Context: CREATE TABLE Documents (template_id VARCHAR); CREATE TABLE Templates (Template_Type_Code VARCHAR, template_id VARCHAR)
Question: What is the id and type code for the template used by the most documents?
Answer: SELECT T1.template_id, T2.Template_Type_Code FROM Documents AS T1 JOIN Templates AS T2 ON T1.template_id = T2.template_id GROUP BY T1.template_id ORDER BY COUNT(*) DESC LIMIT 1