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Mysql varchar(255) 可以存放多少个汉字实验


这是一个有255个 “我”的字符串插入到 一个 设置为varchar(255)的实例代码

StringBuffer sb = new StringBuffer();
for(int i=0;i<256;i++){
sb.append("我");
}

PreparedStatement pstmt = conn_2.prepareStatement("insert into test_varchar values(?)");
pstmt.setString(1, sb.toString());
pstmt.execute();

实验结果:

  MySQL 数据库编码格式为 utf-8的情况下,一个varchar(255)就最多可以接受255个汉字。当将字符串增加到256时,出现  com.mysql.jdbc.MysqlDataTruncation: Data truncation: Data too long for column 'name' at row 1

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