Performance issue with Custom Report

Summary:

Dear All,

We are facing performance issue with one of the report. This report provides the information about the Project Budgets along with Expenditures details. Users are seeing error i.e. SQL Query time exceeds beyond 18000 seconds when they run the report for one year i.e. 2023. On analyzing the code, we found that the issue is occurring due to the huge amount of data in the temporary table i.e. flattened_tree, it has 4lakhs + of data and it will increase in near future. Could you please let me know is there any way to optimize the query/do we need to