SQL*Loader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that puts little limitation on the format of the data in the datafile.
SQL Loader loads data
from multiple datafiles during the same load session.
into multiple tables during the same load session.
Data File
SQL*Loader reads data from one or more files specified in the control file. From SQL*Loader's perspective, the data in the datafile is organized as records.
It may be in the form of (.csv, .dat, .txt)
Data File is in the form of Delimiter Separator or Fixed Position File.
Control File
Control file used for loading the data.
Provide the interface between data file and table
The control file tells SQL*Loader where to find the data, how to parse and interpret the data, and where to insert the data.
Extension of Control file is .ctl
Log File
Provide the information about the process of loading from data file to database.
Extension of log file is .txt.
Bad File
BAD specifies the name of the bad file created by SQL*Loader to store records that cause errors during insert or that are improperly formatted.
A bad file is not automatically created if there are no rejected records.
extension of .bad
Discard File
Business Logic “When condition of WHERE CLAUSE is not true”.
extension of .dsc