Date problem in oracle 11g

Question

iam New to oracle 11g but familiar with SQL 2005
i have a table Patient which has a column Date_Of_Birth has datatype Date
and iam writing a query in which if Date_Of_Birth column has a value
*01/01/1900* then i should be replaced by *' ' or balnk*
otherwise show date value for that i have made use of
case
query
select case(Date_Of_Birth)-------------this is my column
when '01/01/1900'
then ''
ELSE TO_CHAR( Patient.Date_Of_Birth, 'DD/MM/YYYY')
END Date_Of_Birth
from Patient -------------my table
but error is comming
Error starting at line 1 in command:
select case(Date_Of_Birth)
when '01/01/1900'
then ''
ELSE TO_CHAR( Patient.Date_Of_Birth, 'DD/MM/YYYY')
END Date_Of_Birth
from Patient
Error at Command Line:2 Column:5
Error report:
SQL Error: ORA-00932: inconsistent datatypes: expected DATE got CHAR
00932. 00000 - "inconsistent datatypes: expected %s got %s"
*Cause:   
*Action:
Edited by: user13066438 on Jan 24, 2011 9:38 PM

Answer 1

Hi there
you have date data type in Date_Of_Birth you have to use to_date function
try this
select case((Date_Of_Birth)when to_date('01/01/1900', 'DD/MM/YYYY')
then ''
ELSE TO_CHAR(Patient.Date_Of_Birth, 'DD/MM/YYYY')
END Date_Of_Birth
from table_name;regards
Hitesh