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MySQL Results as comma separated list
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You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
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In mongoDb, how do you remove an array element by its index?
In the following example, assume the document is in the db.people collection.
8 Answers
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Why does Java's hashCode() in String use 31 as a multiplier?
Per the Java documentation, the hash code for a String object is computed as:
13 Answers
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Run an OLS regression with Pandas Data Frame
I have a pandas data frame and I would like to able to predict the values of column A from the values in columns B and C. Here is a toy example:
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Converting an object to a string
How can I convert a JavaScript object into a string?
36 Answers
36
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Using an image caption in Markdown Jekyll
I am hosting a Jekyll Blog on Github and write my posts with Markdown. When I am adding images, I do it the following way:
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What is the best way to detect a mobile device?
...similar to the CSS @media attribute? I would like to run a different script if the browser is on a handheld device.
59 An...
HTML/CSS: Making two floating divs the same height
I have a little peculiar problem that I currently solve using a table , see below. Basically, I want to have two divs take up 100% of the available width, but only take up as much vertical space as needed (which isn't really that obvious from the picture). The two should at all times have the exa...
线程访问窗口资源的问题 - C/C++ - 清泛网 - 专注C/C++及内核技术
...于一个线程当中。当你在B线程使用A线程的窗口对象指针pWnd，B线程对此对象指针做AssertValid时，会因为以下几种原因导致断言失败:
1. CHandleMap* pMap = afxMapHWND(); ASSERT(pMap != NULL)失败;该线程没有映射表。原因这个线程只是工...
Does JavaScript guarantee object property order?
...ules since ES2015, but it does not (always) follow the insertion order. Simply put, the iteration order is a combination of the insertion order for strings keys, and ascending order for number-like keys:
// key order: 1, foo, bar
const obj = { "foo": "foo", "1": "1", "bar": "bar" }
Using an array o...