mysql server 版本:8.0.31


Q: 对于 mysql 协议,insert 的返回值里面包含什么信息?是否包含 insert_id?

A: 通过 wireshark 抓包,结果如下:

执行 sql:

INSERT IGNORE INTO `user` (`name`, `age`) VALUES ('1', 25), ('2', 25), ('2', 25);

mysql server 返回的内容如下:

Q:mysql 一次插入多行数据,获取的 insert_id 是第一行的 id 还是最后一行的 id?

A: 从上图可知,是第一个!mysql 的开发人员真是一群笨蛋!

图片.png


测试代码如下:

from loguru import logger
from peewee import *
import settings
from playhouse.shortcuts import ReconnectMixin
from pymysql.cursors import Cursor

host = settings.MYSQL_CONFIG.host
port = settings.MYSQL_CONFIG.port
username = settings.MYSQL_CONFIG.username
password = settings.MYSQL_CONFIG.password
database_name = settings.MYSQL_CONFIG.database_name


class ReconnectMySQLDatabase(ReconnectMixin, MySQLDatabase):
    pass


db = ReconnectMySQLDatabase(
    database=database_name,
    host=host,
    port=port,
    user=username,
    password=password,
    charset='utf8mb4'
)


class User(Model):
    name = CharField(unique=True)
    age = IntegerField()

    created_at = DateTimeField(
        null=False,
        constraints=[SQL('DEFAULT CURRENT_TIMESTAMP')],
        help_text='使用数据库时间'
    )
    updated_at = DateTimeField(
        null=False,
        constraints=[
            SQL('DEFAULT CURRENT_TIMESTAMP'),
            SQL('ON UPDATE CURRENT_TIMESTAMP'),
        ]
    )

    class Meta:
        database = db
        table_name = 'user'


model_set = [User]


db.drop_tables(model_set)
db.create_tables(model_set)


with db.cursor() as cursor:
    cursor: Cursor
    sql = """
    INSERT IGNORE INTO `user` (`name`, `age`) VALUES ('1', 25), ('2', 25), ('2', 25);
    """.strip()
    print('affected_rows: ', cursor.execute(sql))
    print('lastrowid: ',cursor.lastrowid)
    cursor.connection.commit()  # 这里必须要提交,不然所有的查询都会处于一个事务中

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