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How to get first record in each group using Linq
...roup element by element.F1
into groups
select groups.OrderBy(p => p.F2).First();
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Delete with Join in MySQL
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Since you are selecting multiple tables, The table to delete from is no longer unambiguous. You need to select:
DELETE posts FROM posts
INNER JOIN projects ON projects.project_id = posts.project_id
WHERE projects.client_id = :client_id
...
Code snippet or shortcut to create a constructor in Visual Studio
...a C# project.
So how to make a constructor
Press Ctrl+K and then Ctrl+X
Select Visual C#
Select ctor
Press Tab
Update: You can also right-click in your code where you want the snippet, and select Insert Snippet from the right-click menu
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Can a Windows batch file determine its own file name?
...hat I find interesting is that %nx0 won't work, given that we know the '~' char usually is used to strip/trim quotes off of a variable.
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What is :: (double colon) in Python when subscripting sequences?
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TL;DR
This visual example will show you how to a neatly select elements in a NumPy Matrix (2 dimensional array) in a pretty entertaining way (I promise). Step 2 below illustrate the usage of that "double colons" :: in question.
(Caution: this is a NumPy array specific example with...
How to pass an array within a query string?
...)
Form Examples
On a form, multi-valued fields could take the form of a select box set to multiple:
<form>
<select multiple="multiple" name="cars[]">
<option>Volvo</option>
<option>Saab</option>
<option>Mercedes</option...
Purpose of memory alignment
...y you have a struct in memory that looks like this:
struct mystruct {
char c; // one byte
int i; // four bytes
short s; // two bytes
}
On a 32-bit processor it would most likely be aligned like shown here:
The processor can read each of these members in one transaction.
Say you...
How do I query using fields inside the new PostgreSQL JSON datatype?
... a comments below.
The answer to the original question in Postgres 9.3:
SELECT *
FROM json_array_elements(
'[{"name": "Toby", "occupation": "Software Engineer"},
{"name": "Zaphod", "occupation": "Galactic President"} ]'
) AS elem
WHERE elem->>'name' = 'Toby';
Advanced example:
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vim command to restructure/force text to 80 columns
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And it also works with visual selections. Ie something like: V}gq. In this way you see what you are going to format before actually formatting it.
– Plouff
Dec 2 '14 at 11:09
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How to style the parent element when hovering a child element?
I know that there does not exist a CSS parent selector , but is it possible to style a parenting element when hovering a child element without such a selector?
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