You may load any number of a table's columns. Columns defined in the database, but not specified in the control file, are assigned null values.
A column specification is the name of the column, followed by a specification for the value to be put in that column. The list of columns is enclosed by parentheses and separated with commas as follows:
(columnspec,columnspec, ...)
Each column name (unless it is marked FILLER) must correspond to a column of the table named in the INTO TABLE clause. A column name must be enclosed in quotation marks if it is a SQL or SQL*Loader reserved word, contains special characters, or is case sensitive.
If the value is to be generated by SQL*Loader, then the specification includes the RECNUM, SEQUENCE, or CONSTANT parameter. See "Using SQL*Loader to Generate Data for Input".
If the column's value is read from the data file, then the data field that contains the column's value is specified. In this case, the column specification includes a column name that identifies a column in the database table, and a field specification that describes a field in a data record. The field specification includes position, data type, null restrictions, and defaults.
It is not necessary to specify all attributes when loading column objects. Any missing attributes will be set to NULL.