Why these two methods using cursor to acquire table_name and then using this table_name to select its returned lines is always encoutered a weird error?

I've written two anonymous plsql blocks checking those tables (starting with "DBA_HIST_" in SYS schema of oracle database) returned line is 0, but it's always encountered an error.

Here's my PL/SQL code:

• *https://gist.github.com/guestart/1e0f49089530564a9f7c01b015416ad7*
  <https://gist.github.com/guestart/1e0f49089530564a9f7c01b015416ad7>
  
• *https://gist.github.com/guestart/0ca72e5344aa3ecaf26b905337e1dcd8*
  <https://gist.github.com/guestart/0ca72e5344aa3ecaf26b905337e1dcd8>
  

Could you help me troubleshooting it? Thanks beforehand 🙏.

Best Regards
Quanwen Zhao

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