Find names of the document without any images.
create table document_sections_images (section_id varchar, PRIMARY KEY (section_id)); create table documents (document_name varchar, PRIMARY KEY (document_name)); create table documents (document_name varchar, document_code varchar, PRIMARY KEY (document_name)); create table document_sections (document_code varchar, section_id varchar, PRIMARY KEY (document_code))
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