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SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first query to be quicker, mainly because you have an equivalence and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may va...
Git error: src refspec master does not match any [duplicate]
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You've created a new repository and added some files to the index, but you haven't created your first commit yet. After you've done:
git add a_text_file.txt
... do:
git commit -m "Initial commit."
... and those errors should go away.
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Getting started with Haskell
...ional programming paradigm in Haskell. I've done this by reading tutorials and watching screencasts, but nothing really seems to stick.
Now, in learning various imperative/OO languages (like C, Java, PHP), exercises have been a good way for me to go. But since I don't really know what Haskell is cap...
What is the 'dynamic' type in C# 4.0 used for?
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The dynamic keyword is new to C# 4.0, and is used to tell the compiler that a variable's type can change or that it is not known until runtime. Think of it as being able to interact with an Object without having to cast it.
dynamic cust = GetCustomer();
cust.Fir...
Postgres - FATAL: database files are incompatible with server
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If you recently upgraded to 11 or 12 from 10.x you can run the below command to upgrade your postgres data directory retaining all data:
brew postgresql-upgrade-database
The above command is taken from the output of brew info postgres
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How to enter a multi-line command
Is it possible to split a PowerShell command line over multiple lines?
12 Answers
12
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Execute unit tests serially (rather than in parallel)
...gure which services are available without having to bring all of them down and restart them whenever a new service is added or an old one is removed.
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Does use of final keyword in Java improve the performance?
...s, HotSpot keeps track of whether the method has actually been overridden, and is able to perform optimizations such as inlining on the assumption that a method hasn't been overridden - until it loads a class which overrides the method, at which point it can undo (or partially undo) those optimizati...
problem with and :after with CSS in WebKit
...n a select box with the pseudo :after (to style my select box with 2 parts and without images). Here's the HTML:
9 Answers
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How can I get query string values in JavaScript?
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Update: Sep-2018
You can use URLSearchParams which is simple and has decent (but not complete) browser support.
const urlParams = new URLSearchParams(window.location.search);
const myParam = urlParams.get('myParam');
PS
Unfortunately URLSearchParams don't properly parse query strings ...