Ask DB details and query details before start working on it.
When did this query last took 2 hours?
What is the change in volume of data?
How many times this query runs each day?
Start and end time of this query execution for past 1 month.
Any DDL changes e.g. indexes, column etc
Could you provide the following data.
– Is there any difference in the amount of data, that below queries are pulling out ?
– How much more time the problematic SQLs are taking compared to previous days ?