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Rails where condition using NOT NIL
..., so you really should just use the joins predicate:
Foo.joins(:bar)
Select * from Foo Inner Join Bars ...
But, for the record, if you want a "NOT NULL" condition simply use the not predicate:
Foo.includes(:bar).where.not(bars: {id: nil})
Select * from Foo Left Outer Join Bars on .. WHERE ...
What is the proper way to check if a string is empty in Perl?
...== and != operators are numeric comparison operators. They will attempt to convert both operands to integers before comparing them.
See the perlop man page for more information.
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What is the purpose of using -pedantic in GCC/G++ compiler?
...o issue warnings in such cases. Using the stricter
-pedantic-errors option converts such diagnostic warnings into errors that will cause compilation
to fail at such points. Only those non-ISO constructs that are required to be flagged by a conforming
compiler will generate warnings or errors.
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pdf2htmlEX实现pdf转html - 开源 & Github - 清泛网 - 专注C/C++及内核技术
... fstype bits in TTF/OTF fonts (default:0)
--process-type3 <int> convert Type 3 fonts for web (experimental) (default: 0)
--heps <fp> 合并文本的水平临界值，单位：像素(default: 1)
--veps <fp> vertical threshold for merging text, in p...
How to specify font attributes for all elements on an html web page?
...es use: *,:before,:after{font-family:inherit;} if you must use a universal selector, use inheritance instead.
– darcher
Jun 5 '15 at 16:15
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Android Studio/Intellij Idea: “Table of Contents” for a class
... File Structure).
It shows the list of members of the current class. Select an element you want to navigate to and press the Enter key or the F4 key. To easily locate an item in the
list, just start typing its name.
Also, as danny117 points out, you can use Alt/⌘+7 to show / hide the sam...
PHP + curl, HTTP POST sample code?
...ooking again at this answer, you can also replace your custom query string converter implementation with http_build_query, just give it the $fields array and it'll output a query string.
– user2629998
Nov 17 '14 at 11:54
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What is the difference between GitHub and gist?
...car is meant to drive to work", without mentioning that the beach car is a convertible.
– DavidS
Jan 24 '18 at 23:23
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.NET console application as Windows service
...ich is also what you need to change to the console application in order to convert it to a Windows Service.
Here are the changes you need to do:
Install the following NuGet packages
Install-Package Microsoft.Extensions.Hosting.WindowsServices -Version 3.1.0
Install-Package Microsoft.Extensions.Co...
How to construct a set out of list items in python?
...
Just note that the order of the elements in a list is generally lost when converting the list to a set since a set is inherently unordered. (One exception in CPython, though, seems to be if the list consists only of non-negative integers, but I assume this is a consequence of the implementation of ...