Explanation:
Box 1: No
Short term retention is set to 21 days.
Note: Short term retention policy is used to address point-in-time restores whereas a long-term retention policy is used to address restores from long-term or older backups for various audit and compliance purposes. We can also save these backup files as part of a short-term retention policy for up to 7-35 days.
Box 2: Yes
Weekly retention is set to P52W, which stands for a periodic frequency of 52 weeks (364 days).
Note: -WeeklyRetention
The Weekly Retention. If just a number is passed instead of an ISO 8601 string, days will be assumed as the units. There is a minimum of 7 days and a maximum of 10 years.
Box 3: No
Yearly retention is set to PSY.
Note: -YearlyRetention
The Yearly Retention. If just a number is passed instead of an ISO 8601 string, days will be assumed as the units. There is a minimum of 7 days and a maximum of 10 years.
Reference:
https://strata.opengamma.io/apidocs/com/opengamma/strata/basics/schedule/Frequency.html
https://docs.microsoft.com/en-us/powershell/module/az.sql/set-azsqldatabasebackupshorttermretentionpolicy?view=azps-7.2.0
https://docs.microsoft.com/en-us/powershell/module/az.sql/set-azsqldatabasebackuplongtermretentionpolicy?view=azps-7.2.0