SELECT segment_name AS "TABLE_NAME", SUM (BYTES) AS "[Bytes]", SUM (BYTES) / 1024 AS "[Kb]", SUM (BYTES) / (1024*1024) AS "[Mb]", SUM (BYTES) / (1024*1024*1024) AS "[Gb]" FROM dba_segments WHERE segment_name = 'NOMBRE_TABLA' and segment_type = 'TABLE' GROUP BY segment_name;
En dónde en segment_name se especifica el nombre de la tabla que se desea consultar.