V$RESERVED_WORDS displays a list of all SQL keywords. To determine whether a particular keyword is reserved in any way, check the RESERVED, RES_TYPE, RES_ATTR, and RES_SEMI columns.
| Column | Datatype | Description | 
|---|---|---|
| KEYWORD | VARCHAR2(30) | Name of the keyword | 
| LENGTH | NUMBER | Length of the keyword | 
| RESERVED | VARCHAR2(1) | Indicates whether the keyword cannot be used as an identifier ( Y) or whether the keyword is not reserved (N) | 
| RES_TYPE | VARCHAR2(1) | Indicates whether the keyword cannot be used as a type name ( Y) or whether the keyword is not reserved (N) | 
| RES_ATTR | VARCHAR2(1) | Indicates whether the keyword cannot be used as an attribute name ( Y) or whether the keyword is not reserved (N) | 
| RES_SEMI | VARCHAR2(1) | Indicates whether the keyword is not allowed as an identifier in certain situations, such as in DML ( Y) or whether the keyword is not reserved (N) | 
| DUPLICATE | VARCHAR2(1) | Indicates whether the keyword is a duplicate of another keyword ( Y) or whether the keyword is not a duplicate (N) |