I really appreciates your help.
I've figured out the problem, after many trials.
The problem lies with the mapping of Char on to String.

Environment
Oracle 8i (Oracle OCI8 Jdbc Driver)
Java 1.3
JDBC 1.1


Current scenario is:

1. I have a prepared Statement which takes one argument(String) in where clause

2. When i execute it i dont get any result set - no error nothing ! just an empty set


What i did (for test and trial):

1. I hard coded the values for place holders

2. prepared the statement

3. executed. it ran and returend ResultSet


Then...

1. I prepared the sql statement with a place holder of type String in where clause

2. Set the value of argument (to 4 char) using .setString and padded 16 spaces to it,

since database field is 20 char long.

3. executed the statement

4. It ran and returened ResultSet


Now, i hope you understand my problem.

I lookedup the java documentations and tutorails for mapping of datatypes. I found out that java
maps java.lang.String onto Char and Varchar2 automatically, therefore, one has not to convert from string to char[]. BUT this is not happening !

I am stuck here now... anyone can help me .