Update xampp from maria db 10.1 to 10.2

1 : Shutdown or Quit your XAMPP server from Xampp control panel.
2 : Download the ZIP version of MariaDB
3 : Rename the xampp/mysql folder to mysql_old.
4 : Unzip or Extract the contents of the MariaDB ZIP file into your XAMPP folder.
5 : Rename the MariaDB folder, called something like mariadb-5.5.37-win32, to mysql.
6 : Rename xampp/mysql/data to data_old.
7 : Copy the xampp/mysql_old/data folder to xampp/mysql/.
8 : Copy the xampp/mysql_old/backup folder to xampp/mysql/.
9 : Copy the xampp/mysql_old/scripts folder to xampp/mysql/.
10: Copy mysql_uninstallservice.bat and mysql_installservice.bat from xampp/mysql_old/ into xampp/mysql/.
11 : Copy xampp/mysql_old/bin/my.ini into xampp/mysql/bin.
12 : Edit xampp/mysql/bin/my.ini using a text editor like Notepad. Find skip-federated and add a # in front (to the left) of it to comment out the line if it exists. Save and exit the editor.
13 : Start-up XAMPP.
Note If you can't get mysql to start from Xampp control panel. Add this 'skip-grant-tables' statement anywhere in xampp/mysql/bin/my.ini file
14 : Run xampp/mysql/bin/mysql_upgrade.exe.
15 : Shutdown and restart MariaDB (MySQL).
If still mysql is not started then follow below Note steps(!Important)

Note :mysql error log file: c:\xampp\mysql\bin\mysqld.exe: unknown variable 'innodb_additional_mem_pool_size=2M' like please remove or commented this statement in my.ini file in this path xampp/mysql/bin/my.ini file.

Help from this link.

1. Shutdown MySQL in your XAMPP server from Xampp control panel or mysql under Services if it was added.
2. Download the ZIP version of MariaDB (https://downloads.mariadb.org/) - you may download the winx64.zip if you are also switching to x64 variant of mariadb
3. Rename the xampp/mysql folder to mysql_old
4. Unzip or Extract the contents of the MariaDB ZIP file into your XAMPP folder
5. Rename the MariaDB folder, called something like mariadb-10.3.14-winx64, to mysql
6. Rename xampp/mysql/data to data_temp
7. Copy the xampp/mysql_old/data folder to xampp/mysql/
8. Copy the xampp/mysql_old/backup folder to xampp/mysql/
9. Copy the xampp/mysql_old/scripts folder to xampp/mysql/
10. Copy mysql_uninstallservice.bat and mysql_installservice.bat from xampp/mysql_old/ into xampp/mysql/
11. Copy xampp/mysql_old/bin/my.ini into xampp/mysql/bin
12. Edit xampp/mysql/bin/my.ini using a text editor like Notepad

Find skip-federated and add a # in front (to the left) of it to comment out the line if it exists

Find innodb_additional_mem_pool_size=2 and add a # in front (to the left) of it to comment out the line if it exists

Add this skip-grant-tables statement anywhere in xampp/mysql/bin/my.ini file Save and exit the editor

13. Start-up XAMPP
14. Run xampp/mysql/bin/mysqlcheck --repair --all-databases
15. Run xampp/mysql/bin/mysql_upgrade.exe
16. Shutdown and restart MySQL (MariaDB)

prior to running

mysql_upgrade

do this first

mysqlcheck --repair --all-databases

I generally use a simpler method, which is to install a new version of xampp on a separate computer. Then copy the installed mysql folder over and replace the data folder with the previous version.

Then run "C:\xampp\mysql\bin\mysql_upgrade.exe"

Please follow this process

1. Clean shutdown
2. cd C:\xampp\mysql\bin
3. mysqladmin -uroot shutdown
4. cd\
5. Backup mysql
6. rename C:\xampp\mysql to C:\xampp\mysql_10.4
7. extract mariadb-10.8.3-winx64.zip (extract here to prevent duplicate folder)
8. rename mariadb-10.8.3-winx64 to mysql
9. copy mysql folder from zip to C:\xampp\
10. Copy the following from mysql_10.4 to mysql

\bin\my.ini
\backup
\data\
\scripts\
\*.*

11. Start mysql in xampp control panel
12. cd C:\xampp\mysql\bin
13. mysqlcheck -uroot --repair --all-databases
14. mysql_upgrade.exe
15. stop start mysql in xampp