mysql 存储特殊字符

-- 设置数据库字符集
ALTER DATABASE mydatabase CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 设置表字符集
ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 设置列字符集
ALTER TABLE mytable MODIFY mycolumn VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

jdbc:mysql://localhost:3306/mydatabase?useUnicode=yes&characterEncoding=UTF-8

SELECT * FROM mytable WHERE mycolumn COLLATE utf8mb4_unicode_ci = '特殊字符';

ResultSet rs = statement.executeQuery("SELECT * FROM mytable");
rs.setFetchSize(100);
ResultSetMetaData metaData = rs.getMetaData();
int columnCount = metaData.getColumnCount();
for (int i = 1; i <= columnCount; i++) {
    System.out.println(metaData.getColumnName(i) + "\t" + metaData.getColumnTypeName(i));
}