Migration From Activity To Camunda

Hello Team , We are in migration process from Activity 5.22 to Camunda 7.5+.
Our current Activity DB is on the Oracle server. When we have run the script from this source https://github.com/camunda-consulting/code/blob/master/snippets/activiti-migration/scripts/postgres-1-upgrade.sql

we have get bunch of errors due incompatibility of the sqls in that script:
example :
ALTER TABLE ACT_RU_JOBDEF
ADD JOB_PRIORITY_ bigint
Error report - ORA-00902: invalid datatype 00902. 00000 - “invalid datatype”

So my guess those the scripts are for fully workable and need to be adjusted to the specific Database?
Have some one gone through DB migration (especially in Oracle) and could share tips / info Thanks in Advance

Can you confirm that you’re actually running the correct script? the name of the scrip you posted is intended for a postgres database, the oracle one is here:
code/oracle-1-upgrade.sql at master · camunda-consulting/code · GitHub