All Questions

3
answers

How does serial communication work and how to do it using C / C ++?

I use Debian 7.1 and I need to do serial communication between a computer and a microcontroller using C / C ++ . I have already done a lot of research on the subject, but the articles and examples I found are very confusing, unclear and not v...
asked on 20.03.2014 / 17:05
2
answers

How to set the password for PostgreSQL administration?

I installed PostgreSQL on my Ubuntu using "apt-get". I've been using "sudo" to perform operations (actually following a tutorial), but now I want to administer the DBMS with a client that asks me for the admin password "postgres". How do I se...
asked on 14.12.2013 / 14:36
1
answer

What is using namespace?

Since the beginning of my C ++ learning, I've been told to use namespace std , so I do not spend all the time using std::cout . However, after studying more about language, I learned that :: is a scope operator, but what ab...
asked on 05.12.2018 / 15:38
1
answer

Select rows randomly

I'm developing a very complex system, where in some cases I need to select only a few fields, a friend who has more experience in the area gave me some tips, but he did not explain why. I have the following query that searches all users in r...
asked on 07.12.2017 / 03:56
2
answers

How to redirect from non-www to www?

I want visitors to my site to always access with www . I want to somehow redirect in case the user tries to log in without www or subdomain. If you try to access exemplo.com I want to redirect to www.exemplo.com ....
asked on 11.12.2013 / 23:17
2
answers

Turn columns into rows

I have the following structure: link CREATE TABLE Viagem ( Idasemvolta int, Idacomvolta int ); INSERT INTO Viagem VALUES (64, 39) With the following select: select Idasemvolta, Idacomvolta from viagem This is not the complete st...
asked on 03.10.2018 / 15:47
2
answers

How to deal with ready-made frameworks and technologies? [closed]

I've been having a question a while ago and I think it may even be a common question. I'm not sure how to put the question, but I'll try. When I started programming I dealt with languages like PHP, C, C ++. What I used most in practice was PHP....
asked on 08.05.2014 / 16:53
3
answers

Does the File (String) constructor create a file?

When we use the constructor File f = new File(aquiVemOEnderecoDoArquivo) method, if the file does not exist, is it created?     
asked on 04.12.2018 / 14:04
2
answers

How to create a Grouped List in Laravel 4 from an entity with self-relationship

I'm trying to create a select box com \Form::select() (grouped list) in Laravel 4 and I have the following entity: Items id = id do item nome = nome do item pai = fk dessa mesma entidade I have already created the model with hasMa...
asked on 12.12.2013 / 12:06
2
answers

Infinite scrolling in one page with static data

I have the following structure and want to limit the amount of "class / posts" to display. I want to create a button so that, when clicking, it displays and goes showing more and more "class / posts". I only found tutorials that explain how to d...
asked on 28.08.2018 / 21:52