Use a subquery instead of a join for the assignment user filter #6582
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In general a subquery is better for filtering, in this case because: - It allows us to compose a query better, we don't have to worry about missing/duplicating a join - It can be faster for non-correlated subqueries (ie queries that produce the same values for all rows). This should be the case here. - They don't introduce duplicate rows, we can remove the distinct here.
acelaya
approved these changes
Aug 21, 2024
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For:
In general a subquery is better for filtering, in this case because:
It allows us to compose a query better, we don't have to worry about missing/duplicating a join
It can be faster for non-correlated subqueries (ie queries that produce the same values for all rows). This should be the case here.
They don't introduce duplicate rows, we can remove the distinct here.
No behaviour changes, to sanity check:
Launch the dashboard and list assignments in the dropdown and for one particular course.
Use the student drop down to filter assignments.