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Database development mistakes made by application developers [closed]
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1. Not using appropriate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the queries you nee...
How to check if an object is nullable?
...ullable - Nullable<T> and reference-type.
Jon has corrected me that it is hard to get type if boxed, but you can with generics:
- so how about below. This is actually testing type T, but using the obj parameter purely for generic type inference (to make it easy to call) - it would work almos...
Is it possible to Turn page programmatically in UIPageViewController?
Is it possible to turn page programmatically in UIPageViewController ?
17 Answers
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Is Java a Compiled or an Interpreted programming language ?
...the past I have used C++ as a programming language. I know that the code written in C++ goes through a compilation process until it becomes object code "machine code".
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Why can templates only be implemented in the header file?
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Caveat: It is not necessary to put the implementation in the header file, see the alternative solution at the end of this answer.
Anyway, the reason your code is failing is that, when instantiating a template, the compiler creates a...
What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?
... the client is the browser and the server is the webserver hosting the website.
Before you can understand these technologies, you have to understand classic HTTP web traffic first.
Regular HTTP:
A client requests a webpage from a server.
The server calculates the response
The server sends the re...
How can I round a number in JavaScript? .toFixed() returns a string?
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It returns a string because 0.1, and powers thereof (which are used to display decimal fractions), are not representable (at least not with full accuracy) in binary floating-point systems.
For example, 0.1 is really 0.100000...
Mod of negative number is melting my brain
I'm trying to mod an integer to get an array position so that it will loop round. Doing i %
arrayLength works fine for positive numbers but for negative numbers it all goes wrong.
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Why are only a few video games written in Java? [closed]
... aren't many commercial, 3D video games (not random open source 2D ones) written in Java? In theory, it makes a lot of sense: you get a productivity boost and a cross-platform application almost for free, among other things, such as the vast amount of Java libraries, and built-in garbage collection ...
Java: Get first item from a collection
...llection, such as Collection<String> strs , how can I get the first item out? I could just call an Iterator , take its first next() , then throw the Iterator away. Is there a less wasteful way to do it?
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