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Using DISTINCT and COUNT together in a MySQL Query
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use
SELECT COUNT(DISTINCT productId) from table_name WHERE keyword='$keyword'
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Elegant ways to support equivalence (“equality”) in Python classes
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Consider this simple problem:
class Number:
def __init__(self, number):
self.number = number
n1 = Number(1)
n2 = Number(1)
n1 == n2 # False -- oops
So, Python by default uses the object identifiers for comparis...
IOS: create a UIImage or UIImageView with rounded corners
...iew with rounded corners? Because I want take an UIImage and show it inside an UIImageView , but I don't know how to do it.
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android layout: This tag and its children can be replaced by one and a compound drawable
... Romain Guy's answer, here is an example.
Before:
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:padding="5dp" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
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How to access maven.build.timestamp for resource filtering
...it to something newer, fixed it for me, 3.x ex:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<properties><timestamp>... workaround is no lon...
Change a Django form field to a hidden field
...alue.
also you may prefer to use in the view:
form.fields['field_name'].widget = forms.HiddenInput()
but I'm not sure it will protect save method on post.
Hope it helps.
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NSInvocation for Dummies?
...ting an NSInvocation object to say: "Hey, if you want to undo what I just did, send this message to that object, with these arguments". You give the NSInvocation object to the NSUndoManager, and it adds that object to an array of undoable actions. If the user calls "Undo", NSUndoManager simply looks...
.htaccess rewrite to redirect root URL to subdirectory
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Just recently I spent a lot of time debugging why this didn't work on a site in Ubuntu Apache 2.4.7. Rewrite debugging showed the rule being hit and generating an INTERNAL REDIRECT. Then it seemed to just park that and look for an index page. Turns out that if mod_dir is enabled A...
Set cursor position on contentEditable
...e with the standards-based browsers, but will probably fail in IE. I'm providing it as a starting point. IE doesn't support DOM Range.
var editable = document.getElementById('editable'),
selection, range;
// Populates selection and range variables
var captureSelection = function(e) {
// Do...
MySQL vs MongoDB 1000 reads
...sts in MySQL with about 20 million records indexed only on a field called 'id'.
7 Answers
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