Overlap Boundaries

Columns (other than Overlap) in the embedded database tables occupy contiguous lengths of bytes. Overlap columns can overlap these columns starting and ending at any byte position.

Use this dialog to define the byte position boundaries for an overlap column.

Note: Overlap columns were designed to allow developers to create multi-segment (multi-column) relationships before full support for multi-segment relationships was added to DataFlex (introduced in revision 11.0). Overlap columns are now considered a legacy technique and supported only as such. Developers are encouraged to use proper multi-segment relationships instead of overlap columns when creating new relationships and to convert existing overlap columns to proper multi-segment relationships whenever possible. Read more about Overlap columns here.

Data Entry

Start Offset

Start offset is the byte-offset marking the first byte of the overlap column. This is counted from the beginning position of the table's first column.

End Offset

End offset is the byte-offset marking the last byte of the overlap column. This is counted from the beginning position of the table's first column. You may not specify an end offset that is less than the start offset.

Start Column

You can calculate the start offset by selecting a column in the Start Column combo. When you select a start column, its start offset is placed into the Start Offset for the overlap.

End Column

You can calculate the end offset by selecting a column in the End Column combo. When you select an end column, its end offset is placed into the End Offset for the overlap.

Actions

• Ok
• Cancel
• Help

See Also

• Defining Columns
• Table Editor