oracle schema size

1SELECT sum(BYTES) / 1e6 AS SIZE_MB FROM DBA_SEGMENTS WHERE OWNER = 'schema_name';
2-- By type
3SELECT SEGMENT_TYPE, sum(BYTES) / 1e6 AS SIZE_MB FROM DBA_SEGMENTS
4    WHERE OWNER = 'schema_name' GROUP BY SEGMENT_TYPE;
5-- By schema
6SELECT OWNER, sum(BYTES) / 1e6 AS SIZE_MB FROM DBA_SEGMENTS GROUP BY OWNER
7    ORDER BY SIZE_MB DESC;