Copies a record wholesale from a source to
a target.
Syntax
RAW-TRANSFER
{ [ BUFFER ]buffer TO [ FIELD ]raw-field
|[ FIELD ]raw-field TO [ BUFFER ]buffer
|[ BUFFER ]buffer TO [ BUFFER ]buffer
}
[ NO-ERROR ]
|
- BUFFER
- Specifies a parameter is a buffer.
-
buffer
- A source or target database record.
Note: If the
source buffer contains only a partial field list, RAW-TRANSFER fails.
- FIELD
- Specifies a parameter is a raw-field.
-
raw-field
- A source or target data field of type RAW.
- NO-ERROR
- Suppresses ABL errors or error messages that would otherwise
occur and diverts them to the ERROR-STATUS system handle. If an error occurs, the action of the statement
is not done and execution continues with the next statement. If
the statement fails, any persistent side-effects of the statement
are backed out. If the statement includes an expression that contains
other executable elements, like methods, the work performed by these
elements may or may not be done, depending on the order the AVM
resolves the expression elements and the occurrence of the error.
To
check for errors after a statement that uses the NO-ERROR option:
- Check the ERROR-STATUS:ERROR attribute to see if the AVM raised
the ERROR condition.
- Check if the ERROR-STATUS:NUM-MESSAGES attribute is greater than
zero to see if the AVM generated error messages. ABL handle methods
used in a block without a CATCH end block treat errors as
warnings and do not raise ERROR, do not set the ERROR-STATUS:ERROR
attribute, but do add messages to the ERROR-STATUS system handle.
Therefore, this test is the better test for code using handle methods
without CATCH end blocks. ABL handle methods used in a block with a
CATCH end block raise ERROR and add messages to the error object
generated by the AVM. In this case, the AVM does not update the
ERROR-STATUS system handle.
- Use ERROR-STATUS:GET-MESSAGE( message-num )
to retrieve a particular message, where message-num is
1 for the first message.
If the statement does not include
the NO-ERROR option, you can use a CATCH end block to handle errors
raised by the statement.
Some other important usage notes
on the NO-ERROR option:
- NO-ERROR does not suppress errors
that raise the STOP or QUIT condition.
- A CATCH statement, which introduces a CATCH end block, is analogous
to a NO-ERROR option in that it also suppresses errors, but it does so
for an entire block of code. It is different in that the error messages
are contained in a class-based error object (generated by the AVM
or explicitly thrown), as opposed to the ERROR-STATUS system handle.
Also, if errors raised in the block are not handled by a compatible
CATCH block, ON ERROR phrase, or UNDO statement, then the error
is not suppressed, but handled with the default error processing
for that block type.
- When a statement contains the NO-ERROR option and resides in
a block with a CATCH end block, the NO-ERROR option takes precedence over
the CATCH block. That is, an error raised on the statement with
the NO-ERROR option will not be handled by a compatible CATCH end block.
The error is redirected to the ERROR-STATUS system handle as normal.
- If an error object is thrown to a statement that includes the NO-ERROR
option, then the information and messages in the error object will
be used to set the ERROR-STATUS system handle. This interoperability
feature is important for those integrating code that uses the traditional
NO-ERROR technique with the newer, structured error handling that
features error objects and CATCH end blocks.
Example
The
following ABL example performs a RAW-TRANSFER of a newly created
Customer record to the Record field of Replication-Log table:
TRIGGER PROCEDURE FOR REPLICATION-CREATE OF Customer.
CREATE Replication-Log.
ASSIGN
Replication-Log.Taskid = DBTASKID(LDBNAME(BUFFER Replication-Log))
Replication-Log.Table = 'Customer'
Replication-Log.Action = 'CREATE'.
RAW-TRANSFER Customer TO Replication-Log.Record.
|
For more information on database replication,
see OpenEdge Data Management: Database Administration.
Notes
- The
RAW-TRANSFER statement has several variations:
- The "buffer
to raw-field" variation copies the entire record from the buffer
to the raw field, prepending information on the source schema to
the raw field.
- The "raw-field to buffer" variation first checks that the source schema
information prepended to the raw field matches the schema of the
buffer. Then it creates a target record, if necessary. Finally it updates
each key field in the new record using values from the raw field,
which forces indexing to occur.
- The "buffer to buffer" variation is the same as the "raw-field
to buffer" variation, except that the source is a record in another buffer.
- The RAW-TRANSFER statement respects database triggers.
- You can marshal an OpenEdge database record so that it can
be sent across sockets by using the RAW-TRANSFER statement to put
the record into a RAW variable and then copying the RAW variable
to a MEMPTR that is being written to a socket. Use the PUT-BYTES
function to do this. You can unmarshal database records by using
the GET-BYTES function and then RAW-TRANSFER.
- At run time, the RAW-TRANSFER statement:
- Checks that
the signatures of the source data and the target data match.
- Compares source and target code page ids, and (if they are present
and different) translates the source's character data, writing any
warnings to the database log file and raising any error conditions.
- Creates the target record, if none exists, and runs all appropriate CREATE
and REPLICATE-CREATE triggers (unless the DISABLE TRIGGERS FOR LOAD
option is active for the target).
- Registers changes in key fields with the index manager by updating
each key field in the target when it differs from the source.
- Copies all data from the source record to the target record.
- Executes ASSIGN triggers for any modified fields (unless the DISABLE
TRIGGERS FOR LOAD option is active for the target).
- When using the RAW-TRANSFER statement to copy a record that contains
a BLOB or CLOB field, the AVM skips the BLOB or CLOB field and stores
the Unknown value (?) in the BLOB or CLOB field of the
target record.