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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
...
Date vs DateTime
...ortion of the value.
public static void Main()
{
System.DateTime _Now = DateAndTime.Now;
Console.WriteLine("The Date and Time is " + _Now);
//will return the date and time
Console.WriteLine("The Date Only is " + _Now.Date);
//will return only the date
Console.Write("Pres...
Can I have multiple :before pseudo-elements for the same element?
... normal element. In your example, the end result looks like this:
.circle.now:before {
content: "Now";
font-size: 19px;
color: black;
}
As you can see, only the content declaration that has highest precedence (as mentioned, the one that comes last) will take effect — the rest of the...
How to “properly” create a custom object in JavaScript?
...ype.toString= function() {
return 'Shape at '+this.x+', '+this.y;
};
Now to subclass it, in as much as you can call what JavaScript does subclassing. We do that by completely replacing that weird magic prototype property:
function Circle(x, y, r) {
Shape.call(this, x, y); // invoke the ba...
How to secure MongoDB with username and password
...
I have tried that and followed the example. now.. i can set it after I restart the server with --auth. However, when I try to login (./mongo -u theadmin -p 12345 ) I fail. I can't login.
– murvinlai
Feb 3 '11 at 0:10
...
Getting GDB to save a list of breakpoints
...
As of GDB 7.2 (2011-08-23) you can now use the save breakpoints command.
save breakpoints <filename>
Save all current breakpoint definitions to a file suitable for use
in a later debugging session. To read the saved breakpoint
definitions, use th...
How can I add or update a query string parameter?
...
Update (2020): URLSearchParams is now supported by all modern browsers.
The URLSearchParams utility can be useful for this in combination with window.location.search. For example:
if ('URLSearchParams' in window) {
var searchParams = new URLSearchParams(w...
git pull fails “unable to resolve reference” “unable to update local ref”
...
Try cleaning-up your local repository with:
$ git gc --prune=now
$ git remote prune origin
man git-gc(1):
git-gc - Cleanup unnecessary files and optimize the local repository
git gc [--aggressive] [--auto] [--quiet] [--prune=<date> | --no-prune]
Runs a number of hou...
Programmatically add custom event in the iPhone Calendar
...te the event handling inside of a block.
2) You need to commit your event now or pass the "commit" param to your save/remove call
Everything else stays the same...
Add the EventKit framework and #import <EventKit/EventKit.h> to your code.
In my example, I have a NSString *savedEventId inst...
Android App Not Install. An existing package by the same name with a conflicting signature is alread
...om another SDK, the keys will definitely be different.
Also if you don't know exactly what key was used before to sign the apk and yet you want to install the new version of your app, you can just uninstall the previous application and reinstall the new one.
Hope this Helps...
Regards!
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