Amazon Aurora只读副本中未更新索引统计信息

Question

当我插入数据时，会更新writer DB Indices统计信息 但是，不会更新Reader DB Indices统计信息。

示例就在这里。

数据库中。

create database test;

表。

CREATE TABLE test(
test_id INT NOT NULL PRIMARY KEY,
test_txt CHAR(8) DEFAULT NULL,
INDEX test_txt(test_txt)
);

作家。

mysql> insert into test values(1, 'test1');
Query OK, 1 row affected (0.01 sec)

mysql> show index from test;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| test  |          0 | PRIMARY  |            1 | test_id     | A         |           1 |     NULL | NULL   |      | BTREE      |         |               |
| test  |          1 | test_txt |            1 | test_txt    | A         |           1 |     NULL | NULL   | YES  | BTREE      |         |               |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
2 rows in set (0.00 sec)

阅读器。

mysql> show index from test;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| test  |          0 | PRIMARY  |            1 | test_id     | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| test  |          1 | test_txt |            1 | test_txt    | A         |           0 |     NULL | NULL   | YES  | BTREE      |         |               |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
2 rows in set (0.00 sec)

为什么基数不仅仅更新了读者？ 参数组是默认值。

请告诉我原因。