You can get the constraint names by querying the information_schema system views.
select CONSTRAINT_NAME from INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE WHERE TABLE_NAME = '<tablename>' AND COLUMN_NAME = 'IsClosed'
You can get the constraint names by querying the information_schema system views.
select CONSTRAINT_NAME from INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE WHERE TABLE_NAME = '<tablename>' AND COLUMN_NAME = 'IsClosed'