SQL Loader is a bulk loader utility used for moving data from external files (.CSV, .txt, .dat, excel, .xml, etc.,)  into the Oracle database. SQL Loader supports various load formats, selective loading, and multi-table loads.

Look at the following example -

Have to be executed at the command prompt  -
            sqlldr username@server/password control=loader.ctl

Before executing this, you have to prepare a control file which is mentioned in the above command line (eg - loader.ctl)
This sample control file (loader.ctl) will load an external data file containing delimited data -
loader.ctl contents -
 
        load data
        infile 'c:\data\mydata.csv'
        into table emp
        fields terminated by "," optionally enclosed by "'"       
        (empno,
        empname,
        sal,
        deptno
        hiredate date "ddmonyyyy"
        )

This will automatically creates a log file and a bad file which will have the log details and rejected data respectively.

The above one is an example of simple SQL loader for delimited .csv file.

Hi,

To check which options are available in any release of SQL*Loader use this command:
sqlldr help=y

From the above post(Posted by: unknown)
He/She mentioned that   
Control file to load data:


Yes by typing this " sqlldr username@server/password control=loader.ctl" on the command prompt, log file file will get generated.
But to get bad file , you need to include
BADFILE 'c:\temp\filename.bad' in the control file.

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