RAW-TRANSFER statement

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.

See also 

DISABLE TRIGGERS statement, LDBNAME function, RAW-TRANSFER( ) method, RECORD-LENGTH function