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How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ble_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rena...
Significance of -pthread flag when compiling
...plied to both the compiling and linking stage while others don't use it at all and just pass -lpthread to the linking stage.
...
Watch multiple $scope attributes
...bject in scope.
$scope.$watchGroup(
[function () { return _this.$scope.ViewModel.Monitor1Scale; },
function () { return _this.$scope.ViewModel.Monitor2Scale; }],
function (newVal, oldVal, scope)
{
if (newVal != oldVal) {
...
Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
...
Default implementation for Object.GetHashCode()
...{
public class Object {
[MethodImpl(MethodImplOptions.InternalCall)]
internal static extern int InternalGetHashCode(object obj);
public virtual int GetHashCode() {
return InternalGetHashCode(this);
}
}
}
InternalGetHashCode is mapped to an Objec...
How to send SMS in Java
...
if all you want is simple notifications, many carriers support SMS via email; see SMS through E-Mail
share
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improve this answ...
Java how to replace 2 or more spaces with single space in string and delete leading and trailing spa
...
Try this:
String after = before.trim().replaceAll(" +", " ");
See also
String.trim()
Returns a copy of the string, with leading and trailing whitespace omitted.
regular-expressions.info/Repetition
No trim() regex
It's also possible to do this with just one re...
AngularJS access scope from outside js function
... over it: github.com/angular/angular.js/wiki/When-to-use-$scope.$apply(). _If you are doing if (!$scope.$$phase) $scope.$apply() it's because you are not high enough in the call stack._
– scheffield
Sep 29 '14 at 14:44
...
Eclipse IDE for Java - Full Dark Theme
...
Didn't really work for me, the background is off black and the majority of code is black so pretty unreadable :(
– serenskye
Mar 24 '14 at 9:45
...
Possible to perform cross-database queries with PostgreSQL?
...no longer supported, but if you need to do this in a pre-2013 Postgres installation, there is a function called dblink.
I've never used it, but it is maintained and distributed with the rest of PostgreSQL. If you're using the version of PostgreSQL that came with your Linux distro, you might need to...
