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SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
MySQL has something like this:
5 Answers
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How do I write LINQ's .Skip(1000).Take(100) in pure SQL?
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No, but you could emulate MySQL's LIMIT clause (Stack Overflow link) to achieve the same result.
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...th on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!
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GestureDetect 手势检测扩展：识别滑动、点击和长按手势 · App Inventor 2 中文网
...作用？
Q: 可以在滚动排列中使用吗？
Q: 如何在同一个组件上检测多种手势？
Q: 可以自定义手势的灵敏度吗？
Q: 支持哪些布局组件？
Q: 如何实现更复杂的图片滑动功能？
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Get environment variable value in Dockerfile
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add -e key for passing environment variables to container.
example:
$ MYSQLHOSTIP=$(sudo docker inspect -format="{{ .NetworkSettings.IPAddress }}" $MYSQL_CONRAINER_ID)
$ sudo docker run -e DBIP=$MYSQLHOSTIP -i -t myimage /bin/bash
root@87f235949a13:/# echo $DBIP
172.17.0.2
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How to add not null constraint to existing column in MySQL
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Oddly I was getting an error (MySQL 5.6, Workbench 6.3) changing/modifying a column I'd named null_heart_rate_count, error was #1138, Invalid use of NULL value. I had to drop and add the column instead.
– William T. Mallard
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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...
mysql update column with value from another table
I have two tables, both looking like
8 Answers
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Laravel Eloquent ORM Transactions
...t ORM is quite nice, though I'm wondering if there is an easy way to setup MySQL transactions using innoDB in the same fashion as PDO, or if I would have to extend the ORM to make this possible?
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转型产品经理必看 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...文章。创办人人都是产品经理以来，每天都有很多人问我如何转型做产品经理、转型产品经理会遇到哪些问题，其实我一直没能回答好这个问题，因为我从运营转型产品经理的过程太顺利，并且转型的过程也没有做太多的思考和...