Default: The default is that there is no enclosure character.
ENCLOSED_BY parameter specifies a field enclosure character.
Syntax and Description
The enclosure character must be a single character. It can be in hexadecimal notation.
The same character must be used to signify both the beginning and the ending of the enclosure.
In the following example, the field data is enclosed by the '/' character (forward slash).
> sqlldr hr TABLE=employees ENCLOSED_BY='/'