SQL & PL/SQL

Hi,

I need to convert a string to date in oracle 11g.

The string's value is something like "2012/12/10 00:00:00"

Can you help me out with the below query


select segment1,segment2,segment3,segment4
from fnd_id_flex_structures fl,
per_analysis_criteria pac,
per_person_analyses ppa,
where trunc(sysdate) between pac.segment2 and pac.segment3
and fl.id_flex_num=ppa.id_flex_num
and pac.analysis_criteria_id=PPA.ANALYSIS_CRITERIA_ID
and id_flex_structure_code like 'XXXX_DETAILS';


Here I need to heck the segment values against the sysdate. the segment values are stored as varchar2.
How do I convert this to date and check it


thanks for your time