Server Utilities :: Skip Records On Condition SQL Loader

I tried to find about sql loader, tried googling and ended up with Orafaq .

1) Is there a way that you can skip few records in the control file.

Assume the control file is loading a file with three records.

CREATE TABLE emp_tab
(
Emp_id NUMBER(15,0),
Name CHAR(25),
Age NUMBER(15,0)
);

The text file is like this name.txt

1;sam;19;
2;jai;22;
;pam;33;

LOAD DATA
INFILE 'C:
ame.txt'
BADFILE 'C:
ame.bad'
DISCARDFILE 'C:
ame.dsc'
APPEND
INTO emp_tab
fields terminated by ";"
TRAILING NULLCOLS
( Emp_id ,
name,
age)

I want to skip the record 3 in the text file as it has no id, is there a way to do this.Can we skip a record based on a condition?

2) What needs to be included in the control file in order to get a return code?

3) Assume the return code = 0 for success and return code = 1 for failure, what will be the return code if 60 out 100 records are loaded and 40 are discarded and written to .bad file?

4) SQL loader does a auto commit, meaning the moment you run the control file, the records are inserted and commited, is there a way to avoid it ?