PERF: avoid SQL MetaData reflection in init #45260
- [x] closes #45260


Hello @fangchenli! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:



There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2022-01-15 20:36:30 UTC > Thanks for the quick fix, looks good!
> 
> One comment: we also have a `tables` property on the `SQLDatabase`. It doesn't seem to be used internally in the `SQLDatabase` class itself, but to keep that property useful, we might need to reflect `meta` at that moment to actually get a list of tables? (no idea actually, just guessing)

Thanks for the comment. I'll take a look at the `tables` property later. thanks @fangchenli very nice ! @meeseeksdev backport 1.4.x Something went wrong ... Please have a look at my logs.