How can calculate a table actual size ?

[danny yang]

Hi all,
I want to find the way to fix out this problem as title .
if you have got the good idea and solution please kindly
help me .
thanx

[drishti]

get the values of num_rows and avg_row_size from dba_tables,after computing statistics of the table,
size=num_rows*avg_row_size+some space for headers

[danny yang]

Hi drishti,
Thanks a lot .

[Slaine]

May I just add if you have computed statistics on the table and your optimiser mode is rule your performance could be completey foobar'd

If the Optimiser mode is rule then ANALYZE TABLE TABLE_NAME DELETE STATISTICS

If the optimiser mode is choose you may need to analyze some or all of the other tables
I hope this helps
Allan

[gtm]

After Analyzing the table, calulate the no of blocks and multiply by block size.

SELECT COUNT(DISTINCT(SUBSTR(ROWID,1,8)||SUBSTR(ROWID,15,4))) BLKS FROM TABLE_NAME ;

size = BLKS * BLOCK_SIZE

[gtm]

Another Method

After Analyzing the table, calulate the no of blocks and multiply by block size.

SELECT COUNT(DISTINCT(SUBSTR(ROWID,1,8)||SUBSTR(ROWID,15,4))) BLKS FROM TABLE_NAME ;

size = BLKS * BLOCK_SIZE

[danny yang]

Hi gtm,
Thanx a lot .