错，查询效率很低，所以查看下相关的信息。

-- 查看服务器系统变量，实际上使用的变量的值
show variables like '%innodb_stats_auto_recalc%';
-- 查看服务器状态变量，运行服务器的统计和状态指标
show status like '%Uptime%'; -- MySQL服务器已经运行的秒数
-- 刷新参数
flush status;

-- 查看当前和打开过的表
show global status like 'open%_tables';

-- 清空表缓存
flush tables;

-- 重启innodb_stats_auto_recalc
set @innodb_stats_auto_recalc=OFF;
set @innodb_stats_auto_recalc=ON;

MySQL [database_name]> select count(1) as cnt from database_name.dw_std_yf_roomtype_position;
+---------+
| cnt     |
+---------+
| 1247196 |
+---------+
1 row in set (0.20 sec)

MySQL [database_name]> select * from mysql.innodb_table_stats where table_name='dw_std_yf_roomtype_position';
+---------------------+-----------------------------+---------------------+--------+----------------------+--------------------------+
| database_name       | table_name                  | last_update         | n_rows | clustered_index_size | sum_of_other_index_sizes |
+---------------------+-----------------------------+---------------------+--------+----------------------+--------------------------+
| database_name       | dw_std_yf_roomtype_position | 2019-08-01 02:07:24 |      0 |                    1 |                        3 |
+---------------------+-----------------------------+---------------------+--------+----------------------+--------------------------+
1 row in set (0.09 sec)

MySQL [database_name]> select * from information_schema.tables where table_schema = 'database_name' and table_name = 'dw_std_yf_roomtype_position';
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
| TABLE_CATALOG | TABLE_SCHEMA        | TABLE_NAME                  | TABLE_TYPE | ENGINE | VERSION | ROW_FORMAT | TABLE_ROWS | AVG_ROW_LENGTH | DATA_LENGTH | MAX_DATA_LENGTH | INDEX_LENGTH | DATA_FREE | AUTO_INCREMENT | CREATE_TIME         | UPDATE_TIME | CHECK_TIME | TABLE_COLLATION | CHECKSUM | CREATE_OPTIONS | TABLE_COMMENT                      | BLOCK_FORMAT |
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
| def           | database_name       | dw_std_yf_roomtype_position | BASE TABLE | InnoDB |      10 | Compact    |          0 |              0 |       16384 |               0 |        49152 |   4194304 |           NULL | 2018-01-25 16:55:06 | NULL        | NULL       | utf8_general_ci |     NULL |                | 801002002017_户型的检查部位        | Original     |
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
1 row in set (0.00 sec)

MySQL [database_name]> ANALYZE  table database_name.dw_std_yf_roomtype_position;
+-------------------------------------------------+---------+----------+----------+
| Table                                           | Op      | Msg_type | Msg_text |
+-------------------------------------------------+---------+----------+----------+
| database_name.dw_std_yf_roomtype_position       | analyze | status   | OK       |
+-------------------------------------------------+---------+----------+----------+
1 row in set (0.07 sec)

MySQL [database_name]> select * from mysql.innodb_table_stats where table_name='dw_std_yf_roomtype_position';
+---------------------+-----------------------------+---------------------+---------+----------------------+--------------------------+
| database_name       | table_name                  | last_update         | n_rows  | clustered_index_size | sum_of_other_index_sizes |
+---------------------+-----------------------------+---------------------+---------+----------------------+--------------------------+
| database_name       | dw_std_yf_roomtype_position | 2019-08-01 10:56:02 | 1157429 |                32640 |                    40192 |
+---------------------+-----------------------------+---------------------+---------+----------------------+--------------------------+
1 row in set (0.10 sec)

MySQL [database_name]> select * from information_schema.tables where table_schema = 'database_name' and table_name = 'dw_std_yf_roomtype_position';
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
| TABLE_CATALOG | TABLE_SCHEMA        | TABLE_NAME                  | TABLE_TYPE | ENGINE | VERSION | ROW_FORMAT | TABLE_ROWS | AVG_ROW_LENGTH | DATA_LENGTH | MAX_DATA_LENGTH | INDEX_LENGTH | DATA_FREE | AUTO_INCREMENT | CREATE_TIME         | UPDATE_TIME | CHECK_TIME | TABLE_COLLATION | CHECKSUM | CREATE_OPTIONS | TABLE_COMMENT                      | BLOCK_FORMAT |
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
| def           | database_name       | dw_std_yf_roomtype_position | BASE TABLE | InnoDB |      10 | Compact    |    1157429 |            462 |   534773760 |               0 |    658505728 |   4194304 |           NULL | 2018-01-25 16:55:06 | NULL        | NULL       | utf8_general_ci |     NULL |                | 801002002017_户型的检查部位        | Original     |
+---------------+---------------------+-----------------------------+------------+--------+---------+------------+------------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+------------------------------------+--------------+
1 row in set (0.00 sec)

MySQL [database_name]> show index from database_name.dw_std_yf_roomtype_position;
+-----------------------------+------------+--------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+
| Table                       | Non_unique | Key_name           | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible |
+-----------------------------+------------+--------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+
| dw_std_yf_roomtype_position |          0 | PRIMARY            |            1 | id          | A         |     1157429 |     NULL | NULL   |      | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          0 | PRIMARY            |            2 | db_name     | A         |     1157429 |     NULL | NULL   |      | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          1 | ix_position_id     |            1 | position_id | A         |       52610 |     NULL | NULL   | YES  | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          1 | ix_tenant_roomtype |            1 | roomtype_id | A         |      289357 |     NULL | NULL   | YES  | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          1 | ix_tenant_roomtype |            2 | db_name     | A         |      289357 |     NULL | NULL   |      | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          1 | ix_tenant_position |            1 | db_name     | A         |       12580 |     NULL | NULL   |      | BTREE      |         |               | YES     |
| dw_std_yf_roomtype_position |          1 | ix_tenant_position |            2 | position_id | A         |       44516 |     NULL | NULL   | YES  | BTREE      |         |               | YES     |
+-----------------------------+------------+--------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+

MySQL [database_name]> select * from mysql.innodb_index_stats where database_name='database_name' and table_name='dw_std_yf_roomtype_position';
+---------------------+-----------------------------+--------------------+---------------------+--------------+------------+-------------+-----------------------------------+
| database_name       | table_name                  | index_name         | last_update         | stat_name    | stat_value | sample_size | stat_description                  |
+---------------------+-----------------------------+--------------------+---------------------+--------------+------------+-------------+-----------------------------------+
| database_name       | dw_std_yf_roomtype_position | PRIMARY            | 2019-08-01 10:56:02 | n_diff_pfx01 |    1095171 |          20 | id                                |
| database_name       | dw_std_yf_roomtype_position | PRIMARY            | 2019-08-01 10:56:02 | n_diff_pfx02 |    1157429 |          20 | id,db_name                        |
| database_name       | dw_std_yf_roomtype_position | PRIMARY            | 2019-08-01 10:56:02 | n_leaf_pages |      28299 |        NULL | Number of leaf pages in the index |
| database_name       | dw_std_yf_roomtype_position | PRIMARY            | 2019-08-01 10:56:02 | size         |      32640 |        NULL | Number of pages in the index      |
| database_name       | dw_std_yf_roomtype_position | ix_position_id     | 2019-08-01 10:56:02 | n_diff_pfx01 |      25448 |          20 | position_id                       |
| database_name       | dw_std_yf_roomtype_position | ix_position_id     | 2019-08-01 10:56:02 | n_diff_pfx02 |    1345353 |          20 | position_id,id                    |
| database_name       | dw_std_yf_roomtype_position | ix_position_id     | 2019-08-01 10:56:02 | n_diff_pfx03 |    1239445 |          20 | position_id,id,db_name            |
| database_name       | dw_std_yf_roomtype_position | ix_position_id     | 2019-08-01 10:56:02 | n_leaf_pages |      10486 |        NULL | Number of leaf pages in the index |
| database_name       | dw_std_yf_roomtype_position | ix_position_id     | 2019-08-01 10:56:02 | size         |      12160 |        NULL | Number of pages in the index      |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_position | 2019-08-01 10:56:02 | n_diff_pfx01 |       6263 |          20 | db_name                           |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_position | 2019-08-01 10:56:02 | n_diff_pfx02 |      21960 |          20 | db_name,position_id               |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_position | 2019-08-01 10:56:02 | n_diff_pfx03 |    1369816 |          20 | db_name,position_id,id            |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_position | 2019-08-01 10:56:02 | n_leaf_pages |      10311 |        NULL | Number of leaf pages in the index |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_position | 2019-08-01 10:56:02 | size         |      11968 |        NULL | Number of pages in the index      |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_roomtype | 2019-08-01 10:56:02 | n_diff_pfx01 |     131679 |          20 | roomtype_id                       |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_roomtype | 2019-08-01 10:56:02 | n_diff_pfx02 |     125442 |          20 | roomtype_id,db_name               |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_roomtype | 2019-08-01 10:56:02 | n_diff_pfx03 |    1591935 |          20 | roomtype_id,db_name,id            |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_roomtype | 2019-08-01 10:56:02 | n_leaf_pages |      13861 |        NULL | Number of leaf pages in the index |
| database_name       | dw_std_yf_roomtype_position | ix_tenant_roomtype | 2019-08-01 10:56:02 | size         |      16064 |        NULL | Number of pages in the index      |
+---------------------+-----------------------------+--------------------+---------------------+--------------+------------+-------------+-----------------------------------+

ref: https://www.cnblogs.com/zengkefu/p/5634858.html
ref: https://www.cnblogs.com/justfortaste/p/3276363.html