LIKEによるマッチングには引っかかるけど，MATCHによる全文検索では引っかからないケースがある．
ずっと困っているので，正しいクエリの書き方とか設定とかあったら教えてください．助けてくれ……．
mysql> set names 'utf8mb4' collate 'utf8mb4_bin';
Query OK, 0 rows affected (0.00 sec)
mysql> select * from test_table;
+----+-----------+--------------------------------------------------+
| id | title | description |
+----+-----------+--------------------------------------------------+
| 1 | test | test data. |
| 2 | 日本語 | これは日本語のデータです |
| 3 | emojis | there are various emojis such as 😇, 🙆 etc. |
+----+-----------+--------------------------------------------------+
3 rows in set (0.00 sec)
mysql> select * from test_table where match (description) against ('😇*' in boolean mode);
Empty set (0.00 sec)
mysql> select * from test_table where description like '%😇%';
+----+--------+--------------------------------------------------+
| id | title | description |
+----+--------+--------------------------------------------------+
| 3 | emojis | there are various emojis such as 😇, 🙆 etc. |
+----+--------+--------------------------------------------------+
1 row in set (0.00 sec)
mysql> select * from test_table where match (description) against ('😇,' in natural language mode);
+----+--------+--------------------------------------------------+
| id | title | description |
+----+--------+--------------------------------------------------+
| 3 | emojis | there are various emojis such as 😇, 🙆 etc. |
+----+--------+--------------------------------------------------+
1 row in set (0.00 sec)
mysql>
my.cnf の内容です．
[mysqld]
character-set-server = utf8mb4
innodb_ft_min_token_size = 1
innodb_ft_enable_stopword = off
ngram_token_size = 2
query_cache_type = 1
query_cache_size = 64M
query_cache_limit = 8M
innodb_buffer_pool_size = 256M
innodb_flush_log_at_trx_commit = 0
innodb_flush_method=O_DIRECT
innodb_log_buffer_size = 8M
innodb_log_file_size = 128M
table_open_cache = 32
max_connections = 128
[client]
再現用のmysqldumpです．
gist.github.com
