All Questions

2
answers

What is the name of the = operator in PHP used in arrays?

In PHP, when we are going to declare a array directly, we have the => operator. I know that in PHP we have -> , which is object separator , but I needed to give the name to => and could not explain. Wha...
asked on 28.07.2015 / 17:26
2
answers

What is the difference between where and having?

Doing some testing on a database in MySQL, I realized that: SELECT * From client WHERE uuid = '1kvsg4oracxq' returns the same result as: SELECT * From client HAVING uuid = '1kvsg4oracxq' What exactly is the difference between where...
asked on 09.06.2017 / 21:06
3
answers

Why calling System.gc does not guarantee execution of the garbage collector?

Why does not the developer have full control over the garbage collector ? I understand that the role of GC is to automatically manage memory but why even using some method like System.gc is there no guarantee that the GC will run?   ...
asked on 22.12.2015 / 05:23
2
answers

Why use a generic return?

I was looking at the signature class methods Optional and I did not understand what this <T> means in front of the method return empty() : public static <T> Optional<T> empty() It returns a O...
asked on 26.11.2015 / 22:28
4
answers

Select mysql accent showing question mark " " [duplicate]

Today I migrated my site to the hostgator and this problem happened, the accents are all with some characters The files are all with correct accent in the database My collation in the database is like: utf8_general_ci I'm using meta...
asked on 26.04.2014 / 00:23
2
answers

What are schemas? What are the advantages of using it?

In which situations is its use recommended?     
asked on 11.06.2014 / 22:09
1
answer

Map of Brazil - what is the best way to do it?

I have the following map: When the client hovers over a state, it has to change color. I thought of making several divs, to mount the map. Only this will generate a problem, as the divs are square, you will have to move the mouse right in...
asked on 12.03.2015 / 14:46
2
answers

Why is set theory so important for computing?

For the theory of computation, formal languages among other areas as well as for programming (development) set theory is always present, I know that mathematics is strongly linked to computing, but why is there so much emphasis on sets?!     
asked on 31.08.2015 / 04:21
1
answer

How to read binary file content in Javascript

How to read binary file content in Javascript?     
asked on 15.05.2015 / 19:50
3
answers

What technologies can I use to create a PWA

I've already seen What are Progressive Web Apps? and google documentation, but I still have a question: What technologies are available that can be used to create a progressive web application? In addition, of course HTML, CSS and JS. Fo...
asked on 30.04.2018 / 22:10