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Difference between Key, Primary Key, Unique Key and Index in MySQL
...users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have to go through all the records of the table: this is slow, because the more records you have in your database, the more work it has to do to find the result. On the other hand, a...
Extract traceback info from an exception object
Given an Exception object (of unknown origin) is there way to obtain its traceback? I have code like this:
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nullable object must have a value
...e receiving was thrown in the .Value property of the Nullable DateTime, as it is required to return a DateTime (since that's what the contract for .Value states), but it can't do so because there's no DateTime to return, so it throws an exception.
In general, it is a bad idea to blindly call .Value...
Pure JavaScript equivalent of jQuery's $.ready() - how to call a function when the page/DOM is ready
With jQuery, we all know the wonderful .ready() function:
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How to deploy an ASP.NET Application with zero downtime
To deploy a new version of our website we do the following:
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Java - No enclosing instance of type Foo is accessible
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static class Thing will make your program work.
As it is, you've got Thing as an inner class, which (by definition) is associated with a particular instance of Hello (even if it never uses or refers to it), which means it's an error to say new Thing(); without having a partic...
How to choose an AES encryption mode (CBC ECB CTR OCB CFB)?
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ECB should not be used if encrypting more than one block of data with the same key.
CBC, OFB and CFB are similar, however OFB/CFB is better because you only need encryption and not decryption, which can save code space.
CTR is used if you want good parallelization (ie. speed), instead of CB...
Why not infer template parameter from constructor?
...'t the compiler infer template parameters from class constructors, much as it can do from function parameters? For example, why couldn't the following code be valid:
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How do I restore a dump file from mysqldump?
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It should be as simple as running this:
mysql -u <user> -p < db_backup.dump
If the dump is of a single database you may have to add a line at the top of the file:
USE <database-name-here>;
If it was a du...
Implications of foldr vs. foldl (or foldl')
...am reading, says to never use foldl and instead use foldl' . So I trust it.
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