NEXT-ROWID attribute

Provides the ROWID of the data source row at which the next FILL operation should start. The AVM sets this attribute after each FILL operation in a series of FILL operations to retrieve data source rows in batches. You typically assign the value of this attribute to the RESTART-ROWID attribute before each FILL operation.

Data type: ROWID

Access: Readable/Writeable

Applies to: Data-source object handle

Syntax

NEXT-ROWID ( buffer-sequence-number|buffer-name )

buffer-sequence-number

An integer that represents the sequence number of a buffer in the list of buffers for the data-source object. Specify buffer-sequence-number to identify a buffer in the data-source object when the data-source object is defined against more than one database table buffer. The default is the first (or only) buffer in the data-source object.

Note: Sequence numbers for buffers in a data-source object start at one, where one represents the top level and subsequent numbers represent lower levels of join, if any.

buffer-name

A CHARACTER expression that evaluates to the name of a buffer in the list of buffers for the data-source object.

If an invalid buffer is specified, this attribute returns the Unknown value (?).

It is best to use the NEXT-ROWID attribute with a top-level ProDataSet temp-table, or a child temp-table that has only one parent record, because the AVM sets this attribute on the child temp-table for each parent record (as opposed to once per child temp-table).

Use this attribute when retrieving batches of data source rows containing stable data. Otherwise, it might be better to use a unique index to reopen the query associated with the data-source object to retrieve a specific batch of data source rows.

See also

BATCH-SIZE attribute, FILL( ) method, RESTART-ROWID attribute