CREATE TABLE Ref_Budget_Codes (Budget_Type_code VARCHAR, budget_type_Description VARCHAR)
CREATE TABLE Documents_with_expenses (document_id VARCHAR, Budget_Type_code VARCHAR)

Show ids for all documents with budget types described as 'Government'.
SELECT T1.document_id FROM Documents_with_expenses AS T1 JOIN Ref_Budget_Codes AS T2 ON T1.Budget_Type_code = T2.Budget_Type_code WHERE T2.budget_type_Description = "Government"
SELECT "T1"."document_id" FROM "Documents_with_expenses" AS "T1" JOIN "Ref_Budget_Codes" AS "T2" ON "Government" = "T2"."budget_type_Description" AND "T1"."Budget_Type_code" = "T2"."Budget_Type_code"