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Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...ough typeof somewhat confusingly returns object for Null and function for callable Objects, Null is actually not an Object and strictly speaking, in specification-conforming Javascript implementations all functions are considered to be Objects.
That's right - Javascript has no primitive arrays as su...
SQLite UPSERT / UPDATE OR INSERT
...answer. Starting from SQLIte 3.24.0, released on June 4, 2018, there is finally a support for UPSERT clause following PostgreSQL syntax.
INSERT INTO players (user_name, age)
VALUES('steven', 32)
ON CONFLICT(user_name)
DO UPDATE SET age=excluded.age;
Note: For those having to use a vers...
Use jQuery to hide a DIV when the user clicks outside of it
...t with a minor adjustment, using an array of elements to loop through them all at once. jsfiddle.net/LCB5W
– Thomas
Dec 23 '13 at 21:56
5
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How to solve “Plugin execution not covered by lifecycle configuration” for Spring Data Maven Builds
..., in order to avoid the exceptions in Eclipse, one needs to simply enclose all the plugin tags inside a <pluginManagement> tag, like so:
<build>
<pluginManagement>
<plugins>
<plugin> ... </plugin>
<plugin> ... </plugin...
Difference Between Schema / Database in MySQL
...
As defined in the MySQL Glossary:
In MySQL, physically, a schema is synonymous with a database. You can substitute the keyword SCHEMA instead of DATABASE in MySQL SQL syntax, for example using CREATE SCHEMA instead of CREATE DATABASE.
Some other database products draw a...
How line ending conversions work with git core.autocrlf between different operating systems
...rojects has been making my life miserable for a long time. The problems usually arise when there are already files with different and mixed EOLs already in the repo. This means that:
The repo may have different files with different EOLs
Some files in the repo may have mixed EOL, e.g. a combination...
How do I format a number with commas in T-SQL?
.../index space ratios of some tables in my database. Of course I am getting all sorts of large numbers in the results and my eyes are starting to gloss over. It would be really convenient if I could format all those numbers with commas (987654321 becomes 987,654,321). Funny that in all the many yea...
Javascript when to use prototypes
...ods, over and over.
Instead, those methods are defined on a prototype and all jQuery objects "inherit" that prototype so as to gain all those methods at very little runtime cost.
One vitally important part of how jQuery gets it right is that this is hidden from the programmer. It's treated purely ...
Maven and adding JARs to system scope
...ption) specify the proper repository (if one exists) so it can be automatically downloaded by maven
In either case, remove the <systemPath> tag from the dependency
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What does 'synchronized' mean?
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The synchronized keyword is all about different threads reading and writing to the same variables, objects and resources. This is not a trivial topic in Java, but here is a quote from Sun:
synchronized methods enable a simple
strategy for prevent...