How to Disable credit transaction log?

How can I disable transaction logs?

Previously I noticed if you have 30.000+ transaction logs in system then system becomes slow when it needs to calculate remaining balance for each user.

Early I solved this issue by adding a Cron job which deletes all transaction logs 1 time every day.

The problem now is that the system is processing more than 30.000 transactions under 24 hours, and systems becomes little slow towards the end of the day.

Is there any code I can add to function.php to avoid adding traction logs to mySQL?

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