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ur absolutely right that a simple FINAL clause won't work as expected with a materialized view like this, since the FINAL clause relies on the underlying table'
by deisteve 2y ago
ur absolutely right that a simple FINAL clause won't work as expected with a materialized view like this, since the FINAL clause relies on the underlying table's ordering to eliminate duplicates. With a materialized view, the ordering is based on the enabled, ts, and id columns, which might not be the same as the underlying table's ordering.
As for the other two deduplication methods, you're also correct that they might cause performance problems on large-ish tables. The DISTINCT ON method can be slow due to the need to sort the entire table, while the ROW_NUMBER() method can be resource-intensive due to the need to assign a unique row number to each row.
one possible solution to this problem is to use a combination of a materialized view and a secondary deduplication method. For example, you could create a materialized view that includes a ROW_NUMBER() or RANK() function to assign a unique identifier to each row, and then use a secondary query to eliminate duplicates based on this identifier.
you could consider using a different data modeling approach, such as using a separate table to store the deduplicated data, or using a data warehousing tool that supports more advanced deduplication techniques.
- Elucalidavah 2y ago> materialized view that includes a ROW_NUMBER() or RANK() function That won't work, as the materialized view's query is applied per inserted chunk, i.e. to each row separately in the most extreme cases.