Here's an example implementation in MSSQL - https://data.stackexchange.com/stackoverflow/query/edit/1873356 https://data.stackexchange.com/stackoverflow/query/e

Here's an example implementation in MSSQL - https://data.stackexchange.com/stackoverflow/query/edit/1873356 https://data.stackexchange.com/stackoverflow/query/edit/1873... No need to filter within the window function if you use subquery or CTE, which is supported everywhere.