Avoid updating and migrating just content... is it possible?

[gabriel3]

I'm having a lot of trouble trying to update a site from 2.5.28 to 3.5.1
I made various attempts, following slightly different guides, to no avail. I always get the same error.

It is also a site with very few third-party extensions (Akeeba, gk_News, a custom template and HD-OG).
Nonetheless, the update fails every time, giving me an unusable website.

So I thought: maybe I can export the tables related to articles, images, banners (the site is a news portal), install a fresh Joomla 3 on the server, and then populate the db manually?

Can it work, or is it a insane idea?

In case, which tables should I export? Should I make changes to their structure to make them compatible with J3?

[gws]

See if any of these will help you. https://extensions.joomla.org/category/ ... onversion/

[gabriel3]

I was just searching if some extension that does what I need exists. Thank you!

[Webdongle]

A method that works (best done on localhost).

1. Uninstall all non compatible 3rd party extensions
2. In a separate folder install Joomla (of the same version) to a new database
3. Edit the configuration.php of the new install to connect to the original database
4. Disable the 'remember me' plugin and update Joomla
   That will use the fresh files to update the original database
5. In another folder install the latest Joomla (to another database)
6. Install the latest versions of your 3rd party extensions into that install
   That gives you all the fresh files
   Next
7. Connect the configuration.php of that install to you original (updated) database
   You now have your updated site with fresh files

That method works.
#1, #2, #3 and #4 uses fresh files to update your database
#5 and #6 creates fresh files (some 2.x/3.x compatible 3rd party extensions use different file depending on the version of Joomla they are installed into
#7 connects the fresh files to the updated database

If it doesn't work for you then either you are not doing it correctly or your database is corrupt

[gabriel3]

A method that works (best done on localhost).

1. Uninstall all non compatible 3rd party extensions
2. In a separate folder install Joomla (of the same version) to a new database
3. Edit the configuration.php of the new install to connect to the original database
4. Disable the 'remember me' plugin and update Joomla
   That will use the fresh files to update the original database
5. In another folder install the latest Joomla (to another database)
6. Install the latest versions of your 3rd party extensions into that install
   That gives you all the fresh files
   Next
7. Connect the configuration.php of that install to you original (updated) database
   You now have your updated site with fresh files

Thanks.
...but this metod wouldn't generate a Joomla 3 website that tries to use a J2.5 not-updated db?
Wouldn't this be incompatible?

[Webdongle]

Yes it does
You install Joomla 2.5 (same versions as yours)
Then you edit the the configuration.php to connect to your database.
When you log in the new files are connected to your database
You then update and your database using the fresh Joomla files(that are not corrupted by 3rd party extensions.
You have your database updated to 3.9.6

Then you recreate the 3rd party files by installing the latest Joomla (in another folder to another database).
Install the 3rd party extensions
That gives you up to date (3.9.6) Joomla and 3rd party files

You then edit the configuration.php (of the up to date files) to connect to your updated database
Now you have up to date (3.9.6) Joomla and 3rd party files connected to your original data (in a 3.9.6 database

[Webdongle]

3 folders 3 databases (finally 1 of each is used. )

Folder A ... your site files
Folder B ... fresh Joomla same version as yours
Folder C ... latest Joomla

Database A ... your database
Database A ... Joomla database same version as yours
Database A ... latest Joomla database

Files folder B connected to Database A... you update your database
Joomla in Folder C has new 3rd party extensions installed in it ... this recreates your 3rd party files
Files in Folder C connected to Database A ... has 3.6.9 files connected to your NOW UPDATED Database A

[gabriel3]

I'm trying this right now, so I'll see myself if this actually works.
In the meantime, thanks for helping

[Webdongle]

Don't forget to make a backup. It does work. If it fails then you missed a step or your database is corrupted.

It's a bit like the shell game ... keep an eye on the pea

Best done with Wamp on localhost ... you can swap php on the fly.

It updates well

[gabriel3]

Yes, I've made a backup of both files and db at each step

I'm currently at the last steps: install a fresh 3.9 and redirect to the db with data.
If this would even fail I currently have a working 3.9 updated all the way from 2.5 in a subfolder.

You made my day, thank you!

Then I'll have to install a new template and re-assign all the modules in the new template

[Webdongle]

The reason it works:
Your database is your site all the files do is put/get data to/from the database and display it in the browser.
By installing a Joomla (of the same version) and connecting the files to the original database ... you allow the update to work with Joomla files only (without 3rd party files interfering).
Installing a fresh Joomla and installing 3rd party extensions creates the up to date files to put/get files to/from your updated database.

Once you do it successfully the first time it becomes easy. It is also great for rebuilding a site if you need to delete files of a hacked site. You only need to install a fresh Joomla once and the 3rd party extensions in to it if you are rebuilding (not updating).