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PG undefinedtable error relation users does not exist
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At first, you shall detach all connections out of database. By default you use the development environment. Then try to reset database with the following:
rake db:reset
The rake db:reset task will drop the database and set it up again....
How do I add comments to package.json for npm install?
... prevents you from using npm version and other command line utils which usually reparse whole JSON and discard the duplicate keys in process.
– jakub.g
Jul 1 '14 at 11:51
62
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Check if a subview is in a view
...he same way, when the button with that IBAction is touched again should call removeFromSuperview on that subview added on that IBAction :
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How can I wait In Node.js (JavaScript)? l need to pause for a period of time
... console.log('Welcome to My Console,');
}
function function2() {
// all the stuff you want to happen after that pause
console.log('Blah blah blah blah extra-blah');
}
// call the first chunk of code right away
function1();
// call the rest of the code and have it execute after 3 seconds...
What is (functional) reactive programming?
...read the Wikipedia article on reactive programming . I've also read the small article on functional reactive programming . The descriptions are quite abstract.
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Error: The 'brew link' step did not complete successfully
I'm trying to install node.js via Homebrew. Unfortunately, I get this error:
21 Answers
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How to split a string, but also keep the delimiters?
...ve an obvious maximum length" trying to use this with a regex representing all real numbers.
– daveagp
May 28 '14 at 15:00
2
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Vertical Text Direction
... the following property to your css.
white-space: pre;
So, the css class shall be
.vericaltext{
width:1px;
word-wrap: break-word;
font-family: monospace; /* this is just for good looks */
white-space: pre;/* this is for displaying whitespaces */
}
JSFiddle! Demo With Whitespace
Upda...
Hide Utility Class Constructor : Utility classes should not have a public or default constructor
...c final class FilePathHelper {
private FilePathHelper() {
//not called
}
}
This prevents the default parameter-less constructor from being used elsewhere in your code. Additionally, you can make the class final, so that it can't be extended in subclasses, which is a best practice for ...
Cleanest way to build an SQL string in Java
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First of all consider using query parameters in prepared statements:
PreparedStatement stm = c.prepareStatement("UPDATE user_table SET name=? WHERE id=?");
stm.setString(1, "the name");
stm.setInt(2, 345);
stm.executeUpdate();
The ...