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Operator overloading : member function vs. non-member function?
I read that an overloaded operator declared as member function is asymmetric because it can have only one parameter and the other parameter passed automatically is the this pointer. So no standard exists to compare them. On the other hand, overloaded operator declared as a friend is symmetric...
Preserve line endings
I run sed to do some substitution on windows and I noticed that it automatically converts line endings to Unix (\n). Is there an option to tell sed to use Windows line endings (\r\n) or even better to preserve the line endings from the file?
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WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
Could someone give me some guidance on when I should use WITH (NOLOCK) as opposed to SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
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How do I automatically update a timestamp in PostgreSQL
I want the code to be able to automatically update the time stamp when a new row is inserted as I can do in MySQL using CURRENT_TIMESTAMP.
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What is this CSS selector? [class*=“span”]
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It's an attribute wildcard selector. In the sample you've given, it looks for any child element under .show-grid that has a class that CONTAINS span.
So would select the <strong> element in this example:
<div class="show-grid"&g...
Alter column, add default constraint
I have a table and one of the columns is "Date" of type datetime. We decided to add a default constraint to that column
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How to do error logging in CodeIgniter (PHP)
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CodeIgniter has some error logging functions built in.
Make your /application/logs folder writable
In /application/config/config.php set $config['log_threshold'] = 1; or use a higher number, depending on how much detail you want in your logs
Use log_message(...
Change a column type from Date to DateTime during ROR migration
I need to change my column type from date to datetime for an app I am making. I don't care about the data as its still being developed.
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How should I escape commas and speech marks in CSV files so they work in Excel?
I'm generating a CSV file (delimited by commas rather than tabs). My users will most likely open the CSV file in Excel by double clicking it. My data may contain commas and speech marks, so I'm escaping those as follows.
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How to generate an openSSL key using a passphrase from the command line?
First - what happens if I don't give a passphrase? Is some sort of pseudo random phrase used? I'm just looking for something "good enough" to keep casual hackers at bay.
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