canModifyAllInstances property Null safety
Confirms that a query has no predicate before executing it.
This is a safety measure for update and delete queries to prevent accidentally updating or deleting every row. This flag defaults to false, meaning that if this query is either an update or a delete, but contains no predicate, it will fail. If a query is meant to update or delete every row on a table, you may set this to true to allow this query to proceed.