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Unable to cast object of type 'System.DBNull' to type 'System.String`
...mber.ToString()
EDIT: Haven't paid attention to ExecuteScalar. It does really return null if the field is absent in the return result. So use instead:
return (accountNumber == null) ? string.Empty : accountNumber.ToString()
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Import .bak file to a database in SQL server
...e a charm. These are excellent simplified instructions, and they're essentially the same instructions from the official Microsoft link noted in the most voted up answer here.
– Leonardo Lopez
Jun 4 '15 at 15:50
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Fragments onResume from back stack
...ble to the user) after poping out of the backstack, I'd like some kind of callback to be activated within the fragment (to perform certain changes on a shared UI resource, for instance).
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What is the easiest way to make a C++ program crash?
...I want to make a quick C++ program that crashes on purpose but I don't actually know the best and shortest way to do that, does anyone know what to put between my:
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Run PostgreSQL queries from the command line
... assuming that you have not finished entering your query. This can lead to all kinds of confusion. For example, if you re-enter the same query you will have most likely create a syntax error.
As an experiment, try typing any garble you want at the psql prompt then hit enter. psql will silently prov...
What is the “continue” keyword and how does it work in Java?
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Generally, I see continue (and break) as a warning that the code might use some refactoring, especially if the while or for loop declaration isn't immediately in sight. The same is true for return in the middle of a method, but fo...
Why is a C++ Vector called a Vector?
The question's pretty self-explanatory really. I know vaguely about vectors in maths, but I don't really see the link to C++ vectors.
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How to change folder with git bash?
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Go to the directory manually and do right click → Select 'Git bash' option.
Git bash terminal automatically opens with the intended directory. For example, go to your project folder. While in the folder, right click and select the option and 'Git...
Show constraints on tables command
...QL statement necessary to receate mytable in its current form. You can see all the columns and their types (like DESC) but it also shows you constraint information (and table type, charset, etc.).
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How to clear the cache of nginx?
...f you did, however, then according to the author of nginx, simply removing all files from the cache directory is enough.
Simplest way: find /path/to/your/cache -type f -delete
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