The code provided processes allCaserecords in a single transaction. Since it attempts to process over 10,000 records, it exceeds the Salesforce governor limit of 50,000 DML rows per transaction, causing the transaction to fail.
* Governor Limits on DML Rows (C):Salesforce enforces a governor limit of 50,000 rows for DML operations per transaction. In this case, if theSELECTquery retrieves over 50,000 records, theDatabase.
updatecall will hit this limit and throw aSystem.LimitException.
Reference:Apex Governor Limits
Why the Try-Catch Block Fails to Handle Limits (B & D):Governor limit exceptions (System.
LimitException) cannot be caught by try-catch blocks. Therefore, the exception cannot be handled, and the transaction will fail.