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How can you represent inheritance in a database?
I'm thinking about how to represent a complex structure in a SQL Server database.
8 Answers
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PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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Android encryption / decryption using AES [closed]
...se as it is insecure (using SHA1PRNG for key derivation and using AES in ECB mode)
Instead (as of 2016), use PBKDF2WithHmacSHA1 for key derivation and AES in CBC or GCM mode (GCM provides both privacy and integrity)
You could use functions like these:
private static byte[] encrypt(byte[] raw, byte[]...
How does Duff's device work?
...kipedia on the Duff's device , and I don't get it. I am really interested, but I've read the explanation there a couple of times and I still don't get it how the Duff's device works.
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Sprintf equivalent in Java
Printf got added to Java with the 1.5 release but I can't seem to find how to send the output to a string rather than a file (which is what sprintf does in C). Does anyone know how to do this?
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How to find if a native DLL file is compiled as x64 or x86?
I want to determine if a native assembly is complied as x64 or x86 from a managed code application ( C# ).
11 Answers
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How to debug Ruby scripts [closed]
I copied the following Ruby code from the Internet and made a few changes but it doesn't work.
17 Answers
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When do I need to use AtomicBoolean in Java?
How I can use AtomicBoolean and what is that class for?
5 Answers
5
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Synchronization vs Lock
java.util.concurrent API provides a class called as Lock , which would basically serialize the control in order to access the critical resource. It gives method such as park() and unpark() .
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Why does 'continue' behave like 'break' in a Foreach-Object?
...se the return instead of the continue. This return returns from the script block which is invoked by ForEach-Object on a particular iteration, thus, it simulates the continue in a loop.
1..100 | ForEach-Object {
if ($_ % 7 -ne 0 ) { return }
Write-Host "$($_) is a multiple of 7"
}
There i...