Just wondering in what order does the Portal display the records?
All records > Sort > Filter
Looking ways to optomise the portal.
If you have sorting setup, all records are loaded to sort.
If you have filtering setup, all records are loaded so they can be filtered.
Both of those actions are performance hits that will deter from performance. If you don't need to sort or filter, don't. If you need to sort, do so in the relationship settings as it's slightly faster than portal sort settings. If you need to filter, make sure all fields referenced in the filter are indexed for performance.
Unfiltered, unsorted portals will display the related records in the order the related records were created, oldest first, newest last. I'd add to Mike's comment that all RELATED records are loaded if you're sorting or filtering. I second his comments on performance, as well. Use relationships wisely to filter what you need at the relationship level as much as possible.
“All related” is a key detail here. Sometimes, a Cartesian join works fine during testing when there are relatively few records and then bogs down when far more real records are present. The fix can sometimes be to come up with a relationship that matches to fewer records that are then sorted/filtered.
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