How to upgrade 2.3.1 to 2.4.3

Hello

How to upgrade Litecart 2.3.1 to 2.4.3 ?

Did you miss the wiki article?
https://wiki.litecart.net/how_to_upgrade

Should I enable them ? if yes How ?

For upgrade I should replace files, if I replace files I changed files is gone, I need to keep these changes while upgrading. How can I do it ?

You should work using custom templates, and ideally not edit Litecart core files, but use vQmod files instead. That way it is easier to prevent losing changes.
If you made a lot of changes I would suggest downloading your installation and use a file compare tool to compare it to the core files. See: https://wiki.litecart.net/how_to_turn_modifications_into_vqmods

@abdumalik You activate php extensions in cpanel under "Select php version". Your webhost should provide instructions for this.

"Intl" is a must with PHP 8.0. Imagick and apcu are recommended but not mandatory.

It's done thanks.

Does database have changes in new version?

I got this error after merged my files into new version files. Look on image!

did jobs_interval remove on new version? if yes, How do I fix this on screenshot?

Are you on 2.4.3 or 2.4.4 now?
Yes jobs_interval has been removed so make sure you run the same version of the files as your litecart database version.

Always run /install/upgrade.php to upgrade.

it is 2.4.3 now

There is no trace of the text "jobs_interval" in any script in 2.4.3. It was removed in 2.4.2. You must have gotten your file versions mixed up. Drop 2.4.3 on top overwriting your existing.

It’s done, thank you for help.

Next problem is how to merge two databases, I mean, moving new tables, columns into next version database like 2.x.x to 3.x.x

[quote]Next problem is how to merge two databases, I mean, moving new tables, columns into next version database like 2.x.x to 3.x.x[/quote]
This is what the upgrade patches do. An upgrade takes 3 min:

1. Upload the files on top of your existing.
2. Run install/upgrade.php
3. Remove the install/ folder.
   What remains are files and database tables conforming with the new version.

To me it sound like you made it way to complicated by installing a new platform then manually copying content from the old to the new.

yes cuz I changed a lot of things in system then I made vqmods now for these changes if I did as you told upgrading it was going to break totally. Now it’s okay just db left.

Thank you

Did you consider the git alternative? That's the option if you want to hardcode your modifications straight in the core files. It let's you pull and merge updates with one command (git pull).
https://wiki.litecart.net/how_to_adapt_to_git

You can see in the upgrade patches what was made to the databases and copy some queries to run manually. Another way is to export an sql structure file and compare it between the two databases what differs. WinMerge is a good tool for comparing two files.

SOLVED!

Thank you for your help Tim.