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postgresql - sql - count of `true` values
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count(nullif(myCol, false)), -- count true values
count(myCol);
http://www.postgresql.org/docs/9.0/static/functions-conditional.html
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What good are SQL Server schemas?
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I tend to agree with Brent on this one... see this discussion here. http://www.brentozar.com/archive/2010/05/why-use-schemas/
In short... schemas aren't terribly useful except for very specific use cases. Makes things messy. Do not use them if you can help it. And try to obey the K(eep) I(t)...
if A vs if A is not None:
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The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation bool()...
Where can I get a “useful” C++ binary search algorithm?
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There is a set of them:
http://www.sgi.com/tech/stl/table_of_contents.html
Search for:
lower_bound
upper_bound
equal_range
binary_search
On a separate note:
They were probably thinking that searching containers could term up more than one resu...
Drop multiple tables in one shot in mysql
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Is there a way to make GHC provide the type class constraints of typed holes?
...ing, this isn't immediately obvious in GHCi. With your example,
> show _
<interactive>:7:6: error:
• Found hole: _h :: ()
Or perhaps ‘_h’ is mis-spelled, or not in scope
• In the first argument of ‘show’, namely ‘_h’
In the expression: show _h
I...
jsoncpp 不能处理__int64(long long)类型数据 - C/C++ - 清泛网 - 专注C/C++及内核技术
jsoncpp 不能处理__int64(long long)类型数据jsoncpp，是一个c++的解析和生成json的开源工具。如果你的c++程序需要解析或生成json，它会使这个过程变得很简单！但是，今天在用jsoncpp进...jsoncpp，是一个c++的解析和生成json的开源工具。如...
MongoDB仿关系型数据库Group聚合例子 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...数据
Dictionary dic = new Dictionary();
dic["_userName"] = ""; // 与原字段名区分开
dic["_date"] = "";
dic["_data"] = "0";
MongoServer server = new MongoClient(MongoConnStr).GetServer();
MongoDatabase db = serve...
How do I remove all .pyc files from a project?
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This ignores .pyo files and __pycache__ directories. See my answer.
– Wilfred Hughes
Apr 7 '14 at 15:03
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slashes in url variables
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Check out this w3schools page about "HTML URL Encoding Reference":
https://www.w3schools.com/tags/ref_urlencode.asp
for / you would escape with %2F
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