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How unique is UUID?
...ify something (I'm using it for files uploaded to the server)? As I understand it, it is based off random numbers. However, it seems to me that given enough time, it would eventually repeat it self, just by pure chance. Is there a better system or a pattern of some type to alleviate this issue?
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Insert, on duplicate update in PostgreSQL?
...mple 38-2. Exceptions with UPDATE/INSERT
This example uses exception handling to perform either UPDATE or INSERT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key...
iPhone app signing: A valid signing identity matching this profile could not be found in your keycha
...r every invalid provisioning profile have a button "Renew". After renewing and downloading updated provisioning profile all seems to work as expected, so problem is definitely solved :)
Update: you may have to contact Apple to get a "Renew"-button, or they removed it -- and the solution is to just ...
Printing everything except the first field with awk
...1 = ""; print $0, first; }'
You can also find the number of columns in NF and use that in a loop.
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iOS Simulator failed to install the application
...oblem
Deleting contents of ~/Library/Application Support/iPhone Simulator and re-run the project solved this problem.
or you can simply reset content and setting of the simulator.
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Stateless and Stateful Enterprise Java Beans
I am going through the Java EE 6 tutorial and I am trying to understand the difference between stateless and stateful session beans. If stateless session beans do not retain their state in between method calls, why is my program acting the way it is?
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Pipe output and capture exit status in Bash
I want to execute a long running command in Bash, and both capture its exit status, and tee its output.
15 Answers
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Why do I have to access template base class members through the this pointer?
... deferred until the parameter is known. It's called two-phase compilation, and MSVC doesn't do it but it's required by the standard and implemented by the other major compilers. If you like, the compiler must compile the template as soon as it sees it (to some kind of internal parse tree representat...
Extract a regular expression match
... wraps all the existing regular expression operates in a consistent syntax and adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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Can I use git diff on untracked files?
...diff output, or is my best bet to use git add on the newly created files and the existing files I have edited, then use:
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