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Is an index needed for a primary key in SQLite?
...x be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all the time).
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Are there any SHA-256 javascript implementations that are generally considered trustworthy?
...er. I'm having trouble figuring out which SHA-256 implementation I can actually trust. I was expecting there to be some kind of authoritative script that everyone used, but I'm finding loads of different projects all with their own implementations.
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MySQL - Using COUNT(*) in the WHERE clause
...Bother To Teach Properly on sql courses or books and knowing about it generally the sign that the coder has progressed beyond novice level.
– Cruachan
Nov 19 '08 at 12:59
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Dynamically Changing log4j log level
What are the different approaches for changing the log4j log level dynamically, so that I will not have to redeploy the application. Will the changes be permanent in those cases?
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How to install 2 Anacondas (Python 2 and 3) on Mac OS
I'm relatively new in Mac OS. I've just installed XCode (for c++ compiler) and Anaconda with the latest Python 3 (for myself). Now I'm wondering how to install properly second Anaconda (for work) with Python 2?
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Go build: “Cannot find package” (even though GOPATH is set)
...It does not work because your foobar.go source file is not in a directory called foobar. go build and go install try to match directories, not source files.
Set $GOPATH to a valid directory, e.g. export GOPATH="$HOME/go"
Move foobar.go to $GOPATH/src/foobar/foobar.go and building should work just ...
Rails: Why does find(id) raise an exception in rails? [duplicate]
... (1, 5, 6), or an array of ids ([5, 6, 10]). If no record can be found for all of the listed ids, then RecordNotFound will be raised.
If you don't want the exception to be raised, use find_by_id, which will return nil if it can't find an object with the specified id. Your example would then be Us...
PostgreSQL Crosstab Query
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Install the additional module tablefunc once per database, which provides the function crosstab(). Since Postgres 9.1 you can use CREATE EXTENSION for that:
CREATE EXTENSION IF NOT EXISTS tablefunc;
Improved test case
CREATE ...
Jasmine.js comparing arrays
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this falls back on "==" in javascript by default. This is just not safe since not only the actual values are compared, but the whole object.
– Peter
Nov 12 '14 at 11:00
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Javascript roundoff number to nearest 0.5
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rounding the num*2 is not working for all case..try any decimal like 15.27 => using your formula will give => 15 where in fact it should have returned 15.5. **** I think using toFixed will be better (num*2).toFixed()/2
– sfdx bomb
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