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.

I tried the same solution did not work for me check the error log and based on this i commented out this option because it has been deprecated.

Line number 145 in my.ini file#innodb_additional_mem_pool_size = 2M2018-02-17 23:08:47 bf0 InnoDB: Warning: Using innodb_additional_mem_pool_size is DEPRECATED. This option may be removed in future releases, together with the option innodb_use_sys_malloc and with the InnoDB's internal memory allocator.

It worked for me.

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 fileSave 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)