SQL Joins problems
7 problems, easiest first.
- Customers Who Never Orderedjoins · null-handlingeasy
- Department Headcountjoins · aggregation · sortingeasy
- Campaign Click-to-Conversionjoins · subqueries · ctesmedium
- Loans by Missed Installmentsjoins · case-when · aggregationmedium
- Ticket First Response Timejoins · dates · null-handlingmedium
- Top Two Products per Categorytop-n-per-group · window-functions · joinsmedium
- Price Effective at Order Timesubqueries · dates · joinshard