tricky sql report...

All, Im doing an inventory report to provide monthly summaries of space being used by databases in the envioriments. I have a reporting table with the following columns

MONTH, SCHEMA , SPACE_USED, SPACE_FREE This table will be populated by a sql script ran against a hard coded list of databases 1x per month

the rub is Id like the report to look like this

        DB1, DB2, DB3, COMBINED
JAN 22 ,10,20, 52
FEB 1, 2, 3, 6
MAR 1, 1, 1, 3 The sql to populate the reporting table

create table DB_SPACE

	(MONTH date,
	SCHEMA varchar(10),
	USED_MB varchar(16),
	FREE_SPACE_MB varchar(16))

insert into DB_SPACE

SELECT 	sysdate MONTH,
        SYS_CONTEXT('USERENV', 'CURRENT_SCHEMA', 8) SCHEMA,
	((df.bytes / 1024 / 1024) - NVL (SUM (dfs.bytes) / 1024 / 1024,0)) USED_MB,
	NVL (SUM (dfs.bytes) / 1024 / 1024, 0) FREE_SPACE_MB
  	FROM v$datafile df, dba_free_space dfs
  	WHERE df.file# = dfs.file_id(+)
	GROUP BY dfs.file_id, df.NAME, df.file#, df.bytes;

I know this can be done but havent had success goggling for this sort of query

Thanks!
bob

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