By default, a load done using SQL*Loader express mode assumes the following unless you specify otherwise:
If no data file is specified, then it looks for a file named table-name.dat in the current directory.
External tables is the load method. For some errors, SQL*Loader express mode automatically switches from the default external tables load method to direct path load. An example of when this might occur would be if a privilege violation caused the CREATE DIRECTORY SQL command to fail.
Fields are set up using the following:
names from table column names (the order of the fields matches the table column order)
types based on table column types
newline as the record delimiter
a comma as the field delimiter
no enclosure
left-right trimming
The DEGREE_OF_PARALLELISM parameter is set to AUTO.
Date and timestamp format use the NLS settings.
The NLS client character set is used.
New data is to be appended to the table if it already has data in it.
If a data file is not specified, then the data, log, and bad files take the following default names. (The %p is replaced with the process ID of the Oracle Database slave process.):
table-name.dat for the data file
table-name.log for the SQL*Loader log file
table-name_%p.log_xt for Oracle Database log files (for example, emp_17228.log_xt)
table-name_%p.bad for bad files
If one or more data files are specified (using the DATA parameter), then the log and bad files take the following default names. (The %p is replaced with the process ID of the server slave process.):
table-name.log for the SQL*Loader log file
table-name_%p.log_xt for the Oracle Database log files
first-data-file_%p.bad for the bad files
"DATA" parameter