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ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
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Set a cookie to never expire
Looking at the php documentation on setting a cookie I see that I can set an expiration date for the cookie. You can set the cookie to expire at the end of the browser session or at some time in the future but I do not see a way to set the cookie to never expire. Is this even possible and how is...
What's a reliable way to make an iOS app crash?
I want to test my app's crash reporting out in the field by deliberately having it crash when the user performs a particular action that a real user is unlikely to do accidentally.
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What is simplest way to read a file into String? [duplicate]
I am trying to read a simple text file into a String. Of course there is the usual way of getting the input stream and iterating with readLine() and reading contents into String.
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What's the difference between git reset --mixed, --soft, and --hard?
I'm looking to split a commit up and not sure which reset option to use.
14 Answers
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Does Foreign Key improve query performance?
Suppose I have 2 tables, Products and ProductCategories. Both tables have relationship on CategoryId. And this is the query.
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Getting a list of files in a directory with a glob
For some crazy reason I can't find a way to get a list of files with a glob for a given directory.
10 Answers
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Abstract functions in Swift Language
I'd like to create an abstract function in swift language. Is it possible?
11 Answers
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Comparing two dictionaries and checking how many (key, value) pairs are equal
I have two dictionaries, but for simplification, I will take these two:
26 Answers
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What is the use of hashCode in Java?
In Java, obj.hashCode() returns some value. What is the use of this hash code in programming?
9 Answers
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