MySQL Enum Search is not respecting collation

[altmannmarcelo]

Description

Readyset enum matching is not taking into consideration field collation.

CREATE TABLE `employees` (
  `emp_no` int NOT NULL,
  `birth_date` date NOT NULL,
  `first_name` varchar(14) NOT NULL,
  `last_name` varchar(16) NOT NULL,
  `gender` enum('M','F') NOT NULL,
  `hire_date` date NOT NULL,
  PRIMARY KEY (`emp_no`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci

Table is using collation _ci

Select directly on upstream:

mysql> SELECT COUNT(*) FROM employees WHERE gender = 'm';
+----------+
| COUNT(*) |
+----------+
|   179973 |
+----------+
1 row in set (0,05 sec)

mysql> SELECT COUNT(*) FROM employees WHERE last_name = 'facello';
+----------+
| COUNT(*) |
+----------+
|      186 |
+----------+
1 row in set (0,05 sec)

Select on Readyset:

mysql> SELECT COUNT(*) FROM employees WHERE gender = 'm';
+----------+
| count(*) |
+----------+
|        0 |
+----------+
1 row in set (0,00 sec)

mysql> SELECT COUNT(*) FROM employees WHERE last_name = 'facello';
+----------+
| COUNT(*) |
+----------+
|      186 |
+----------+
1 row in set (0,05 sec)

Note: Collation is been taken into consideration to last_name

Change in user-visible behavior

Requires documentation change