SQL一个语句不会写，求高手

A表是物品表，有物品编号字段。（比如有记录001和002）B表是操作日志表，有物品编号字段跟A表对应，有操作时间字段和操作人字段（比如001有3条记录，第一个操作人是aaa，002有5条记录，第一个操作人是bbb）我要把...

From [MySQLdiscussion group] 2017-03-01 09:44:40 0  2  974

LINQ 为什么要延迟执行？

int[] scores = { 10, 90, 100, 30, 70, 29, 45 };  v...

From [MySQLdiscussion group] 2016-11-07 15:05:40 0  1  974

为什么大家都不推荐使用MySQL触发器而用存储过程？

不止一次在各大论坛，文章中看到大多数人不推荐触发器，统统推荐存储过程。这是为什么呢？现在的场景是：1000万数据，1万并发的规模。疑问：我的理解是：触发器本身就是特殊的存储过程，那么如果业务逻辑本身不需...

From [MySQLdiscussion group] 2017-04-17 14:49:37 0  3  973

mysql optimization - how to prevent full table updates in mysql

MySQL has a safe mode, but sometimes in business, you need to update multiple rows of records, but you want to...

From [MySQLdiscussion group] 2017-05-18 10:55:07 0  1  972

mysql关系数据库，实现删除记录是用逻辑删除还是物理删除？

比如，订单和商品的关系；订单正常来说，应该会将商品的（名字、价格等等）字段另外保存；如果我需要删除商品记录，使用物理删除也不会影响订单的信息；但是这样会出现其他问题吗？

From [MySQLdiscussion group] 2016-11-05 11:02:12 0  1  968

java - mysql single table pipeline 500W data multi-dimensional statistics solution

There is a flow table structure in the project as follows: id sdkVersion jarVersion countryCode imei createTim...

From [MySQLdiscussion group] 2017-05-19 10:07:03 0  4  967

单点失效 - mysql cluster 使用问题

请问对于以上配置，使用数据库连接时：mysqli_connect("ip","user","password","db")，应该填写哪个ip...

From [MySQLdiscussion group] 2017-04-17 14:41:26 0  1  967

sql的普通索引和复合索引的问题

假如我在字段A中创建普通单索引，然后又在字段A创建复合索引，但是A不是复合索引的初始列，现在我只用字段A作为查询条件进行查询，请问会用到索引么，还是全表查询

From [MySQLdiscussion group] 2017-03-08 09:48:34 0  1  967

How can PHP display SQL query results through an array? There are multiple query results, as shown in the figure. I want echo in forsearch

How can PHP display SQL query results through an array? There are multiple query results, as shown in the figu...

From [MySQLdiscussion group] 2020-10-19 22:58:03 0  1  966

Object reference not set to object instance error when configuring MySQL Server 8.0

I'm installing MySQLServer8.0.29 from the MySQL installer and while applying the configuration I get the error...

From [MySQLdiscussion group] 2024-03-26 00:24:43 0  1  965

mysql - OA中的权限一人任多部门的岗位 权限表结构设置

公司-》部门-》岗位 小李是A公司总经理 兼任B公司的副总经理 兼任B公司的研发中心总监 兼任B公司的公关中心 某部门的 经理 一个人可能身兼多个公司的多个部门的的多个岗位，这样的权限和关联怎么设置对合理

From [MySQLdiscussion group] 2017-04-17 13:23:36 0  3  964

Design multifunctional product tables with multiple parameters for various product types

I don't have much experience in table design. My goal is to create one or more product tables that meet the fo...

From [MySQLdiscussion group] 2023-10-18 17:44:13 0  2  962

Is there a length limit to self-growth?

The maximum value of SQL is not more than 60,000. What should I do if the self-growth exceeds this value?

From [MySQLdiscussion group] 2020-07-04 11:10:00 0  0  961

这条联合sql语句哪里错了？

((( SELECT a.log_id,`create_date`,`content`,`creator`,`belong_to_user`,a.customer_code,`follow_up_wa...

From [MySQLdiscussion group] 2017-03-06 10:14:24 0  2  961

MySQL floating point precision range and rounding

(www.sf.gg) is China's leading developer technology community. We hope to provide a pure, high-quality technic...

From [MySQLdiscussion group] 2017-05-18 10:51:23 0  3  961