Stop copying `Expr`s and LogicalPlans so much during Common Subexpression Elimination

[alamb]

Is your feature request related to a problem or challenge?

The common subexpression elimination pass copies many Exprs around. You can see this performance impact this has by looking at the screenshot from #9637 (comment)

While we will fix the copying plan problem in #9637 I think there is more work to be done in the common sub expression code itself, which copies a significant number of Exprs and Strings around

Describe the solution you'd like

Figure out how to avoid cloneing Exprs in the https://github.com/apache/arrow-datafusion/blob/main/datafusion/optimizer/src/common_subexpr_eliminate.rs

1. The Exprs themselves
2. Avoid creating Strings for Identifier

We should see a significant improvement in the sql_planner benchmarks:

cargo bench --bench sql_planner

Describe alternatives you've considered

No response

Additional context

I noticed this while reviewing #9871

[peter-toth]

I'm happy to take this issue, but I just noticed that there is a draft PR already: #10067. @alamb would you like to finish that PR?

[alamb]

I'm happy to take this issue, but I just noticed that there is a draft PR already: #10067. @alamb would you like to finish that PR?

I am on vacation this week (well, partial vacation as it is school break week) so I likely won't have time to work on #10067 until next week. If you have time to do so that would be great. Otherwise I will pick it up the following week

CSE is one of the passes that shows up in the planning benchmarks when I last profiled it, so I think this particular change will be very impactful to planning performance

[alamb]

(Thank you @peter-toth 🙏 -- it is much fun working with you)

[peter-toth]

Ok, got it. I'm happy to look into it, but not sure I can do it before Monday. Enjoy your partial vacation! 😄

[peter-toth]

I've started working on this, but it will surely take some time...