How to convert date formats in SQLite

Date types are handled like a string in SQLite and below is an example of how to change the date format from MM/dd/yyyy to yyyy-MM-dd. With a little modification it can be used for other formats too.

select substr(column, 7, 4)||”-“||substr(column, 1,2)||”-“||substr(column, 4,2) from table

Shell Overlay Icons Problem Fix

Having many programs with Shell Overlay Icons in Windows will cause some of them to not appear. This is because there is a limit to how many Shell Overlay Icons. (Not sure but I think it’s around 10 icons)

Below is an example of a Shell Overlay Icon.


To overcome this problem you need to run “regedit” and edit the registry entries in the path below:


Just delete any entries you don’t need and restart.

How to limit 32-bit applications to one instance in Visual C++ (with or without Qt)

I use the code from the following article to allow only a single instance of my programs (mostly written using Qt Framework) to run on Windows. Some programs (specially the ones which connect to a specific type of hardware or resource) need this limitation to avoid conflicts.

Please also note that this code is specific to Windows.

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Build Qt-Static using MSVC2010

I keep the following notes (steps) as a personal guideline for building Qt Statically using Microsoft Visual C++ and I never fail to do it but please keep in mind that these are NOT some exact steps and they need to be changed (slightly though 🙂 ) in some cases. Leave comments if you have any questions.

I have used Qt 5.4.0 with Microsoft Visual C++ 2010 (MSVC2010) but it is more or less the same for similar compilers and others Qt versions.

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Required Includes and Libraries for OpenCV in Qt

Update on March 18th, 2018: Now you can use this post for a more recent, accurate and complete guide on adding OpenCV to Qt projects.

Use the following lines in a .pri file that is added to your project by using “include(C:/opencv/opencv.pri)”. This allows easy including of headers and library references in a Qt project.

(Note that in case you are using another version of OpenCV, your library names might be different.)

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