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Is there ever a time where using a database 1:1 relationship makes sense?
I was thinking the other day on normalization, and it occurred to me, I cannot think of a time where there should be a 1:1 relationship in a database.
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How to drop into REPL (Read, Eval, Print, Loop) from Python code
Is there a way to programmatically force a Python script to drop into a REPL at an arbitrary point in its execution, even if the script was launched from the command line?
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How to count occurrences of a column value efficiently in SQL?
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This should work:
SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) as cnt
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Creating an official github mirror
How do I create a github mirror for an external git repository, such that it appears as "real mirror", e.g., as in https://github.com/mirrors ?
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How to see full symlink path
When I'm using ls -la symlinkName or stat symlinkName not all the path is displayed
(e.g ../../../one/two/file.txt )
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Showing a Spring transaction in log
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in your log4j.properties (for alternative loggers, or log4j's xml format, check the docs)
Depending on your transaction manager, you can set the logging level of the spring framework so that it gives you more info about transactions. For example, in case of using JpaTransactionManager, ...
What is the difference between gmake and make?
I am trying to understand the difference between 'gmake' and 'make'?
4 Answers
4
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When does static class initialization happen?
... but I access a static field, are ALL the static blocks and private static methods used to instantiate private static fields called (in order) at that instant?
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Django in / not in query
I'm trying to figure out how to write a 'not in' style query in django.
For example, the query structure I'm thinking of would look like this.
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What is the maximum depth of the java call stack?
...nto the call stack before I get a StackOverflowError? Is the answer platform dependent?
4 Answers
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