with data_21 as (select * from (select country_region, date as date_21, confirmed as confirmed_21, deaths as deaths_21,LAG(confirmed, 1) OVER (PARTITION BY country_region ORDER BY date ASC) AS prev_day_21,confirmed - LAG(confirmed, 1) OVER (PARTITION BY country_region ORDER BY date ASC) as…

Step 1: Turn on performance analyzer and select the analyze this visual option. After that, performance analyzer adds some lines: Click copy query and paste anywhere: And you see, there is the distinct value on it. Let's add something unique, like the orderID: These are auto-generated in…