The representation (mapping) in the Java programming language of an SQL ROWID value. An SQL ROWID is a built-in type, a value of which can be thought of as an address for its identified row in a database table. Whether that address is logical or, in any respects, physical is determined by its originating data source.
Methods in the interfaces ResultSet, CallableStatement,
and PreparedStatement, such as getRowId and setRowId
allow a programmer to access a SQL ROWID value. The RowId
interface provides a method
for representing the value of the ROWID as a byte array or as a
String.
The method getRowIdLifetime in the interface DatabaseMetaData,
can be used
to determine if a RowId object remains valid for the duration of the transaction in
which the RowId was created, the duration of the session in which
the RowId was created,
or, effectively, for as long as its identified row is not deleted. In addition
to specifying the duration of its valid lifetime outside its originating data
source, getRowIdLifetime specifies the duration of a ROWID
value's valid lifetime
within its originating data source. In this, it differs from a large object,
because there is no limit on the valid lifetime of a large object within its
originating data source.
All methods on the RowId interface must be fully implemented if the
JDBC driver supports the data type.
See Also
Public Method Summary
| abstract boolean | |
| abstract byte[] |
getBytes()
Returns an array of bytes representing the value of the SQL
ROWID
designated by this java.sql.RowId object. |
| abstract int |
hashCode()
Returns a hash code value of this
RowId object. |
| abstract String |
toString()
Returns a String representing the value of the SQL ROWID designated by this
java.sql.RowId object. |
Public Methods
public abstract boolean equals (Object obj)
Compares this RowId to the specified object. The result is
true if and only if the argument is not null and is a RowId
object that represents the same ROWID as this object.
It is important
to consider both the origin and the valid lifetime of a RowId
when comparing it to another RowId. If both are valid, and
both are from the same table on the same data source, then if they are equal
they identify
the same row; if one or more is no longer guaranteed to be valid, or if
they originate from different data sources, or different tables on the
same data source, they may be equal but still
not identify the same row.
Parameters
| obj | the Object to compare this RowId object
against. |
|---|
Returns
- true if the
RowIds are equal; false otherwise
public abstract byte[] getBytes ()
Returns an array of bytes representing the value of the SQL ROWID
designated by this java.sql.RowId object.
Returns
- an array of bytes, whose length is determined by the driver supplying the connection, representing the value of the ROWID designated by this java.sql.RowId object.
public abstract int hashCode ()
Returns a hash code value of this RowId object.
Returns
- a hash code for the
RowId
public abstract String toString ()
Returns a String representing the value of the SQL ROWID designated by this
java.sql.RowId object.
Like java.sql.Date.toString()
returns the contents of its DATE as the String "2004-03-17"
rather than as DATE literal in SQL (which would have been the String
DATE "2004-03-17"), toString()
returns the contents of its ROWID in a form specific to the driver supplying
the connection, and possibly not as a ROWID literal.
Returns
- a String whose format is determined by the driver supplying the
connection, representing the value of the
ROWIDdesignated by thisjava.sql.RowIdobject.