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Java's L number (long) specification
It appears that when you type in a number in Java, the compiler automatically reads it as an integer, which is why when you type in (long) 6000000000 (not in integer's range) it will complain that 6000000000 is not an integer. To correct this, I had to specify 6000000000L . I just learned abo...
SQL JOIN vs IN performance?
...here using a JOIN or an IN will give me the correct results... Which typically has better performance and why? How much does it depend on what database server you are running? (FYI I am using MSSQL)
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How does collections.defaultdict work?
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Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
How to write PNG image to string with the PIL?
...ormat parameter, otherwise PIL will raise an error when trying to automatically detect it.
If you loaded the image from a file it has a format parameter that contains the original file format, so in this case you can use format=image.format.
In old Python 2 versions before introduction of the io m...
Rspec: “array.should == another_array” but without concern for order
...n acceptable answer, is it? Quote from the docs: Passes if actual contains all of the expected regardless of order..
– Joshua Muheim
Jan 22 '13 at 15:44
16
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How can I cast int to enum?
... (e.g. "2342342" -- assuming that's not a value of your enum), it will actually allow that without throwing an error! Your enum will have that value (2342342) even though it's not a valid choice in the enum itself.
– JoeCool
Jun 25 '13 at 15:14
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Copying files from Docker container to host
...ncies on a Continuous Integration (CI) server, so that I don't have to install all the runtimes and libraries on the agents themselves.
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Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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How to reset db in Django? I get a command 'reset' not found error
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It looks like the 'flush' answer will work for some, but not all cases. I needed not just to flush the values in the database, but to recreate the tables properly. I'm not using migrations yet (early days) so I really needed to drop all the tables.
Two ways I've found to drop all ...
How to debug heap corruption errors?
...nctionality was in Application Verifier.
Electric Fence (aka "efence"), dmalloc, valgrind, and so forth are all worth mentioning, but most of these are much easier to get running under *nix than Windows. Valgrind is ridiculously flexible: I've debugged large server software with many heap issues u...