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MySQL COUNT DISTINCT
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浅谈TCP优化 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...里就不一一说明了，有兴趣的读者可以自行查阅。
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如何调整「rwnd」到一个合理值
有很多人都遇到过网络传输速度过慢的问题，比如说明明是百兆网络，其最大传输数据的理论值怎么着也得有个十兆，但是实际情况却相距...
Insert, on duplicate update in PostgreSQL?
...rom an answer on Stack Overflow how to perform multiple updates at once in MySQL using the following syntax:
16 Answers
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Linux C/C++程序常用的调试手段及异常排查总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...所有变量命名是否可以保持一致性？缩进，换行，可读性如何？
（驼峰、下划线，这个根据公司或者谷歌等的编码规范去做，至于缩进、换行、注释等，可以在经常使用的ide上安装相关格式化插件）
是否涉及动态资源
是...
SQL how to make null values come last when sorting ascending
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@Martin Note this question is not tagged mysql. I provided a generalized solution - there are many different ways of doing the same thing across different dbs.
– RedFilter
Oct 16 '15 at 14:15
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How to properly create composite primary keys - MYSQL
...ep these as two distinct columns. You could use a two-column primay key in mysql ...PRIMARY KEY(id_a, id_b)... but I prefer using a two-column unique index, and having an auto-increment primary key field.
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Return rows in random order [duplicate]
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For MySQL use ORDER BY uuid(). (...for those arriving on this page via a generic search, like me!)
– Stan James
Jan 7 '12 at 4:15
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL?
9 Answers
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MySQL Removing Some Foreign keys
I have a table whose primary key is used in several other tables and has several foreign keys to other tables.
11 Answers
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Storing JSON in database vs. having a new column for each key
...figured it was worth an update.
When this question was originally posted, MySQL had no support for JSON data types and the support in PostgreSQL was in its infancy. Since 5.7, MySQL now supports a JSON data type (in a binary storage format), and PostgreSQL JSONB has matured significantly. Both prod...