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Specifying an Index (Non-Unique Key) Using JPA
...ng JPA annotations. We need a non-unique key on email because there are literally millions of queries on this field per day, and its a bit slow without the key.
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How do I use installed packages in PyCharm?
...+ button in the Paths area. You can put the path to the module you'd like it to recognize.
But I don't know the path..
Open the python interpreter where you can import the module.
>> import gnuradio
>> gnuradio.__file__
"path/to/gnuradio"
Most commonly you'll have a folder structu...
What should my Objective-C singleton look like? [closed]
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Another option is to use the +(void)initialize method. From the documentation:
The runtime sends initialize to each class in a program exactly one time just before the class, or any class that inherits from it, is sent its first message from within the progr...
MySQL check if a table exists without throwing an exception
... best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
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Python loop that also accesses previous and next values
How can I iterate over a list of objects, accessing the previous, current, and next items? Like this C/C++ code, in Python?
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Why does changing 0.1f to 0 slow down performance by 10x?
Why does this bit of code,
5 Answers
5
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How to efficiently count the number of keys/properties of an object in JavaScript?
...at's the fastest way to count the number of keys/properties of an object? It it possible to do this without iterating over the object? i.e. without doing
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Python Script execute commands in Terminal
I read this somewhere a while ago but cant seem to find it. I am trying to find a command that will execute commands in the terminal and then output the result.
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Iterating over each line of ls -l output
I want to iterate over each line in the output of: ls -l /some/dir/*
6 Answers
6
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ERROR:'keytool' is not recognized as an internal or external command, operable program or batch file
...n your %PATH% environment variable.
For example, on my Windows 7 machine, it is in
C:\Program Files (x86)\Java\jre6\bin, and my %PATH% variable looks like C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\Program Files (x86)\Java\jre6\bin;C:\WINDOWS\System32\WindowsPowerShell\v1.0\ (and ...