Difference between length and vsize functions in oracle

length returns the length of the pased string , vsize function returns the number of bytes used to store tha data.

length returns the length of the string passed. If string is a number, it first converts the number into a string and then returns its length.As Oracle treats an empty string as null, the length of an empty string is also null.

if any non-english characters are there in a column, vsize function gives you howmany bytes used to store that value.

SQL> select length(sysdate) from dual;

LENGTH(SYSDATE)

---------------

              9

               

SQL> select vsize(sysdate) from dual;

VSIZE(SYSDATE)

--------------

             7

SQL> select sysdate from dual;

SYSDATE

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28-JAN-13