大约有 7,000 项符合查询结果(耗时:0.0229秒) [XML]
Is there any performance gain in indexing a boolean field?
...e an index, if you have too many records it doesn't use the index anyways.
MySQL not using index when checking = 1 , but using it with = 0
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What is SQL injection? [duplicate]
...d queries, or applying your language/toolkit's escaping functions (such as mysql_real_escape_string() in PHP).
Once you understand SQL Injection you'll get the joke behind this cartoon.
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How to pull a random record using Django's ORM?
...e backend you're using." - any experience on diffrent DB backends? (sqlite/mysql/postgres)?
– kender
Jun 8 '09 at 9:37
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使用App Inventor扩展实现多点触控:Scale Detector · App Inventor 2 中文网
...最终可能会将其包含在系统中。 同时,这篇笔记说明了如何使用 App Inventor 扩展来实现一个缩放检测器组件,人们可以使用它来创建对捏合和缩放手势做出反应的应用程序。
该说明在两个方面很有趣:
对于 App Inventor 用户,它...
How to implement the activity stream in a social network
...s to browse far back in time (if you even offer this)
I use a plain old MySQL table for dealing with about 15 million activities.
It looks something like this:
id
user_id (int)
activity_type (tinyint)
source_id (int)
parent_id (int)
parent_type (tinyint)
time ...
SQL WHERE condition is not equal to?
...uple of times.. but it didn't seem to work until I realized that DELETE in MySQL does not use the * ..
– Frank Vilea
May 27 '11 at 19:59
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Good Free Alternative To MS Access [closed]
...ess, you generally want a database server engine, like MS SQL, Postgresql, MySQL, Oracle, or their brethren. At the same time, those server engines are rarely if ever appropriate for a single-user desktop application.
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Deep Learning(深度学习)学习笔记整理系列之(四) - 大数据 & AI - 清泛...
...,这个AutoEncoder还不能用来分类数据,因为它还没有学习如何去连结一个输入和一个类。它只是学会了如何去重构或者复现它的输入而已。或者说,它只是学习获得了一个可以良好代表输入的特征,这个特征可以最大程度上代表...
Deep Learning(深度学习)学习笔记整理系列之(四) - 大数据 & AI - 清泛...
...,这个AutoEncoder还不能用来分类数据,因为它还没有学习如何去连结一个输入和一个类。它只是学会了如何去重构或者复现它的输入而已。或者说,它只是学习获得了一个可以良好代表输入的特征,这个特征可以最大程度上代表...
Deep Learning(深度学习)学习笔记整理系列之(四) - 大数据 & AI - 清泛...
...,这个AutoEncoder还不能用来分类数据,因为它还没有学习如何去连结一个输入和一个类。它只是学会了如何去重构或者复现它的输入而已。或者说,它只是学习获得了一个可以良好代表输入的特征,这个特征可以最大程度上代表...
