Hi Ajay,
AFAIK there is no single script available for migration from 6.5.0 to 7.23.0.
You will have to upgrade incrementally using available upgrade scripts. For any version, if there is a change in DB schema, then they have shared the upgrade script from its earlier version. So you will have to run them sequentially.
As per available scripts, there seems to be DB schema changes in versions 7.0, 7.7 & 7.11.
Regards,
Sudhish