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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...
How do you use bcrypt for hashing passwords in PHP?
...d salts (bcrypt REQUIRES salts) and you can be sure that an attack is virtually unfeasible without either ludicrous amount of funds or hardware.
bcrypt uses the Eksblowfish algorithm to hash passwords. While the encryption phase of Eksblowfish and Blowfish are exactly the same, the key schedule pha...
What is the difference between is_a and instanceof?
...ut PHP versions >= 5.3.9 now accept an optional third boolean argument $allow_string (defaults to false) to allow comparisons of string class names instead:
class MyBaseClass {}
class MyExtendingClass extends MyBaseClass {}
// Original behavior, evaluates to false.
is_a(MyExtendingClass::class,...
Calculate age given the birth date in the format YYYYMMDD
...
@RobG I don't think a full year technically has passed from 2000-02-29 to 2001-02-28, making your answer invalid. It wouldn't make sense, 2000-02-28 to 2001-02-28 is a year, so 2000-02-29 to 2001-02-28, must be less than a year.
– André Sne...
How do I convert a Ruby class name to a underscore-delimited symbol?
...ow can I programmatically turn a class name, FooBar , into a symbol, :foo_bar ? e.g. something like this, but that handles camel case properly?
...
UnicodeDecodeError: 'utf8' codec can't decode byte 0xa5 in position 0: invalid start byte
...
I switched this simply by defining a different codec package in the read_csv() command:
encoding = 'unicode_escape'
Eg:
import pandas as pd
data = pd.read_csv(filename, encoding= 'unicode_escape')
share
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CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注IT技能提升
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注IT技能提升
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注IT技能提升
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注IT技能提升
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...