Trail Assembly

`System.QueryException`List has no rows for assignment to SObject

Apex September 9, 2026 6 min

`System.NullPointerException`Attempt to de-reference a null object

Apex September 9, 2026 7 min

`CANNOT_EXECUTE_FLOW_TRIGGER`a flow failed and took the save with it

Flow September 9, 2026 10 min

`CANNOT_INSERT_UPDATE_ACTIVATE_ENTITY`the wrapper that hides the real error

Apex September 9, 2026 8 min

`INSUFFICIENT_ACCESS_ON_CROSS_REFERENCE_ENTITY`the parent, not the record you saved

Apex September 9, 2026 8 min

`INVALID_CROSS_REFERENCE_KEY`the Id is valid but points at nothing usable

Apex September 9, 2026 7 min

`FIELD_CUSTOM_VALIDATION_EXCEPTION`finding which rule actually fired

Apex September 9, 2026 7 min

Synchronous vs asynchronous governor limits, side by side

Apex September 9, 2026 9 min

How to read LIMIT_USAGE_FOR_NS and prove whose code spent your limits

Apex September 9, 2026 9 min

Salesforce governor limits, organised by what actually trips them

Architecture September 9, 2026 11 min