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How to set a default value for a datetime column to record creation time in a migration?
...e is a sample migration:
class CreatePosts < ActiveRecord::Migration[5.0]
def change
create_table :posts do |t|
t.datetime :modified_at, default: -> { 'CURRENT_TIMESTAMP' }
t.timestamps
end
end
end
See discussion at https://github.com/rails/rails/issues/27077 and an...
Convert PDF to clean SVG? [closed]
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answered Apr 23 '12 at 20:53
Saintt Sheldon PatnettSaintt Sheldon Patnett
1,12388 silver badges88 bronze badges
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How do I check CPU and Memory Usage in Java?
...ime.freeMemory();
sb.append("free memory: " + format.format(freeMemory / 1024) + "<br/>");
sb.append("allocated memory: " + format.format(allocatedMemory / 1024) + "<br/>");
sb.append("max memory: " + format.format(maxMemory / 1024) + "<br/>");
sb.append("total free memory: " + fo...
Is there a JavaScript function that can pad a string to get to a determined length?
... solution here and this is for me much much simpler:
var n = 123
String("00000" + n).slice(-5); // returns 00123
("00000" + n).slice(-5); // returns 00123
(" " + n).slice(-5); // returns " 123" (with two spaces)
And here I made an extension to the string object:
String.prototype.paddingLef...
Function for Factorial in Python
...actorial (available in Python 2.6 and above):
import math
math.factorial(1000)
If you want/have to write it yourself, you can use an iterative approach:
def factorial(n):
fact = 1
for num in range(2, n + 1):
fact *= num
return fact
or a recursive approach:
def factorial(n)...
How do you truncate all tables in a database using TSQL?
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For SQL 2005,
EXEC sp_MSForEachTable 'TRUNCATE TABLE ?'
Couple more links for 2000 and 2005/2008..
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Checking if an Android application is running in the background
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30 Answers
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How does JavaScript .prototype work?
I'm not that into dynamic programming languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
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Express next function, what is it really for?
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edited Oct 30 '12 at 5:33
answered Oct 30 '12 at 5:26
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