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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
Are nested try/except blocks in python a good programming practice?
...EAFP.
Personally, I prefer to avoid nesting when it's not necessary:
def __getattribute__(self, item):
try:
return object.__getattribute__(item)
except AttributeError:
pass # fallback to dict
try:
return self.dict[item]
except KeyError:
raise Attrib...
Getting the name of a variable as a string
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OK, finally got it! Installed using the following pip3 install python-varname==0.1.5; imported using from varname import nameof
– enter_display_name_here
Jun 6 at 2:42
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Express-js can't GET my static files, why?
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In case of new install you should verify that your express module is properly installed (expressjs.com/en/starter/installing.html) then you should check the path and your directory name like Giacomo said ;)
– Spl2nky
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Get a CSS value with JavaScript
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Somewhat off topic: some (all?) shorthand css properties are not accessible in JavaScript. E.g. you can get padding-left but not padding. JSFiddle
– David Winiecki
May 9 '14 at 21:10
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Setting the selected value on a Django forms.ChoiceField
...rying to assign the selected value to a ChoiceField.
If you have already called super().__init__ in your Form class, you should update the form.initial dictionary, not the field.initial property. If you study form.initial (e.g. print self.initial after the call to super().__init__), it will contai...
Adding custom radio buttons in android
... option ..... how to remove that ... keeping the functionality intact .... All i am trying to achieve as i showed in my question ... Any further directions ! [Note:: please look at the updated question]
– Devrath
Oct 3 '13 at 16:41
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Parameterize an SQL IN clause
...er 7 and later will auto-parameterize queries, so using parameters isn't really necessary from a performance standpoint - it is, however, critical from a security standpoint - especially with user inputted data like this.
sh...
How do you get assembler output from C/C++ source in gcc?
.... The output file can be still be set by using the -o option.
gcc -S -o my_asm_output.s helloworld.c
Of course this only works if you have the original source.
An alternative if you only have the resultant object file is to use objdump, by setting the --disassemble option (or -d for the abbreviat...
mysql -> insert into tbl (select from another table) and some default values [duplicate]
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If you want to insert all the columns then
insert into def select * from abc;
here the number of columns in def should be equal to abc.
if you want to insert the subsets of columns then
insert into def (col1,col2, col3 ) select scol1,scol2,...