The disk space used by a certain table??!!

Hi, there:

Oracle 8i for solaris 2.6
table 'tab': pctfree is 5, pctused is 75. database block size is 8k.

Analyae table 'tab':
analyze table tab estimate statistics sample 20 percent;

From the 'user_tables':
blocks: 1754
num_rows:62424
avg_row_len: 210

What does the 'blocks' mean in here?

From the 'dba_segments' get the corresponding info for this 'tab' table: bytes: 20971520
blocks: 2560

My questions:

1. what's the difference between the two 'blocks'?
2. what does the 'avg_row_len*num_rows' mean? Does it mean the real used disk space by the 'tab'?
3. If the 'bytes' in 'dba_segments' is the allocated disk space by table 'tab', why is it much more than 'avg_row_len'? since the pctfree is so small.

THanks a lot!!

Sent via Deja.com http://www.deja.com/
Before you buy. Received on Wed Jun 21 2000 - 00:00:00 CDT