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CodeFile vs CodeBehind
...bute of the Page directive or is there a way to create a web project which selects codebehind or codefile, by default, each time a new web page is added?
– Matt W
Nov 5 '09 at 8:42
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Removing all empty elements from a hash / YAML?
...mplementation is not recursive. As a curiosity, they implemented it using #select instead of #delete_if for performance reasons. See here for the benchmark.
In case you want to backport it to your Rails 3 app:
# config/initializers/rails4_backports.rb
class Hash
# as implemented in Rails 4
# ...
Rails where condition using NOT NIL
..., so you really should just use the joins predicate:
Foo.joins(:bar)
Select * from Foo Inner Join Bars ...
But, for the record, if you want a "NOT NULL" condition simply use the not predicate:
Foo.includes(:bar).where.not(bars: {id: nil})
Select * from Foo Left Outer Join Bars on .. WHERE ...
How to create cron job using PHP?
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Type the following in the linux/ubuntu terminal
crontab -e
select an editor (sometime it asks for the editor)
and this to run for every minute
* * * * * /usr/bin/php path/to/cron.php &> /dev/null
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How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...
Creating a dynamic choice field
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@Ashok How could the CheckboxSelectMultiple widget be used in this instance? For the modelform especially.
– wasabigeek
Aug 14 '15 at 18:22
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Oracle find a constraint
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select * from all_constraints
where owner = '<NAME>'
and constraint_name = 'SYS_C00381400'
/
Like all data dictionary views, this a USER_CONSTRAINTS view if you just want to check your current schema and a DBA_CONSTRA...
A CSS selector to get last visible div
A tricky CSS selector question, don't know if it's even possible.
10 Answers
10
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Is there a CSS selector for elements containing certain text?
I am looking for a CSS selector for the following table:
18 Answers
18
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Is it a good idea to index datetime field in mysql?
...ne table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
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