Offset Pagination - Trigger COUNT(*) OVER And Return List<dto>
Description: Typically, in offset pagination, there is one query needed for fetching the data and one for counting the total number of records. But, we can fetch this information in a single database rountrip via a SELECT COUNT subquery nested in the main SELECT. Even better, for databases vendors that support Window Functions there is a solution relying on COUNT(*) OVER() as in this application that uses this window function in a native query against MySQL 8. So, prefer this one instead of SELECT COUNT subquery.
Key points:
- create a DTO projection that contains getters for the columns that should be fetched and an extra-column for mapping the return of the
COUNT(*) OVER()window function - write a native query relying on this window function
Example:
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