The VSIZE function

 

To determine the exact number of bytes occupied of a table. The function 'VSIZE' reports the exact number of bytes allocated by Oracle for data.

For example, to determine the size of a table called 'fuzzy_pink_slippers' with columns 'col_a', 'col_b', ...'col_n', execute the following SQL statement to find the exact size of the table:

SELECT SUM (VSIZE (col_a)) + SUM (VSIZE (col_b)) + ... +
SUM (VSIZE (col_n))
FROM fuzzy_pink_slippers;