Question: a diagramming tool used to express the relationships between entities in a database is called a
[{'answer': 'entity -- relationship model'}, {'provenance': [{'wikipedia_id': '752991', 'title': 'Entity–relationship model', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 297, 'bleu_score': 0.818003038588317, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 93526847604920797}, 'section': 'Section::::Abstract.'}]}]