CREATE TABLE ref_budget_codes (budget_type_code TEXT, budget_type_description TEXT)
CREATE TABLE ref_document_types (document_type_code TEXT, document_type_name TEXT, document_type_description TEXT)
CREATE TABLE documents (document_id DECIMAL, document_type_code TEXT, project_id DECIMAL, document_date TIME, document_name TEXT, document_description TEXT, other_details TEXT)
CREATE TABLE accounts (account_id DECIMAL, statement_id DECIMAL, account_details TEXT)
CREATE TABLE projects (project_id DECIMAL, project_details TEXT)
CREATE TABLE documents_with_expenses (document_id DECIMAL, budget_type_code TEXT, document_details TEXT)
CREATE TABLE statements (statement_id DECIMAL, statement_details TEXT)

Show budget type codes and the number of documents in each budget type.
SELECT budget_type_code, COUNT(*) FROM documents_with_expenses GROUP BY budget_type_code
SELECT "budget_type_code", COUNT(*) FROM "documents_with_expenses" GROUP BY "budget_type_code"