Joining query

Question

hi everyone,
my issue for today is "can we join two queries "
select name from v$database;
select bytes/1024/1024/1024,count(segment_name) from dba_segments where segment_name = 'tablename';
could you guys please help me out with this one as well
i actually want my output to be something like below
Name bytes count(segments_name)
db 1800 27
Regards
shareef

Answer 1

First of all:
select bytes/1024/1024/1024,count(segment_name) from dba_segments where segment_name = 'tablename';is wrong. Count implies aggregation, su you need to sum bytes to get total size. Anyway:
select  name,
        sum(bytes)/1024/1024/1024 total_bytes_mb,
        count(segment_name) count
  from  v$database,
        dba_segments
  where segment_name = 'tablename'
  group by name
/For example:
select  name,
        sum(bytes)/1024/1024/1024 total_bytes_mb,
        count(segment_name) count
  from  v$database,
        dba_segments
  where segment_name = 'EMP'
  group by name
NAME      TOTAL_BYTES_MB      COUNT
SOL10         .000183105          3
SQL> SY.