Table schema:
CREATE TABLE document_sections_images (section_id VARCHAR); CREATE TABLE documents (document_name VARCHAR); CREATE TABLE documents (document_name VARCHAR, document_code VARCHAR); CREATE TABLE document_sections (document_code VARCHAR, section_id VARCHAR)

Question: Find names of the document without any images.
SQL: SELECT document_name FROM documents EXCEPT SELECT t1.document_name FROM documents AS t1 JOIN document_sections AS t2 ON t1.document_code = t2.document_code JOIN document_sections_images AS t3 ON t2.section_id = t3.section_id