When executing a multi-row INSERT using array notation, i.e.:
If there is an error in this statement for example a PRIMARY KEY error, then there is no way of knowing which element in the array caused the error. This really limits the usefulness of array INSERTs which is an issue as this is a really good way to increase INSERT performance.
The suggestion is to add the ability to find the index of the value with an issue by adding a new function to the API. This also need to be made available through Stored Procedures so maybe it should be complemented with a SQL-function. In addition, one such function will also be necessary, for the same reason, for prepared statements.