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postgresql - sql - count of `true` values
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In MySQL, you can do this as well:
SELECT count(*) AS total
, sum(myCol) AS countTrue --yes, you can add TRUEs as TRUE=1 and FALSE=0 !!
FROM yourTable
;
I think that in Postgres, this works:
SELECT count(*) AS total
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No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
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Set the JAVA_HOME environment variable to the JDK root folder - required if you run command line or maven (mvn).
(Search google for JAVA_HOME for more info)
In project properties in section Java Compiler select required JDK - if you run directly from eclipse
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ListCtrl 重绘（Custom Draw） - C/C++ - 清泛网 - 专注C/C++及内核技术
...处理＂重绘过程＂中所有的脏活了。
这篇文章的焦点是如何在一个LISTCTRL控件上使用Custom Draw消息。究其原因，一部分是因为我已经在我的工作上使用了Custom Draw有一段时间了，我很熟悉它。另一个原因是这个机制确实是非常好...
Sublime Text 3能用支持的插件推荐 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...方法不管用，可以看看我之前写的一篇文章，Sublime text 3如何安装package control办法。
此外，安装sublime text 3的插件还可以在github上下载源文件，解压后改名放到
C:\Users\Mr.DenGo(你的电脑名)\AppData\Roaming\Sublime Text 3\Packages 中
重启su...
How to specify an area name in an action link?
...r is to pass route Values, if you pass an empty parameter it will consider root structure and if you pass appropriate value it use it as area.
Also do not forget to use null or new{} as the 5th parameter because passing null or new {} while creating action link will not overload method for (text,ac...
Favorite Django Tips & Features?
...ttings.py
import os
PROJECT_DIR = os.path.dirname(__file__)
...
STATIC_DOC_ROOT = os.path.join(PROJECT_DIR, "static")
...
TEMPLATE_DIRS = (
os.path.join(PROJECT_DIR, "templates"),
)
Credits: I got this tip from the screencast 'Django From the Ground Up'.
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How to use a servlet filter in Java to change an incoming servlet request url?
...tyfierFilter implements Filter {
private static final String JSF_VIEW_ROOT_PATH = "/ui";
private static final String JSF_VIEW_SUFFIX = ".xhtml";
@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, Filte...
What's the difference between the data structure Tree and Graph?
...recursive pointer-based structure. The representation is not unique for unrooted trees, but that is immaterial.
– j_random_hacker
Jul 7 '14 at 9:42
2
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How do I test a file upload in rails?
...ctionDispatch::Http::UploadedFile.new({
:tempfile => File.new(Rails.root.join("test/fixtures/files/test.jpg"))
})
assert model.valid?
This way you can use the same methods you are using in your validations (as for example tempfile).
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How to use redis PUBLISH/SUBSCRIBE with nodejs to notify clients when data values change?
...but not least the sample code from media fire.
Install node.js+npm(as non root)
First you should(if you have not done this yet) install node.js+npm in 30 seconds (the right way because you should NOT run npm as root):
echo 'export PATH=$HOME/local/bin:$PATH' >> ~/.bashrc
. ~/.bashrc
mkdir ~...