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How to count occurrences of a column value efficiently in SQL?
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SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) as cnt
FROM Students
GROUP BY ag...
Postgres manually alter sequence
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The parentheses are misplaced:
SELECT setval('payments_id_seq', 21, true); # next value will be 22
Otherwise you're calling setval with a single argument, while it requires two or three.
share
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How to click or tap on a TextView text
... to run a method on tapping or clicking a TextView line of text in an Android App.
8 Answers
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How to implement has_many :through relationships with Mongoid and mongodb?
Using this modified example from the Rails guides , how does one model a relational "has_many :through" association using mongoid?
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Changing an element's ID with jQuery
I need to change an element's ID using jQuery.
8 Answers
8
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How do I fetch a single model in Backbone?
...e;
return base + (base.charAt(base.length - 1) == '/' ? '' : '/') + this.id;
},
This approach assumes that you have implemented controllers with the hashbang in your URL like so, http://www.mydomain.com/#clocks/123 , but it should work even if you haven't yet.
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Append text to input field
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$('#input-field-id').val($('#input-field-id').val() + 'more text');
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input id="input-field-id" />
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Scrollview vertical and horizontal in android
...d solution:
Custom ScrollView:
package com.scrollable.view;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ScrollView;
public class VScroll extends ScrollView {
public VScroll(Context context, AttributeSet attrs, int ...
Compare two DataFrames and output their differences side-by-side
...n [24]: changed = ne_stacked[ne_stacked]
In [25]: changed.index.names = ['id', 'col']
In [26]: changed
Out[26]:
id col
1 score True
2 isEnrolled True
Comment True
dtype: bool
Here the first entry is the index and the second the columns which has been changed.
In [27]: ...
Understanding generators in Python
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Hmm I think you're right, at least according to a test of a few lines in Python 2.6. A generator expression returns an iterator (aka 'generator object'), not a generator.
– Craig McQueen
Dec 4 '09 at 1:34
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