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Case in Select Statement
I have an SQL statement that has a CASE from SELECT and I just can't get it right. Can you guys show me an example of CASE where the cases are the conditions and the results are from the cases. For example:
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Accessing the web page's HTTP Headers in JavaScript
...o read the current headers. You could make another request to the same URL and read its headers, but there is no guarantee that the headers are exactly equal to the current.
Use the following JavaScript code to get all the HTTP headers by performing a get request:
var req = new XMLHttpRequest();...
Difference between window.location.assign() and window.location.replace()
What is the difference between window.location.assign() and window.location.replace() , when both redirect to a new page?
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com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
...tions.
DB server has run out of connections.
Something in between Java and DB is blocking connections, e.g. a firewall or proxy.
To solve the one or the other, follow the following advices:
Verify and test them with ping.
Refresh DNS or use IP address in JDBC URL instead.
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How to avoid “RuntimeError: dictionary changed size during iteration” error?
...n you want to delete an object in inner dict. for example you have a dic A and dict B in dict A. if you want to delete object in dict B it occurs error
– Ali-T
Apr 18 at 6:35
1
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What is the purpose of std::make_pair vs the constructor of std::pair?
...hink you can do one = {10, 20} nowadays but I don't have a C++11 compiler handy to check it.
– MSalters
Feb 14 '12 at 8:11
6
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Ruby Arrays: select(), collect(), and map()
..., but a Hash. You can also use select here, but the block is given the key and value in this case:
irb(main):001:0> h = {:sku=>"507772-B21", :desc=>"HP 1TB 3G SATA 7.2K RPM LFF (3 .", :qty=>"", :qty2=>"1", :price=>"5,204.34 P"}
irb(main):002:0> h.select { |key, value| !value.em...
Cython: “fatal error: numpy/arrayobject.h: No such file or directory”
... You don't need to create a setup.py ... you don't need to even open a command line if you use IPython ... it's all very convenient. In your case, try running these commands in IPython or in a normal Python script:
import numpy
import pyximport
pyximport.install(setup_args={"script_args":["--compil...
Using CookieContainer with WebClient class
I've previously used a CookieContainer with HttpWebRequest and HttpWebResponse sessions, but now, I want to use it with a WebClient. As far as I understand, there is no built-in method like there is for HttpWebRequests ( request.CookieContainer ). How can I collect cookies from a WebClient in a Coo...
Why do I get an UnsupportedOperationException when trying to remove an element from a List?
...|")
On better algorithm
Instead of calling remove one at a time with random indices, it's better to generate enough random numbers in the range, and then traversing the List once with a listIterator(), calling remove() at appropriate indices. There are questions on stackoverflow on how to gener...