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CSS selector - element with a given child [duplicate]
I'm looking to make a selector which will select all elements if they have a specific child element. For example, select all <div> with a child <span> .
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How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
How to 'insert if not exists' in MySQL?
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Solution:
INSERT INTO `table` (`value1`, `value2`)
SELECT 'stuff for value1', 'stuff for value2' FROM DUAL
WHERE NOT EXISTS (SELECT * FROM `table`
WHERE `value1`='stuff for value1' AND `value2`='stuff for value2' LIMIT 1)
Explanation:
The innermost query
SELECT *...
Create an Android Jar library for distribution
...ormal Java project in Eclipse, add the android.jar to the build path, then select Export - Java - Jar File.
– Jeff Gilfelt
Feb 16 '11 at 10:47
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jQuery: select an element's class and id at the same time?
I've got some links that I want to select class and id at the same time.
6 Answers
6
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git selective revert local changes from a file
...fore checkout -p was introduced):
You can do it like this:
git add -i
(select the hunks you want to keep)
git commit -m "tmp"
Now you have a commit with only the changes you want to keep, and the rest is unstaged.
git reset --hard HEAD
At this point, uncommitted changes have been discarded...
How do I get SUM function in MySQL to return '0' if no values are found?
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Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
CSS3 selector :first-of-type with class name?
Is it possible to use the CSS3 selector :first-of-type to select the first element with a given class name? I haven't been successful with my test so I'm thinking it's not?
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JUnit 4 Test Suites
...lipse:
In the 'Package Explorer' view of the eclipse 'Java' perspective,
select your unit test(s) in their package, inside the eclipse java
project.
Right-click on any one of the selected tests.
In the pop-up menu, select New, Other…
Open the ‘Java’ folder, then open the ‘JUnit’ folder...
Linq to Entities join vs groupjoin
...Join syntax would be
from p in Parent
join c in Child on p.Id equals c.Id
select new { p.Value, c.ChildValue }
returning an IEnumerable<X> where X is an anonymous type with two properties, Value and ChildValue. This query syntax uses the Join method under the hood.
GroupJoin syntax would be
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