frafra

SELECT 'SELECT * FROM ' || src_table || ' JOIN ' || dst_table || ' ON (' ||
       string_agg(src_table || '.' || src_column || ' = ' || dst_table || '.' || dst_column, ' AND ') || ')'
  FROM (SELECT quote_ident(kcu.table_schema) || '.' || quote_ident(kcu.table_name) AS src_table,
               quote_ident(rcu.table_schema) || '.' || quote_ident(rcu.table_name) AS dst_table,
               quote_ident(kcu.column_name) AS src_column,
               quote_ident(rcu.column_name) AS dst_column
        FROM information_schema.referential_constraints rc
        LEFT JOIN information_schema.key_column_usage kcu
          USING (constraint_catalog, constraint_schema, constraint_name)
        LEFT JOIN information_schema.key_column_usage rcu -- referenced columns