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Deleting queues in RabbitMQ
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121
If you do not care about the data in management database; i.e. users, vhosts, messages etc., an...
What is the Invariant Culture?
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132
The invariant culture is a special culture which is useful because it will not change. The curre...
select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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What are the differences between Rust's `String` and `str`?
... one can only handle it behind a pointer. This means that str most commonly2 appears as &str: a reference to some UTF-8 data, normally called a "string slice" or just a "slice". A slice is just a view onto some data, and that data can be anywhere, e.g.
In static storage: a string literal "foo" ...
Java Security: Illegal key size or default parameters?
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727
Most likely you don't have the unlimited strength file installed now.
You may need to download...
How do we control web page caching, across all browsers?
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Should Javadoc comments be added to the implementation?
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edited Apr 22 '16 at 10:14
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answered Jun 17 '10 at 14:43
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/bin/sh: pushd: not found
...anged by child processes. (A hypothetical pushd command might do the chdir(2) call and then start a new shell, but ... it wouldn't be very usable.) pushd is a shell builtin, just like cd.
So, either change your script to start with #!/bin/bash or store the current working directory in a variable, d...
Git/GitHub can't push to master
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244
GitHub doesn't support pushing over the Git protocol, which is indicated by your use of the UR...
Drop unused factor levels in a subsetted data frame
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429
All you should have to do is to apply factor() to your variable again after subsetting:
> s...