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Null vs. False vs. 0 in PHP
...or a data value that doesn't exist in the database or is unknown. See dev.mysql.com/doc/refman/5.0/en/working-with-null.html or en.wikipedia.org/wiki/Null_%28SQL%29.
– Eli
Dec 5 '12 at 3:39
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Deep Learning（深度学习）学习笔记整理系列之（二） - 大数据 & AI - 清泛...
...，不妨把这个碎片标记为 T。
他们提出的问题是，如何从这400个碎片中，选取一组碎片，S[k], 通过叠加的办法，合成出一个新的碎片，而这个新的碎片，应当与随机选择的目标碎片 T，尽可能相似，同时，S[k] 的数量尽可...
【软著】软件著作权证书申请流程及注意事项，模板分享 - App Inventor 2 中...
...码文档中不要有代码空行及注释。50行*60页
6、AppInventor2如何申请软著？
一般的软件比如使用Java开发，源码中准备的就是.java代码，但是appinventor没有具体的代码怎么办？不要紧，将.aia导出后，用压缩软件打开aia源码，在src目...
How can I transform string to UTF-8 in C#?
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If you want to save any string to mysql database do this:->
Your database field structure i phpmyadmin [ or any other control panel] should set to utf8-gerneral-ci
2) you should change your string [Ex. textbox1.text] to byte, therefor
2-1) define byte[]...
How to change a nullable column to not nullable in a Rails migration?
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This worked for me. Using MySql locally. When pushed and ran app in Heroku (Postgres) it crapped on column that was not null when I was writing it a null - rightfully so. Only "change_column_null" would work could not use "change_column ... :null =>...
2016年最适合小投资的10个创业项目 - 资讯 - 清泛网 - 专注C/C++及内核技术
...，面对行行色色的创业项目让很多人挑花了眼，不知道该如何抉择。创业看似很难其实简单，抓住好项目你就勇敢之前！小投资创业项目是很多创业者的首选，面对行行色色的创业项目让很多人挑花了眼，不知道该如何抉择。小...
Does a foreign key automatically create an index?
... I'm just about positive that PostgreSQL creates an index. I'm pretty sure MySQL does. Making the index makes a ton of sense, but IT'T NOT REQUIRED. After all, why reference something if every time the DB goes to look it up it has to do a tablescan?
– MBCook
Ma...
SQL - using alias in Group By
...OUP BY is executed before the SELECT clause.
There are exceptions though: MySQL and Postgres seem to have additional smartness that allows it.
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外媒评本轮科技泡沫：创业公司首当其冲 九成将消失 - 资讯 - 清泛网 - 专注...
...部门主管安德鲁·博伊德（Andrew Boyd）说：“一家企业是如何从获风投支持的创业公司走过来的，目前不再有一个明确的界限。我们只是一家上市公司。”博伊德还补充说，富达国际目前有一个135人组成的分析师团队，这个团队...
Define: What is a HashSet?
...ontains and Remove.) HashSet also provides standard set operations such as union, intersection, and symmetric difference. Take a look here
There are different implementations of Sets. Some make insertion and lookup operations super fast by hashing elements. However, that means that the order in whi...