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How to drop a table if it exists?
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Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent tabl...
How to add Options Menu to Fragment in Android
I am trying to add an item to the options menu from a group of fragments.
20 Answers
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Equivalent of .try() for a hash to avoid “undefined method” errors on nil? [duplicate]
In Rails we can do the following in case a value doesn't exist to avoid an error:
12 Answers
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Accessing members of items in a JSONArray with Java
I'm just getting started with using json with java. I'm not sure how to access string values within a JSONArray. For instance, my json looks like this:
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How do I specify unique constraint for multiple columns in MySQL?
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ALTER TABLE `votes` ADD UNIQUE `unique_index`(`user`, `email`, `address`);
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IBOutlet and IBAction
What is the purpose of using IBOutlets and IBActions in Xcode and Interface Builder?
10 Answers
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Android - get children inside a View?
Given a View how can I get the child views inside it?
8 Answers
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How do I add a foreign key to an existing SQLite table?
I have the following table:
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CSS – why doesn’t percentage height work? [duplicate]
...ock element defaults to the height of the block's content. So, given something like this:
<div id="outer">
<div id="inner">
<p>Where is pancakes house?</p>
</div>
</div>
#inner will grow to be tall enough to contain the paragraph and #outer will...
Get value of c# dynamic property via string
I'd like to access the value of a dynamic c# property with a string:
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