@jalal_ba you're using OpenCV 3.4 and the guide you referred is using OpenCV 3.2 could it be possible you try with the old version to see what happens?
In addition, the error you have is related to Google protobuf, so you may want to check this issue regarding OpenCV and protobuf under Windows.
To achieve a single executable that "just runs" on Windows you usually statically link your app and add any needed resources (images, scripts etc.) using the resource system. No special app is needed for that.
That's the standard way to do it. It's the easiest, the fastest and makes least problems to the user.
If you can't do that for any reason you can also create a self extracting archive using one of the popular packers, e.g. 7zip (example here).
When the user specifies his password, hash it and stored the hashed to the database.
When a user tries to logon and specifies a proposed password, hash that and pass it to query like you have to see if it is same as a hash in the database row.
So you never pass the unhashed/clear text of the password to/from the database.
It's OK to be French! Sorry, I had no idea this is what you were wanting!
So you're not avoiding "an empty row", what you're avoiding is "0 rows returned". Your solution will then return 2 rows when there is indeed a matching row to return, and then you use a second LIMIT to eliminate the extra row.
Further, the first part of your query returns a row with 3 columns, while the "unioned" row specifies just one column. Slightly surprised SQL allows this: would have thought you would need SELECT 100, NULL, NULL. But if it works for you that's fine.
Yes indeed, well done! Here instead of trying to use column as a direct JS property reference now you are using [column] as a property accessor and passing the string "trip_time" as the name of the property. In JS object.property refers to the same as object["property"].
thanks a lot for all the answers i've got here. you are really helpful people. i was just wondering if i may come back with questions to ask you in case i would have some? thanks!
No worries you are certainly still welcome in the forum.
Sometimes it is not clear for a user where the actual problem is and they seek advice with the wrong focus on "blaming" Qt.
Therefore, you may still come back with questions related to Qt and also when you are not sure, if it is a Qt problem.
Don't be personally offended when someone pushes back the answer that this is not a Qt related. For most of us English is not the mother language and sometimes you can see also some cultural differences. This may result is some harsh tone.