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Error installing mysql2: Failed to build gem native extension
I am having some problems when trying to install mysql2 gem for Rails. When I try to install it by running bundle install or gem install mysql2 it gives me the following error:
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How do I create a user with the same privileges as root in MySQL/MariaDB? [closed]
How do I create a user with the same privileges as root in MySQL/MariaDB?.
1 Answer
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Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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How to create a database from shell command?
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cat filename.sql | mysql -u username -p # type mysql password when asked for it
Where filename.sql holds all the sql to create your database. Or...
echo "create database `database-name`" | mysql -u username -p
If you really only want to cr...
MongoDB: Combine data from multiple collections into one..how?
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Doing unions in MongoDB in a 'SQL UNION' fashion is possible using aggregations along with lookups, in a single query. Here is an example I have tested that works with MongoDB 4.0:
// Create employees data for testing the union.
d...
App Launcher 应用启动器扩展：用于启动其他应用程序的强大工具，支持独立...
...制造商用户注意：
对于小米设备，无论安装的Android版本如何，如果应用程序想在后台运行时启动另一个应用程序，都需要额外的权限。此权限无法通过程序设置，必须通过对话框由用户确认（参见 Android 10和小米设备的额外权...
PreparedStatement IN clause alternatives?
...in select or DML, since it is Oracle, which offers lightyears of more than MySQL or similar simple database engines. PL/SQL allows you to hide the storage model from your application domain model in an effective way.
The trick here is:
we need a call which accepts the long string, and store somewh...
CGRidCtrl控件 学习心得 - C/C++ - 清泛网 - 专注C/C++及内核技术
...编辑操作。扩充的两个类CgridCellCombo和CGridLCellCheck示范了如何创建自己的单元格类。
图2
单元格有两种主要状态即固定和非固定。固定的单元格通常在Grid的左上方，并且不会随着Grid的卷动而移动，并且不能进行编辑，通常即...
libevent对比libev的基准测试 - C/C++ - 清泛网 - 专注C/C++及内核技术
...libevent 每次迭代的总时间增加得快得多，无论客户端数量如何，花费的时间几乎是 libev 的两倍。不过，两者都表现出相似的增长特征。
轮询时间也非常相似，libevent 在 1000-fd 情况下始终较慢，而在 100-fd 情况下，时间几乎相同...
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
...rence between INNER JOIN , LEFT JOIN , RIGHT JOIN and FULL JOIN
in MySQL ?
3 Answers
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