select a.grp,a.file_name,a.tablespace_name,a.bytes/1024/1024/1024 as size_GB, sum(bytes/1024/1024/1024) over (partition by tablespace_name) as TBL_FULL_SIZE from dba_data_files 
match_recognize (
order by file_id
measures
match_number() as grp,
count(file_id) as num_of_files,
file_name as fname,
tablespace_name as tbl
all rows per match
pattern ( strt limit_size* )
define
limit_size as
sum(bytes)/1024/1024/1024 < 300
) a
order by grp;