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Ruby 'require' error: cannot load such file
...start your Ruby process from a different directory, you'll have to rethink all of those require statements.
Using require to access files that are on the load path is a fine thing and Ruby gems do it all the time. But you shouldn't start the argument to require with a . unless you are doing someth...
SQL Update with row_number()
...able and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator.
Instead, you could just have given the CTE a different name as well as added the target column to i...
Using two values for one switch case statement
...Days);
}
}
This is the output from the code:
Number of Days = 29
FALLTHROUGH:
Another point of interest is the break statement. Each break statement
terminates the enclosing switch statement. Control flow continues with
the first statement following the switch block. The break state...
Are foreign keys really necessary in a database design?
...grammer to manipulate data in the correct way. Suppose a programmer is actually doing this in the right manner already, then do we really need the concept of foreign keys?
...
Obstructed folders in Subversion
...olution can be to export the working copy (the entire checkout you have locally) to somewhere else.
If you are using tortoisesvn, you get the option to "export un-versioned files", but I think if doing it from the command line it only exports versioned files so you might have a bit of a laborious t...
Clicking a button within a form causes page refresh
...
Nice! It really fetched to my scenario!
– Richard
Sep 24 '15 at 14:39
2
...
How to set DOM element as the first child?
I have element E and I'm appending some elements to it. All of a sudden, I find out that the next element should be the first child of E. What's the trick, how to do it? Method unshift doesn't work because E is an object, not array.
...
Adding a column to an existing table in a Rails migration
...cord::Migration[5.0]
def change
end
end
In that case you have to manually an add_column to change:
class AddEmailToUsers < ActiveRecord::Migration[5.0]
def change
add_column :users, :email, :string
end
end
And then run rake db:migrate
...
JavaScript variable assignments from tuples
...
Javascript 1.7 added destructured assignment which allows you to do essentially what you are after.
function getTuple(){
return ["Bob", 24];
}
var [a, b] = getTuple();
// a === "bob" , b === 24 are both true
...
Apache redirect to another port
...//example.com in ProxyPass and ProxyPassReverse and leave it as /. Additionally, you need to leave the / at the end of example/ to where it is redirecting. Also, I had some trouble with http://example.com vs. http://www.example.com - only the www worked until I made the ServerName www.example.com, a...