unicode collation examples

mysql> select @@version;
+-----------+
| @@version |
+-----------+
| 8.0.25    |
+-----------+
1 row in set (0.00 sec)

mysql> select "Hey! 🙂" = "Hey! 😡" collate utf8mb4_general_ci;
+------------------------------------------------+
| "Hey! ?" = "Hey! ?" collate utf8mb4_general_ci |
+------------------------------------------------+
|                                              1 |
+------------------------------------------------+
1 row in set (0.00 sec)

mysql> select "Hey! 🙂" = "Hey! 😡" collate utf8mb4_0900_ai_ci;
+------------------------------------------------+
| "Hey! ?" = "Hey! ?" collate utf8mb4_0900_ai_ci |
+------------------------------------------------+
|                                              0 |
+------------------------------------------------+
1 row in set (0.00 sec)

mysql> select "ß" = "ss" collate utf8mb4_general_ci;
+----------------------------------------+
| "ß" = "ss" collate utf8mb4_general_ci  |
+----------------------------------------+
|                                      0 |
+----------------------------------------+
1 row in set (0.00 sec)

mysql> select "ß" = "ss" collate utf8mb4_0900_ai_ci;
+----------------------------------------+
| "ß" = "ss" collate utf8mb4_0900_ai_ci  |
+----------------------------------------+
|                                      1 |
+----------------------------------------+
1 row in set (0.00 sec)

mysql> select "a" = "Ä" collate utf8mb4_general_ci;
+---------------------------------------+
| "a" = "Ä" collate utf8mb4_general_ci  |
+---------------------------------------+
|                                     1 |
+---------------------------------------+
1 row in set (0.00 sec)

mysql> select "a" = "Ä" collate utf8mb4_0900_as_ci;
+---------------------------------------+
| "a" = "Ä" collate utf8mb4_0900_as_ci  |
+---------------------------------------+
|                                     0 |
+---------------------------------------+
1 row in set (0.00 sec)