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How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
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DbEntityValidationException - How can I easily tell what caused the error?
I have a project that uses Entity Framework. While calling SaveChanges on my DbContext , I get the following exception:
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Is there a way to take a screenshot using Java and save it to some sort of image?
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Believe it or not, you can actually use java.awt.Robot to "create an image containing pixels read from the screen." You can then write that image to a file on disk.
I just tried it, and the whole thing ends up like:
Rectangle screenRect = new Rectangle(T...
Override body style for content in an iframe
...e, I am hiding an element with a specific class in the inner iframe.
Basically, you just append a 'style' element to the 'head' of the inner iframe.
$('iframe').load( function() {
$('iframe').contents().find("head")
.append($("<style type='text/css'> .my-class{display:none;} <...
In c# is there a method to find the max of 3 numbers?
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Well, you can just call it twice:
int max3 = Math.Max(x, Math.Max(y, z));
If you find yourself doing this a lot, you could always write your own helper method... I would be happy enough seeing this in my code base once, but not regularly.
(N...
How can I replace text with CSS?
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display: none; doesn’t work because ::after really means “inside this element, but at the end”, in case anyone was curious.
– Ry-♦
Jun 30 '14 at 22:17
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How to determine if a record is just created or updated in after_save
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I was looking to use this for an after_save callback.
A simpler solution is to use id_changed? (since it won't change on update) or even created_at_changed? if timestamp columns are present.
Update: As @mitsy points out, if this check is needed outside of callbacks th...
How do I hotkey directly to File Search tab in Eclipse
...file search" in the search box. (If there are no results, and you have a really old Eclipse version, select the Include Unbound Commands check box.)
Put the caret into the Binding text box and press the key combination you want to use:
You can either re-use the CTRL+H binding (delete the other b...
JQuery Event for user pressing enter in a textbox?
...ler than that URL I posted. I wonder what the heck the article I posted is all about & why it takes so much code..
– CaptSaltyJack
Jun 29 '11 at 17:10
1
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Android get free size of internal/external memory
... size of free memory on internal/external storage of my device programmatically. I'm using this piece of code :
12 Answers
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