SUSE Hack Week: Learn & Improve Qt, C++

# A First Level Header
## A Second Level Header

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This is an [link to example.com](http://example.com/)

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This is a user link @hans

This is a project link hw#some-cool-title

My hack week started in a funny fashion, while it was almost 40C degree 
outside the postal service rang the bell. I had no idea what it was since I 
was not expecting anything, so I went down and picked it, it was a box from 
Provo weighting almost 1kg , so I assumed 'cool, my hackweek t-shirt! and 
maybe something else..' I opened the box and a huge coat with cap which 
probably would melt me, fortunately we will exit summer eventually and get 
colder days, on which I can use my new coat.

My project was:
Learn & Improve Qt, C++ - Project Oficina -> https://hackweek.suse.com/15/
projects/learn-and-improve-qt-c-plus-plus-project-oficina

Code -> https://github.com/bedi1982/Oficina

This code I learned by myself, reading man pages and googling all around, so 
in my mind I was pretty sure that there is bad implemented stuff, so the 
initial idea was to 'improve/refactor' existing code and while doing this 
maybe get some new ideas. And it worked very well, at least the shittiest 
functions I was able to refactor and make work/look decently, and I will 
explain just this one,  as it was a good achievement in my point of view:

On Qt on a line edit(line edit is a line on which the user enters text, like 
where you enter text in the web browser), on this line you can 'assign' 
commands on user 'actions', for example, in my case when one single letter 
changed on the 'line edit' an underlying function was called, what this 
function did?

It created a data model  with all the results from a SQL query, for each 
letter the user entered it opened a SQL query and recreated that model, 
let's use as example the word 'suse'.

So, let's say the user is inserting the word suse, so first letter:

s
underlying function would call: 
select distro_names from distro where distro_name starts with %s%;

u
underlying function would call: 
select distro_names from distro where distro_name starts with %u%;

s
underlying function would call: 
select distro_names from distro where distro_name starts with %s%;

e
underlying function would call: 
select distro_names from distro where distro_name starts with %e%;

This was totally insane, 4 queries for 4 letters, and a backspace would 
generate even more queries.

So I researched the correct way, and the correct way is to create a proxy of 
the model:

Funtion model-generator{
//Regular model:
        model = new QSqlTableModel();
        model->setTable("Client");
        model->select();

//NEW
++//Proxy of the model:
++       proxy = new QSortFilterProxyModel();
++       proxy->setSourceModel(model);

//put the proxy on the interface:
++        ui->tbl_Client_List->setModel(proxy);
}

So now all 'search' operations will be done on the proxy, not the model.

At some points the model has to be 'regenerated' to include new data, but this 
is very simple, just need to call 'Function model-generator', which is fixed 
one query always.

My hack week started in a funny fashion, while it was almost 40C degree outside the postal service rang the bell. I had no idea what it was since I was not expecting anything, so I went down and picked it, it was a box from Provo weighting almost 1kg , so I assumed 'cool, my hackweek t-shirt! and maybe something else..' I opened the box and a huge coat with cap which probably would melt me, fortunately we will exit summer eventually and get colder days, on which I can use my new coat.

My project was: Learn & Improve Qt, C++ - Project Oficina -> https://hackweek.suse.com/15/ projects/learn-and-improve-qt-c-plus-plus-project-oficina

Code -> https://github.com/bedi1982/Oficina

This code I learned by myself, reading man pages and googling all around, so in my mind I was pretty sure that there is bad implemented stuff, so the initial idea was to 'improve/refactor' existing code and while doing this maybe get some new ideas. And it worked very well, at least the shittiest functions I was able to refactor and make work/look decently, and I will explain just this one, as it was a good achievement in my point of view:

On Qt on a line edit(line edit is a line on which the user enters text, like where you enter text in the web browser), on this line you can 'assign' commands on user 'actions', for example, in my case when one single letter changed on the 'line edit' an underlying function was called, what this function did?

It created a data model with all the results from a SQL query, for each letter the user entered it opened a SQL query and recreated that model, let's use as example the word 'suse'.

So, let's say the user is inserting the word suse, so first letter:

s underlying function would call: select distronames from distro where distroname starts with %s%;

u underlying function would call: select distronames from distro where distroname starts with %u%;

s underlying function would call: select distronames from distro where distroname starts with %s%;

e underlying function would call: select distronames from distro where distroname starts with %e%;

This was totally insane, 4 queries for 4 letters, and a backspace would generate even more queries.

So I researched the correct way, and the correct way is to create a proxy of the model:

Funtion model-generator{ //Regular model: model = new QSqlTableModel(); model->setTable("Client"); model->select();

//NEW ++//Proxy of the model: ++ proxy = new QSortFilterProxyModel(); ++ proxy->setSourceModel(model);

//put the proxy on the interface: ++ ui->tblClientList->setModel(proxy); }

So now all 'search' operations will be done on the proxy, not the model.

At some points the model has to be 'regenerated' to include new data, but this is very simple, just need to call 'Function model-generator', which is fixed one query always.

# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

- Use hyphens
- for unordereed
- lists

This is an [link to example.com](http://example.com/)

This is an image ![an openSUSE geeko icon](https://en.opensuse.org/images/d/d0/Icon-distribution.png)

This is a user link @hans

This is a project link hw#some-cool-title

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